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.github/workflows/build.yaml+3−3 Changelog.md+159 LICENSE+1−1 README.md+4 cabal.project−5 cabal.project.haskell-nix−6 default.nix+5−5 docs/concepts/dbtype.rst+18−17 docs/concepts/expr.rst+2−2 docs/concepts/insert.rst+181 docs/concepts/queries.rst+9−9 docs/cookbook.rst+10−8 docs/index.rst+2−1 docs/tutorial.rst+64−47 nix/sources.json+9−9 nix/sources.nix+66−20 rel8.cabal+70−30 shell.nix+1−1 src/Rel8.hs+371−41 src/Rel8/Aggregate.hs+45−124 src/Rel8/Aggregate/Legacy.hs−92 src/Rel8/Column.hs+31 src/Rel8/Column/ADT.hs+23 src/Rel8/Column/Either.hs+26 src/Rel8/Column/Lift.hs+23 src/Rel8/Column/List.hs+25 src/Rel8/Column/Maybe.hs+26 src/Rel8/Column/NonEmpty.hs+27 src/Rel8/Column/Null.hs+26 src/Rel8/Column/These.hs+29 src/Rel8/Expr.hs+40−43 src/Rel8/Expr.hs-boot+6−8 src/Rel8/Expr/Aggregate.hs+53−115 src/Rel8/Expr/Array.hs+6−6 src/Rel8/Expr/Default.hs+35 src/Rel8/Expr/Eq.hs+1−1 src/Rel8/Expr/Function.hs+1−1 src/Rel8/Expr/Null.hs+3−3 src/Rel8/Expr/Num.hs+43−10 src/Rel8/Expr/Opaleye.hs+19−5 src/Rel8/Expr/Ord.hs+10−11 src/Rel8/Expr/Sequence.hs+22 src/Rel8/Expr/Text.hs+24−4 src/Rel8/Expr/Time.hs+2−2 src/Rel8/Expr/Window.hs+121 src/Rel8/FCF.hs+9−1 src/Rel8/Generic/Construction.hs+352 src/Rel8/Generic/Construction/ADT.hs+478 src/Rel8/Generic/Construction/Record.hs+168 src/Rel8/Generic/Map.hs+49 src/Rel8/Generic/Record.hs+31−28 src/Rel8/Generic/Rel8able.hs+281 src/Rel8/Generic/Table.hs+72−96 src/Rel8/Generic/Table/ADT.hs+221 src/Rel8/Generic/Table/Record.hs+181 src/Rel8/Kind/Algebra.hs+38 src/Rel8/Kind/Context.hs+56 src/Rel8/Kind/Labels.hs−61 src/Rel8/Kind/Necessity.hs−38 src/Rel8/Order.hs+2−9 src/Rel8/Query.hs+181−7 src/Rel8/Query.hs-boot+3−1 src/Rel8/Query/Aggregate.hs+22−2 src/Rel8/Query/Distinct.hs+4−9 src/Rel8/Query/Each.hs+3−3 src/Rel8/Query/Either.hs+27−17 src/Rel8/Query/Evaluate.hs+49 src/Rel8/Query/Exists.hs+15−17 src/Rel8/Query/Indexed.hs+21 src/Rel8/Query/List.hs+93−14 src/Rel8/Query/Maybe.hs+26−45 src/Rel8/Query/Null.hs+15 src/Rel8/Query/Opaleye.hs+41−5 src/Rel8/Query/Rebind.hs+27 src/Rel8/Query/SQL.hs+6−59 src/Rel8/Query/Set.hs+6−6 src/Rel8/Query/These.hs+52−45 src/Rel8/Query/Window.hs+26 src/Rel8/Schema/Column.hs−29 src/Rel8/Schema/Context.hs−28 src/Rel8/Schema/Context/Label.hs−60 src/Rel8/Schema/Context/Nullify.hs+105−160 src/Rel8/Schema/Field.hs+23−694 src/Rel8/Schema/Generic.hs−150 src/Rel8/Schema/HKD.hs−303 src/Rel8/Schema/HTable.hs+55−23 src/Rel8/Schema/HTable/Either.hs+2−4 src/Rel8/Schema/HTable/Identity.hs+16−17 src/Rel8/Schema/HTable/Label.hs+37−50 src/Rel8/Schema/HTable/MapTable.hs+22−12 src/Rel8/Schema/HTable/Maybe.hs+2−4 src/Rel8/Schema/HTable/Nullify.hs+52−37 src/Rel8/Schema/HTable/These.hs+2−4 src/Rel8/Schema/HTable/Type.hs−61 src/Rel8/Schema/HTable/Vectorize.hs+39−47 src/Rel8/Schema/Insert.hs−161 src/Rel8/Schema/Kind.hs+8−17 src/Rel8/Schema/Name.hs+36−51 src/Rel8/Schema/Result.hs+41−3 src/Rel8/Schema/Spec.hs+17−45 src/Rel8/Schema/Spec/ConstrainDBType.hs−64 src/Rel8/Schema/Spec/ConstrainType.hs−31 src/Rel8/Schema/Structure.hs−17 src/Rel8/Schema/Table.hs+20 src/Rel8/Statement/Delete.hs+35−48 src/Rel8/Statement/Insert.hs+60−60 src/Rel8/Statement/OnConflict.hs+106 src/Rel8/Statement/Returning.hs+114−10 src/Rel8/Statement/SQL.hs+29 src/Rel8/Statement/Select.hs+120−35 src/Rel8/Statement/Set.hs+33 src/Rel8/Statement/Update.hs+38−60 src/Rel8/Statement/Using.hs+36 src/Rel8/Statement/View.hs+43−28 src/Rel8/Statement/Where.hs+31 src/Rel8/Table.hs+95−206 src/Rel8/Table/ADT.hs+173 src/Rel8/Table/Aggregate.hs+37−36 src/Rel8/Table/Bool.hs+12−6 src/Rel8/Table/Cols.hs+50 src/Rel8/Table/Either.hs+154−126 src/Rel8/Table/Eq.hs+12−39 src/Rel8/Table/HKD.hs+228 src/Rel8/Table/Insert.hs−51 src/Rel8/Table/List.hs+83−35 src/Rel8/Table/Maybe.hs+124−119 src/Rel8/Table/Name.hs+37−26 src/Rel8/Table/NonEmpty.hs+84−33 src/Rel8/Table/Null.hs+147 src/Rel8/Table/Nullify.hs+211 src/Rel8/Table/Opaleye.hs+84−75 src/Rel8/Table/Ord.hs+17−47 src/Rel8/Table/Order.hs+13−16 src/Rel8/Table/Projection.hs+73 src/Rel8/Table/Recontextualize.hs−90 src/Rel8/Table/Rel8able.hs+92 src/Rel8/Table/Serialize.hs+19−241 src/Rel8/Table/Tag.hs−97 src/Rel8/Table/These.hs+212−141 src/Rel8/Table/Transpose.hs+46 src/Rel8/Table/Undefined.hs+5−5 src/Rel8/Table/Window.hs+43 src/Rel8/Tabulate.hs+530−228 src/Rel8/Type.hs+9−8 src/Rel8/Type/Array.hs+46−26 src/Rel8/Type/Array1D.hs−139 src/Rel8/Type/Composite.hs+90−39 src/Rel8/Type/Enum.hs+86−33 src/Rel8/Type/JSONBEncoded.hs+4 src/Rel8/Type/JSONEncoded.hs+4 src/Rel8/Type/Monoid.hs+2−2 src/Rel8/Type/Num.hs+11−2 src/Rel8/Type/Ord.hs−2 src/Rel8/Type/ReadShow.hs+3 src/Rel8/Type/Semigroup.hs+4−2 src/Rel8/Type/Tag.hs+14−1 src/Rel8/Window.hs+97 tests/Main.hs+323−159 src/Rel8/Schema/Generic/Test.hs → tests/Rel8/Generic/Rel8able/Test.hs+87−14
.github/workflows/build.yaml+3−3
@@ -9,14 +9,14 @@ jobs:
99 persist-credentials: false
1010 submodules: true
1111
12− - uses: cachix/install-nix-action@v12
12+ - uses: cachix/install-nix-action@v14.1
1313 with:
1414 nix_path: nixpkgs=channel:nixos-unstable
1515 extra_nix_config: |
1616 trusted-public-keys = cache.nixos.org-1:6NCHdD59X431o0gWypbMrAURkbJ16ZPMQFGspcDShjY= hydra.iohk.io:f/Ea+s+dFdN+3Y/G+FDgSq+a5NEWhJGzdjvKNGv0/EQ=
17− substituters = https://cache.nixos.org/ https://hydra.iohk.io
17+ substituters = https://cache.nixos.org/ https://cache.iog.io
1818
19− - uses: cachix/cachix-action@v8
19+ - uses: cachix/cachix-action@v10
2020 with:
2121 name: rel8
2222 authToken: '${{ secrets.CACHIX_AUTH_TOKEN }}'
Changelog.mdnew file+159
@@ -0,0 +1,159 @@
1+# 1.4.0.0 (2002-08-17)
2+
3+## Breaking changes
4+
5+* The behavior of `greatest`/`least` has been corrected, and was previously flipped. ([#183](https://github.com/circuithub/rel8/pull/183))
6+
7+## New features
8+
9+* `NullTable`/`HNull` have been added. This is an alternative to `MaybeTable` that doesn't use a tag columns. It's less flexible (no `Functor` or `Applicative` instance) and is meaningless when used with a table that has no non-nullable columns (so nesting `NullTable` is redundant). But in situations where the underlying `Table` does have non-nullable columns, it can losslessly converted to and from `MaybeTable`. It is useful for embedding into a base table when you don't want to store the extra tag column in your schema. ([#173](https://github.com/circuithub/rel8/pull/173))
10+* Add `fromMaybeTable`. ([#179](https://github.com/circuithub/rel8/pull/179))
11+* Add `alignMaybeTable`. ([#196](https://github.com/circuithub/rel8/pull/196))
12+
13+## Improvements
14+
15+* Optimize implementation of `AltTable` for `Tabulation` ([#178](https://github.com/circuithub/rel8/pull/178))
16+
17+## Other
18+
19+* Documentation improvements for `HADT`. ([#177](https://github.com/circuithub/rel8/pull/177))
20+* Document example usage of `groupBy`. ([#184](https://github.com/circuithub/rel8/pull/184))
21+* Build with and require Opaleye >= 0.9.3.3. ([#190](https://github.com/circuithub/rel8/pull/190))
22+* Build with `hasql` 1.6. ([#195](https://github.com/circuithub/rel8/pull/195))
23+
24+# 1.3.1.0 (2022-01-20)
25+
26+## Other
27+
28+* Rel8 now requires Opaleye >= 0.9.1. ([#165](https://github.com/circuithub/rel8/pull/165))
29+
30+# 1.3.0.0 (2022-01-31)
31+
32+## Breaking changes
33+
34+* `div` and `mod` have been changed to match Haskell semantics. If you need the PostgreSQL `div()` and `mod()` functions, use `quot` and `rem`. While this is not an API change, we feel this is a breaking change in semantics and have bumped the major version number. ([#155](https://github.com/circuithub/rel8/pull/155))
35+
36+## New features
37+
38+* `divMod` and `quotRem` functions have been added, matching Haskell's `Prelude` functions. ([#155](https://github.com/circuithub/rel8/pull/155))
39+* `avg` and `mode` aggregation functions to find the mean value of an expression, or the most common row in a query, respectively. ([#152](https://github.com/circuithub/rel8/pull/152))
40+* The full `EqTable` and `OrdTable` classes have been exported, allowing for instances to be manually created. ([#157](https://github.com/circuithub/rel8/pull/157))
41+* Added `like` and `ilike` (for the `LIKE` and `ILIKE` operators). ([#146](https://github.com/circuithub/rel8/pull/146))
42+
43+## Other
44+
45+* Rel8 now requires Opaleye 0.9. ([#158](https://github.com/circuithub/rel8/pull/158))
46+* Rel8's test suite supports Hedgehog 1.1. ([#160](https://github.com/circuithub/rel8/pull/160))
47+* The documentation for binary operations has been corrected. ([#162](https://github.com/circuithub/rel8/pull/162))
48+
49+# 1.2.2.0 (2021-11-21)
50+
51+## Other
52+
53+* Support GHC 9.2 ([#145](https://github.com/circuithub/rel8/pull/145))
54+* Correct the documentation for `except` ([#147](https://github.com/circuithub/rel8/pull/147))
55+* Support `hasql` 1.5 ([#149](https://github.com/circuithub/rel8/pull/149))
56+
57+# 1.2.1.0 (2021-11-21)
58+
59+## New features
60+
61+* `castTable` has been added, which casts all columns selected from in `Query` according to the types of columns. This can occasionally be useful when using `many`/`some` on older PostgreSQL versions. ([#137](https://github.com/circuithub/rel8/pull/137))
62+
63+* Added `<:`, `<=:`, `>:`, `>=:`, `greatest` and `least`, which sort all columns in a table lexicographically. These operators are like the `<.` operators which operate on `Expr`s, but the `<:` operate on entire tables. ([#139](https://github.com/circuithub/rel8/pull/139))
64+
65+## Other
66+
67+* Support opaleye-0.8 ([#142](https://github.com/circuithub/rel8/pull/142))
68+
69+# 1.2.0.0 (2021-10-22)
70+
71+## New features
72+
73+* New `$*` and `$+` operators for projecting out of `ListTable` and `NonEmptyTable` respectively (analogous to the existing `$?` for `MaybeTable`). ([#125](https://github.com/circuithub/rel8/pull/125))
74+
75+## Bug fixes
76+
77+* Fix `UPSERT` support (and add tests), which was broken due to a typo inside Rel8 that made it impossible to construct `Projection`s which are needed by `UPSERT`. ([#134](https://github.com/circuithub/rel8/pull/134))
78+
79+* Remove `DBMin` and `DBMax` instances for `Bool`, which are invalid as far as Postgres is concerned. `and` and `or` can be used to achieve the same thing. ([#126](https://github.com/circuithub/rel8/pull/126))
80+
81+* Fix `aggregateMaybeTable`, `aggregateEitherTable` and `aggregateTheseTable`, which generated invalid SQL previously. ([#127](https://github.com/circuithub/rel8/pull/127))
82+
83+## Breaking changes
84+
85+* `rebind` now takes an additional argument for the "name" of the binding. ([#128](https://github.com/circuithub/rel8/pull/128))
86+
87+# 1.1.0.0 (2021-07-16)
88+
89+## New features
90+
91+* You can derive `Rel8able` for "vanilla" higher-kinded data types - data types that don't use the `Column` type family. For example, the following is now possible:
92+
93+ ```haskell
94+ data MyTable f = MyTable
95+ { myTableX :: f Int32
96+ , myTableY :: f Text
97+ } deriving (Generic, Rel8able)
98+ ```
99+
100+* The `Projectable` and `Biprojectable` type classes have been introduced. These classes model a type of functors and bifunctors (respectively) on tables, where the mapping function is only able to rearrange columns. For example, the following is now possible:
101+
102+ ```haskell
103+ x <- project myTableX <$> many ...
104+ ```
105+
106+* `Insert`'s `onConflict` field now has a new option - `DoUpdate`. This maps to PostgreSQL's `ON CONFLICT DO UPDATE` syntax, which provides upsert support. ([#85](https://github.com/circuithub/rel8/pull/85))
107+
108+* `Insert`, `Update` and `Delete` has all been expanded to work with `Query`s. In particular:
109+
110+ * `Delete` now supports a `USING` sub-query
111+ * `Update` now supports a `FROM` sub-query
112+ * `Insert` can delete the result of any arbitrary `Query` (providing the types match)
113+
114+* The new `Rel8.Tabulate` module has been added, which gives a `Map`-esque interface to writing and composing queries. ([#70](https://github.com/circuithub/rel8/pull/70))
115+
116+* The new `indexed` `Query -> Query` function was added. This function augments each row in a query with it's 0-based index. ([#117](https://github.com/circuithub/rel8/pull/117))
117+
118+## Breaking changes
119+
120+* `Insert`, `Delete` and `Update` have all changed. In particular, for `Insert` users should now replace `rows = xs` with `rows = values xs`. ([#85](https://github.com/circuithub/rel8/pull/85))
121+
122+* Rename `whereExists` and `whereNotExists` to `present` and `absent` respectively. ([#57](https://github.com/circuithub/rel8/pull/57))
123+
124+* Simplify `evaluate` to run directly inside the `Query` monad, rendering the `Evaluate` monad unnecessary. ([#56](https://github.com/circuithub/rel8/pull/56))
125+
126+* The `Labelable` type class has been removed as it's no longer necessary. This class was mostly internal, though was visible in some public API functions. ([#76](https://github.com/circuithub/rel8/pull/76))
127+
128+* `EitherTable`, `ListTable`, `MaybeTable`, `NonEmptyTable` and `TheseTable` now all have an extra parameter which tracks the context of the table. If you manually specified any types before, you need to provide this parameter - usually `Expr` will be the correct choice. ([#101](https://github.com/circuithub/rel8/pull/101))
129+
130+* We've done a lot of work to simplify the internals of Rel8, but some of these are breaking changes. However, most of these API changes shouldn't affect users as they are mostly types used in type inference, or affect classes where users don't need to define their own instances.
131+
132+ * The kind of a `Rel8able` is now `(Type -> Type) -> Type`. Previously it was `(X -> Type) -> Type`.
133+ * `Table` has a new associated type - `FromExprs`. This was previously an open type family.
134+ * `Table` has a new associated type - `Transpose` - and `Recontextualise` has been renamed to `Transposes`. This `Transposes` class now operates in terms of `Transpose`.
135+
136+* `select`, `insert`, `update` and `delete` now produce Hasql `Statement`s, rather than actually running the statement as IO. This allows Rel8 to be used with transaction/connection-managing monads like [`hasql-transaction`](https://hackage.haskell.org/package/hasql-transaction). ([#94](https://github.com/circuithub/rel8/pull/94))
137+
138+## Bug fixes
139+
140+* Fixes a bug where cartesian products of queries using `catListTable`, `catNonEmptyTable`, `catList` and `catNonEmpty` would incorrectly be zipped instead. ([#61](https://github.com/circuithub/rel8/pull/61))
141+
142+* Require Opaleye 0.7.3.0. This version has better support for lateral queries, which can improve query plans, especially in `optional`/`LEFT JOIN` ([#72](https://github.com/circuithub/rel8/pull/72))
143+
144+* Rel8 now compiles with GHC 9. ([#97](https://github.com/circuithub/rel8/pull/97))
145+
146+## Other changes
147+
148+* `exists` is now implemented in terms of the SQL `EXISTS` keyword. ([#69](https://github.com/circuithub/rel8/pull/69))
149+
150+* `alignBy` no longer requires `Table`s. ([#67](https://github.com/circuithub/rel8/pull/67))
151+
152+
153+# 1.0.0.1 (2021-06-21)
154+
155+This release contains various fixes for documentation.
156+
157+# 1.0.0.0 (2021-06-18)
158+
159+* Initial release.
LICENSE+1−1
@@ -1,4 +1,4 @@
1−Copyright 2020 Oliver Charles
1+Copyright 2021 Oliver Charles
22
33All rights reserved.
44
README.md+4
@@ -10,4 +10,8 @@ The main objectives of Rel8 are:
1010
1111* *Familiar*: writing Rel8 queries should feel like normal Haskell programming.
1212
13+Rel8 was presented at ZuriHac 2021. If you want to have a brief overview of what Rel8 is, and a tour of the API - check out the video below:
14+
15+[![Rel8 presentation at ZuriHac 2021](https://img.youtube.com/vi/3uwrtjxiq6E/hqdefault.jpg)](http://www.youtube.com/watch?v=3uwrtjxiq6E)
16+
1317For more details, check out the [official documentation](https://rel8.readthedocs.io/en/latest/).
cabal.project−5
@@ -1,6 +1 @@
11packages: .
2−
3−allow-newer: generic-monoid:base
4−allow-newer: cryptohash-sha1:base
5−allow-newer: cryptohash-md5:base
6−allow-newer: entropy:Cabal
cabal.project.haskell-nix−6
@@ -2,9 +2,3 @@
22-- will interpret them as local packages, and try to build them when we cabal
33-- build. The only reason we have to specify these is for Haskell.nix to know to
44-- override these packages by fetching them rather than using Hackage.
5−
6−source-repository-package
7− type: git
8− location: git://github.com/jcpetruzza/barbies
9− tag: f99b05454874192e3511bd133555dfb6cc6a6ecb
10− --sha256: 0yy2i2jbllwavv5d2176rf8lmm4l1ws90lxkmdlfgvfzqxidx0gi
default.nix+5−5
@@ -1,15 +1,15 @@
1−let
1+let
22 haskellNix = import (import ./nix/sources.nix)."haskell.nix" {};
33
4− nixpkgsSrc = haskellNix.sources.nixpkgs-2009;
4+ nixpkgsSrc = haskellNix.sources.nixpkgs-unstable;
55
66 nixpkgsArgs = haskellNix.nixpkgsArgs;
77
8− compiler-nix-name = "ghc8104";
8+ compiler-nix-name = "ghc924";
99
1010 pkgs = import nixpkgsSrc nixpkgsArgs;
1111
12−in
12+in
1313pkgs.haskell-nix.project {
1414 inherit compiler-nix-name;
1515
@@ -20,7 +20,7 @@ pkgs.haskell-nix.project {
2020 src = ./.;
2121 };
2222
23− modules = [
23+ modules = [
2424 { packages.rel8 = {
2525 preCheck = ''
2626 export PATH="${pkgs.postgresql}/bin:${"$PATH"}"
docs/concepts/dbtype.rst+18−17
@@ -11,18 +11,19 @@ though most of these primitive ``DBType``\s should already be available.
1111Combining ``newtype`` and ``DBType``
1212------------------------------------
1313
14−You can define new instances of ``DBType`` by using Haskell "generalized newtype
15−deriving" strategy. This is useful when you have a common database type, but
16−need to interpret this type differently in different contexts. A very common
17−example here is with auto-incrementing ``id`` counters. In PostgreSQL, it's
18−common for a table to have a primary key that uses the ``serial`` type, which
19−means the key is an ``int8`` with a default value for ``INSERT``. In Rel8, we
20−could use ``Int64`` (as ``Int64`` is the ``DBType`` instance for ``int8``), but
21−we can be even clearer if we make a ``newtype`` for each *type* of id.
22−
23−If our database has users and orders, these tables might both have ids, but they
24−are clearly not meant to be treated as a common type. Instead, we can make these
25−types clearly different by writing::
14+You can define new instances of ``DBType`` by using Haskell "generalized
15+newtype deriving" strategy. This is useful when you have a common database
16+type, but need to interpret this type differently in different contexts. A very
17+common example here is with auto-incrementing ``id`` counters. In PostgreSQL,
18+it's common for a table to have a primary key that uses the ``serial`` type,
19+which means the key is an ``int8`` with a default value for ``INSERT``. In
20+Rel8, we could use ``Int64`` (as ``Int64`` is the ``DBType`` instance for
21+``int8``), but we can be even clearer if we make a ``newtype`` for each *type*
22+of id.
23+
24+If our database has users and orders, these tables might both have ids, but
25+they are clearly not meant to be treated as a common type. Instead, we can make
26+these types clearly different by writing::
2627
2728 newtype UserId = UserId { getUserId :: Int64 }
2829 deriving newtype DBType
@@ -57,8 +58,8 @@ In our PostgreSQL we have a few choices, but for now we'll assume that they are
5758stored as ``text`` values.
5859
5960In order to use this type in Rel8 queries, we need to write an instance of
60−``DBType`` for ``OrderStatus``. One approach is to use ``parseTypeInformation``,
61−which allows you to refine an existing ``DBType``::
61+``DBType`` for ``OrderStatus``. One approach is to use
62+``parseTypeInformation``, which allows you to refine an existing ``DBType``::
6263
6364 instance DBType OrderStatus where
6465 typeInformation = parseTypeInformation parser printer typeInformation
@@ -100,9 +101,9 @@ There usage is very similar to ``ReadShow`` - simply derive ``DBType via
100101JSONEncoded``, and Rel8 will use ``ToJSON`` and ``FromJSON`` instances (from
101102``aeson``) to serialize the given type.
102103
103−For example, a project might use event sourcing with a table of events. Each row
104−in this table is an event, but this event is stored as a JSON object. We can use
105−this type with Rel8 by writing::
104+For example, a project might use event sourcing with a table of events. Each
105+row in this table is an event, but this event is stored as a JSON object. We
106+can use this type with Rel8 by writing::
106107
107108 data Event = UserCreated UserCreatedData | OrderCreated OrderCreatedData
108109 deriving stock Generic
docs/concepts/expr.rst+2−2
@@ -58,7 +58,7 @@ Through the API reference documentation for Rel8, you might encounter the
5858``Sql`` type class. For example, if we look at the type of ``litExpr``, we
5959have::
6060
61− litExpr :: Sql DBType a => a -> Expr a
61+ litExpr :: Sql DBType a => a -> Expr a
6262
6363Here ``Sql DBType a`` means that ``a`` can either be literally a type that has
6464an instance of ``DBType`` (like ``UserId`` or ``Bool``), *or* that same type
@@ -69,6 +69,6 @@ Some functions work regardless of whether or not a value is null, and in these
6969cases you'll see ``Sql DBType a``. ``Sql`` can be used with any ``DBType``
7070subtype. For example, the type of ``div`` is::
7171
72− div :: Sql DBIntegral a => Expr a -> Expr a -> Expr a
72+ div :: Sql DBIntegral a => Expr a -> Expr a -> Expr a
7373
7474Which means ``div`` works on any ``DBIntegral a``, including ``Maybe a``.
docs/concepts/insert.rstnew file+181
@@ -0,0 +1,181 @@
1+``INSERT``, ``UPDATE`` and ``DELETE``
2+=====================================
3+
4+While the majority of Rel8 is about building and executing ``SELECT``
5+statement, Rel8 also has support for ``INSERT``, ``UPDATE`` and ``DELETE``.
6+These statements are all executed using the ``insert``, ``update`` and
7+``delete`` functions, all of which take a record of parameters.
8+
9+.. note::
10+
11+ This part of Rel8's API uses the ``DuplicateRecordFields`` language
12+ extension. In code that needs to use this API, you should also enable this
13+ language extension, or you may get errors about ambiguous field names.
14+
15+``DELETE``
16+----------
17+
18+To perform a ``DELETE`` statement, construct a ``Delete`` value and execute it
19+using ``delete``. ``Delete`` takes:
20+
21+``from``
22+ The ``TableSchema`` for the table to delete rows from.
23+
24+``using``
25+ This is a simple ``Query`` that forms the ``USING`` clause of the ``DELETE``
26+ statement. This can be used to join against other tables, and the results
27+ can be referenced in the ``deleteWhere`` parameter. For simple ``DELETE``\s
28+ where you don't need to do this, you can set ``using = pure ()``.
29+
30+``deleteWhere``
31+ The ``WHERE`` clause of the ``DELETE`` statement. This is a function that
32+ takes two inputs: the result of the ``using`` query, and the current value
33+ of the row.
34+
35+``returning``
36+ What to return - see :ref:`returning`.
37+
38+``UPDATE``
39+----------
40+
41+To perform a ``UPDATE`` statement, construct a ``Update`` value and execute it
42+using ``update``. ``Update`` takes:
43+
44+``target``
45+ The ``TableSchema`` for the table to update rows in.
46+
47+``from``
48+ This is a simple ``Query`` that forms the ``FROM`` clause of the ``UPDATE``
49+ statement. This can be used to join against other tables, and the results
50+ can be referenced in the ``set`` and ``updateWhere`` parameters. For simple
51+ ``UPDATE``\s where you don't need to do this, you can set ``from = pure ()``.
52+
53+``set``
54+ A row to row transformation function, indicating how to update selected rows.
55+ This function takes rows of the same shape as ``target`` but in the ``Expr``
56+ context. One way to write this function is to use record update syntax::
57+
58+ set = \from row -> row { rowName = "new name" }
59+
60+``updateWhere``
61+ The ``WHERE`` clause of the ``UPDATE`` statement. This is a function that
62+ takes two inputs: the result of the ``from`` query, and the current value of
63+ the row.
64+
65+``returning``
66+ What to return - see :ref:`returning`.
67+
68+``INSERT``
69+----------
70+
71+To perform a ``INSERT`` statement, construct a ``Insert`` value and execute it
72+using ``insert``. ``Insert`` takes:
73+
74+``into``
75+ The ``TableSchema`` for the table to insert rows into.
76+
77+``rows``
78+ The rows to insert. These are the same as ``into``, but in the ``Expr``
79+ context. You can construct rows from their individual fields::
80+
81+ rows = values [ MyTable { myTableA = lit "A", myTableB = lit 42 }
82+
83+ or you can use ``lit`` on a table value in the ``Result`` context::
84+
85+ rows = values [ lit MyTable { myTableA = "A", myTableB = 42 }
86+
87+``onConflict``
88+ What should happen if an insert clashes with rows that already exist. This
89+ corresponds to PostgreSQL's ``ON CONFLICT`` clause. You can specify:
90+
91+ ``Abort``
92+ PostgreSQL should abort the ``INSERT`` with an exception
93+
94+ ``DoNothing``
95+ PostgreSQL should not insert the duplicate rows.
96+
97+ ``DoUpdate``
98+ PostgreSQL should instead try to update any existing rows that conflict
99+ with rows proposed for insertion.
100+
101+``returning``
102+ What to return - see :ref:`returning`.
103+
104+.. _returning:
105+
106+``RETURNING``
107+-------------
108+
109+PostgreSQL has the ability to return extra information after a ``DELETE``,
110+``INSERT`` or ``UPDATE`` statement by attaching a ``RETURNING`` clause. A common
111+use of this clause is to return any automatically generated sequence values for
112+primary key columns. Rel8 supports ``RETURNING`` clauses by filling in the
113+``returning`` field and specifying a ``Projection``. A ``Projection`` is a row
114+to row transformation, allowing you to project out a subset of fields.
115+
116+For example, if we are inserting orders, we might want the order ids returned::
117+
118+ insert Insert
119+ { into = orderSchema
120+ , rows = values [ order ]
121+ , onConflict = Abort
122+ , returning = Projection orderId
123+ }
124+
125+If we don't want to return anything, we can use ``pure ()``::
126+
127+ insert Insert
128+ { into = orderSchema
129+ , rows = values [ order ]
130+ , onConflict = Abort
131+ , returning = pure ()
132+ }
133+
134+Default values
135+--------------
136+
137+It is fairly common to define tables with default values. While Rel8 does not
138+have specific functionality for ``DEFAULT``, there are a few options:
139+
140+``unsafeDefault``
141+~~~~~~~~~~~~~~~~~~~~~~~~~~~
142+
143+Rel8 does not have any special support for ``DEFAULT``. If you need to use
144+default column values in inserts, you can use ``unsafeDefault`` to
145+construct the ``DEFAULT`` expression::
146+
147+ insert Insert
148+ { into = orderSchema
149+ , rows = values [ Order { orderId = unsafeDefault, ... } ]
150+ , onConflict = Abort
151+ , returning = Projection orderId
152+ }
153+
154+.. warning::
155+ As the name suggests, this is an unsafe operation. In particular, Rel8 is not
156+ able to prove that this column does have a default value, so it may be
157+ possible to introduce a runtime error. Furthermore, ``DEFAULT`` is fairly
158+ special in SQL, and cannot be combined like other expressions. For example,
159+ the innocuous expression::
160+
161+ unsafeDefault + 1
162+
163+ will lead to a runtime crash.
164+
165+Reimplement default values in Rel8
166+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
167+
168+If you only need to access default values in Rel8, another option is to specify
169+them in Rel8, rather than in your database schema.
170+
171+.. hint::
172+ A common default value for primary keys is to use `nextval` to obtain the
173+ next value from a sequence. This can be done in Rel8 by using the ``nextval``
174+ function::
175+
176+ insert Insert
177+ { into = orderSchema
178+ , rows = values [ Order { orderId = nextval "order_id_seq", ... } ]
179+ , onConflict = Abort
180+ , returning = Projection orderId
181+ }
docs/concepts/queries.rst+9−9
@@ -88,7 +88,7 @@ notation allows you to write these queries in a simpler form, where we don't
8888have to introduce functions. Expanding on the latter query, we could write::
8989
9090 do user <- getAllUsers
91− order <- getOrdersForUser (user)
91+ order <- getOrdersForUser user
9292 return (user, order)
9393
9494Now we have a query that, for each ``User``, fetches all orders for that user.
@@ -138,20 +138,20 @@ a query. The above query could thus be written as::
138138
139139``where_`` and ``filter`` allow you to filter rows based on an expression, but
140140sometimes we want to filter based on another query. For this, Rel8 offers
141−``whereExists`` and ``whereNotExists``. For example, if all blog posts have a
142−list of tags, we could use ``whereExists`` to find all blog posts that have been
141+``present`` and ``absent``. For example, if all blog posts have a
142+list of tags, we could use ``present`` to find all blog posts that have been
143143tagged as "Haskell"::
144144
145145 blogPost <- each blogPostSchema
146− whereExists do
146+ present do
147147 filter (("Haskell" ==.) . tagName) =<< tagFromBlogPost blogPost
148148
149−Notice that this example uses ``whereExists`` with a query that itself uses
150−``filter``. For each blog post, ``whereExists`` causes that row to be selected
149+Notice that this example uses ``present`` with a query that itself uses
150+``filter``. For each blog post, ``present`` causes that row to be selected
151151only if the associated query finds a tag for that blog post with the ``tagName``
152152"Haskell".
153153
154−Like ``filter`` there is also a chaining variant of ``whereExists`` - ``with``.
154+Like ``filter`` there is also a chaining variant of ``present`` - ``with``.
155155We could rewrite the above query using ``with`` as::
156156
157157 haskellBlogPost <-
@@ -194,11 +194,11 @@ and this query can be written in Rel8 as::
194194
195195 authorForBlogPost :: BlogPost Expr -> Query (Author Expr)
196196 authorForBlogPost blogPost =
197− filter ((blogPostAuthorId blogPost ==.) authorId author) =<<
197+ filter ((blogPostAuthorId blogPost ==.) . authorId) =<<
198198 each authorSchema
199199
200200 While this is a little more code over all, in our experience this style
201− dramatically increases the readabality of queries using joins.
201+ dramatically increases the readability of queries using joins.
202202
203203Left (outer) joins with ``optional``
204204------------------------------------
docs/cookbook.rst+10−8
@@ -72,7 +72,7 @@ can be written as::
7272 each myTableSchema
7373
7474Note that we use ``>$<`` (from ``Data.Functor.Contravariant``) to select table
75−columns, and we can use `mconcat` to combine orderings.
75+columns, and we can use ``mconcat`` to combine orderings.
7676
7777If all columns of a table have an ordering, you can also use ``ascTable`` and
7878``descTable``. For example::
@@ -142,23 +142,25 @@ rows, but can also return *tree*\s.
142142To understand what this means, we'll consider a small example query for blog
143143posts. We want our query to return:
144144
145−1. The latest 5 blog posts.
145+1. The latest 5 blog posts that have at least one tag each.
1461462. For each blog post, all tags.
147−3. For each blog post, the latest 3 comments.
147+3. For each blog post, the latest 3 comments if they exist.
148148
149149In Rel8, we can write this query as::
150150
151151 latestBlogPosts = do
152152 post <- each postSchema
153153
154− tags <- aggregate do
154+ -- Returns a `NonEmptyTable a` which ends up as a `Data.List.NonEmpty a` after the query is run
155+ tags <- some $ do
155156 tag <- each tagSchema
156157 where_ (tagPostId tag ==. postId post)
157− return (listAgg (tagName tag))
158+ return (tagName tag)
158159
159− latestComments <-
160− many $
161− limit 3 $
160+ -- Returns a `ListTable a` which ends up as a `[a]` after the query is run
161+ latestComments <-
162+ many $
163+ limit 3 $
162164 orderBy (commentCreatedAt >$< desc) do
163165 comment <- each commentSchema
164166 where_ (commentPostId comment ==. postId post)
docs/index.rst+2−1
@@ -30,6 +30,7 @@ The main objectives of Rel8 are:
3030 concepts/expr
3131 concepts/tables
3232 concepts/queries
33+ concepts/insert
3334
3435.. toctree::
3536 :caption: Tips and tricks
@@ -49,4 +50,4 @@ More Resources
4950
5051* If you think you've found a bug, confusing behavior, or have a feature
5152 request, please raise an issue at `Rel8's issue tracker
52− <https://github.com/circuithub/rel8>`_.
53+ <https://github.com/circuithub/rel8>`_.
docs/tutorial.rst+64−47
@@ -5,24 +5,25 @@ Getting Started
55
66In this section, we'll take a look at using Rel8 to work with a small database
77for Haskell packages. We'll take a look at idiomatic usage of Rel8, mapping
8−tables to Haskell, and then look at writing some simple queries.
8+tables to Haskell, and then look at writing some simple queries.
99
1010Before we get started, we'll be using the following language extensions and
1111imports throughout this guide::
1212
13− {-# language -XBlockArguments #-}
14− {-# language -XDeriveAnyClass #-}
15− {-# language -XDeriveGeneric #-}
16− {-# language -XDerivingStrategies #-}
17− {-# language -XDerivingVia #-}
18− {-# language -XDuplicateRecordFields #-}
19− {-# language -XGeneralizedNewtypeDeriving #-}
20− {-# language -XOverloadedStrings #-}
21− {-# language -XStandaloneDeriving #-}
22− {-# language -XTypeApplications #-}
23− {-# language -XTypeFamilies #-}
13+ {-# language BlockArguments #-}
14+ {-# language DeriveAnyClass #-}
15+ {-# language DeriveGeneric #-}
16+ {-# language DerivingStrategies #-}
17+ {-# language DerivingVia #-}
18+ {-# language DuplicateRecordFields #-}
19+ {-# language GeneralizedNewtypeDeriving #-}
20+ {-# language OverloadedStrings #-}
21+ {-# language StandaloneDeriving #-}
22+ {-# language TypeApplications #-}
23+ {-# language TypeFamilies #-}
2424
2525 import Prelude
26+ import Rel8
2627
2728The Example Schema
2829------------------
@@ -70,7 +71,7 @@ Following these steps for ``author``, we have::
7071 { authorId :: Column f Int64
7172 , name :: Column f Text
7273 , url :: Column f (Maybe Text)
73− }
74+ }
7475 deriving stock (Generic)
7576 deriving anyclass (Rel8able)
7677
@@ -81,7 +82,7 @@ in our project, it would be too easy to accidentally mix them up and create
8182nonsensical joins. As Haskell programmers, we often solve this problem by
8283creating ``newtype`` wrappers, and we can also use this technique with Rel8::
8384
84− newtype AuthorId = AuthorId { toInt64 :: Int64 }
85+ newtype AuthorId = AuthorId { toInt64 :: Int64 }
8586 deriving newtype (DBEq, DBType, Eq, Show)
8687
8788Now we can write our final schema mapping. First, the ``author`` table::
@@ -90,7 +91,7 @@ Now we can write our final schema mapping. First, the ``author`` table::
9091 { authorId :: Column f AuthorId
9192 , authorName :: Column f Text
9293 , authorUrl :: Column f (Maybe Text)
93− }
94+ }
9495 deriving stock (Generic)
9596 deriving anyclass (Rel8able)
9697
@@ -99,16 +100,16 @@ And similarly, the ``project`` table::
99100 data Project f = Project
100101 { projectAuthorId :: Column f AuthorId
101102 , projectName :: Column f Text
102− }
103+ }
103104 deriving stock (Generic)
104− deriving anyclass (Rel8able
105+ deriving anyclass (Rel8able)
105106
106107To show query results in this documentation, we'll also need ``Show`` instances:
107108Unfortunately these definitions look a bit scary, but they are essentially just
108109``deriving (Show)``::
109110
110− deriving stock instance f ~ Identity => Show (Author f)
111− deriving stock instance f ~ Identity => Show (Project f)
111+ deriving stock instance f ~ Result => Show (Author f)
112+ deriving stock instance f ~ Result => Show (Project f)
112113
113114These data types describe the structural mapping of the tables, but we also
114115need to specify a ``TableSchema`` for each table. A ``TableSchema`` contains
@@ -125,9 +126,9 @@ associated with the ``Author`` type::
125126
126127 authorSchema :: TableSchema (Author Name)
127128 authorSchema = TableSchema
128− { tableName = "author"
129− , tableSchema = Nothing
130− , tableColumns = Author
129+ { name = "author"
130+ , schema = Nothing
131+ , columns = Author
131132 { authorId = "author_id"
132133 , authorName = "name"
133134 , authorUrl = "url"
@@ -138,14 +139,27 @@ And likewise for ``project`` and ``Project``::
138139
139140 projectSchema :: TableSchema (Project Name)
140141 projectSchema = TableSchema
141− { tableName = "project"
142− , tableSchema = Nothing
143− , tableColumns = Project
142+ { name = "project"
143+ , schema = Nothing
144+ , columns = Project
144145 { projectAuthorId = "author_id"
145146 , projectName = "name"
146147 }
147148 }
148149
150+There is also some generics machinery available if you want to grab the field
151+information from your ``Rel8able`` type::
152+
153+ projectSchema :: TableSchema (Project Name)
154+ projectSchema = TableSchema
155+ { name = "project"
156+ , schema = Nothing
157+ , columns = namesFromLabels @(Project Name)
158+ }
159+
160+This will create a ``TableSchema`` for ``Project`` where every column name
161+corresponds exactly to the name of the field. If you need more flexibility, you
162+can use ``namesFromLabelsWith``, which takes a transformation function.
149163
150164.. note::
151165
@@ -169,7 +183,7 @@ database heavy applications.
169183
170184In Rel8, ``SELECT`` statements are built using the ``Query`` monad. You can
171185think of this monad like the ordinary ``[]`` (List) monad - but this isn't
172−required knowledge.
186+required knowledge.
173187
174188To start, we'll look at one of the simplest queries possible - a basic ``SELECT
175189* FROM`` statement. To select all rows from a table, we use ``each``, and
@@ -190,25 +204,28 @@ Recall we defined ``projectAuthorId`` as ``Column f AuthorId``. Now we have
190204We'll see more about ``Expr`` soon, but you can think of ``Expr a`` as "SQL
191205expressions of type ``a``\".
192206
193−To execute this ``Query``, we pass it to ``select``::
207+To execute this ``Query``, we pass it to ``select``. This function takes both a
208+database connection (which can be obtained using hasql's ``acquire`` function),
209+and the ``Query`` to run::
194210
195− >>> :t select c (each projectSchema)
196− select c (each projectSchema) :: MonadIO m => m [Project Identity]
211+ >>> Right conn <- acquire "user=postgres"
212+ >>> :t select conn (each projectSchema)
213+ select conn (each projectSchema) :: MonadIO m => m [Project Result]
197214
198−When we ``select`` things containing ``Expr``s, Rel8 builds a new response
199−table with the ``Identity`` interpretation. This means you'll get back plain
215+When we ``select`` things containing ``Expr``\s, Rel8 builds a new response
216+table with the ``Result`` interpretation. This means you'll get back plain
200217Haskell values. Studying ``projectAuthorId`` again, we have::
201218
202− >>> let aProjectIdentity = undefined :: Project Identity
203− >>> :t projectAuthorId aProjectIdentity
204− projectAuthorId aProjectIdentity :: AuthorId
219+ >>> let aProjectResult = undefined :: Project Result
220+ >>> :t projectAuthorId aProjectResult
221+ projectAuthorId aProjectResult :: AuthorId
205222
206−Here ``Column Identity AuthorId`` reduces to just ``AuthorId``, with no
223+Here ``Column Result AuthorId`` reduces to just ``AuthorId``, with no
207224wrappping type at all.
208225
209226Putting this all together, we can run our first query::
210227
211− >>> select c (each projectSchema) >>= mapM_ print
228+ >>> select conn (each projectSchema) >>= mapM_ print
212229 Project {projectAuthorId = 1, projectName = "rel8"}
213230 Project {projectAuthorId = 2, projectName = "aeson"}
214231 Project {projectAuthorId = 2, projectName = "text"}
@@ -218,7 +235,7 @@ sometimes we're only interested in a subset of the columns of a table. To
218235restrict the returned columns, we can specify a projection by using ``Query``\s
219236``Functor`` instance::
220237
221− >>> select c $ projectName <$> each projectSchema
238+ >>> select conn $ projectName <$> each projectSchema
222239 ["rel8","aeson","text"]
223240
224241Joins
@@ -234,7 +251,7 @@ We can do this by simply calling ``each`` twice, and then returning a tuple of
234251their results::
235252
236253 >>> :{
237− mapM_ print =<< select c do
254+ mapM_ print =<< select conn do
238255 author <- each authorSchema
239256 project <- each projectSchema
240257 return (projectName project, authorName author)
@@ -253,7 +270,7 @@ This isn't quite right, though, as we have ended up pairing up the wrong
253270projects and authors. To fix this, we can use ``where_`` to restrict the
254271returned rows. We could write::
255272
256− select c $ do
273+ select conn $ do
257274 author <- each authorSchema
258275 project <- each projectSchema
259276 where_ $ projectAuthorId project ==. authorId author
@@ -270,7 +287,7 @@ for the particular joins in your database. In our case, this would be::
270287Our final query is then::
271288
272289 >>> :{
273− mapM_ print =<< select c do
290+ mapM_ print =<< select conn do
274291 author <- each authorSchema
275292 project <- projectsForAuthor author
276293 return (projectName project, authorName author)
@@ -289,7 +306,7 @@ transformer to allow for the possibility of the join to fail.
289306In our test database, we can see that there's another author who we haven't
290307seen yet::
291308
292− >>> select c $ authorName <$> each authorSchema
309+ >>> select conn $ authorName <$> each authorSchema
293310 ["Ollie","Bryan O'Sullivan","Emily Pillmore"]
294311
295312Emily wasn't returned in our earlier query because - in our database - she
@@ -297,7 +314,7 @@ doesn't have any registered projects. We can account for this partiality in our
297314original query by wrapping the ``projectsForAuthor`` call with ``optional``::
298315
299316 >>> :{
300− mapM_ print =<< select c do
317+ mapM_ print =<< select conn do
301318 author <- each authorSchema
302319 mproject <- optional $ projectsForAuthor author
303320 return (authorName author, projectName <$> mproject)
@@ -342,9 +359,9 @@ focus on the /type/ of that query::
342359 return (author, project)
343360 where
344361
345− >>> :t select c authorsAndProjects
346− select c authorsAndProjects
347− :: MonadIO m => m [(Author Identity, Project Identity)]
362+ >>> :t select conn authorsAndProjects
363+ select conn authorsAndProjects
364+ :: MonadIO m => m [(Author Result, Project Result)]
348365
349366
350367Our query gives us a single list of pairs of authors and projects. However,
@@ -352,7 +369,7 @@ with our domain knowledge of the schema, this isn't a great type - what we'd
352369rather have is a list of pairs of authors and /lists/ of projects. That is,
353370what we'd like is::
354371
355− [(Author Identity, [Project Identity])]
372+ [(Author Result, [Project Result])]
356373
357374This would be a much better type! Rel8 can produce a query with this type by
358375simply wrapping the call to ``projectsForAuthor`` with either ``some`` or
@@ -360,7 +377,7 @@ simply wrapping the call to ``projectsForAuthor`` with either ``some`` or
360377author to have no projects::
361378
362379 >>> :{
363− mapM_ print =<< select c do
380+ mapM_ print =<< select conn do
364381 author <- each authorSchema
365382 projectNames <- many $ projectName <$> projectsForAuthor author
366383 return (authorName author, projectNames)
nix/sources.json+9−9
@@ -5,10 +5,10 @@
55 "homepage": "https://input-output-hk.github.io/haskell.nix",
66 "owner": "input-output-hk",
77 "repo": "haskell.nix",
8− "rev": "5b5a18e442df6e27ad8549d69b8868b62adb08c3",
9− "sha256": "055mk7kmjppng66ppnb8kr96v4wwc8pcxfsls5gl77129hsz9aph",
8+ "rev": "0837156c56cb5350dd9bd84eb424187e00aa1e8a",
9+ "sha256": "1djmv5a0vfj78csw2cad6nicrs8iqrp928b9b3v4h7lwwhhzliwl",
1010 "type": "tarball",
11− "url": "https://github.com/input-output-hk/haskell.nix/archive/5b5a18e442df6e27ad8549d69b8868b62adb08c3.tar.gz",
11+ "url": "https://github.com/input-output-hk/haskell.nix/archive/0837156c56cb5350dd9bd84eb424187e00aa1e8a.tar.gz",
1212 "url_template": "https://github.com/<owner>/<repo>/archive/<rev>.tar.gz"
1313 },
1414 "niv": {
@@ -17,10 +17,10 @@
1717 "homepage": "https://github.com/nmattia/niv",
1818 "owner": "nmattia",
1919 "repo": "niv",
20− "rev": "af958e8057f345ee1aca714c1247ef3ba1c15f5e",
21− "sha256": "1qjavxabbrsh73yck5dcq8jggvh3r2jkbr6b5nlz5d9yrqm9255n",
20+ "rev": "acdb1726783637852c01e0ad639ac9cbec28d8c8",
21+ "sha256": "1wszl8q70z6wfgkh2dvgmhhry6qp9nar421qq2ifd17hq2jj9ck3",
2222 "type": "tarball",
23− "url": "https://github.com/nmattia/niv/archive/af958e8057f345ee1aca714c1247ef3ba1c15f5e.tar.gz",
23+ "url": "https://github.com/nmattia/niv/archive/acdb1726783637852c01e0ad639ac9cbec28d8c8.tar.gz",
2424 "url_template": "https://github.com/<owner>/<repo>/archive/<rev>.tar.gz"
2525 },
2626 "nixpkgs": {
@@ -29,10 +29,10 @@
2929 "homepage": null,
3030 "owner": "nixos",
3131 "repo": "nixpkgs",
32− "rev": "a6847cb5460b47241eb35d1a6588652411642066",
33− "sha256": "0wb5hwgffr4in66qng22sfvbascwnq078q81ziwwayvmnkn73rrm",
32+ "rev": "1c1f5649bb9c1b0d98637c8c365228f57126f361",
33+ "sha256": "0f2nvdijyxfgl5kwyb4465pppd5vkhqxddx6v40k2s0z9jfhj0xl",
3434 "type": "tarball",
35− "url": "https://github.com/nixos/nixpkgs/archive/a6847cb5460b47241eb35d1a6588652411642066.tar.gz",
35+ "url": "https://github.com/nixos/nixpkgs/archive/1c1f5649bb9c1b0d98637c8c365228f57126f361.tar.gz",
3636 "url_template": "https://github.com/<owner>/<repo>/archive/<rev>.tar.gz"
3737 }
3838}
nix/sources.nix+66−20
@@ -6,25 +6,53 @@ let
66 # The fetchers. fetch_<type> fetches specs of type <type>.
77 #
88
9− fetch_file = pkgs: spec:
10− if spec.builtin or true then
11− builtins_fetchurl { inherit (spec) url sha256; }
12− else
13− pkgs.fetchurl { inherit (spec) url sha256; };
9+ fetch_file = pkgs: name: spec:
10+ let
11+ name' = sanitizeName name + "-src";
12+ in
13+ if spec.builtin or true then
14+ builtins_fetchurl { inherit (spec) url sha256; name = name'; }
15+ else
16+ pkgs.fetchurl { inherit (spec) url sha256; name = name'; };
1417
1518 fetch_tarball = pkgs: name: spec:
1619 let
17− ok = str: ! builtins.isNull (builtins.match "[a-zA-Z0-9+-._?=]" str);
18− # sanitize the name, though nix will still fail if name starts with period
19− name' = stringAsChars (x: if ! ok x then "-" else x) "${name}-src";
20+ name' = sanitizeName name + "-src";
2021 in
2122 if spec.builtin or true then
2223 builtins_fetchTarball { name = name'; inherit (spec) url sha256; }
2324 else
2425 pkgs.fetchzip { name = name'; inherit (spec) url sha256; };
2526
26− fetch_git = spec:
27− builtins.fetchGit { url = spec.repo; inherit (spec) rev ref; };
27+ fetch_git = name: spec:
28+ let
29+ ref =
30+ if spec ? ref then spec.ref else
31+ if spec ? branch then "refs/heads/${spec.branch}" else
32+ if spec ? tag then "refs/tags/${spec.tag}" else
33+ abort "In git source '${name}': Please specify `ref`, `tag` or `branch`!";
34+ submodules = if spec ? submodules then spec.submodules else false;
35+ submoduleArg =
36+ let
37+ nixSupportsSubmodules = builtins.compareVersions builtins.nixVersion "2.4" >= 0;
38+ emptyArgWithWarning =
39+ if submodules == true
40+ then
41+ builtins.trace
42+ (
43+ "The niv input \"${name}\" uses submodules "
44+ + "but your nix's (${builtins.nixVersion}) builtins.fetchGit "
45+ + "does not support them"
46+ )
47+ {}
48+ else {};
49+ in
50+ if nixSupportsSubmodules
51+ then { inherit submodules; }
52+ else emptyArgWithWarning;
53+ in
54+ builtins.fetchGit
55+ ({ url = spec.repo; inherit (spec) rev; inherit ref; } // submoduleArg);
2856
2957 fetch_local = spec: spec.path;
3058
@@ -40,11 +68,21 @@ let
4068 # Various helpers
4169 #
4270
71+ # https://github.com/NixOS/nixpkgs/pull/83241/files#diff-c6f540a4f3bfa4b0e8b6bafd4cd54e8bR695
72+ sanitizeName = name:
73+ (
74+ concatMapStrings (s: if builtins.isList s then "-" else s)
75+ (
76+ builtins.split "[^[:alnum:]+._?=-]+"
77+ ((x: builtins.elemAt (builtins.match "\\.*(.*)" x) 0) name)
78+ )
79+ );
80+
4381 # The set of packages used when specs are fetched using non-builtins.
44− mkPkgs = sources:
82+ mkPkgs = sources: system:
4583 let
4684 sourcesNixpkgs =
47− import (builtins_fetchTarball { inherit (sources.nixpkgs) url sha256; }) {};
85+ import (builtins_fetchTarball { inherit (sources.nixpkgs) url sha256; }) { inherit system; };
4886 hasNixpkgsPath = builtins.any (x: x.prefix == "nixpkgs") builtins.nixPath;
4987 hasThisAsNixpkgsPath = <nixpkgs> == ./.;
5088 in
@@ -64,9 +102,9 @@ let
64102
65103 if ! builtins.hasAttr "type" spec then
66104 abort "ERROR: niv spec ${name} does not have a 'type' attribute"
67− else if spec.type == "file" then fetch_file pkgs spec
105+ else if spec.type == "file" then fetch_file pkgs name spec
68106 else if spec.type == "tarball" then fetch_tarball pkgs name spec
69− else if spec.type == "git" then fetch_git spec
107+ else if spec.type == "git" then fetch_git name spec
70108 else if spec.type == "local" then fetch_local spec
71109 else if spec.type == "builtin-tarball" then fetch_builtin-tarball name
72110 else if spec.type == "builtin-url" then fetch_builtin-url name
@@ -80,7 +118,10 @@ let
80118 saneName = stringAsChars (c: if isNull (builtins.match "[a-zA-Z0-9]" c) then "_" else c) name;
81119 ersatz = builtins.getEnv "NIV_OVERRIDE_${saneName}";
82120 in
83− if ersatz == "" then drv else ersatz;
121+ if ersatz == "" then drv else
122+ # this turns the string into an actual Nix path (for both absolute and
123+ # relative paths)
124+ if builtins.substring 0 1 ersatz == "/" then /. + ersatz else /. + builtins.getEnv "PWD" + "/${ersatz}";
84125
85126 # Ports of functions for older nix versions
86127
@@ -98,25 +139,29 @@ let
98139
99140 # https://github.com/NixOS/nixpkgs/blob/0258808f5744ca980b9a1f24fe0b1e6f0fecee9c/lib/strings.nix#L269
100141 stringAsChars = f: s: concatStrings (map f (stringToCharacters s));
142+ concatMapStrings = f: list: concatStrings (map f list);
101143 concatStrings = builtins.concatStringsSep "";
102144
145+ # https://github.com/NixOS/nixpkgs/blob/8a9f58a375c401b96da862d969f66429def1d118/lib/attrsets.nix#L331
146+ optionalAttrs = cond: as: if cond then as else {};
147+
103148 # fetchTarball version that is compatible between all the versions of Nix
104− builtins_fetchTarball = { url, name, sha256 }@attrs:
149+ builtins_fetchTarball = { url, name ? null, sha256 }@attrs:
105150 let
106151 inherit (builtins) lessThan nixVersion fetchTarball;
107152 in
108153 if lessThan nixVersion "1.12" then
109− fetchTarball { inherit name url; }
154+ fetchTarball ({ inherit url; } // (optionalAttrs (!isNull name) { inherit name; }))
110155 else
111156 fetchTarball attrs;
112157
113158 # fetchurl version that is compatible between all the versions of Nix
114− builtins_fetchurl = { url, sha256 }@attrs:
159+ builtins_fetchurl = { url, name ? null, sha256 }@attrs:
115160 let
116161 inherit (builtins) lessThan nixVersion fetchurl;
117162 in
118163 if lessThan nixVersion "1.12" then
119− fetchurl { inherit url; }
164+ fetchurl ({ inherit url; } // (optionalAttrs (!isNull name) { inherit name; }))
120165 else
121166 fetchurl attrs;
122167
@@ -135,7 +180,8 @@ let
135180 mkConfig =
136181 { sourcesFile ? if builtins.pathExists ./sources.json then ./sources.json else null
137182 , sources ? if isNull sourcesFile then {} else builtins.fromJSON (builtins.readFile sourcesFile)
138− , pkgs ? mkPkgs sources
183+ , system ? builtins.currentSystem
184+ , pkgs ? mkPkgs sources system
139185 }: rec {
140186 # The sources, i.e. the attribute set of spec name to spec
141187 inherit sources;
rel8.cabal+70−30
@@ -1,25 +1,36 @@
11cabal-version: 2.0
22name: rel8
3−version: 0.1.0.0
3+version: 1.4.0.0
44synopsis: Hey! Hey! Can u rel8?
55license: BSD3
66license-file: LICENSE
77author: Oliver Charles
88maintainer: ollie@ocharles.org.uk
9+homepage: https://github.com/circuithub/rel8
10+bug-reports: https://github.com/circuithub/rel8/issues
911build-type: Simple
12+extra-doc-files:
13+ README.md
14+ Changelog.md
15+
16+source-repository head
17+ type: git
18+ location: https://github.com/circuithub/rel8
1019
1120library
1221 build-depends:
1322 aeson
14− , base ^>= 4.14 || ^>=4.15
23+ , base ^>= 4.14 || ^>=4.15 || ^>=4.16
24+ , bifunctors
1525 , bytestring
1626 , case-insensitive
17− , casing
27+ , comonad
1828 , contravariant
19− , hasql ^>= 1.4.5.1
20− , higgledy
21− , opaleye ^>= 0.7.1.0
29+ , hasql ^>= 1.4.5.1 || ^>= 1.5.0.0 || ^>= 1.6.0.0
30+ , opaleye ^>= 0.9.6.1
31+ , pretty
2232 , profunctors
33+ , product-profunctors
2334 , scientific
2435 , semialign
2536 , semigroupoids
@@ -30,10 +41,12 @@ library
3041 default-language:
3142 Haskell2010
3243 ghc-options:
44+ -Werror=missing-methods -Werror=incomplete-patterns -Werror=missing-fields
3345 -Weverything -Wno-unsafe -Wno-safe -Wno-missing-safe-haskell-mode
3446 -Wno-missing-import-lists -Wno-prepositive-qualified-module
3547 -Wno-monomorphism-restriction
36− -Wno-missing-local-signatures
48+ -Wno-missing-local-signatures
49+ -Wno-missing-kind-signatures
3750 hs-source-dirs:
3851 src
3952 exposed-modules:
@@ -43,31 +56,48 @@ library
4356 Rel8.Expr.Time
4457 Rel8.Tabulate
4558
46− -- deprecated
47− Rel8.Aggregate.Legacy
48−
4959 other-modules:
5060 Rel8.Aggregate
5161
62+ Rel8.Column
63+ Rel8.Column.ADT
64+ Rel8.Column.Either
65+ Rel8.Column.Lift
66+ Rel8.Column.List
67+ Rel8.Column.Maybe
68+ Rel8.Column.NonEmpty
69+ Rel8.Column.Null
70+ Rel8.Column.These
71+
5272 Rel8.Expr
5373 Rel8.Expr.Aggregate
5474 Rel8.Expr.Array
5575 Rel8.Expr.Bool
76+ Rel8.Expr.Default
5677 Rel8.Expr.Eq
5778 Rel8.Expr.Function
5879 Rel8.Expr.Null
5980 Rel8.Expr.Opaleye
6081 Rel8.Expr.Ord
6182 Rel8.Expr.Order
83+ Rel8.Expr.Sequence
6284 Rel8.Expr.Serialize
85+ Rel8.Expr.Window
6386
6487 Rel8.FCF
6588
66− Rel8.Kind.Labels
67− Rel8.Kind.Necessity
89+ Rel8.Kind.Algebra
90+ Rel8.Kind.Context
6891
92+ Rel8.Generic.Construction
93+ Rel8.Generic.Construction.ADT
94+ Rel8.Generic.Construction.Record
95+ Rel8.Generic.Map
6996 Rel8.Generic.Record
97+ Rel8.Generic.Rel8able
7098 Rel8.Generic.Table
99+ Rel8.Generic.Table.ADT
100+ Rel8.Generic.Table.Record
71101
72102 Rel8.Order
73103
@@ -76,28 +106,26 @@ library
76106 Rel8.Query.Distinct
77107 Rel8.Query.Each
78108 Rel8.Query.Either
109+ Rel8.Query.Evaluate
79110 Rel8.Query.Exists
80111 Rel8.Query.Filter
112+ Rel8.Query.Indexed
81113 Rel8.Query.Limit
82114 Rel8.Query.List
83115 Rel8.Query.Maybe
84116 Rel8.Query.Null
85117 Rel8.Query.Opaleye
86118 Rel8.Query.Order
119+ Rel8.Query.Rebind
87120 Rel8.Query.Set
88121 Rel8.Query.SQL
89122 Rel8.Query.These
90123 Rel8.Query.Values
124+ Rel8.Query.Window
91125
92− Rel8.Schema.Column
93− Rel8.Schema.Context
94− Rel8.Schema.Context.Label
95126 Rel8.Schema.Context.Nullify
96127 Rel8.Schema.Dict
97128 Rel8.Schema.Field
98− Rel8.Schema.Generic
99− Rel8.Schema.Generic.Test
100− Rel8.Schema.HKD
101129 Rel8.Schema.HTable
102130 Rel8.Schema.HTable.Either
103131 Rel8.Schema.HTable.Identity
@@ -109,49 +137,54 @@ library
109137 Rel8.Schema.HTable.Nullify
110138 Rel8.Schema.HTable.Product
111139 Rel8.Schema.HTable.These
112− Rel8.Schema.HTable.Type
113140 Rel8.Schema.HTable.Vectorize
114− Rel8.Schema.Insert
115141 Rel8.Schema.Kind
116142 Rel8.Schema.Name
117143 Rel8.Schema.Null
118144 Rel8.Schema.Result
119145 Rel8.Schema.Spec
120− Rel8.Schema.Spec.ConstrainDBType
121− Rel8.Schema.Spec.ConstrainType
122− Rel8.Schema.Structure
123146 Rel8.Schema.Table
124147
125148 Rel8.Statement.Delete
126149 Rel8.Statement.Insert
150+ Rel8.Statement.OnConflict
127151 Rel8.Statement.Returning
128152 Rel8.Statement.Select
153+ Rel8.Statement.Set
154+ Rel8.Statement.SQL
129155 Rel8.Statement.Update
156+ Rel8.Statement.Using
130157 Rel8.Statement.View
158+ Rel8.Statement.Where
131159
132160 Rel8.Table
161+ Rel8.Table.ADT
133162 Rel8.Table.Aggregate
134163 Rel8.Table.Alternative
135164 Rel8.Table.Bool
165+ Rel8.Table.Cols
136166 Rel8.Table.Either
137167 Rel8.Table.Eq
138− Rel8.Table.Insert
168+ Rel8.Table.HKD
139169 Rel8.Table.List
140170 Rel8.Table.Maybe
141171 Rel8.Table.Name
142172 Rel8.Table.NonEmpty
173+ Rel8.Table.Null
174+ Rel8.Table.Nullify
143175 Rel8.Table.Opaleye
144176 Rel8.Table.Ord
145177 Rel8.Table.Order
146− Rel8.Table.Recontextualize
178+ Rel8.Table.Projection
179+ Rel8.Table.Rel8able
147180 Rel8.Table.Serialize
148− Rel8.Table.Tag
149181 Rel8.Table.These
182+ Rel8.Table.Transpose
150183 Rel8.Table.Undefined
184+ Rel8.Table.Window
151185
152186 Rel8.Type
153187 Rel8.Type.Array
154− Rel8.Type.Array1D
155188 Rel8.Type.Composite
156189 Rel8.Type.Eq
157190 Rel8.Type.Enum
@@ -167,6 +200,9 @@ library
167200 Rel8.Type.Sum
168201 Rel8.Type.Tag
169202
203+ Rel8.Window
204+
205+
170206test-suite tests
171207 type: exitcode-stdio-1.0
172208 build-depends:
@@ -175,9 +211,9 @@ test-suite tests
175211 , case-insensitive
176212 , containers
177213 , hasql
178− , hedgehog ^>=1.0.2
179− , lifted-base ^>=0.2.3.12
180− , monad-control ^>=1.0.2.3
214+ , hasql-transaction
215+ , hedgehog ^>= 1.0 || ^>= 1.1
216+ , mmorph
181217 , rel8
182218 , scientific
183219 , tasty
@@ -185,8 +221,12 @@ test-suite tests
185221 , text
186222 , time
187223 , tmp-postgres ^>=1.34.1.0
224+ , transformers
188225 , uuid
189226
227+ other-modules:
228+ Rel8.Generic.Rel8able.Test
229+
190230 main-is: Main.hs
191231 hs-source-dirs: tests
192232 default-language: Haskell2010
shell.nix+1−1
@@ -1,6 +1,6 @@
11let
22 sources = import ./nix/sources.nix;
3− pkgs = import sources.nixpkgs {};
3+ pkgs = import sources.nixpkgs {overlays = [];};
44 hsPkgs = import ./default.nix;
55in
66 hsPkgs.shellFor {
src/Rel8.hs+371−41
@@ -14,8 +14,8 @@ module Rel8
1414 , ReadShow(..)
1515
1616 -- **** Generic
17− , Composite(..)
18− , Enum(..)
17+ , Composite(..), DBComposite(..), compose, decompose
18+ , Enum(..), DBEnum(..), Enumable
1919
2020 -- *** @TypeInformation@
2121 , TypeInformation(..)
@@ -28,34 +28,42 @@ module Rel8
2828 , DBNum
2929 , DBIntegral
3030 , DBFractional
31+ , DBFloating
3132
3233 -- * Tables and higher-kinded tables
3334 , Rel8able, KRel8able
34− , Column, Field, Necessity( Required, Optional )
35− , Default
35+ , Column
36+ , HADT
3637 , HEither
3738 , HMaybe
3839 , HList
3940 , HNonEmpty
41+ , HNull
4042 , HThese
4143 , Lift
4244
4345 , Table(..)
46+ , HTable
47+ , Transposes
4448 , AltTable((<|>:))
45− , EqTable, (==:), (/=:)
46− , OrdTable, ascTable, descTable
49+ , AlternativeTable( emptyTable )
50+ , EqTable(..), (==:), (/=:)
51+ , OrdTable(..), (<:), (<=:), (>:), (>=:), ascTable, descTable, greatest, least
4752 , lit
4853 , bool
4954 , case_
55+ , castTable
5056
5157 -- ** @MaybeTable@
5258 , MaybeTable
5359 , maybeTable, ($?), nothingTable, justTable
5460 , isNothingTable, isJustTable
61+ , fromMaybeTable
5562 , optional
5663 , catMaybeTable
57− , bindMaybeTable
5864 , traverseMaybeTable
65+ , aggregateMaybeTable
66+ , nameMaybeTable
5967
6068 -- ** @EitherTable@
6169 , EitherTable
@@ -63,8 +71,9 @@ module Rel8
6371 , isLeftTable, isRightTable
6472 , keepLeftTable
6573 , keepRightTable
66− , bindEitherTable
6774 , bitraverseEitherTable
75+ , aggregateEitherTable
76+ , nameEitherTable
6877
6978 -- ** @TheseTable@
7079 , TheseTable
@@ -72,22 +81,73 @@ module Rel8
7281 , isThisTable, isThatTable, isThoseTable
7382 , hasHereTable, hasThereTable
7483 , justHereTable, justThereTable
84+ , alignMaybeTable
7585 , alignBy
7686 , keepHereTable, loseHereTable
7787 , keepThereTable, loseThereTable
7888 , keepThisTable, loseThisTable
7989 , keepThatTable, loseThatTable
8090 , keepThoseTable, loseThoseTable
81− , bindTheseTable
8291 , bitraverseTheseTable
92+ , aggregateTheseTable
93+ , nameTheseTable
8394
8495 -- ** @ListTable@
8596 , ListTable
97+ , listTable, ($*)
98+ , nameListTable
8699 , many
100+ , manyExpr
101+ , catListTable
102+ , catList
87103
88104 -- ** @NonEmptyTable@
89105 , NonEmptyTable
106+ , nonEmptyTable, ($+)
107+ , nameNonEmptyTable
90108 , some
109+ , someExpr
110+ , catNonEmptyTable
111+ , catNonEmpty
112+
113+ -- ** @NullTable@
114+ , NullTable
115+ , nullableTable, nullTable, nullifyTable
116+ , isNullTable, isNonNullTable
117+ , catNullTable
118+ , nameNullTable
119+ , toNullTable, toMaybeTable
120+
121+ -- ** Algebraic data types / sum types
122+ -- $adts
123+
124+ -- *** Naming of ADTs
125+ -- $naming
126+ , NameADT, nameADT
127+ , ADT, ADTable
128+
129+ -- *** Deconstruction of ADTs
130+ -- $deconstruction
131+ , DeconstructADT, deconstructADT
132+
133+ -- *** Construction of ADTs
134+ -- $construction
135+ , BuildADT, buildADT
136+ , ConstructADT, constructADT
137+
138+ -- *** Other ADT operations
139+ , AggregateADT, aggregateADT
140+
141+ -- *** Miscellaneous notes
142+ -- $misc-notes
143+
144+ -- ** @HKD@
145+ , HKD, HKDable
146+ , BuildHKD, buildHKD
147+ , ConstructHKD, constructHKD
148+ , DeconstructHKD, deconstructHKD
149+ , NameHKD, nameHKD
150+ , AggregateHKD, aggregateHKD
91151
92152 -- ** Table schemas
93153 , TableSchema(..)
@@ -100,8 +160,12 @@ module Rel8
100160 , Sql
101161 , litExpr
102162 , unsafeCastExpr
163+ , unsafeLiteral
103164
104165 -- ** @null@
166+ , NotNull
167+ , Nullable
168+ , Homonullable
105169 , null
106170 , nullify
107171 , nullable
@@ -120,6 +184,7 @@ module Rel8
120184 , (==.), (/=.), (==?), (/=?)
121185 , in_
122186 , boolExpr, caseExpr
187+ , like, ilike
123188
124189 -- ** Ordering
125190 , DBOrd
@@ -137,6 +202,13 @@ module Rel8
137202 , Query
138203 , showQuery
139204
205+ -- ** Projection
206+ , Projection
207+ , Projectable( project )
208+ , Biprojectable( biproject )
209+ , Projecting
210+ , Field
211+
140212 -- ** Selecting rows
141213 , Selects
142214 , each
@@ -145,8 +217,8 @@ module Rel8
145217 -- ** Filtering
146218 , filter
147219 , where_
148− , whereExists
149− , whereNotExists
220+ , present
221+ , absent
150222 , distinct
151223 , distinctOn
152224 , distinctOnBy
@@ -176,15 +248,16 @@ module Rel8
176248
177249 -- ** Aggregation
178250 , Aggregate
251+ , Aggregates
179252 , aggregate
180253 , countRows
181− , array1DAggExpr
182− , listAgg, listAggWithOrder, listAggExpr
183− , nonEmptyAgg, nonEmptyAggWithOrder, nonEmptyAggExpr
184254 , groupBy
255+ , listAgg, listAggExpr
256+ , mode
257+ , nonEmptyAgg, nonEmptyAggExpr
185258 , DBMax, max
186259 , DBMin, min
187− , DBSum, sum, sumWhere
260+ , DBSum, sum, sumWhere, avg
188261 , DBString, stringAgg
189262 , count
190263 , countStar
@@ -201,48 +274,71 @@ module Rel8
201274 , nullsFirst
202275 , nullsLast
203276
277+ -- ** Window functions
278+ , Window
279+ , window
280+ , Partition
281+ , over
282+ , partitionBy
283+ , orderPartitionBy
284+ , cumulative
285+ , cumulative_
286+ , currentRow
287+ , rowNumber
288+ , rank
289+ , denseRank
290+ , percentRank
291+ , cumeDist
292+ , ntile
293+ , lag
294+ , lead
295+ , firstValue
296+ , lastValue
297+ , nthValue
298+ , indexed
299+
300+ -- ** Bindings
301+ , rebind
302+
204303 -- * IO
205304 , Serializable
305+ , ToExprs
306+ , Result
206307
207308 -- * Running statements
309+ -- $running
310+
208311 -- ** @SELECT@
209312 , select
210313
211314 -- ** @INSERT@
212315 , Insert(..)
213316 , OnConflict(..)
317+ , Upsert(..)
214318 , insert
215− , toInsert
216− , toInsertDefaults
319+ , unsafeDefault
320+ , showInsert
217321
218322 -- ** @DELETE@
219323 , Delete(..)
220324 , delete
325+ , showDelete
221326
222327 -- ** @UPDATE@
223− , update
224328 , Update(..)
329+ , update
330+ , showUpdate
225331
226332 -- ** @.. RETURNING@
227333 , Returning(..)
228334
229335 -- ** @CREATE VIEW@
230336 , createView
337+ , createOrReplaceView
231338
232− -- * TODO
233− -- TODO
234− -- These need organizing, but are reachable from Rel8's documentation so we
235− -- do need to export and document them.
236− , Array1D
237− , NotArray
238− , Nullable
239− , NotNull
240− , HTable
241− , Labelable
242− , ToExprs(..)
243− , FromExprs
244− , Result
245− , HKDT(..)
339+ -- ** Sequences
340+ , nextval
341+ , evaluate
246342 ) where
247343
248344-- base
@@ -250,67 +346,88 @@ import Prelude ()
250346
251347-- rel8
252348import Rel8.Aggregate
349+import Rel8.Column
350+import Rel8.Column.ADT
351+import Rel8.Column.Either
352+import Rel8.Column.Lift
353+import Rel8.Column.List
354+import Rel8.Column.Maybe
355+import Rel8.Column.NonEmpty
356+import Rel8.Column.Null
357+import Rel8.Column.These
253358import Rel8.Expr
254359import Rel8.Expr.Aggregate
255360import Rel8.Expr.Bool
361+import Rel8.Expr.Default
256362import Rel8.Expr.Eq
257363import Rel8.Expr.Function
258364import Rel8.Expr.Null
259−import Rel8.Expr.Opaleye (unsafeCastExpr)
365+import Rel8.Expr.Opaleye (unsafeCastExpr, unsafeLiteral)
260366import Rel8.Expr.Ord
261367import Rel8.Expr.Order
262368import Rel8.Expr.Serialize
263−import Rel8.Kind.Necessity
369+import Rel8.Expr.Sequence
370+import Rel8.Expr.Text ( like, ilike )
371+import Rel8.Expr.Window hiding ( cumulative )
372+import Rel8.Generic.Rel8able ( KRel8able, Rel8able )
264373import Rel8.Order
265374import Rel8.Query
266375import Rel8.Query.Aggregate
267376import Rel8.Query.Distinct
268377import Rel8.Query.Each
269378import Rel8.Query.Either
379+import Rel8.Query.Evaluate
270380import Rel8.Query.Exists
271381import Rel8.Query.Filter
382+import Rel8.Query.Indexed
272383import Rel8.Query.Limit
273384import Rel8.Query.List
274385import Rel8.Query.Maybe
275386import Rel8.Query.Null
276387import Rel8.Query.Order
388+import Rel8.Query.Rebind
277389import Rel8.Query.SQL (showQuery)
278390import Rel8.Query.Set
279391import Rel8.Query.These
280392import Rel8.Query.Values
281−import Rel8.Schema.Column
282−import Rel8.Schema.Context.Label
393+import Rel8.Query.Window
283394import Rel8.Schema.Field
284−import Rel8.Schema.Generic
285−import Rel8.Schema.HKD
286395import Rel8.Schema.HTable
287396import Rel8.Schema.Name
288397import Rel8.Schema.Null hiding ( nullable )
289−import Rel8.Schema.Result
398+import Rel8.Schema.Result ( Result )
290399import Rel8.Schema.Table
291400import Rel8.Statement.Delete
292401import Rel8.Statement.Insert
402+import Rel8.Statement.OnConflict
293403import Rel8.Statement.Returning
294404import Rel8.Statement.Select
405+import Rel8.Statement.SQL
295406import Rel8.Statement.Update
296407import Rel8.Statement.View
297408import Rel8.Table
409+import Rel8.Table.ADT
298410import Rel8.Table.Aggregate
299411import Rel8.Table.Alternative
300412import Rel8.Table.Bool
301413import Rel8.Table.Either
302414import Rel8.Table.Eq
303−import Rel8.Table.Insert
415+import Rel8.Table.HKD
304416import Rel8.Table.List
305417import Rel8.Table.Maybe
306418import Rel8.Table.Name
307419import Rel8.Table.NonEmpty
420+import Rel8.Table.Null
421+import Rel8.Table.Opaleye ( castTable )
308422import Rel8.Table.Ord
309423import Rel8.Table.Order
424+import Rel8.Table.Projection
425+import Rel8.Table.Rel8able ()
310426import Rel8.Table.Serialize
311427import Rel8.Table.These
428+import Rel8.Table.Transpose
429+import Rel8.Table.Window
312430import Rel8.Type
313−import Rel8.Type.Array1D
314431import Rel8.Type.Composite
315432import Rel8.Type.Eq
316433import Rel8.Type.Enum
@@ -324,3 +441,216 @@ import Rel8.Type.ReadShow
324441import Rel8.Type.Semigroup
325442import Rel8.Type.String
326443import Rel8.Type.Sum
444+import Rel8.Window
445+
446+
447+-- $running
448+-- To run queries and otherwise interact with a PostgreSQL database, Rel8
449+-- provides 'select', 'insert', 'update' and 'delete' functions. Note that
450+-- 'insert', 'update' and 'delete' will generally need the
451+-- `DuplicateRecordFields` language extension enabled.
452+
453+-- $adts
454+-- Algebraic data types can be modelled between Haskell and SQL.
455+--
456+-- * Your SQL table needs a certain text field that tags which Haskell constructor is in use.
457+-- * You have to use a few combinators to specify the sum type's individual constructors.
458+-- * If you want to do case analysis at the @Expr@ (SQL) level, you can use 'maybe'/'either'-like eliminators.
459+--
460+-- The documentation in this section will assume a set of database types like this:
461+--
462+-- @
463+-- data Thing f = ThingEmployer (Employer f) | ThingPotato (Potato f) | Nullary
464+-- deriving stock Generic
465+--
466+-- data Employer f = Employer { employerId :: f Int32, employerName :: f Text}
467+-- deriving stock Generic
468+-- deriving anyclass Rel8able
469+--
470+-- data Potato f = Potato { size :: f Int32, grower :: f Text }
471+-- deriving stock Generic
472+-- deriving anyclass Rel8able
473+-- @
474+
475+-- $naming
476+--
477+-- First, in your 'TableSchema', name your type like this:
478+--
479+-- @
480+-- thingSchema :: TableSchema (ADT Thing Name)
481+-- thingSchema =
482+-- TableSchema
483+-- { schema = Nothing,
484+-- name = \"thing\",
485+-- columns =
486+-- nameADT @Thing
487+-- \"tag\"
488+-- Employer
489+-- { employerName = \"name\",
490+-- employerId = \"id\"
491+-- }
492+-- Potato {size = \"size\", grower = \"Mary\"}
493+-- }
494+-- @
495+--
496+-- Note that @nameADT \@Thing "tag"@ is variadic: it accepts one
497+-- argument per constructor, except the nullary ones (Nullary) because
498+-- there's nothing to do for them.
499+
500+-- $deconstruction
501+--
502+-- To deconstruct sum types at the SQL level, use 'deconstructADT',
503+-- which is also variadic, and has one argument for each
504+-- constructor. Similar to 'maybe'.
505+--
506+-- @
507+-- query :: Query (ADT Thing Expr)
508+-- query = do
509+-- thingExpr <- each thingSchema
510+-- where_ $
511+-- deconstructADT @Thing
512+-- (\employer -> employerName employer ==. lit \"Mary\")
513+-- (\potato -> grower potato ==. lit \"Mary\")
514+-- (lit False) -- Nullary case
515+-- thingExpr
516+-- pure thingExpr
517+-- @
518+--
519+-- SQL output:
520+--
521+-- @
522+-- SELECT
523+-- CAST("tag0_1" AS text) as "tag",
524+-- CAST("id1_1" AS int4) as "ThingEmployer/_1/employerId",
525+-- CAST("name2_1" AS text) as "ThingEmployer/_1/employerName",
526+-- CAST("size3_1" AS int4) as "ThingPotato/_1/size",
527+-- CAST("Mary4_1" AS text) as "ThingPotato/_1/grower"
528+-- FROM (SELECT
529+-- *
530+-- FROM (SELECT
531+-- "tag" as "tag0_1",
532+-- "id" as "id1_1",
533+-- "name" as "name2_1",
534+-- "size" as "size3_1",
535+-- "Mary" as "Mary4_1"
536+-- FROM "thing" as "T1") as "T1"
537+-- WHERE (CASE WHEN ("tag0_1") = (CAST(E'ThingPotato' AS text)) THEN ("Mary4_1") = (CAST(E'Mary' AS text))
538+-- WHEN ("tag0_1") = (CAST(E'Nullary' AS text)) THEN CAST(FALSE AS bool) ELSE ("name2_1") = (CAST(E'Mary' AS text)) END)) as "T1"
539+-- @
540+
541+-- $construction
542+--
543+-- To construct an ADT, you can use 'buildADT' or 'constructADT'. Consider the following type:
544+--
545+-- @
546+-- data Task f = Pending | Complete (CompletedTask f)
547+-- @
548+--
549+-- 'buildADT' is for constructing values of 'Task' in the 'Expr'
550+-- context. 'buildADT' needs two type-level arguments before its type
551+-- makes any sense. The first argument is the type of the "ADT", which
552+-- in our case is 'Task'. The second is the name of the constructor we
553+-- want to use. So that means we have the following possible
554+-- instantiations of 'buildADT' for 'Task':
555+--
556+-- @
557+-- > :t buildADT @Task @\"Pending\"
558+-- buildADT @Task @\"Pending\" :: ADT Task Expr
559+-- > :t buildADT @Task @\"Complete\"
560+-- buildADT @Task @\"Complete\" :: CompletedTask Expr -> ADT Task Expr
561+-- @
562+--
563+-- Note that as the "Pending" constructor has no fields, @buildADT
564+-- \@Task \@"Pending"@ is equivalent to @lit Pending@. But @buildADT
565+-- \@Task \@"Complete"@ is not the same as @lit . Complete@:
566+--
567+-- @
568+-- > :t lit . Complete
569+-- lit . Complete :: CompletedTask Result -> ADT Task Expr
570+-- @
571+--
572+--
573+-- Note that the former takes a @CompletedTask Expr@ while the latter
574+-- takes a @CompletedTask Result@. The former is more powerful because
575+-- you can construct @Task@s using dynamic values coming a database
576+-- query.
577+--
578+-- To show what this can look like in SQL, consider:
579+--
580+-- @
581+-- > :{
582+-- showQuery $ values
583+-- [ buildADT @Task @\"Pending\"
584+-- , buildADT @Task @\"Complete\" CompletedTask {date = Rel8.Expr.Time.now}
585+-- ]
586+-- :}
587+-- @
588+--
589+-- This produces the following SQL:
590+--
591+-- @
592+-- SELECT
593+-- CAST(\"values0_1\" AS text) as \"tag\",
594+-- CAST(\"values1_1\" AS timestamptz) as \"Complete/_1/date\"
595+-- FROM (SELECT
596+-- *
597+-- FROM (SELECT \"column1\" as \"values0_1\",
598+-- \"column2\" as \"values1_1\"
599+-- FROM
600+-- (VALUES
601+-- (CAST(E'Pending' AS text),CAST(NULL AS timestamptz)),
602+-- (CAST(E'Complete' AS text),CAST(now() AS timestamptz))) as \"V\") as \"T1\") as \"T1\"
603+-- @
604+--
605+-- This is what you get if you run it in @psql@:
606+--
607+--
608+-- @
609+-- tag | Complete/_1/date
610+-- ----------+-------------------------------
611+-- Pending |
612+-- Complete | 2022-05-19 21:28:23.969065+00
613+-- (2 rows)
614+-- @
615+--
616+-- "constructADT" is less convenient but more general alternative to
617+-- "buildADT". It requires only one type-level argument for its type
618+-- to make sense:
619+--
620+-- @
621+-- > :t constructADT @Task
622+-- constructADT @Task
623+-- :: (forall r. r -> (CompletedTask Expr -> r) -> r) -> ADT Task Expr
624+-- @
625+--
626+-- This might still seem a bit opaque, but basically it gives you a
627+-- Church-encoded constructor for arbitrary algebraic data types. You
628+-- might use it as follows:
629+--
630+-- @
631+-- let
632+-- pending :: ADT Task Expr
633+-- pending = constructADT @Task $ \pending _complete -> pending
634+--
635+-- complete :: ADT Task Expr
636+-- complete = constructADT @Task $ \_pending complete -> complete CompletedTask {date = Rel8.Expr.Time.now}
637+-- @
638+--
639+-- These values are otherwise identical to the ones we saw above with
640+-- @buildADT@, it's just a different style of constructing them.
641+--
642+
643+-- $misc-notes
644+--
645+-- 1. Note that the order of the arguments for all of these functions
646+-- is determined by the order of the constructors in the data
647+-- definition. If it were @data Task = Complete (CompletedTask f) |
648+-- Pending@ then the order of all the invocations of @constructADT@
649+-- and @deconstructADT@ would need to change.
650+--
651+-- 2. Maybe this is obvious, but just to spell it out: once you're in
652+-- the @Result@ context, you can of course construct @Task@ values
653+-- normally and use standard Haskell pattern-matching. @constructADT@
654+-- and @deconstructADT@ are specifically only needed in the @Expr@
655+-- context, and they allow you to do the equivalent of pattern
656+-- matching in PostgreSQL.
src/Rel8/Aggregate.hs+45−124
@@ -1,162 +1,83 @@
11{-# language DataKinds #-}
2−{-# language DerivingVia #-}
32{-# language FlexibleContexts #-}
43{-# language FlexibleInstances #-}
5−{-# language GADTs #-}
64{-# language MultiParamTypeClasses #-}
7−{-# language NamedFieldPuns #-}
8−{-# language PolyKinds #-}
5+{-# language RankNTypes #-}
96{-# language StandaloneKindSignatures #-}
107{-# language TypeFamilies #-}
118{-# language UndecidableInstances #-}
12−{-# language UndecidableSuperClasses #-}
139
1410module Rel8.Aggregate
15− ( Aggregate(..), foldInputs, mapInputs
16− , Aggregator(..), unsafeMakeAggregate
11+ ( Aggregate(..), zipOutputs
12+ , unsafeMakeAggregate
1713 , Aggregates
18− , Col( Aggregation )
1914 )
2015where
2116
2217-- base
23−import Data.Functor.Const ( Const( Const ), getConst )
24−import Data.Functor.Identity ( Identity )
18+import Control.Applicative ( liftA2 )
19+import Data.Functor.Identity ( Identity( Identity ) )
2520import Data.Kind ( Constraint, Type )
2621import Prelude
2722
23+-- profunctors
24+import Data.Profunctor ( dimap )
25+
2826-- opaleye
29−import qualified Opaleye.Internal.Aggregate as Opaleye
27+import qualified Opaleye.Aggregate as Opaleye
3028import qualified Opaleye.Internal.HaskellDB.PrimQuery as Opaleye
31−import qualified Opaleye.Internal.PackMap as Opaleye
29+import qualified Opaleye.Internal.Column as Opaleye
3230
3331-- rel8
34−import Rel8.Expr ( Expr, Col(..) )
35−import Rel8.Schema.Context ( Interpretation(..) )
36−import Rel8.Schema.Context.Label ( Labelable(..) )
37−import Rel8.Schema.HTable ( hfield, htabulate, htabulateA, hspecs )
38−import Rel8.Schema.Name ( Name )
32+import Rel8.Expr ( Expr )
33+import Rel8.Schema.HTable.Identity ( HIdentity(..) )
34+import qualified Rel8.Schema.Kind as K
3935import Rel8.Schema.Null ( Sql )
40−import Rel8.Schema.Result ( Result )
41−import Rel8.Schema.Spec ( Spec( Spec ), SSpec(..) )
42−import Rel8.Table ( Table, Columns, Context, fromColumns, toColumns )
43−import Rel8.Table.Recontextualize ( Recontextualize )
36+import Rel8.Table
37+ ( Table, Columns, Context, fromColumns, toColumns
38+ , FromExprs, fromResult, toResult
39+ , Transpose
40+ )
41+import Rel8.Table.Transpose ( Transposes )
4442import Rel8.Type ( DBType )
4543
46−-- semigroupoids
47−import Data.Functor.Apply ( Apply, (<.>) )
48−
49−
50−-- | An @Aggregate a@ describes how to aggregate @Table@s of type @a@. You can
51−-- unpack an @Aggregate@ back to @a@ by running it with 'Rel8.aggregate'. As
52−-- @Aggregate@ is almost an 'Applicative' functor - but there is no 'pure'
53−-- operation. This means 'Aggregate' is an instance of 'Apply', and you can
54−-- combine @Aggregate@s using the @<.>@ combinator.
55−type Aggregate :: k -> Type
56−data Aggregate a where
57− Aggregate :: !(Opaleye.Aggregator () a) -> Aggregate a
58−
59−
60−instance Functor Aggregate where
61− fmap f (Aggregate a) = Aggregate (fmap f a)
62−
63−
64−instance Apply Aggregate where
65− Aggregate f <.> Aggregate a = Aggregate (f <*> a)
6644
45+-- | 'Aggregate' is a special context used by 'Rel8.aggregate'.
46+type Aggregate :: K.Context
47+newtype Aggregate a = Aggregate (Opaleye.Aggregator () (Expr a))
6748
68−instance Interpretation Aggregate where
69− data Col Aggregate _spec where
70− Aggregation :: ()
71− => Aggregate (Expr a)
72− -> Col Aggregate ('Spec labels necessity a)
7349
74−
75−instance Table Expr a => Table Aggregate (Aggregate a) where
76− type Columns (Aggregate a) = Columns a
50+instance Sql DBType a => Table Aggregate (Aggregate a) where
51+ type Columns (Aggregate a) = HIdentity a
7752 type Context (Aggregate a) = Aggregate
53+ type FromExprs (Aggregate a) = a
54+ type Transpose to (Aggregate a) = to a
7855
79− toColumns a = htabulate $ \field -> case hfield hspecs field of
80− SSpec {} -> Aggregation $ unDB . (`hfield` field) . toColumns <$> a
81− fromColumns as = fmap fromColumns $ htabulateA $ \field ->
82− case hfield as field of
83− Aggregation a -> DB <$> a
84−
85−
86−instance Sql DBType a =>
87− Recontextualize Aggregate Aggregate (Aggregate (Expr a)) (Aggregate (Expr a))
88−
89−
90−instance Sql DBType a =>
91− Recontextualize Aggregate Expr (Aggregate (Expr a)) (Expr a)
92−
93−
94−instance Sql DBType a =>
95− Recontextualize Aggregate Result (Aggregate (Expr a)) (Identity a)
56+ toColumns = HIdentity
57+ fromColumns (HIdentity a) = a
58+ toResult = HIdentity . Identity
59+ fromResult (HIdentity (Identity a)) = a
9660
9761
98−instance Sql DBType a =>
99− Recontextualize Aggregate Name (Aggregate (Expr a)) (Name a)
100−
101−
102−instance Sql DBType a =>
103− Recontextualize Expr Aggregate (Expr a) (Aggregate (Expr a))
104−
105−
106−instance Sql DBType a =>
107− Recontextualize Result Aggregate (Identity a) (Aggregate (Expr a))
108−
109−
110−instance Sql DBType a =>
111− Recontextualize Name Aggregate (Name a) (Aggregate (Expr a))
112−
113−
114−instance Labelable Aggregate where
115− labeler (Aggregation aggregate) = Aggregation aggregate
116− unlabeler (Aggregation aggregate) = Aggregation aggregate
117−
118−
119−-- | @Aggregates a b@ means that the columns in @a@ are all 'Aggregate' 'Expr's
120−-- for the columns in @b@.
62+-- | @Aggregates a b@ means that the columns in @a@ are all 'Aggregate's
63+-- for the 'Expr' columns in @b@.
12164type Aggregates :: Type -> Type -> Constraint
122−class Recontextualize Aggregate Expr aggregates exprs => Aggregates aggregates exprs
123−instance Recontextualize Aggregate Expr aggregates exprs => Aggregates aggregates exprs
124−
125−
126−foldInputs :: Monoid b
127− => (Maybe Aggregator -> Opaleye.PrimExpr -> b) -> Aggregate a -> b
128−foldInputs f (Aggregate (Opaleye.Aggregator (Opaleye.PackMap agg))) =
129− getConst $ flip agg () $ \(aggregator, a) ->
130− Const $ f (detuplize <$> aggregator) a
131− where
132− detuplize (operation, ordering, distinction) =
133− Aggregator {operation, ordering, distinction}
134−
135−
136−mapInputs :: ()
137− => (Opaleye.PrimExpr -> Opaleye.PrimExpr) -> Aggregate a -> Aggregate a
138−mapInputs transform (Aggregate (Opaleye.Aggregator (Opaleye.PackMap agg))) =
139− Aggregate $ Opaleye.Aggregator $ Opaleye.PackMap $ agg . \f input ->
140− f (fmap transform input)
65+class Transposes Aggregate Expr aggregates exprs => Aggregates aggregates exprs
66+instance Transposes Aggregate Expr aggregates exprs => Aggregates aggregates exprs
14167
14268
143−type Aggregator :: Type
144−data Aggregator = Aggregator
145− { operation :: Opaleye.AggrOp
146− , ordering :: [Opaleye.OrderExpr]
147− , distinction :: Opaleye.AggrDistinct
148− }
69+zipOutputs :: ()
70+ => (Expr a -> Expr b -> Expr c) -> Aggregate a -> Aggregate b -> Aggregate c
71+zipOutputs f (Aggregate a) (Aggregate b) = Aggregate (liftA2 f a b)
14972
15073
151−unsafeMakeAggregate :: ()
152− => (input -> Opaleye.PrimExpr)
153− -> (Opaleye.PrimExpr -> output)
154− -> Maybe Aggregator
155− -> input
74+unsafeMakeAggregate :: forall (input :: Type) (output :: Type) n n' a a'. ()
75+ => (Expr input -> Opaleye.PrimExpr)
76+ -> (Opaleye.PrimExpr -> Expr output)
77+ -> Opaleye.Aggregator (Opaleye.Field_ n a) (Opaleye.Field_ n' a')
78+ -> Expr input
15679 -> Aggregate output
15780unsafeMakeAggregate input output aggregator expr =
158− Aggregate $ Opaleye.Aggregator $ Opaleye.PackMap $ \f _ ->
159− output <$> f (tuplize <$> aggregator, input expr)
160− where
161− tuplize Aggregator {operation, ordering, distinction} =
162− (operation, ordering, distinction)
81+ Aggregate $ dimap in_ out aggregator
82+ where out = output . Opaleye.unColumn
83+ in_ = Opaleye.Column . input . const expr
src/Rel8/Aggregate/Legacy.hsdeleted−92
@@ -1,92 +0,0 @@
1−{-# language FlexibleContexts #-}
2−{-# language ScopedTypeVariables #-}
3−{-# language TypeApplications #-}
4−{-# language TypeFamilies #-}
5−{-# language ViewPatterns #-}
6−
7−module Rel8.Aggregate.Legacy
8− ( Aggregates
9− , aggregate
10− , aggregateTabulation
11− , groupBy
12− , listAgg
13− , nonEmptyAgg
14− )
15−where
16−
17−-- base
18−import Data.Functor.Identity ( Identity( Identity ) )
19−import Prelude
20−
21−-- opaleye
22−import qualified Opaleye.Aggregate as Opaleye
23−
24−-- rel8
25−import Rel8.Aggregate ( Aggregates, Col(..) )
26−import Rel8.Expr ( Col(..) )
27−import Rel8.Expr.Aggregate ( groupByExpr, listAggExpr, nonEmptyAggExpr )
28−import Rel8.Query ( Query )
29−import Rel8.Query.Opaleye ( mapOpaleye )
30−import Rel8.Schema.Dict ( Dict( Dict ) )
31−import Rel8.Schema.HTable ( htabulate, hfield )
32−import Rel8.Schema.HTable.Vectorize ( hvectorize )
33−import Rel8.Table ( toColumns, fromColumns )
34−import Rel8.Table.Eq ( EqTable, eqTable )
35−import Rel8.Table.List ( ListTable )
36−import Rel8.Table.NonEmpty ( NonEmptyTable )
37−import Rel8.Table.Opaleye ( aggregator )
38−import Rel8.Tabulate ( Tabulation )
39−import qualified Rel8.Tabulate
40−
41−
42−-- | Apply an aggregation to all rows returned by a 'Query'.
43−aggregate :: Aggregates aggregates exprs => Query aggregates -> Query exprs
44−aggregate = mapOpaleye (Opaleye.aggregate aggregator) . fmap (fromColumns . toColumns)
45−
46−
47−aggregateTabulation
48− :: (EqTable k, Aggregates aggregates exprs)
49− => (t -> aggregates) -> Tabulation k t -> Tabulation k exprs
50−aggregateTabulation f =
51− Rel8.Tabulate.aggregateTabulation . fmap (fromColumns . toColumns . f)
52−
53−
54−-- | Group equal tables together. This works by aggregating each column in the
55−-- given table with 'groupByExpr'.
56−groupBy :: forall exprs aggregates. (EqTable exprs, Aggregates aggregates exprs)
57− => exprs -> aggregates
58−groupBy (toColumns -> exprs) = fromColumns $ htabulate $ \field ->
59− case hfield (eqTable @exprs) field of
60− Dict -> case hfield exprs field of
61− DB expr -> Aggregation $ groupByExpr expr
62−
63−
64−-- | Aggregate rows into a single row containing an array of all aggregated
65−-- rows. This can be used to associate multiple rows with a single row, without
66−-- changing the over cardinality of the query. This allows you to essentially
67−-- return a tree-like structure from queries.
68−--
69−-- For example, if we have a table of orders and each orders contains multiple
70−-- items, we could aggregate the table of orders, pairing each order with its
71−-- items:
72−--
73−-- @
74−-- ordersWithItems :: Query (Order Expr, ListTable (Item Expr))
75−-- ordersWithItems = do
76−-- order <- each orderSchema
77−-- items <- aggregate $ listAgg <$> itemsFromOrder order
78−-- return (order, items)
79−-- @
80−listAgg :: Aggregates aggregates exprs => exprs -> ListTable aggregates
81−listAgg (toColumns -> exprs) = fromColumns $
82− hvectorize
83− (\_ (Identity (DB a)) -> Aggregation $ listAggExpr a)
84− (pure exprs)
85−
86−
87−-- | Like 'listAgg', but the result is guaranteed to be a non-empty list.
88−nonEmptyAgg :: Aggregates aggregates exprs => exprs -> NonEmptyTable aggregates
89−nonEmptyAgg (toColumns -> exprs) = fromColumns $
90− hvectorize
91− (\_ (Identity (DB a)) -> Aggregation $ nonEmptyAggExpr a)
92− (pure exprs)
src/Rel8/Column.hsnew file+31
@@ -0,0 +1,31 @@
1+{-# language DataKinds #-}
2+{-# language StandaloneKindSignatures #-}
3+{-# language TypeFamilies #-}
4+
5+module Rel8.Column
6+ ( Column
7+ , TColumn
8+ )
9+where
10+
11+-- base
12+import Data.Kind ( Type )
13+import Prelude ()
14+
15+-- rel8
16+import Rel8.FCF ( Eval, Exp )
17+import qualified Rel8.Schema.Kind as K
18+import Rel8.Schema.Result ( Result )
19+
20+
21+-- | This type family is used to specify columns in 'Rel8able's. In @Column f
22+-- a@, @f@ is the context of the column (which should be left polymorphic in
23+-- 'Rel8able' definitions), and @a@ is the type of the column.
24+type Column :: K.Context -> Type -> Type
25+type family Column context a where
26+ Column Result a = a
27+ Column context a = context a
28+
29+
30+data TColumn :: K.Context -> Type -> Exp Type
31+type instance Eval (TColumn f a) = Column f a
src/Rel8/Column/ADT.hsnew file+23
@@ -0,0 +1,23 @@
1+{-# language DataKinds #-}
2+{-# language StandaloneKindSignatures #-}
3+{-# language TypeFamilies #-}
4+
5+module Rel8.Column.ADT
6+ ( HADT
7+ )
8+where
9+
10+-- base
11+import Data.Kind ( Type )
12+import Prelude ()
13+
14+-- rel8
15+import qualified Rel8.Schema.Kind as K
16+import Rel8.Schema.Result ( Result )
17+import Rel8.Table.ADT ( ADT )
18+
19+
20+type HADT :: K.Context -> K.Rel8able -> Type
21+type family HADT context t where
22+ HADT Result t = t Result
23+ HADT context t = ADT t context
src/Rel8/Column/Either.hsnew file+26
@@ -0,0 +1,26 @@
1+{-# language DataKinds #-}
2+{-# language StandaloneKindSignatures #-}
3+{-# language TypeFamilyDependencies #-}
4+
5+module Rel8.Column.Either
6+ ( HEither
7+ )
8+where
9+
10+-- base
11+import Data.Kind ( Type )
12+import Prelude
13+
14+-- rel8
15+import qualified Rel8.Schema.Kind as K
16+import Rel8.Schema.Result ( Result )
17+import Rel8.Table.Either ( EitherTable )
18+
19+
20+-- | Nest an 'Either' value within a 'Rel8able'. @HEither f a b@ will produce a
21+-- 'EitherTable' @a b@ in the 'Expr' context, and a 'Either' @a b@ in the
22+-- 'Result' context.
23+type HEither :: K.Context -> Type -> Type -> Type
24+type family HEither context = either | either -> context where
25+ HEither Result = Either
26+ HEither context = EitherTable context
src/Rel8/Column/Lift.hsnew file+23
@@ -0,0 +1,23 @@
1+{-# language DataKinds #-}
2+{-# language StandaloneKindSignatures #-}
3+{-# language TypeFamilies #-}
4+
5+module Rel8.Column.Lift
6+ ( Lift
7+ )
8+where
9+
10+-- base
11+import Data.Kind ( Type )
12+import Prelude ()
13+
14+-- rel8
15+import qualified Rel8.Schema.Kind as K
16+import Rel8.Schema.Result ( Result )
17+import Rel8.Table.HKD ( HKD )
18+
19+
20+type Lift :: K.Context -> Type -> Type
21+type family Lift context a where
22+ Lift Result a = a
23+ Lift context a = HKD a context
src/Rel8/Column/List.hsnew file+25
@@ -0,0 +1,25 @@
1+{-# language DataKinds #-}
2+{-# language StandaloneKindSignatures #-}
3+{-# language TypeFamilyDependencies #-}
4+
5+module Rel8.Column.List
6+ ( HList
7+ )
8+where
9+
10+-- base
11+import Data.Kind ( Type )
12+import Prelude ()
13+
14+-- rel8
15+import qualified Rel8.Schema.Kind as K
16+import Rel8.Schema.Result ( Result )
17+import Rel8.Table.List ( ListTable )
18+
19+
20+-- | Nest a list within a 'Rel8able'. @HList f a@ will produce a 'ListTable'
21+-- @a@ in the 'Expr' context, and a @[a]@ in the 'Result' context.
22+type HList :: K.Context -> Type -> Type
23+type family HList context = list | list -> context where
24+ HList Result = []
25+ HList context = ListTable context
src/Rel8/Column/Maybe.hsnew file+26
@@ -0,0 +1,26 @@
1+{-# language DataKinds #-}
2+{-# language StandaloneKindSignatures #-}
3+{-# language TypeFamilyDependencies #-}
4+
5+module Rel8.Column.Maybe
6+ ( HMaybe
7+ )
8+where
9+
10+-- base
11+import Data.Kind ( Type )
12+import Prelude
13+
14+-- rel8
15+import qualified Rel8.Schema.Kind as K
16+import Rel8.Schema.Result ( Result )
17+import Rel8.Table.Maybe ( MaybeTable )
18+
19+
20+-- | Nest a 'Maybe' value within a 'Rel8able'. @HMaybe f a@ will produce a
21+-- 'MaybeTable' @a@ in the 'Expr' context, and a 'Maybe' @a@ in the 'Result'
22+-- context.
23+type HMaybe :: K.Context -> Type -> Type
24+type family HMaybe context = maybe | maybe -> context where
25+ HMaybe Result = Maybe
26+ HMaybe context = MaybeTable context
src/Rel8/Column/NonEmpty.hsnew file+27
@@ -0,0 +1,27 @@
1+{-# language DataKinds #-}
2+{-# language StandaloneKindSignatures #-}
3+{-# language TypeFamilyDependencies #-}
4+
5+module Rel8.Column.NonEmpty
6+ ( HNonEmpty
7+ )
8+where
9+
10+-- base
11+import Data.Kind ( Type )
12+import Data.List.NonEmpty ( NonEmpty )
13+import Prelude ()
14+
15+-- rel8
16+import qualified Rel8.Schema.Kind as K
17+import Rel8.Schema.Result ( Result )
18+import Rel8.Table.NonEmpty ( NonEmptyTable )
19+
20+
21+-- | Nest a 'NonEmpty' list within a 'Rel8able'. @HNonEmpty f a@ will produce a
22+-- 'NonEmptyTable' @a@ in the 'Expr' context, and a 'NonEmpty' @a@ in the
23+-- 'Result' context.
24+type HNonEmpty :: K.Context -> Type -> Type
25+type family HNonEmpty context = nonEmpty | nonEmpty -> context where
26+ HNonEmpty Result = NonEmpty
27+ HNonEmpty context = NonEmptyTable context
src/Rel8/Column/Null.hsnew file+26
@@ -0,0 +1,26 @@
1+{-# language DataKinds #-}
2+{-# language StandaloneKindSignatures #-}
3+{-# language TypeFamilyDependencies #-}
4+
5+module Rel8.Column.Null
6+ ( HNull
7+ )
8+where
9+
10+-- base
11+import Data.Kind ( Type )
12+import Prelude
13+
14+-- rel8
15+import qualified Rel8.Schema.Kind as K
16+import Rel8.Schema.Result ( Result )
17+import Rel8.Table.Null ( NullTable )
18+
19+
20+-- | Nest a 'Null' value within a 'Rel8able'. @HNull f a@ will produce a
21+-- 'NullTable' @a@ in the 'Expr' context, and a @'Maybe' a@ in the 'Result'
22+-- context.
23+type HNull :: K.Context -> Type -> Type
24+type family HNull context = maybe | maybe -> context where
25+ HNull Result = Maybe
26+ HNull context = NullTable context
src/Rel8/Column/These.hsnew file+29
@@ -0,0 +1,29 @@
1+{-# language DataKinds #-}
2+{-# language StandaloneKindSignatures #-}
3+{-# language TypeFamilyDependencies #-}
4+
5+module Rel8.Column.These
6+ ( HThese
7+ )
8+where
9+
10+-- base
11+import Data.Kind ( Type )
12+import Prelude ()
13+
14+-- rel8
15+import qualified Rel8.Schema.Kind as K
16+import Rel8.Schema.Result ( Result )
17+import Rel8.Table.These ( TheseTable )
18+
19+-- these
20+import Data.These ( These )
21+
22+
23+-- | Nest an 'These' value within a 'Rel8able'. @HThese f a b@ will produce a
24+-- 'TheseTable' @a b@ in the 'Expr' context, and a 'These' @a b@ in the
25+-- 'Result' context.
26+type HThese :: K.Context -> Type -> Type -> Type
27+type family HThese context = these | these -> context where
28+ HThese Result = These
29+ HThese context = TheseTable context
src/Rel8/Expr.hs+40−43
@@ -1,27 +1,21 @@
11{-# language DataKinds #-}
22{-# language DerivingStrategies #-}
3+{-# language FlexibleContexts #-}
34{-# language FlexibleInstances #-}
4−{-# language GADTs #-}
55{-# language MultiParamTypeClasses #-}
6−{-# language PolyKinds #-}
7−{-# language RoleAnnotations #-}
86{-# language ScopedTypeVariables #-}
9−{-# language StandaloneDeriving #-}
107{-# language StandaloneKindSignatures #-}
118{-# language TypeApplications #-}
129{-# language TypeFamilies #-}
1310{-# language UndecidableInstances #-}
14−{-# language UndecidableSuperClasses #-}
1511
1612module Rel8.Expr
1713 ( Expr(..)
18− , Col( DB, unDB )
1914 )
2015where
2116
2217-- base
23−import Data.Functor.Identity ( Identity )
24−import Data.Kind ( Type )
18+import Data.Functor.Identity ( Identity( Identity ) )
2519import Data.String ( IsString, fromString )
2620import Prelude hiding ( null )
2721
@@ -29,6 +23,7 @@ import Prelude hiding ( null )
2923import qualified Opaleye.Internal.HaskellDB.PrimQuery as Opaleye
3024
3125-- rel8
26+import Rel8.Expr.Function ( function, nullaryFunction )
3227import Rel8.Expr.Null ( liftOpNull, nullify )
3328import Rel8.Expr.Opaleye
3429 ( castExpr
@@ -37,28 +32,24 @@ import Rel8.Expr.Opaleye
3732 , zipPrimExprsWith
3833 )
3934import Rel8.Expr.Serialize ( litExpr )
40−import Rel8.Schema.Context ( Interpretation, Col )
41−import Rel8.Schema.Context.Label ( Labelable, labeler, unlabeler )
42−import Rel8.Schema.HTable.Type ( HType( HType ) )
35+import Rel8.Schema.HTable.Identity ( HIdentity( HIdentity ) )
36+import qualified Rel8.Schema.Kind as K
4337import Rel8.Schema.Null ( Nullity( Null, NotNull ), Sql, nullable )
44−import Rel8.Schema.Result ( Result )
45−import Rel8.Schema.Spec ( Spec( Spec ) )
46−import Rel8.Table ( Table, Columns, Context, fromColumns, toColumns )
47−import Rel8.Table.Recontextualize ( Recontextualize )
38+import Rel8.Table
39+ ( Table, Columns, Context, fromColumns, toColumns
40+ , FromExprs, fromResult, toResult
41+ , Transpose
42+ )
4843import Rel8.Type ( DBType )
4944import Rel8.Type.Monoid ( DBMonoid, memptyExpr )
50−import Rel8.Type.Num ( DBFractional, DBNum )
45+import Rel8.Type.Num ( DBFloating, DBFractional, DBNum )
5146import Rel8.Type.Semigroup ( DBSemigroup, (<>.) )
5247
5348
5449-- | Typed SQL expressions.
55−type role Expr representational
56−type Expr :: k -> Type
57−data Expr a where
58− Expr :: k ~ Type => !Opaleye.PrimExpr -> Expr (a :: k)
59−
60−
61−deriving stock instance Show (Expr a)
50+type Expr :: K.Context
51+newtype Expr a = Expr Opaleye.PrimExpr
52+ deriving stock Show
6253
6354
6455instance Sql DBSemigroup a => Semigroup (Expr a) where
@@ -101,28 +92,34 @@ instance Sql DBFractional a => Fractional (Expr a) where
10192 castExpr . Expr . Opaleye.ConstExpr . Opaleye.NumericLit . realToFrac
10293
10394
104−instance Interpretation Expr where
105− data Col Expr _spec where
106− DB :: {unDB :: Expr a} -> Col Expr ('Spec labels necessity a)
95+instance Sql DBFloating a => Floating (Expr a) where
96+ pi = nullaryFunction "PI"
97+ exp = function "exp"
98+ log = function "ln"
99+ sqrt = function "sqrt"
100+ (**) = zipPrimExprsWith (Opaleye.BinExpr (Opaleye.:^))
101+ logBase = function "log"
102+ sin = function "sin"
103+ cos = function "cos"
104+ tan = function "tan"
105+ asin = function "asin"
106+ acos = function "acos"
107+ atan = function "atan"
108+ sinh = function "sinh"
109+ cosh = function "cosh"
110+ tanh = function "tanh"
111+ asinh = function "asinh"
112+ acosh = function "acosh"
113+ atanh = function "atanh"
107114
108115
109116instance Sql DBType a => Table Expr (Expr a) where
110− type Columns (Expr a) = HType a
117+ type Columns (Expr a) = HIdentity a
111118 type Context (Expr a) = Expr
119+ type FromExprs (Expr a) = a
120+ type Transpose to (Expr a) = to a
112121
113− toColumns a = HType (DB a)
114− fromColumns (HType (DB a)) = a
115−
116−
117−instance Sql DBType a => Recontextualize Expr Expr (Expr a) (Expr a)
118−
119−
120−instance Sql DBType a => Recontextualize Expr Result (Expr a) (Identity a)
121−
122−
123−instance Sql DBType a => Recontextualize Result Expr (Identity a) (Expr a)
124−
125−
126−instance Labelable Expr where
127− labeler (DB a) = DB a
128− unlabeler (DB a) = DB a
122+ toColumns a = HIdentity a
123+ fromColumns (HIdentity a) = a
124+ toResult a = HIdentity (Identity a)
125+ fromResult (HIdentity (Identity a)) = a
src/Rel8/Expr.hs-boot+6−8
@@ -1,6 +1,4 @@
1−{-# language GADTs #-}
2−{-# language PolyKinds #-}
3−{-# language RoleAnnotations #-}
1+{-# language DataKinds #-}
42{-# language StandaloneKindSignatures #-}
53
64module Rel8.Expr
@@ -9,14 +7,14 @@ module Rel8.Expr
97where
108
119-- base
12−import Data.Kind ( Type )
1310import Prelude ()
1411
1512-- opaleye
1613import qualified Opaleye.Internal.HaskellDB.PrimQuery as Opaleye
1714
15+-- rel8
16+import Rel8.Schema.Kind ( Context )
1817
19−type role Expr representational
20−type Expr :: k -> Type
21−data Expr a where
22− Expr :: k ~ Type => !Opaleye.PrimExpr -> Expr (a :: k)
18+
19+type Expr :: Context
20+newtype Expr a = Expr Opaleye.PrimExpr
src/Rel8/Expr/Aggregate.hs+53−115
@@ -10,10 +10,11 @@ module Rel8.Expr.Aggregate
1010 , and, or
1111 , min, max
1212 , sum, sumWhere
13+ , avg
1314 , stringAgg
1415 , groupByExpr
15− , array1DAggExpr, listAggExpr, nonEmptyAggExpr
16− , listAggExprWithOrder, nonEmptyAggExprWithOrder
16+ , listAggExpr, nonEmptyAggExpr
17+ , slistAggExpr, snonEmptyAggExpr
1718 )
1819where
1920
@@ -23,10 +24,12 @@ import Data.List.NonEmpty ( NonEmpty )
2324import Prelude hiding ( and, max, min, null, or, sum )
2425
2526-- opaleye
26−import qualified Opaleye.Internal.HaskellDB.PrimQuery as Opaleye
27+import qualified Opaleye.Internal.Aggregate as Opaleye
28+import Opaleye.Internal.Column ( Field_( Column ) )
29+import qualified Opaleye.Aggregate as Opaleye
2730
2831-- rel8
29−import Rel8.Aggregate ( Aggregate, Aggregator(..), unsafeMakeAggregate )
32+import Rel8.Aggregate ( Aggregate, unsafeMakeAggregate )
3033import Rel8.Expr ( Expr )
3134import Rel8.Expr.Bool ( caseExpr )
3235import Rel8.Expr.Opaleye
@@ -37,11 +40,11 @@ import Rel8.Expr.Opaleye
3740 )
3841import Rel8.Expr.Null ( null )
3942import Rel8.Expr.Serialize ( litExpr )
40−import Rel8.Order ( Order, toOrderExprs )
41−import Rel8.Schema.Null ( Sql )
42−import Rel8.Type.Array ( fromPrimArray )
43−import Rel8.Type.Array1D ( Array1D, NotArray )
43+import Rel8.Schema.Null ( Sql, Unnullify )
44+import Rel8.Type ( DBType, typeInformation )
45+import Rel8.Type.Array ( encodeArrayElement )
4446import Rel8.Type.Eq ( DBEq )
47+import Rel8.Type.Information ( TypeInformation )
4548import Rel8.Type.Num ( DBNum )
4649import Rel8.Type.Ord ( DBMax, DBMin )
4750import Rel8.Type.String ( DBString )
@@ -49,164 +52,99 @@ import Rel8.Type.Sum ( DBSum )
4952
5053
5154-- | Count the occurances of a single column. Corresponds to @COUNT(a)@
52−count :: Expr a -> Aggregate (Expr Int64)
53−count = unsafeMakeAggregate toPrimExpr fromPrimExpr $
54− Just Aggregator
55− { operation = Opaleye.AggrCount
56− , ordering = []
57− , distinction = Opaleye.AggrAll
58− }
59−
55+count :: Expr a -> Aggregate Int64
56+count = unsafeMakeAggregate toPrimExpr fromPrimExpr Opaleye.count
6057
6158-- | Count the number of distinct occurances of a single column. Corresponds to
6259-- @COUNT(DISTINCT a)@
63−countDistinct :: Sql DBEq a => Expr a -> Aggregate (Expr Int64)
60+countDistinct :: Sql DBEq a => Expr a -> Aggregate Int64
6461countDistinct = unsafeMakeAggregate toPrimExpr fromPrimExpr $
65− Just Aggregator
66− { operation = Opaleye.AggrCount
67− , ordering = []
68− , distinction = Opaleye.AggrDistinct
69− }
62+ Opaleye.distinctAggregator Opaleye.count
7063
7164
7265-- | Corresponds to @COUNT(*)@.
73−countStar :: Aggregate (Expr Int64)
66+countStar :: Aggregate Int64
7467countStar = count (litExpr True)
7568
7669
7770-- | A count of the number of times a given expression is @true@.
78−countWhere :: Expr Bool -> Aggregate (Expr Int64)
71+countWhere :: Expr Bool -> Aggregate Int64
7972countWhere condition = count (caseExpr [(condition, litExpr (Just True))] null)
8073
8174
8275-- | Corresponds to @bool_and@.
83−and :: Expr Bool -> Aggregate (Expr Bool)
84−and = unsafeMakeAggregate toPrimExpr fromPrimExpr $
85− Just Aggregator
86− { operation = Opaleye.AggrBoolAnd
87− , ordering = []
88− , distinction = Opaleye.AggrAll
89− }
76+and :: Expr Bool -> Aggregate Bool
77+and = unsafeMakeAggregate toPrimExpr fromPrimExpr Opaleye.boolAnd
9078
9179
9280-- | Corresponds to @bool_or@.
93−or :: Expr Bool -> Aggregate (Expr Bool)
94−or = unsafeMakeAggregate toPrimExpr fromPrimExpr $
95− Just Aggregator
96− { operation = Opaleye.AggrBoolOr
97− , ordering = []
98− , distinction = Opaleye.AggrAll
99− }
81+or :: Expr Bool -> Aggregate Bool
82+or = unsafeMakeAggregate toPrimExpr fromPrimExpr Opaleye.boolOr
10083
10184
10285-- | Produce an aggregation for @Expr a@ using the @max@ function.
103−max :: Sql DBMax a => Expr a -> Aggregate (Expr a)
104−max = unsafeMakeAggregate toPrimExpr fromPrimExpr $
105− Just Aggregator
106− { operation = Opaleye.AggrMax
107− , ordering = []
108− , distinction = Opaleye.AggrAll
109− }
86+max :: Sql DBMax a => Expr a -> Aggregate a
87+max = unsafeMakeAggregate toPrimExpr fromPrimExpr Opaleye.unsafeMax
11088
11189
11290-- | Produce an aggregation for @Expr a@ using the @max@ function.
113−min :: Sql DBMin a => Expr a -> Aggregate (Expr a)
114−min = unsafeMakeAggregate toPrimExpr fromPrimExpr $
115− Just Aggregator
116− { operation = Opaleye.AggrMin
117− , ordering = []
118− , distinction = Opaleye.AggrAll
119− }
91+min :: Sql DBMin a => Expr a -> Aggregate a
92+min = unsafeMakeAggregate toPrimExpr fromPrimExpr Opaleye.unsafeMin
12093
12194-- | Corresponds to @sum@. Note that in SQL, @sum@ is type changing - for
12295-- example the @sum@ of @integer@ returns a @bigint@. Rel8 doesn't support
123−-- this, and will add explicit cast back to the original input type. This can
96+-- this, and will add explicit casts back to the original input type. This can
12497-- lead to overflows, and if you anticipate very large sums, you should upcast
12598-- your input.
126−sum :: Sql DBSum a => Expr a -> Aggregate (Expr a)
127−sum = unsafeMakeAggregate toPrimExpr (castExpr . fromPrimExpr) $
128− Just Aggregator
129− { operation = Opaleye.AggrSum
130− , ordering = []
131− , distinction = Opaleye.AggrAll
132− }
99+sum :: Sql DBSum a => Expr a -> Aggregate a
100+sum = unsafeMakeAggregate toPrimExpr (castExpr . fromPrimExpr) Opaleye.unsafeSum
101+
133102
103+-- | Corresponds to @avg@. Note that in SQL, @avg@ is type changing - for
104+-- example, the @avg@ of @integer@ returns a @numeric@. Rel8 doesn't support
105+-- this, and will add explicit casts back to the original input type. If you
106+-- need a fractional result on an integral column, you should cast your input
107+-- to 'Double' or 'Data.Scientific.Scientific' before calling 'avg'.
108+avg :: Sql DBSum a => Expr a -> Aggregate a
109+avg = unsafeMakeAggregate toPrimExpr (castExpr . fromPrimExpr) Opaleye.unsafeAvg
134110
135111-- | Take the sum of all expressions that satisfy a predicate.
136112sumWhere :: (Sql DBNum a, Sql DBSum a)
137− => Expr Bool -> Expr a -> Aggregate (Expr a)
113+ => Expr Bool -> Expr a -> Aggregate a
138114sumWhere condition a = sum (caseExpr [(condition, a)] 0)
139115
140116
141117-- | Corresponds to @string_agg()@.
142118stringAgg :: Sql DBString a
143− => Expr db -> Expr a -> Aggregate (Expr a)
119+ => Expr db -> Expr a -> Aggregate a
144120stringAgg delimiter =
145− unsafeMakeAggregate toPrimExpr (castExpr . fromPrimExpr) $
146− Just Aggregator
147− { operation = Opaleye.AggrStringAggr (toPrimExpr delimiter)
148− , ordering = []
149− , distinction = Opaleye.AggrAll
150− }
121+ unsafeMakeAggregate toPrimExpr (castExpr . fromPrimExpr) (Opaleye.stringAgg (Column (toPrimExpr delimiter)))
151122
152123
153124-- | Aggregate a value by grouping by it.
154−groupByExpr :: Sql DBEq a => Expr a -> Aggregate (Expr a)
155−groupByExpr = unsafeMakeAggregate toPrimExpr fromPrimExpr Nothing
156−
157−
158−-- | Collect expressions values as an array.
159−array1DAggExpr :: NotArray a => Expr a -> Aggregate (Expr (Array1D a))
160−array1DAggExpr = unsafeMakeAggregate toPrimExpr fromPrimExpr $ Just
161− Aggregator
162− { operation = Opaleye.AggrArr
163− , ordering = []
164− , distinction = Opaleye.AggrAll
165− }
125+groupByExpr :: Sql DBEq a => Expr a -> Aggregate a
126+groupByExpr = unsafeMakeAggregate toPrimExpr fromPrimExpr Opaleye.groupBy
166127
167128
168129-- | Collect expressions values as a list.
169−listAggExpr :: Expr a -> Aggregate (Expr [a])
170−listAggExpr = unsafeMakeAggregate toPrimExpr from $ Just
171− Aggregator
172− { operation = Opaleye.AggrArr
173− , ordering = []
174− , distinction = Opaleye.AggrAll
175− }
176− where
177− from = fromPrimExpr . fromPrimArray
130+listAggExpr :: Sql DBType a => Expr a -> Aggregate [a]
131+listAggExpr = slistAggExpr typeInformation
178132
179133
180134-- | Collect expressions values as a non-empty list.
181−nonEmptyAggExpr :: Expr a -> Aggregate (Expr (NonEmpty a))
182−nonEmptyAggExpr = unsafeMakeAggregate toPrimExpr from $ Just
183− Aggregator
184− { operation = Opaleye.AggrArr
185− , ordering = []
186− , distinction = Opaleye.AggrAll
187− }
188− where
189− from = fromPrimExpr . fromPrimArray
135+nonEmptyAggExpr :: Sql DBType a => Expr a -> Aggregate (NonEmpty a)
136+nonEmptyAggExpr = snonEmptyAggExpr typeInformation
190137
191138
192−listAggExprWithOrder :: Order o -> o -> Expr a -> Aggregate (Expr [a])
193−listAggExprWithOrder order o = unsafeMakeAggregate toPrimExpr from $ Just
194− Aggregator
195− { operation = Opaleye.AggrArr
196− , ordering = toOrderExprs order o
197− , distinction = Opaleye.AggrAll
198− }
139+slistAggExpr :: ()
140+ => TypeInformation (Unnullify a) -> Expr a -> Aggregate [a]
141+slistAggExpr info = unsafeMakeAggregate to fromPrimExpr Opaleye.arrayAgg
199142 where
200− from = fromPrimExpr . fromPrimArray
143+ to = encodeArrayElement info . toPrimExpr
201144
202145
203−nonEmptyAggExprWithOrder :: ()
204− => Order o -> o -> Expr a -> Aggregate (Expr (NonEmpty a))
205−nonEmptyAggExprWithOrder order o = unsafeMakeAggregate toPrimExpr from $ Just
206− Aggregator
207− { operation = Opaleye.AggrArr
208− , ordering = toOrderExprs order o
209− , distinction = Opaleye.AggrAll
210− }
146+snonEmptyAggExpr :: ()
147+ => TypeInformation (Unnullify a) -> Expr a -> Aggregate (NonEmpty a)
148+snonEmptyAggExpr info = unsafeMakeAggregate to fromPrimExpr Opaleye.arrayAgg
211149 where
212− from = fromPrimExpr . fromPrimArray
150+ to = encodeArrayElement info . toPrimExpr
src/Rel8/Expr/Array.hs+6−6
@@ -25,21 +25,21 @@ import Rel8.Expr.Opaleye
2525 , zipPrimExprsWith
2626 )
2727import Rel8.Type ( DBType, typeInformation )
28−import Rel8.Type.Array ( array, zipPrimArraysWith )
28+import Rel8.Type.Array ( array )
2929import Rel8.Type.Information ( TypeInformation(..) )
30−import Rel8.Schema.Null ( Unnullify, Nullity, Sql )
30+import Rel8.Schema.Null ( Unnullify, Sql )
3131
3232
3333sappend :: Expr [a] -> Expr [a] -> Expr [a]
34−sappend = zipPrimExprsWith (zipPrimArraysWith (Opaleye.BinExpr (Opaleye.:||)))
34+sappend = zipPrimExprsWith (Opaleye.BinExpr (Opaleye.:||))
3535
3636
3737sappend1 :: Expr (NonEmpty a) -> Expr (NonEmpty a) -> Expr (NonEmpty a)
38−sappend1 = zipPrimExprsWith (zipPrimArraysWith (Opaleye.BinExpr (Opaleye.:||)))
38+sappend1 = zipPrimExprsWith (Opaleye.BinExpr (Opaleye.:||))
3939
4040
41−sempty :: Nullity a -> TypeInformation (Unnullify a) -> Expr [a]
42−sempty _ info = fromPrimExpr $ array info []
41+sempty :: TypeInformation (Unnullify a) -> Expr [a]
42+sempty info = fromPrimExpr $ array info []
4343
4444
4545slistOf :: TypeInformation (Unnullify a) -> [Expr a] -> Expr [a]
src/Rel8/Expr/Default.hsnew file+35
@@ -0,0 +1,35 @@
1+module Rel8.Expr.Default
2+ ( unsafeDefault
3+ )
4+where
5+
6+-- base
7+import Prelude ()
8+
9+-- opaleye
10+import qualified Opaleye.Internal.HaskellDB.PrimQuery as Opaleye
11+
12+-- rel8
13+import Rel8.Expr ( Expr )
14+import Rel8.Expr.Opaleye ( fromPrimExpr )
15+
16+
17+-- | Corresponds to the SQL @DEFAULT@ expression.
18+--
19+-- This 'Expr' is unsafe for numerous reasons, and should be used with care:
20+--
21+-- 1. This 'Expr' only makes sense in an @INSERT@ or @UPDATE@ statement.
22+--
23+-- 2. Rel8 is not able to verify that a particular column actually has a
24+-- @DEFAULT@ value. Trying to use @unsafeDefault@ where there is no default
25+-- will cause a runtime crash
26+--
27+-- 3. @DEFAULT@ values can not be transformed. For example, the innocuous Rel8
28+-- code @unsafeDefault + 1@ will crash, despite type checking.
29+--
30+-- Given all these caveats, we suggest avoiding the use of default values where
31+-- possible, instead being explicit. A common scenario where default values are
32+-- used is with auto-incrementing identifier columns. In this case, we suggest
33+-- using 'Rel8.nextval' instead.
34+unsafeDefault :: Expr a
35+unsafeDefault = fromPrimExpr Opaleye.DefaultInsertExpr
src/Rel8/Expr/Eq.hs+1−1
@@ -22,7 +22,7 @@ import Prelude
2222import qualified Opaleye.Internal.HaskellDB.PrimQuery as Opaleye
2323
2424-- rel8
25−import {-# SOURCE #-} Rel8.Expr ( Expr )
25+import Rel8.Expr ( Expr )
2626import Rel8.Expr.Bool ( (&&.), (||.), false, or_, coalesce )
2727import Rel8.Expr.Null ( isNull, unsafeLiftOpNull )
2828import Rel8.Expr.Opaleye ( fromPrimExpr, toPrimExpr, zipPrimExprsWith )
src/Rel8/Expr/Function.hs+1−1
@@ -20,7 +20,7 @@ import Prelude
2020import qualified Opaleye.Internal.HaskellDB.PrimQuery as Opaleye
2121
2222-- rel8
23−import Rel8.Expr ( Expr( Expr ) )
23+import {-# SOURCE #-} Rel8.Expr ( Expr( Expr ) )
2424import Rel8.Expr.Opaleye
2525 ( castExpr
2626 , fromPrimExpr, toPrimExpr, zipPrimExprsWith
src/Rel8/Expr/Null.hs+3−3
@@ -5,7 +5,7 @@
55{-# options -fno-warn-redundant-constraints #-}
66
77module Rel8.Expr.Null
8− ( null, snull, nullable, nullableOf
8+ ( null, snull, nullableExpr, nullableOf
99 , isNull, isNonNull
1010 , nullify, unsafeUnnullify
1111 , mapNull, liftOpNull
@@ -40,8 +40,8 @@ unsafeUnnullify (Expr a) = Expr a
4040
4141
4242-- | Like 'maybe', but to eliminate @null@.
43−nullable :: Expr b -> (Expr a -> Expr b) -> Expr (Maybe a) -> Expr b
44−nullable b f ma = boolExpr (f (unsafeUnnullify ma)) b (isNull ma)
43+nullableExpr :: Expr b -> (Expr a -> Expr b) -> Expr (Maybe a) -> Expr b
44+nullableExpr b f ma = boolExpr (f (unsafeUnnullify ma)) b (isNull ma)
4545
4646
4747nullableOf :: DBType a => Maybe (Expr a) -> Expr (Maybe a)
src/Rel8/Expr/Num.hs+43−10
@@ -4,18 +4,24 @@
44{-# options_ghc -fno-warn-redundant-constraints #-}
55
66module Rel8.Expr.Num
7− ( fromIntegral, realToFrac, div, mod, ceiling, floor, round, truncate
7+ ( fromIntegral
8+ , realToFrac
9+ , div, mod, divMod
10+ , quot, rem, quotRem
11+ , ceiling, floor, round, truncate
812 )
913where
1014
1115-- base
12−import Prelude ()
16+import Prelude ( (+), (-), fst, negate, signum, snd )
1317
1418-- rel
1519import Rel8.Expr ( Expr( Expr ) )
20+import Rel8.Expr.Eq ( (==.) )
1621import Rel8.Expr.Function ( function )
1722import Rel8.Expr.Opaleye ( castExpr )
1823import Rel8.Schema.Null ( Homonullable, Sql )
24+import Rel8.Table.Bool ( bool )
1925import Rel8.Type.Num ( DBFractional, DBIntegral, DBNum )
2026
2127
@@ -39,17 +45,44 @@ realToFrac (Expr a) = castExpr (Expr a)
3945-- Corresponds to the @ceiling()@ function.
4046ceiling :: (Sql DBFractional a, Sql DBIntegral b, Homonullable a b)
4147 => Expr a -> Expr b
42−ceiling = function "CEILING"
48+ceiling = function "ceiling"
4349
4450
45−-- | Perform integral division. Corresponds to the @div()@ function.
51+-- | Emulates the behaviour of the Haskell function 'Prelude.div' in
52+-- PostgreSQL.
4653div :: Sql DBIntegral a => Expr a -> Expr a -> Expr a
47−div = function "DIV"
54+div n d = fst (divMod n d)
4855
4956
50−-- | Corresponds to the @mod()@ function.
57+-- | Emulates the behaviour of the Haskell function 'Prelude.mod' in
58+-- PostgreSQL.
5159mod :: Sql DBIntegral a => Expr a -> Expr a -> Expr a
52−mod = function "MOD"
60+mod n d = snd (divMod n d)
61+
62+
63+-- | Simultaneous 'div' and 'mod'.
64+divMod :: Sql DBIntegral a => Expr a -> Expr a -> (Expr a, Expr a)
65+divMod n d = bool qr (q - 1, r + d) (signum r ==. negate (signum d))
66+ where
67+ qr@(q, r) = quotRem n d
68+
69+
70+-- | Perform integral division. Corresponds to the @div()@ function in
71+-- PostgreSQL, which behaves like Haskell's 'Prelude.quot' rather than
72+-- 'Prelude.div'.
73+quot :: Sql DBIntegral a => Expr a -> Expr a -> Expr a
74+quot = function "div"
75+
76+
77+-- | Corresponds to the @mod()@ function in PostgreSQL, which behaves like
78+-- Haskell's 'Prelude.rem' rather than 'Prelude.mod'.
79+rem :: Sql DBIntegral a => Expr a -> Expr a -> Expr a
80+rem = function "mod"
81+
82+
83+-- | Simultaneous 'quot' and 'rem'.
84+quotRem :: Sql DBIntegral a => Expr a -> Expr a -> (Expr a, Expr a)
85+quotRem n d = (quot n d, rem n d)
5386
5487
5588-- | Round a 'DFractional' to a 'DBIntegral' by rounding to the nearest smaller
@@ -58,7 +91,7 @@ mod = function "MOD"
5891-- Corresponds to the @floor()@ function.
5992floor :: (Sql DBFractional a, Sql DBIntegral b, Homonullable a b)
6093 => Expr a -> Expr b
61−floor = function "FLOOR"
94+floor = function "floor"
6295
6396
6497-- | Round a 'DBFractional' to a 'DBIntegral' by rounding to the nearest
@@ -67,11 +100,11 @@ floor = function "FLOOR"
67100-- Corresponds to the @round()@ function.
68101round :: (Sql DBFractional a, Sql DBIntegral b, Homonullable a b)
69102 => Expr a -> Expr b
70−round = function "ROUND"
103+round = function "round"
71104
72105
73106-- | Round a 'DBFractional' to a 'DBIntegral' by rounding to the nearest
74107-- integer towards zero.
75108truncate :: (Sql DBFractional a, Sql DBIntegral b, Homonullable a b)
76109 => Expr a -> Expr b
77−truncate = function "TRUNC"
110+truncate = function "trunc"
src/Rel8/Expr/Opaleye.hs+19−5
@@ -10,7 +10,7 @@ module Rel8.Expr.Opaleye
1010 , scastExpr, sunsafeCastExpr
1111 , unsafeLiteral
1212 , fromPrimExpr, toPrimExpr, mapPrimExpr, zipPrimExprsWith, traversePrimExpr
13− , toColumn, fromColumn
13+ , toColumn, fromColumn, traverseFieldP
1414 )
1515where
1616
@@ -27,6 +27,9 @@ import Rel8.Schema.Null ( Unnullify, Sql )
2727import Rel8.Type ( DBType, typeInformation )
2828import Rel8.Type.Information ( TypeInformation(..) )
2929
30+-- profunctors
31+import Data.Profunctor ( Profunctor, dimap )
32+
3033
3134castExpr :: Sql DBType a => Expr a -> Expr a
3235castExpr = scastExpr typeInformation
@@ -48,8 +51,13 @@ sunsafeCastExpr TypeInformation {typeName} =
4851 fromPrimExpr . Opaleye.CastExpr typeName . toPrimExpr
4952
5053
51−unsafeLiteral :: Sql DBType a => String -> Expr a
52−unsafeLiteral = castExpr . Expr . Opaleye.ConstExpr . Opaleye.OtherLit
54+-- | Unsafely construct an expression from literal SQL.
55+--
56+-- This is an escape hatch, and can be used if Rel8 can not adequately express
57+-- the query you need. If you find yourself using this function, please let us
58+-- know, as it may indicate that something is missing from Rel8!
59+unsafeLiteral :: String -> Expr a
60+unsafeLiteral = Expr . Opaleye.ConstExpr . Opaleye.OtherLit
5361
5462
5563fromPrimExpr :: Opaleye.PrimExpr -> Expr a
@@ -75,9 +83,15 @@ traversePrimExpr :: Functor f
7583traversePrimExpr f = fmap fromPrimExpr . f . toPrimExpr
7684
7785
78−toColumn :: Opaleye.PrimExpr -> Opaleye.Column b
86+traverseFieldP :: Profunctor p
87+ => p (Opaleye.Field_ n x) (Opaleye.Field_ m y)
88+ -> p (Expr a) (Expr b)
89+traverseFieldP = dimap (toColumn . toPrimExpr) (fromPrimExpr . fromColumn)
90+
91+
92+toColumn :: Opaleye.PrimExpr -> Opaleye.Field_ n b
7993toColumn = Opaleye.Column
8094
8195
82−fromColumn :: Opaleye.Column b -> Opaleye.PrimExpr
96+fromColumn :: Opaleye.Field_ n b -> Opaleye.PrimExpr
8397fromColumn (Opaleye.Column a) = a
src/Rel8/Expr/Ord.hs+10−11
@@ -22,10 +22,9 @@ import qualified Opaleye.Internal.HaskellDB.PrimQuery as Opaleye
2222-- rel8
2323import Rel8.Expr ( Expr( Expr ) )
2424import Rel8.Expr.Bool ( (&&.), (||.), coalesce )
25−import Rel8.Expr.Null ( isNull, isNonNull, nullable, unsafeLiftOpNull )
25+import Rel8.Expr.Null ( isNull, isNonNull, nullableExpr, unsafeLiftOpNull )
2626import Rel8.Expr.Opaleye ( toPrimExpr, zipPrimExprsWith )
27−import Rel8.Schema.Null ( Nullity( Null, NotNull ), Sql )
28−import qualified Rel8.Schema.Null as Schema ( nullable )
27+import Rel8.Schema.Null ( Nullity( Null, NotNull ), Sql, nullable )
2928import Rel8.Type.Ord ( DBOrd )
3029
3130
@@ -49,7 +48,7 @@ ge = zipPrimExprsWith (Opaleye.BinExpr (Opaleye.:>=))
4948-- as @null@ will sort below any other value. For a version of @<@ that exactly
5049-- matches SQL, see '(<?)'.
5150(<.) :: forall a. Sql DBOrd a => Expr a -> Expr a -> Expr Bool
52−(<.) = case Schema.nullable @a of
51+(<.) = case nullable @a of
5352 Null -> \ma mb -> isNull ma &&. isNonNull mb ||. ma <? mb
5453 NotNull -> lt
5554infix 4 <.
@@ -59,7 +58,7 @@ infix 4 <.
5958-- as @null@ will sort below any other value. For a version of @<=@ that exactly
6059-- matches SQL, see '(<=?)'.
6160(<=.) :: forall a. Sql DBOrd a => Expr a -> Expr a -> Expr Bool
62−(<=.) = case Schema.nullable @a of
61+(<=.) = case nullable @a of
6362 Null -> \ma mb -> isNull ma ||. ma <=? mb
6463 NotNull -> le
6564infix 4 <=.
@@ -69,7 +68,7 @@ infix 4 <=.
6968-- as @null@ will sort below any other value. For a version of @>@ that exactly
7069-- matches SQL, see '(>?)'.
7170(>.) :: forall a. Sql DBOrd a => Expr a -> Expr a -> Expr Bool
72−(>.) = case Schema.nullable @a of
71+(>.) = case nullable @a of
7372 Null -> \ma mb -> isNonNull ma &&. isNull mb ||. ma >? mb
7473 NotNull -> gt
7574infix 4 >.
@@ -79,7 +78,7 @@ infix 4 >.
7978-- as @null@ will sort below any other value. For a version of @>=@ that
8079-- exactly matches SQL, see '(>=?)'.
8180(>=.) :: forall a. Sql DBOrd a => Expr a -> Expr a -> Expr Bool
82−(>=.) = case Schema.nullable @a of
81+(>=.) = case nullable @a of
8382 Null -> \ma mb -> isNull mb ||. ma >=? mb
8483 NotNull -> ge
8584infix 4 >=.
@@ -118,8 +117,8 @@ infix 4 >=?
118117--
119118-- Corresponds to the SQL @least()@ function.
120119leastExpr :: forall a. Sql DBOrd a => Expr a -> Expr a -> Expr a
121−leastExpr ma mb = case Schema.nullable @a of
122− Null -> nullable ma (\a -> nullable mb (least_ a) mb) ma
120+leastExpr ma mb = case nullable @a of
121+ Null -> nullableExpr ma (\a -> nullableExpr mb (least_ a) mb) ma
123122 NotNull -> least_ ma mb
124123 where
125124 least_ a b = Expr (Opaleye.FunExpr "LEAST" [toPrimExpr a, toPrimExpr b])
@@ -130,8 +129,8 @@ leastExpr ma mb = case Schema.nullable @a of
130129--
131130-- Corresponds to the SQL @greatest()@ function.
132131greatestExpr :: forall a. Sql DBOrd a => Expr a -> Expr a -> Expr a
133−greatestExpr ma mb = case Schema.nullable @a of
134− Null -> nullable mb (\a -> nullable ma (greatest_ a) mb) ma
132+greatestExpr ma mb = case nullable @a of
133+ Null -> nullableExpr mb (\a -> nullableExpr ma (greatest_ a) mb) ma
135134 NotNull -> greatest_ ma mb
136135 where
137136 greatest_ a b =
src/Rel8/Expr/Sequence.hsnew file+22
@@ -0,0 +1,22 @@
1+module Rel8.Expr.Sequence
2+ ( nextval
3+ )
4+where
5+
6+-- base
7+import Data.Int ( Int64 )
8+import Prelude
9+
10+-- rel8
11+import Rel8.Expr ( Expr )
12+import Rel8.Expr.Function ( function )
13+import Rel8.Expr.Serialize ( litExpr )
14+import Rel8.Expr.Text ( quoteIdent )
15+
16+-- text
17+import Data.Text ( pack )
18+
19+
20+-- | See https://www.postgresql.org/docs/current/functions-sequence.html
21+nextval :: String -> Expr Int64
22+nextval = function "nextval" . quoteIdent . litExpr . pack
src/Rel8/Expr/Text.hs+24−4
@@ -17,6 +17,9 @@ module Rel8.Expr.Text
1717 , pgClientEncoding, quoteIdent, quoteLiteral, quoteNullable, regexpReplace
1818 , regexpSplitToArray, repeat, replace, reverse, right, rpad, rtrim
1919 , splitPart, strpos, substr, translate
20+
21+ -- * @LIKE@ and @ILIKE@
22+ , like, ilike
2023 )
2124where
2225
@@ -24,7 +27,7 @@ where
2427import Data.Bool ( Bool )
2528import Data.Int ( Int32 )
2629import Data.Maybe ( Maybe( Nothing, Just ) )
27−import Prelude ()
30+import Prelude ( flip )
2831
2932-- bytestring
3033import Data.ByteString ( ByteString )
@@ -32,7 +35,6 @@ import Data.ByteString ( ByteString )
3235-- rel8
3336import Rel8.Expr ( Expr )
3437import Rel8.Expr.Function ( binaryOperator, function, nullaryFunction )
35−import Rel8.Type.Array1D ( Array1D )
3638
3739-- text
3840import Data.Text (Text)
@@ -50,7 +52,7 @@ infixr 6 ++.
5052
5153
5254-- | Matches regular expression, case sensitive
53−--
55+--
5456-- Corresponds to the @~.@ operator.
5557(~.) :: Expr Text -> Expr Text -> Expr Bool
5658(~.) = binaryOperator "~."
@@ -218,7 +220,7 @@ regexpReplace a b c Nothing = function "regexp_replace" a b c
218220
219221-- | Corresponds to the @regexp_split_to_array@ function.
220222regexpSplitToArray :: ()
221− => Expr Text -> Expr Text -> Maybe (Expr Text) -> Expr (Array1D Text)
223+ => Expr Text -> Expr Text -> Maybe (Expr Text) -> Expr [Text]
222224regexpSplitToArray a b (Just c) = function "regexp_split_to_array" a b c
223225regexpSplitToArray a b Nothing = function "regexp_split_to_array" a b
224226
@@ -274,3 +276,21 @@ substr a b Nothing = function "substr" a b
274276-- | Corresponds to the @translate@ function.
275277translate :: Expr Text -> Expr Text -> Expr Text -> Expr Text
276278translate = function "translate"
279+
280+
281+-- | @like x y@ corresponds to the expression @y LIKE x@.
282+--
283+-- Note that the arguments to @like@ are swapped. This is to aid currying, so
284+-- you can write expressions like
285+-- @filter (like "Rel%" . packageName) =<< each haskellPackages@
286+like :: Expr Text -> Expr Text -> Expr Bool
287+like = flip (binaryOperator "LIKE")
288+
289+
290+-- | @ilike x y@ corresponds to the expression @y ILIKE x@.
291+--
292+-- Note that the arguments to @ilike@ are swapped. This is to aid currying, so
293+-- you can write expressions like
294+-- @filter (ilike "Rel%" . packageName) =<< each haskellPackages@
295+ilike :: Expr Text -> Expr Text -> Expr Bool
296+ilike = flip (binaryOperator "ILIKE")
src/Rel8/Expr/Time.hs+2−2
@@ -31,7 +31,7 @@ import Prelude
3131-- rel8
3232import Rel8.Expr ( Expr )
3333import Rel8.Expr.Function ( binaryOperator, nullaryFunction )
34−import Rel8.Expr.Opaleye ( unsafeCastExpr, unsafeLiteral )
34+import Rel8.Expr.Opaleye ( castExpr, unsafeCastExpr, unsafeLiteral )
3535
3636-- time
3737import Data.Time.Calendar ( Day )
@@ -164,4 +164,4 @@ years = (`scaleInterval` year)
164164
165165
166166singleton :: String -> Expr CalendarDiffTime
167−singleton unit = unsafeLiteral $ "'1 " ++ unit ++ "'"
167+singleton unit = castExpr $ unsafeLiteral $ "'1 " ++ unit ++ "'"
src/Rel8/Expr/Window.hsnew file+121
@@ -0,0 +1,121 @@
1+module Rel8.Expr.Window
2+ ( cumulative
3+ , rowNumber
4+ , rank
5+ , denseRank
6+ , percentRank
7+ , cumeDist
8+ , ntile
9+ , lag
10+ , lead
11+ , firstValue
12+ , lastValue
13+ , nthValue
14+ )
15+where
16+
17+-- base
18+import Data.Int ( Int32, Int64 )
19+import Prelude
20+
21+-- opaleye
22+import qualified Opaleye.Internal.Aggregate as Opaleye
23+import qualified Opaleye.Internal.PackMap as Opaleye
24+import qualified Opaleye.Internal.Window as Opaleye
25+import qualified Opaleye.Window as Opaleye
26+
27+-- profunctors
28+import Data.Profunctor (dimap)
29+
30+-- rel8
31+import Rel8.Aggregate ( Aggregate( Aggregate ) )
32+import Rel8.Expr ( Expr )
33+import Rel8.Expr.Opaleye ( fromColumn, fromPrimExpr, toColumn, toPrimExpr )
34+import Rel8.Schema.Null ( Nullify )
35+import Rel8.Window ( Window( Window ) )
36+
37+
38+cumulative :: (a -> Aggregate b) -> Window a (Expr b)
39+cumulative f =
40+ fromWindowFunction $ Opaleye.aggregatorWindowFunction (fromAggregate f) id
41+
42+
43+-- | [@row_number()@](https://www.postgresql.org/docs/current/functions-window.html)
44+rowNumber :: Window a (Expr Int64)
45+rowNumber = fromWindowFunction $ fromPrimExpr . fromColumn <$> Opaleye.rowNumber
46+
47+
48+-- | [@rank()@](https://www.postgresql.org/docs/current/functions-window.html)
49+rank :: Window a (Expr Int64)
50+rank = fromWindowFunction $ fromPrimExpr . fromColumn <$> Opaleye.rank
51+
52+
53+-- | [@dense_rank()@](https://www.postgresql.org/docs/current/functions-window.html)
54+denseRank :: Window a (Expr Int64)
55+denseRank = fromWindowFunction $ fromPrimExpr . fromColumn <$> Opaleye.denseRank
56+
57+
58+-- | [@percent_rank()@](https://www.postgresql.org/docs/current/functions-window.html)
59+percentRank :: Window a (Expr Double)
60+percentRank = fromWindowFunction $ fromPrimExpr . fromColumn <$> Opaleye.percentRank
61+
62+
63+-- | [@cume_dist()@](https://www.postgresql.org/docs/current/functions-window.html)
64+cumeDist :: Window a (Expr Double)
65+cumeDist = fromWindowFunction $ fromPrimExpr . fromColumn <$> Opaleye.cumeDist
66+
67+
68+-- | [@ntile(num_buckets)@](https://www.postgresql.org/docs/current/functions-window.html)
69+ntile :: Expr Int32 -> Window a (Expr Int32)
70+ntile buckets = fromWindowFunction $ fromPrimExpr . fromColumn <$>
71+ Opaleye.ntile (toColumn (toPrimExpr buckets))
72+
73+
74+-- | [@lag(value, offset, default)@](https://www.postgresql.org/docs/current/functions-window.html)
75+lag :: Expr Int32 -> Expr a -> Window (Expr a) (Expr a)
76+lag offset def =
77+ fromWindowFunction $
78+ dimap (toColumn . toPrimExpr) (fromPrimExpr . fromColumn) $
79+ Opaleye.lag (toColumn (toPrimExpr offset)) (toColumn (toPrimExpr def))
80+
81+
82+-- | [@lead(value, offset, default)@](https://www.postgresql.org/docs/current/functions-window.html)
83+lead :: Expr Int32 -> Expr a -> Window (Expr a) (Expr a)
84+lead offset def =
85+ fromWindowFunction $
86+ dimap (toColumn . toPrimExpr) (fromPrimExpr . fromColumn) $
87+ Opaleye.lead (toColumn (toPrimExpr offset)) (toColumn (toPrimExpr def))
88+
89+
90+-- | [@first_value(value)@](https://www.postgresql.org/docs/current/functions-window.html)
91+firstValue :: Window (Expr a) (Expr a)
92+firstValue =
93+ fromWindowFunction $
94+ dimap (toColumn . toPrimExpr) (fromPrimExpr . fromColumn)
95+ Opaleye.firstValue
96+
97+
98+-- | [@last_value(value)@](https://www.postgresql.org/docs/current/functions-window.html)
99+lastValue :: Window (Expr a) (Expr a)
100+lastValue =
101+ fromWindowFunction $
102+ dimap (toColumn . toPrimExpr) (fromPrimExpr . fromColumn)
103+ Opaleye.lastValue
104+
105+
106+-- | [@nth_value(value, n)@](https://www.postgresql.org/docs/current/functions-window.html)
107+nthValue :: Expr Int32 -> Window (Expr a) (Expr (Nullify a))
108+nthValue n =
109+ fromWindowFunction $
110+ dimap (toColumn . toPrimExpr) (fromPrimExpr . fromColumn) $
111+ Opaleye.nthValue (toColumn (toPrimExpr n))
112+
113+
114+fromAggregate :: (a -> Aggregate b) -> Opaleye.Aggregator a (Expr b)
115+fromAggregate f = Opaleye.Aggregator $ Opaleye.PackMap $ \w a -> case f a of
116+ Aggregate (Opaleye.Aggregator (Opaleye.PackMap x)) -> x w ()
117+
118+
119+fromWindowFunction :: Opaleye.WindowFunction a b -> Window a b
120+fromWindowFunction (Opaleye.WindowFunction (Opaleye.PackMap w)) =
121+ Window $ Opaleye.Windows $ Opaleye.PackMap $ \f -> w $ \o -> f (o, mempty)
src/Rel8/FCF.hs+9−1
@@ -3,7 +3,11 @@
33{-# language StandaloneKindSignatures #-}
44{-# language TypeFamilies #-}
55
6−module Rel8.FCF ( Exp, Eval ) where
6+module Rel8.FCF
7+ ( Exp, Eval
8+ , Id
9+ )
10+where
711
812-- base
913import Data.Kind ( Type )
@@ -16,3 +20,7 @@ type Exp e = e -> Type
1620
1721type Eval :: Exp e -> e
1822type family Eval a
23+
24+
25+data Id :: a -> Exp a
26+type instance Eval (Id a) = a
src/Rel8/Generic/Construction.hsnew file+352
@@ -0,0 +1,352 @@
1+{-# language AllowAmbiguousTypes #-}
2+{-# language ConstraintKinds #-}
3+{-# language DataKinds #-}
4+{-# language FlexibleContexts #-}
5+{-# language NamedFieldPuns #-}
6+{-# language ScopedTypeVariables #-}
7+{-# language StandaloneKindSignatures #-}
8+{-# language TypeApplications #-}
9+{-# language TypeFamilies #-}
10+{-# language UndecidableInstances #-}
11+{-# language ViewPatterns #-}
12+
13+module Rel8.Generic.Construction
14+ ( GGBuildable
15+ , GGBuild, ggbuild
16+ , GGConstructable
17+ , GGConstruct, ggconstruct
18+ , GGDeconstruct, ggdeconstruct
19+ , GGName, ggname
20+ , GGAggregate, ggaggregate
21+ )
22+where
23+
24+-- base
25+import Data.Bifunctor ( first )
26+import Data.Kind ( Constraint, Type )
27+import Data.List.NonEmpty ( NonEmpty( (:|) ) )
28+import GHC.TypeLits ( Symbol )
29+import Prelude
30+
31+-- rel8
32+import Rel8.Aggregate ( Aggregate( Aggregate ) )
33+import Rel8.Expr ( Expr )
34+import Rel8.Expr.Aggregate ( groupByExpr )
35+import Rel8.Expr.Eq ( (==.) )
36+import Rel8.Expr.Null ( nullify, snull, unsafeUnnullify )
37+import Rel8.Expr.Serialize ( litExpr )
38+import Rel8.FCF ( Eval, Exp, Id )
39+import Rel8.Generic.Construction.ADT
40+ ( GConstructorADT, GMakeableADT, gmakeADT
41+ , GConstructableADT
42+ , GBuildADT, gbuildADT, gunbuildADT
43+ , GConstructADT, gconstructADT, gdeconstructADT
44+ , RepresentableConstructors, GConstructors, gcindex, gctabulate
45+ , RepresentableFields, gfindex, gftabulate
46+ )
47+import Rel8.Generic.Construction.Record
48+ ( GConstructor
49+ , GConstructable, GConstruct, gconstruct, gdeconstruct
50+ , Representable, gindex, gtabulate
51+ )
52+import Rel8.Generic.Table ( GGColumns )
53+import Rel8.Kind.Algebra
54+ ( SAlgebra( SProduct, SSum )
55+ , KnownAlgebra, algebraSing
56+ )
57+import qualified Rel8.Kind.Algebra as K
58+import Rel8.Schema.Context.Nullify ( sguard, snullify )
59+import Rel8.Schema.HTable ( HTable )
60+import Rel8.Schema.HTable.Identity ( HIdentity( HIdentity ) )
61+import qualified Rel8.Schema.Kind as K
62+import Rel8.Schema.Name ( Name( Name ) )
63+import Rel8.Schema.Null ( Nullity( Null, NotNull ) )
64+import Rel8.Schema.Spec ( Spec( Spec, nullity, info ) )
65+import Rel8.Table
66+ ( TTable, TColumns
67+ , Table, fromColumns, toColumns
68+ )
69+import Rel8.Table.Bool ( case_ )
70+import Rel8.Type.Tag ( Tag )
71+
72+
73+type GGBuildable :: K.Algebra -> Symbol -> (K.Context -> Exp (Type -> Type)) -> Constraint
74+type GGBuildable algebra name rep =
75+ ( KnownAlgebra algebra
76+ , Eval (GGColumns algebra TColumns (Eval (rep Aggregate))) ~ Eval (GGColumns algebra TColumns (Eval (rep Expr)))
77+ , Eval (GGColumns algebra TColumns (Eval (rep Expr))) ~ Eval (GGColumns algebra TColumns (Eval (rep Expr)))
78+ , Eval (GGColumns algebra TColumns (Eval (rep Name))) ~ Eval (GGColumns algebra TColumns (Eval (rep Expr)))
79+ , HTable (Eval (GGColumns algebra TColumns (Eval (rep Expr))))
80+ , GGBuildable' algebra name rep
81+ )
82+
83+
84+type GGBuildable' :: K.Algebra -> Symbol -> (K.Context -> Exp (Type -> Type)) -> Constraint
85+type family GGBuildable' algebra name rep where
86+ GGBuildable' 'K.Product name rep =
87+ ( name ~ GConstructor (Eval (rep Expr))
88+ , Representable Id (Eval (rep Expr))
89+ , GConstructable (TTable Expr) TColumns Id Expr (Eval (rep Expr))
90+ )
91+ GGBuildable' 'K.Sum name rep =
92+ ( Representable Id (GConstructorADT name (Eval (rep Expr)))
93+ , GMakeableADT (TTable Expr) TColumns Id Expr name (Eval (rep Expr))
94+ )
95+
96+
97+type GGBuild :: K.Algebra -> Symbol -> (K.Context -> Exp (Type -> Type)) -> Type -> Type
98+type family GGBuild algebra name rep r where
99+ GGBuild 'K.Product _name rep r =
100+ GConstruct Id (Eval (rep Expr)) r
101+ GGBuild 'K.Sum name rep r =
102+ GConstruct Id (GConstructorADT name (Eval (rep Expr))) r
103+
104+
105+ggbuild :: forall algebra name rep a. GGBuildable algebra name rep
106+ => (Eval (GGColumns algebra TColumns (Eval (rep Expr))) Expr -> a)
107+ -> GGBuild algebra name rep a
108+ggbuild gfromColumns = case algebraSing @algebra of
109+ SProduct ->
110+ gtabulate @Id @(Eval (rep Expr)) @a $
111+ gfromColumns .
112+ gconstruct
113+ @(TTable Expr)
114+ @TColumns
115+ @Id
116+ @Expr
117+ @(Eval (rep Expr))
118+ (const toColumns)
119+ SSum ->
120+ gtabulate @Id @(GConstructorADT name (Eval (rep Expr))) @a $
121+ gfromColumns .
122+ gmakeADT
123+ @(TTable Expr)
124+ @TColumns
125+ @Id
126+ @Expr
127+ @name
128+ @(Eval (rep Expr))
129+ (const toColumns)
130+ (\Spec {info} -> snull info)
131+ (\Spec {nullity} -> case nullity of
132+ Null -> id
133+ NotNull -> nullify)
134+ (HIdentity . litExpr)
135+
136+
137+type GGConstructable :: K.Algebra -> (K.Context -> Exp (Type -> Type)) -> Constraint
138+type GGConstructable algebra rep =
139+ ( KnownAlgebra algebra
140+ , Eval (GGColumns algebra TColumns (Eval (rep Aggregate))) ~ Eval (GGColumns algebra TColumns (Eval (rep Expr)))
141+ , Eval (GGColumns algebra TColumns (Eval (rep Expr))) ~ Eval (GGColumns algebra TColumns (Eval (rep Expr)))
142+ , Eval (GGColumns algebra TColumns (Eval (rep Name))) ~ Eval (GGColumns algebra TColumns (Eval (rep Expr)))
143+ , HTable (Eval (GGColumns algebra TColumns (Eval (rep Expr))))
144+ , GGConstructable' algebra rep
145+ )
146+
147+
148+type GGConstructable' :: K.Algebra -> (K.Context -> Exp (Type -> Type)) -> Constraint
149+type family GGConstructable' algebra rep where
150+ GGConstructable' 'K.Product rep =
151+ ( Representable Id (Eval (rep Aggregate))
152+ , Representable Id (Eval (rep Expr))
153+ , Representable Id (Eval (rep Name))
154+ , GConstructable (TTable Aggregate) TColumns Id Aggregate (Eval (rep Aggregate))
155+ , GConstructable (TTable Expr) TColumns Id Expr (Eval (rep Expr))
156+ , GConstructable (TTable Name) TColumns Id Name (Eval (rep Name))
157+ )
158+ GGConstructable' 'K.Sum rep =
159+ ( RepresentableConstructors Id (Eval (rep Expr))
160+ , RepresentableFields Id (Eval (rep Aggregate))
161+ , RepresentableFields Id (Eval (rep Expr))
162+ , RepresentableFields Id (Eval (rep Name))
163+ , Functor (GConstructors Id (Eval (rep Expr)))
164+ , GConstructableADT (TTable Aggregate) TColumns Id Aggregate (Eval (rep Aggregate))
165+ , GConstructableADT (TTable Expr) TColumns Id Expr (Eval (rep Expr))
166+ , GConstructableADT (TTable Name) TColumns Id Name (Eval (rep Name))
167+ )
168+
169+
170+type GGConstruct :: K.Algebra -> (K.Context -> Exp (Type -> Type)) -> Type -> Type
171+type family GGConstruct algebra rep r where
172+ GGConstruct 'K.Product rep r = GConstruct Id (Eval (rep Expr)) r -> r
173+ GGConstruct 'K.Sum rep r = GConstructADT Id (Eval (rep Expr)) r r
174+
175+
176+ggconstruct :: forall algebra rep a. GGConstructable algebra rep
177+ => (Eval (GGColumns algebra TColumns (Eval (rep Expr))) Expr -> a)
178+ -> GGConstruct algebra rep a -> a
179+ggconstruct gfromColumns f = case algebraSing @algebra of
180+ SProduct ->
181+ f $
182+ gtabulate @Id @(Eval (rep Expr)) @a $
183+ gfromColumns .
184+ gconstruct
185+ @(TTable Expr)
186+ @TColumns
187+ @Id
188+ @Expr
189+ @(Eval (rep Expr))
190+ (const toColumns)
191+ SSum ->
192+ gcindex @Id @(Eval (rep Expr)) @a f $
193+ fmap gfromColumns $
194+ gconstructADT
195+ @(TTable Expr)
196+ @TColumns
197+ @Id
198+ @Expr
199+ @(Eval (rep Expr))
200+ (const toColumns)
201+ (\Spec {info} -> snull info)
202+ (\Spec {nullity} -> case nullity of
203+ Null -> id
204+ NotNull -> nullify)
205+ (HIdentity . litExpr)
206+
207+
208+type GGDeconstruct :: K.Algebra -> (K.Context -> Exp (Type -> Type)) -> Type -> Type -> Type
209+type family GGDeconstruct algebra rep a r where
210+ GGDeconstruct 'K.Product rep a r =
211+ GConstruct Id (Eval (rep Expr)) r -> a -> r
212+ GGDeconstruct 'K.Sum rep a r =
213+ GConstructADT Id (Eval (rep Expr)) r (a -> r)
214+
215+
216+ggdeconstruct :: forall algebra rep a r. (GGConstructable algebra rep, Table Expr r)
217+ => (a -> Eval (GGColumns algebra TColumns (Eval (rep Expr))) Expr)
218+ -> GGDeconstruct algebra rep a r
219+ggdeconstruct gtoColumns = case algebraSing @algebra of
220+ SProduct -> \build ->
221+ gindex @Id @(Eval (rep Expr)) @r build .
222+ gdeconstruct
223+ @(TTable Expr)
224+ @TColumns
225+ @Id
226+ @Expr
227+ @(Eval (rep Expr))
228+ (const fromColumns) .
229+ gtoColumns
230+ SSum ->
231+ gctabulate @Id @(Eval (rep Expr)) @r @(a -> r) $ \constructors as ->
232+ let
233+ (HIdentity tag, cases) =
234+ gdeconstructADT
235+ @(TTable Expr)
236+ @TColumns
237+ @Id
238+ @Expr
239+ @(Eval (rep Expr))
240+ (const fromColumns)
241+ (\Spec {nullity} -> case nullity of
242+ Null -> id
243+ NotNull -> unsafeUnnullify)
244+ constructors $
245+ gtoColumns as
246+ in
247+ case cases of
248+ ((_, r) :| (map (first ((tag ==.) . litExpr)) -> cases')) ->
249+ case_ cases' r
250+
251+
252+type GGName :: K.Algebra -> (K.Context -> Exp (Type -> Type)) -> Type -> Type
253+type family GGName algebra rep a where
254+ GGName 'K.Product rep a = GConstruct Id (Eval (rep Name)) a
255+ GGName 'K.Sum rep a = Name Tag -> GBuildADT Id (Eval (rep Name)) a
256+
257+
258+ggname :: forall algebra rep a. GGConstructable algebra rep
259+ => (Eval (GGColumns algebra TColumns (Eval (rep Expr))) Name -> a)
260+ -> GGName algebra rep a
261+ggname gfromColumns = case algebraSing @algebra of
262+ SProduct ->
263+ gtabulate @Id @(Eval (rep Name)) @a $
264+ gfromColumns .
265+ gconstruct
266+ @(TTable Name)
267+ @TColumns
268+ @Id
269+ @Name
270+ @(Eval (rep Name))
271+ (const toColumns)
272+ SSum -> \tag ->
273+ gftabulate @Id @(Eval (rep Name)) @a $
274+ gfromColumns .
275+ gbuildADT
276+ @(TTable Name)
277+ @TColumns
278+ @Id
279+ @Name
280+ @(Eval (rep Name))
281+ (const toColumns)
282+ (\_ _ (Name a) -> Name a)
283+ (HIdentity tag)
284+
285+
286+type GGAggregate :: K.Algebra -> (K.Context -> Exp (Type -> Type)) -> Type -> Type
287+type family GGAggregate algebra rep r where
288+ GGAggregate 'K.Product rep r =
289+ GConstruct Id (Eval (rep Aggregate)) r ->
290+ GConstruct Id (Eval (rep Expr)) r
291+ GGAggregate 'K.Sum rep r =
292+ GBuildADT Id (Eval (rep Aggregate)) r ->
293+ GBuildADT Id (Eval (rep Expr)) r
294+
295+
296+ggaggregate :: forall algebra rep exprs agg. GGConstructable algebra rep
297+ => (Eval (GGColumns algebra TColumns (Eval (rep Expr))) Aggregate -> agg)
298+ -> (exprs -> Eval (GGColumns algebra TColumns (Eval (rep Expr))) Expr)
299+ -> GGAggregate algebra rep agg -> exprs -> agg
300+ggaggregate gfromColumns gtoColumns agg es = case algebraSing @algebra of
301+ SProduct -> flip f exprs $
302+ gfromColumns .
303+ gconstruct
304+ @(TTable Aggregate)
305+ @TColumns
306+ @Id
307+ @Aggregate
308+ @(Eval (rep Aggregate))
309+ (const toColumns)
310+ where
311+ f =
312+ gindex @Id @(Eval (rep Expr)) @agg .
313+ agg .
314+ gtabulate @Id @(Eval (rep Aggregate)) @agg
315+ exprs =
316+ gdeconstruct
317+ @(TTable Expr)
318+ @TColumns
319+ @Id
320+ @Expr
321+ @(Eval (rep Expr))
322+ (const fromColumns) $
323+ gtoColumns es
324+ SSum -> flip f exprs $
325+ gfromColumns .
326+ gbuildADT
327+ @(TTable Aggregate)
328+ @TColumns
329+ @Id
330+ @Aggregate
331+ @(Eval (rep Aggregate))
332+ (const toColumns)
333+ (\tag' Spec {nullity} (Aggregate a) ->
334+ Aggregate $ sguard (tag ==. litExpr tag') . snullify nullity <$> a)
335+ (HIdentity (groupByExpr tag))
336+ where
337+ f =
338+ gfindex @Id @(Eval (rep Expr)) @agg .
339+ agg .
340+ gftabulate @Id @(Eval (rep Aggregate)) @agg
341+ (HIdentity tag, exprs) =
342+ gunbuildADT
343+ @(TTable Expr)
344+ @TColumns
345+ @Id
346+ @Expr
347+ @(Eval (rep Expr))
348+ (const fromColumns)
349+ (\Spec {nullity} -> case nullity of
350+ Null -> id
351+ NotNull -> unsafeUnnullify) $
352+ gtoColumns es
src/Rel8/Generic/Construction/ADT.hsnew file+478
@@ -0,0 +1,478 @@
1+{-# language AllowAmbiguousTypes #-}
2+{-# language BlockArguments #-}
3+{-# language DataKinds #-}
4+{-# language FlexibleContexts #-}
5+{-# language FlexibleInstances #-}
6+{-# language MultiParamTypeClasses #-}
7+{-# language RankNTypes #-}
8+{-# language ScopedTypeVariables #-}
9+{-# language StandaloneKindSignatures #-}
10+{-# language TupleSections #-}
11+{-# language TypeApplications #-}
12+{-# language TypeFamilies #-}
13+{-# language TypeOperators #-}
14+{-# language UndecidableInstances #-}
15+
16+module Rel8.Generic.Construction.ADT
17+ ( GConstructableADT
18+ , GBuildADT, gbuildADT, gunbuildADT
19+ , GConstructADT, gconstructADT, gdeconstructADT
20+ , GFields, RepresentableFields, gftabulate, gfindex
21+ , GConstructors, RepresentableConstructors, gctabulate, gcindex
22+ , GConstructorADT, GMakeableADT, gmakeADT
23+ )
24+where
25+
26+-- base
27+import Data.Bifunctor ( first )
28+import Data.Functor.Identity ( runIdentity )
29+import Data.Kind ( Constraint, Type )
30+import Data.List.NonEmpty ( NonEmpty )
31+import Data.Proxy ( Proxy( Proxy ) )
32+import GHC.Generics
33+ ( (:+:), (:*:)( (:*:) ), M1, U1
34+ , C, D
35+ , Meta( MetaData, MetaCons )
36+ )
37+import GHC.TypeLits
38+ ( ErrorMessage( (:<>:), Text ), TypeError
39+ , Symbol, KnownSymbol, symbolVal
40+ )
41+import Prelude hiding ( null )
42+
43+-- rel8
44+import Rel8.FCF ( Exp )
45+import Rel8.Generic.Construction.Record
46+ ( GConstruct, GConstructable, gconstruct, gdeconstruct
47+ , GFields, Representable, gtabulate, gindex
48+ , FromColumns, ToColumns
49+ )
50+import Rel8.Generic.Table.ADT ( GColumnsADT, GColumnsADT' )
51+import Rel8.Generic.Table.Record ( GColumns )
52+import Rel8.Schema.HTable ( HTable )
53+import Rel8.Schema.HTable.Identity ( HIdentity )
54+import Rel8.Schema.HTable.Label ( HLabel, hlabel, hunlabel )
55+import Rel8.Schema.HTable.Nullify ( HNullify, hnulls, hnullify, hunnullify )
56+import Rel8.Schema.HTable.Product ( HProduct( HProduct ) )
57+import Rel8.Schema.Null ( Nullify )
58+import Rel8.Schema.Spec ( Spec )
59+import qualified Rel8.Schema.Kind as K
60+import Rel8.Type.Tag ( Tag( Tag ) )
61+
62+-- text
63+import Data.Text ( pack )
64+
65+
66+type Null :: K.Context -> Type
67+type Null context = forall a. Spec a -> context (Nullify a)
68+
69+
70+type Nullifier :: K.Context -> Type
71+type Nullifier context = forall a. Spec a -> context a -> context (Nullify a)
72+
73+
74+type Unnullifier :: K.Context -> Type
75+type Unnullifier context = forall a. Spec a -> context (Nullify a) -> context a
76+
77+
78+type NoConstructor :: Symbol -> Symbol -> ErrorMessage
79+type NoConstructor datatype constructor =
80+ ( 'Text "The type `" ':<>:
81+ 'Text datatype ':<>:
82+ 'Text "` has no constructor `" ':<>:
83+ 'Text constructor ':<>:
84+ 'Text "`."
85+ )
86+
87+
88+type GConstructorADT :: Symbol -> (Type -> Type) -> Type -> Type
89+type family GConstructorADT name rep where
90+ GConstructorADT name (M1 D ('MetaData datatype _ _ _) rep) =
91+ GConstructorADT' name rep (TypeError (NoConstructor datatype name))
92+
93+
94+type GConstructorADT' :: Symbol -> (Type -> Type) -> (Type -> Type) -> Type -> Type
95+type family GConstructorADT' name rep fallback where
96+ GConstructorADT' name (M1 D _ rep) fallback =
97+ GConstructorADT' name rep fallback
98+ GConstructorADT' name (a :+: b) fallback =
99+ GConstructorADT' name a (GConstructorADT' name b fallback)
100+ GConstructorADT' name (M1 C ('MetaCons name _ _) rep) _ = rep
101+ GConstructorADT' _ _ fallback = fallback
102+
103+
104+type GConstructADT
105+ :: (Type -> Exp Type)
106+ -> (Type -> Type) -> Type -> Type -> Type
107+type family GConstructADT f rep r x where
108+ GConstructADT f (M1 D _ rep) r x = GConstructADT f rep r x
109+ GConstructADT f (a :+: b) r x = GConstructADT f a r (GConstructADT f b r x)
110+ GConstructADT f (M1 C _ rep) r x = GConstruct f rep r -> x
111+
112+
113+type GConstructors :: (Type -> Exp Type) -> (Type -> Type) -> Type -> Type
114+type family GConstructors f rep where
115+ GConstructors f (M1 D _ rep) = GConstructors f rep
116+ GConstructors f (a :+: b) = GConstructors f a :*: GConstructors f b
117+ GConstructors f (M1 C _ rep) = (->) (GFields f rep)
118+
119+
120+type RepresentableConstructors :: (Type -> Exp Type) -> (Type -> Type) -> Constraint
121+class RepresentableConstructors f rep where
122+ gctabulate :: (GConstructors f rep r -> a) -> GConstructADT f rep r a
123+ gcindex :: GConstructADT f rep r a -> GConstructors f rep r -> a
124+
125+
126+instance RepresentableConstructors f rep => RepresentableConstructors f (M1 D meta rep) where
127+ gctabulate = gctabulate @f @rep
128+ gcindex = gcindex @f @rep
129+
130+
131+instance (RepresentableConstructors f a, RepresentableConstructors f b) =>
132+ RepresentableConstructors f (a :+: b)
133+ where
134+ gctabulate f =
135+ gctabulate @f @a \a -> gctabulate @f @b \b -> f (a :*: b)
136+ gcindex f (a :*: b) = gcindex @f @b (gcindex @f @a f a) b
137+
138+
139+instance Representable f rep => RepresentableConstructors f (M1 C meta rep) where
140+ gctabulate f = f . gindex @f @rep
141+ gcindex f = f . gtabulate @f @rep
142+
143+
144+type GBuildADT :: (Type -> Exp Type) -> (Type -> Type) -> Type -> Type
145+type family GBuildADT f rep r where
146+ GBuildADT f (M1 D _ rep) r = GBuildADT f rep r
147+ GBuildADT f (a :+: b) r = GBuildADT f a (GBuildADT f b r)
148+ GBuildADT f (M1 C _ rep) r = GConstruct f rep r
149+
150+
151+type GFieldsADT :: (Type -> Exp Type) -> (Type -> Type) -> Type
152+type family GFieldsADT f rep where
153+ GFieldsADT f (M1 D _ rep) = GFieldsADT f rep
154+ GFieldsADT f (a :+: b) = (GFieldsADT f a, GFieldsADT f b)
155+ GFieldsADT f (M1 C _ rep) = GFields f rep
156+
157+
158+type RepresentableFields :: (Type -> Exp Type) -> (Type -> Type) -> Constraint
159+class RepresentableFields f rep where
160+ gftabulate :: (GFieldsADT f rep -> a) -> GBuildADT f rep a
161+ gfindex :: GBuildADT f rep a -> GFieldsADT f rep -> a
162+
163+
164+instance RepresentableFields f rep => RepresentableFields f (M1 D meta rep) where
165+ gftabulate = gftabulate @f @rep
166+ gfindex = gfindex @f @rep
167+
168+
169+instance (RepresentableFields f a, RepresentableFields f b) => RepresentableFields f (a :+: b) where
170+ gftabulate f =
171+ gftabulate @f @a \a -> gftabulate @f @b \b -> f (a, b)
172+ gfindex f (a, b) = gfindex @f @b (gfindex @f @a f a) b
173+
174+
175+instance Representable f rep => RepresentableFields f (M1 C meta rep) where
176+ gftabulate = gtabulate @f @rep
177+ gfindex = gindex @f @rep
178+
179+
180+type GConstructableADT
181+ :: (Type -> Exp Constraint)
182+ -> (Type -> Exp K.HTable)
183+ -> (Type -> Exp Type)
184+ -> K.Context -> (Type -> Type) -> Constraint
185+class GConstructableADT _Table _Columns f context rep where
186+ gbuildADT :: ()
187+ => ToColumns _Table _Columns f context
188+ -> (Tag -> Nullifier context)
189+ -> HIdentity Tag context
190+ -> GFieldsADT f rep
191+ -> GColumnsADT _Columns rep context
192+
193+ gunbuildADT :: ()
194+ => FromColumns _Table _Columns f context
195+ -> Unnullifier context
196+ -> GColumnsADT _Columns rep context
197+ -> (HIdentity Tag context, GFieldsADT f rep)
198+
199+ gconstructADT :: ()
200+ => ToColumns _Table _Columns f context
201+ -> Null context
202+ -> Nullifier context
203+ -> (Tag -> HIdentity Tag context)
204+ -> GConstructors f rep (GColumnsADT _Columns rep context)
205+
206+ gdeconstructADT :: ()
207+ => FromColumns _Table _Columns f context
208+ -> Unnullifier context
209+ -> GConstructors f rep r
210+ -> GColumnsADT _Columns rep context
211+ -> (HIdentity Tag context, NonEmpty (Tag, r))
212+
213+
214+instance
215+ ( htable ~ HLabel "tag" (HIdentity Tag)
216+ , GConstructableADT' _Table _Columns f context htable rep
217+ )
218+ => GConstructableADT _Table _Columns f context (M1 D meta rep)
219+ where
220+ gbuildADT toColumns nullifier =
221+ gbuildADT' @_Table @_Columns @f @context @htable @rep toColumns nullifier .
222+ hlabel
223+
224+ gunbuildADT fromColumns unnullifier =
225+ first hunlabel .
226+ gunbuildADT' @_Table @_Columns @f @context @htable @rep fromColumns unnullifier
227+
228+ gconstructADT toColumns null nullifier mk =
229+ gconstructADT' @_Table @_Columns @f @context @htable @rep toColumns null nullifier
230+ (hlabel . mk)
231+
232+ gdeconstructADT fromColumns unnullifier cases =
233+ first hunlabel .
234+ gdeconstructADT' @_Table @_Columns @f @context @htable @rep fromColumns unnullifier cases
235+
236+
237+type GConstructableADT'
238+ :: (Type -> Exp Constraint)
239+ -> (Type -> Exp K.HTable)
240+ -> (Type -> Exp Type)
241+ -> K.Context -> K.HTable -> (Type -> Type) -> Constraint
242+class GConstructableADT' _Table _Columns f context htable rep where
243+ gbuildADT' :: ()
244+ => ToColumns _Table _Columns f context
245+ -> (Tag -> Nullifier context)
246+ -> htable context
247+ -> GFieldsADT f rep
248+ -> GColumnsADT' _Columns htable rep context
249+
250+ gunbuildADT' :: ()
251+ => FromColumns _Table _Columns f context
252+ -> Unnullifier context
253+ -> GColumnsADT' _Columns htable rep context
254+ -> (htable context, GFieldsADT f rep)
255+
256+ gconstructADT' :: ()
257+ => ToColumns _Table _Columns f context
258+ -> Null context
259+ -> Nullifier context
260+ -> (Tag -> htable context)
261+ -> GConstructors f rep (GColumnsADT' _Columns htable rep context)
262+
263+ gdeconstructADT' :: ()
264+ => FromColumns _Table _Columns f context
265+ -> Unnullifier context
266+ -> GConstructors f rep r
267+ -> GColumnsADT' _Columns htable rep context
268+ -> (htable context, NonEmpty (Tag, r))
269+
270+ gfill :: ()
271+ => Null context
272+ -> htable context
273+ -> GColumnsADT' _Columns htable rep context
274+
275+
276+instance
277+ ( htable' ~ GColumnsADT' _Columns htable a
278+ , Functor (GConstructors f a)
279+ , GConstructableADT' _Table _Columns f context htable a
280+ , GConstructableADT' _Table _Columns f context htable' b
281+ )
282+ => GConstructableADT' _Table _Columns f context htable (a :+: b)
283+ where
284+ gbuildADT' toColumns nullifier htable (a, b) =
285+ gbuildADT' @_Table @_Columns @f @context @htable' @b toColumns nullifier
286+ (gbuildADT' @_Table @_Columns @f @context @htable @a toColumns nullifier htable a)
287+ b
288+
289+ gunbuildADT' fromColumns unnullifier columns =
290+ case gunbuildADT' @_Table @_Columns @f @context @htable' @b fromColumns unnullifier columns of
291+ (htable', b) ->
292+ case gunbuildADT' @_Table @_Columns @f @context @htable @a fromColumns unnullifier htable' of
293+ (htable, a) -> (htable, (a, b))
294+
295+ gconstructADT' toColumns null nullifier mk =
296+ fmap (gfill @_Table @_Columns @f @context @htable' @b null) (gconstructADT' @_Table @_Columns @f @context @htable @a toColumns null nullifier mk) :*:
297+ gconstructADT' @_Table @_Columns @f @context @htable' @b toColumns null nullifier (gfill @_Table @_Columns @f @context @htable @a null . mk)
298+
299+ gdeconstructADT' fromColumns unnullifier (a :*: b) columns =
300+ case gdeconstructADT' @_Table @_Columns @f @context @htable' @b fromColumns unnullifier b columns of
301+ (htable', cases) ->
302+ case gdeconstructADT' @_Table @_Columns @f @context @htable @a fromColumns unnullifier a htable' of
303+ (htable, cases') -> (htable, cases' <> cases)
304+
305+ gfill null =
306+ gfill @_Table @_Columns @f @context @htable' @b null .
307+ gfill @_Table @_Columns @f @context @htable @a null
308+
309+
310+instance (meta ~ 'MetaCons label _fixity _isRecord, KnownSymbol label) =>
311+ GConstructableADT' _Table _Columns f context htable (M1 C meta U1)
312+ where
313+ gbuildADT' _ _ = const
314+ gunbuildADT' _ _ = (, ())
315+ gconstructADT' _ _ _ f _ = f tag
316+ where
317+ tag = Tag $ pack $ symbolVal (Proxy @label)
318+ gdeconstructADT' _ _ r htable = (htable, pure (tag, r ()))
319+ where
320+ tag = Tag $ pack $ symbolVal (Proxy @label)
321+ gfill _ = id
322+
323+
324+instance {-# OVERLAPPABLE #-}
325+ ( HTable (GColumns _Columns rep)
326+ , KnownSymbol label
327+ , meta ~ 'MetaCons label _fixity _isRecord
328+ , GConstructable _Table _Columns f context rep
329+ , GColumnsADT' _Columns htable (M1 C meta rep) ~
330+ HProduct htable (HLabel label (HNullify (GColumns _Columns rep)))
331+ )
332+ => GConstructableADT' _Table _Columns f context htable (M1 C meta rep)
333+ where
334+ gbuildADT' toColumns nullifier htable =
335+ HProduct htable .
336+ hlabel .
337+ hnullify (nullifier tag) .
338+ gconstruct @_Table @_Columns @f @context @rep toColumns
339+ where
340+ tag = Tag $ pack $ symbolVal (Proxy @label)
341+
342+ gunbuildADT' fromColumns unnullifier (HProduct htable a) =
343+ ( htable
344+ , gdeconstruct @_Table @_Columns @f @context @rep fromColumns $
345+ runIdentity $
346+ hunnullify (\spec -> pure . unnullifier spec) $
347+ hunlabel
348+ a
349+ )
350+
351+ gconstructADT' toColumns _ nullifier mk =
352+ HProduct htable .
353+ hlabel .
354+ hnullify nullifier .
355+ gconstruct @_Table @_Columns @f @context @rep toColumns
356+ where
357+ tag = Tag $ pack $ symbolVal (Proxy @label)
358+ htable = mk tag
359+
360+ gdeconstructADT' fromColumns unnullifier r (HProduct htable columns) =
361+ ( htable
362+ , pure (tag, r a)
363+ )
364+ where
365+ a = gdeconstruct @_Table @_Columns @f @context @rep fromColumns $
366+ runIdentity $
367+ hunnullify (\spec -> pure . unnullifier spec) $
368+ hunlabel
369+ columns
370+ tag = Tag $ pack $ symbolVal (Proxy @label)
371+
372+ gfill null htable = HProduct htable (hlabel (hnulls null))
373+
374+
375+type GMakeableADT
376+ :: (Type -> Exp Constraint)
377+ -> (Type -> Exp K.HTable)
378+ -> (Type -> Exp Type)
379+ -> K.Context -> Symbol -> (Type -> Type) -> Constraint
380+class GMakeableADT _Table _Columns f context name rep where
381+ gmakeADT :: ()
382+ => ToColumns _Table _Columns f context
383+ -> Null context
384+ -> Nullifier context
385+ -> (Tag -> HIdentity Tag context)
386+ -> GFields f (GConstructorADT name rep)
387+ -> GColumnsADT _Columns rep context
388+
389+
390+instance
391+ ( htable ~ HLabel "tag" (HIdentity Tag)
392+ , meta ~ 'MetaData datatype _module _package _newtype
393+ , fallback ~ TypeError (NoConstructor datatype name)
394+ , fields ~ GFields f (GConstructorADT' name rep fallback)
395+ , GMakeableADT' _Table _Columns f context htable name rep fields
396+ , KnownSymbol name
397+ )
398+ => GMakeableADT _Table _Columns f context name (M1 D meta rep)
399+ where
400+ gmakeADT toColumns null nullifier wrap =
401+ gmakeADT'
402+ @_Table @_Columns @f @context @htable @name @rep @fields
403+ toColumns null nullifier htable
404+ where
405+ tag = Tag $ pack $ symbolVal (Proxy @name)
406+ htable = hlabel (wrap tag)
407+
408+
409+type GMakeableADT'
410+ :: (Type -> Exp Constraint)
411+ -> (Type -> Exp K.HTable)
412+ -> (Type -> Exp Type)
413+ -> K.Context -> K.HTable -> Symbol -> (Type -> Type) -> Type -> Constraint
414+class GMakeableADT' _Table _Columns f context htable name rep fields where
415+ gmakeADT' :: ()
416+ => ToColumns _Table _Columns f context
417+ -> Null context
418+ -> Nullifier context
419+ -> htable context
420+ -> fields
421+ -> GColumnsADT' _Columns htable rep context
422+
423+
424+instance
425+ ( htable' ~ GColumnsADT' _Columns htable a
426+ , GMakeableADT' _Table _Columns f context htable name a fields
427+ , GMakeableADT' _Table _Columns f context htable' name b fields
428+ )
429+ => GMakeableADT' _Table _Columns f context htable name (a :+: b) fields
430+ where
431+ gmakeADT' toColumns null nullifier htable x =
432+ gmakeADT' @_Table @_Columns @f @context @htable' @name @b @fields
433+ toColumns null nullifier
434+ (gmakeADT'
435+ @_Table @_Columns @f @context @htable @name @a @fields toColumns
436+ null nullifier htable x)
437+ x
438+
439+
440+instance {-# OVERLAPPING #-}
441+ GMakeableADT' _Table _Columns f context htable name (M1 C ('MetaCons name _fixity _isRecord) U1) fields
442+ where
443+ gmakeADT' _ _ _ = const
444+
445+
446+instance {-# OVERLAPS #-}
447+ GMakeableADT' _Table _Columns f context htable name (M1 C ('MetaCons label _fixity _isRecord) U1) fields
448+ where
449+ gmakeADT' _ _ _ = const
450+
451+
452+instance {-# OVERLAPS #-}
453+ ( HTable (GColumns _Columns rep)
454+ , GConstructable _Table _Columns f context rep
455+ , fields ~ GFields f rep
456+ , GColumnsADT' _Columns htable (M1 C ('MetaCons name _fixity _isRecord) rep) ~
457+ HProduct htable (HLabel name (HNullify (GColumns _Columns rep)))
458+ )
459+ => GMakeableADT' _Table _Columns f context htable name (M1 C ('MetaCons name _fixity _isRecord) rep) fields
460+ where
461+ gmakeADT' toColumns _ nullifier htable =
462+ HProduct htable .
463+ hlabel .
464+ hnullify nullifier .
465+ gconstruct @_Table @_Columns @f @context @rep toColumns
466+
467+
468+instance {-# OVERLAPPABLE #-}
469+ ( HTable (GColumns _Columns rep)
470+ , GColumnsADT' _Columns htable (M1 C ('MetaCons label _fixity _isRecord) rep) ~
471+ HProduct htable (HLabel label (HNullify (GColumns _Columns rep)))
472+ )
473+ => GMakeableADT' _Table _Columns f context htable name (M1 C ('MetaCons label _fixity _isRecord) rep) fields
474+ where
475+ gmakeADT' _ null _ htable _ =
476+ HProduct htable $
477+ hlabel $
478+ hnulls null
src/Rel8/Generic/Construction/Record.hsnew file+168
@@ -0,0 +1,168 @@
1+{-# language AllowAmbiguousTypes #-}
2+{-# language BlockArguments #-}
3+{-# language DataKinds #-}
4+{-# language FlexibleInstances #-}
5+{-# language MultiParamTypeClasses #-}
6+{-# language RankNTypes #-}
7+{-# language ScopedTypeVariables #-}
8+{-# language StandaloneKindSignatures #-}
9+{-# language TypeApplications #-}
10+{-# language TypeFamilies #-}
11+{-# language TypeOperators #-}
12+{-# language UndecidableInstances #-}
13+
14+module Rel8.Generic.Construction.Record
15+ ( GConstructor, GConstruct, GConstructable, gconstruct, gdeconstruct
16+ , GFields, Representable, gtabulate, gindex
17+ , FromColumns, ToColumns
18+ )
19+where
20+
21+-- base
22+import Data.Kind ( Constraint, Type )
23+import Data.Proxy ( Proxy( Proxy ) )
24+import GHC.Generics
25+ ( (:*:), K1, M1, U1
26+ , D, C, S, Meta( MetaData, MetaCons, MetaSel )
27+ )
28+import GHC.TypeLits
29+ ( ErrorMessage( (:<>:), Text ), TypeError
30+ , Symbol
31+ )
32+import Prelude
33+
34+-- rel8
35+import Rel8.FCF ( Eval, Exp )
36+import Rel8.Generic.Table.Record ( GColumns )
37+import Rel8.Schema.HTable.Label ( hlabel, hunlabel )
38+import Rel8.Schema.HTable.Product ( HProduct( HProduct ) )
39+import qualified Rel8.Schema.Kind as K
40+
41+
42+type FromColumns
43+ :: (Type -> Exp Constraint)
44+ -> (Type -> Exp K.HTable)
45+ -> (Type -> Exp Type)
46+ -> K.Context
47+ -> Type
48+type FromColumns _Table _Columns f context = forall proxy x.
49+ Eval (_Table x) => proxy x -> Eval (_Columns x) context -> Eval (f x)
50+
51+
52+type ToColumns
53+ :: (Type -> Exp Constraint)
54+ -> (Type -> Exp K.HTable)
55+ -> (Type -> Exp Type)
56+ -> K.Context
57+ -> Type
58+type ToColumns _Table _Columns f context = forall proxy x.
59+ Eval (_Table x) => proxy x -> Eval (f x) -> Eval (_Columns x) context
60+
61+
62+type GConstructor :: (Type -> Type) -> Symbol
63+type family GConstructor rep where
64+ GConstructor (M1 D _ (M1 C ('MetaCons name _ _) _)) = name
65+ GConstructor (M1 D ('MetaData name _ _ _) _) = TypeError (
66+ 'Text "`" ':<>:
67+ 'Text name ':<>:
68+ 'Text "` does not appear to have exactly 1 constructor"
69+ )
70+
71+
72+type GConstruct :: (Type -> Exp Type) -> (Type -> Type) -> Type -> Type
73+type family GConstruct f rep r where
74+ GConstruct f (M1 _ _ rep) r = GConstruct f rep r
75+ GConstruct f (a :*: b) r = GConstruct f a (GConstruct f b r)
76+ GConstruct _ U1 r = r
77+ GConstruct f (K1 _ a) r = Eval (f a) -> r
78+
79+
80+type GFields :: (Type -> Exp Type) -> (Type -> Type) -> Type
81+type family GFields f rep where
82+ GFields f (M1 _ _ rep) = GFields f rep
83+ GFields f (a :*: b) = (GFields f a, GFields f b)
84+ GFields _ U1 = ()
85+ GFields f (K1 _ a) = Eval (f a)
86+
87+
88+type Representable :: (Type -> Exp Type) -> (Type -> Type) -> Constraint
89+class Representable f rep where
90+ gtabulate :: (GFields f rep -> a) -> GConstruct f rep a
91+ gindex :: GConstruct f rep a -> GFields f rep -> a
92+
93+
94+instance Representable f rep => Representable f (M1 i meta rep) where
95+ gtabulate = gtabulate @f @rep
96+ gindex = gindex @f @rep
97+
98+
99+instance (Representable f a, Representable f b) =>
100+ Representable f (a :*: b)
101+ where
102+ gtabulate f = gtabulate @f @a \a -> gtabulate @f @b \b -> f (a, b)
103+ gindex f (a, b) = gindex @f @b (gindex @f @a f a) b
104+
105+
106+instance Representable f U1 where
107+ gtabulate = ($ ())
108+ gindex = const
109+
110+
111+instance Representable f (K1 i a) where
112+ gtabulate = id
113+ gindex = id
114+
115+
116+type GConstructable
117+ :: (Type -> Exp Constraint)
118+ -> (Type -> Exp K.HTable)
119+ -> (Type -> Exp Type)
120+ -> K.Context -> (Type -> Type) -> Constraint
121+class GConstructable _Table _Columns f context rep where
122+ gconstruct :: ()
123+ => ToColumns _Table _Columns f context
124+ -> GFields f rep
125+ -> GColumns _Columns rep context
126+ gdeconstruct :: ()
127+ => FromColumns _Table _Columns f context
128+ -> GColumns _Columns rep context
129+ -> GFields f rep
130+
131+
132+instance (GConstructable _Table _Columns f context rep) =>
133+ GConstructable _Table _Columns f context (M1 D meta rep)
134+ where
135+ gconstruct = gconstruct @_Table @_Columns @f @context @rep
136+ gdeconstruct = gdeconstruct @_Table @_Columns @f @context @rep
137+
138+
139+instance (GConstructable _Table _Columns f context rep) =>
140+ GConstructable _Table _Columns f context (M1 C meta rep)
141+ where
142+ gconstruct = gconstruct @_Table @_Columns @f @context @rep
143+ gdeconstruct = gdeconstruct @_Table @_Columns @f @context @rep
144+
145+
146+instance
147+ ( GConstructable _Table _Columns f context a
148+ , GConstructable _Table _Columns f context b
149+ )
150+ => GConstructable _Table _Columns f context (a :*: b)
151+ where
152+ gconstruct toColumns (a, b) = HProduct
153+ (gconstruct @_Table @_Columns @f @context @a toColumns a)
154+ (gconstruct @_Table @_Columns @f @context @b toColumns b)
155+ gdeconstruct fromColumns (HProduct a b) =
156+ ( gdeconstruct @_Table @_Columns @f @context @a fromColumns a
157+ , gdeconstruct @_Table @_Columns @f @context @b fromColumns b
158+ )
159+
160+
161+instance
162+ ( Eval (_Table a)
163+ , meta ~ 'MetaSel ('Just label) _su _ss _ds
164+ )
165+ => GConstructable _Table _Columns f context (M1 S meta (K1 i a))
166+ where
167+ gconstruct toColumns = hlabel . toColumns (Proxy @a)
168+ gdeconstruct fromColumns = fromColumns (Proxy @a) . hunlabel
src/Rel8/Generic/Map.hsnew file+49
@@ -0,0 +1,49 @@
1+{-# language DataKinds #-}
2+{-# language StandaloneKindSignatures #-}
3+{-# language TypeFamilies #-}
4+{-# language TypeOperators #-}
5+{-# language UndecidableInstances #-}
6+
7+module Rel8.Generic.Map
8+ ( GMap
9+ , Map
10+ )
11+where
12+
13+-- base
14+import Data.Kind ( Type )
15+import GHC.Generics
16+ ( (:+:), (:*:), K1, M1, U1, V1
17+ )
18+import Prelude ()
19+
20+-- rel8
21+import Rel8.FCF ( Eval, Exp )
22+
23+
24+type GMap :: (Type -> Exp Type) -> (Type -> Type) -> Type -> Type
25+type family GMap f rep where
26+ GMap f (M1 i c rep) = M1 i c (GMap f rep)
27+ GMap _ V1 = V1
28+ GMap f (rep1 :+: rep2) = GMap f rep1 :+: GMap f rep2
29+ GMap _ U1 = U1
30+ GMap f (rep1 :*: rep2) = GMap f rep1 :*: GMap f rep2
31+ GMap f (K1 i a) = K1 i (Eval (f a))
32+
33+
34+-- | Map a @Type -> Type@ function over the @Type@-kinded type variables in
35+-- of a type constructor.
36+type Map :: (Type -> Exp Type) -> Type -> Type
37+type family Map f a where
38+ Map p (t a b c d e f g) =
39+ t (Eval (p a)) (Eval (p b)) (Eval (p c)) (Eval (p d)) (Eval (p e))
40+ (Eval (p f)) (Eval (p g))
41+ Map p (t a b c d e f) =
42+ t (Eval (p a)) (Eval (p b)) (Eval (p c)) (Eval (p d)) (Eval (p e))
43+ (Eval (p f))
44+ Map p (t a b c d e) =
45+ t (Eval (p a)) (Eval (p b)) (Eval (p c)) (Eval (p d)) (Eval (p e))
46+ Map p (t a b c d) = t (Eval (p a)) (Eval (p b)) (Eval (p c)) (Eval (p d))
47+ Map p (t a b c) = t (Eval (p a)) (Eval (p b)) (Eval (p c))
48+ Map p (t a b) = t (Eval (p a)) (Eval (p b))
49+ Map p (t a) = t (Eval (p a))
src/Rel8/Generic/Record.hs+31−28
@@ -1,5 +1,6 @@
11{-# language AllowAmbiguousTypes #-}
22{-# language DataKinds #-}
3+{-# language FlexibleContexts #-}
34{-# language FlexibleInstances #-}
45{-# language MultiParamTypeClasses #-}
56{-# language PolyKinds #-}
@@ -12,6 +13,7 @@
1213
1314module Rel8.Generic.Record
1415 ( Record(..)
16+ , GRecordable, GRecord, grecord, gunrecord
1517 )
1618where
1719
@@ -26,13 +28,13 @@ import GHC.TypeLits ( type (+), AppendSymbol, Div, Mod, Nat, Symbol )
2628import Prelude hiding ( Show )
2729
2830
29−type Recordize :: (Type -> Type) -> Type -> Type
30−type family Recordize rep where
31− Recordize (M1 D meta rep) = M1 D meta (Recordize rep)
32− Recordize (l :+: r) = Recordize l :+: Recordize r
33− Recordize (M1 C ('MetaCons name fixity 'False) rep) =
31+type GRecord :: (Type -> Type) -> Type -> Type
32+type family GRecord rep where
33+ GRecord (M1 D meta rep) = M1 D meta (GRecord rep)
34+ GRecord (l :+: r) = GRecord l :+: GRecord r
35+ GRecord (M1 C ('MetaCons name fixity 'False) rep) =
3436 M1 C ('MetaCons name fixity 'True) (Snd (Count 0 rep))
35− Recordize rep = rep
37+ GRecord rep = rep
3638
3739
3840type Count :: Nat -> (Type -> Type) -> (Nat, Type -> Type)
@@ -83,34 +85,34 @@ type family Snd tuple where
8385 Snd '(_a, b) = b
8486
8587
86−type Recordizable :: (Type -> Type) -> Constraint
87−class Recordizable rep where
88− recordize :: rep x -> Recordize rep x
89− unrecordize :: Recordize rep x -> rep x
88+type GRecordable :: (Type -> Type) -> Constraint
89+class GRecordable rep where
90+ grecord :: rep x -> GRecord rep x
91+ gunrecord :: GRecord rep x -> rep x
9092
9193
92−instance Recordizable rep => Recordizable (M1 D meta rep) where
93− recordize (M1 a) = M1 (recordize a)
94− unrecordize (M1 a) = M1 (unrecordize a)
94+instance GRecordable rep => GRecordable (M1 D meta rep) where
95+ grecord (M1 a) = M1 (grecord a)
96+ gunrecord (M1 a) = M1 (gunrecord a)
9597
9698
97−instance (Recordizable l, Recordizable r) => Recordizable (l :+: r) where
98− recordize (L1 a) = L1 (recordize a)
99− recordize (R1 a) = R1 (recordize a)
100− unrecordize (L1 a) = L1 (unrecordize a)
101− unrecordize (R1 a) = R1 (unrecordize a)
99+instance (GRecordable l, GRecordable r) => GRecordable (l :+: r) where
100+ grecord (L1 a) = L1 (grecord a)
101+ grecord (R1 a) = R1 (grecord a)
102+ gunrecord (L1 a) = L1 (gunrecord a)
103+ gunrecord (R1 a) = R1 (gunrecord a)
102104
103105
104106instance Countable 0 rep =>
105− Recordizable (M1 C ('MetaCons name fixity 'False) rep)
107+ GRecordable (M1 C ('MetaCons name fixity 'False) rep)
106108 where
107− recordize (M1 a) = M1 (count @0 a)
108− unrecordize (M1 a) = M1 (uncount @0 a)
109+ grecord (M1 a) = M1 (count @0 a)
110+ gunrecord (M1 a) = M1 (uncount @0 a)
109111
110112
111−instance {-# OVERLAPPABLE #-} Recordize rep ~ rep => Recordizable rep where
112− recordize = id
113− unrecordize = id
113+instance {-# OVERLAPPABLE #-} GRecord rep ~ rep => GRecordable rep where
114+ grecord = id
115+ gunrecord = id
114116
115117
116118type Countable :: Nat -> (Type -> Type) -> Constraint
@@ -140,13 +142,14 @@ instance {-# OVERLAPPABLE #-} Snd (Count n rep) ~ rep => Countable n rep where
140142 uncount = id
141143
142144
145+type Record :: Type -> Type
143146newtype Record a = Record
144147 { unrecord :: a
145148 }
146149
147150
148−instance (Generic a, Recordizable (Rep a)) => Generic (Record a) where
149− type Rep (Record a) = Recordize (Rep a)
151+instance (Generic a, GRecordable (Rep a)) => Generic (Record a) where
152+ type Rep (Record a) = GRecord (Rep a)
150153
151− from (Record a) = recordize (from a)
152− to = Record . to . unrecordize
154+ from (Record a) = grecord (from a)
155+ to = Record . to . gunrecord
src/Rel8/Generic/Rel8able.hsnew file+281
@@ -0,0 +1,281 @@
1+{-# language AllowAmbiguousTypes #-}
2+{-# language ConstraintKinds #-}
3+{-# language DataKinds #-}
4+{-# language DefaultSignatures #-}
5+{-# language FlexibleContexts #-}
6+{-# language FlexibleInstances #-}
7+{-# language LambdaCase #-}
8+{-# language MultiParamTypeClasses #-}
9+{-# language PolyKinds #-}
10+{-# language QuantifiedConstraints #-}
11+{-# language ScopedTypeVariables #-}
12+{-# language StandaloneKindSignatures #-}
13+{-# language TypeApplications #-}
14+{-# language TypeFamilyDependencies #-}
15+{-# language TypeOperators #-}
16+{-# language UndecidableInstances #-}
17+
18+module Rel8.Generic.Rel8able
19+ ( KRel8able, Rel8able
20+ , Algebra
21+ , GRep
22+ , GColumns, gfromColumns, gtoColumns
23+ , GFromExprs, gfromResult, gtoResult
24+ , TSerialize, serialize, deserialize
25+ )
26+where
27+
28+-- base
29+import Data.Functor.Identity ( Identity )
30+import Data.Kind ( Constraint, Type )
31+import Data.Type.Bool ( type (&&) )
32+import GHC.Generics ( Generic, Rep, from, to )
33+import Prelude
34+
35+-- rel8
36+import Rel8.Aggregate ( Aggregate )
37+import Rel8.Expr ( Expr )
38+import Rel8.FCF ( Exp, Eval )
39+import Rel8.Generic.Record ( Record(..) )
40+import Rel8.Generic.Table ( GAlgebra )
41+import qualified Rel8.Generic.Table.Record as G
42+import qualified Rel8.Kind.Algebra as K ( Algebra(..) )
43+import Rel8.Kind.Context ( SContext(..) )
44+import Rel8.Schema.Field ( Field )
45+import Rel8.Schema.HTable ( HTable )
46+import qualified Rel8.Schema.Kind as K
47+import Rel8.Schema.Name ( Name )
48+import Rel8.Schema.Result ( Result )
49+import Rel8.Table
50+ ( Table, Columns, Context, fromColumns, toColumns
51+ , FromExprs, fromResult, toResult
52+ , Transpose
53+ , TTable, TColumns
54+ )
55+import Rel8.Table.Transpose ( Transposes )
56+
57+
58+-- | The kind of 'Rel8able' types
59+type KRel8able :: Type
60+type KRel8able = K.Rel8able
61+
62+
63+-- This is almost 'Data.Type.Equality.==', but we add an extra case.
64+type (==) :: k -> k -> Bool
65+type family a == b where
66+ -- This extra case is needed to solve the equation "a == a" (where a is a
67+ -- KRel8able), which occurs when we have polymorphic Rel8ables
68+ -- (e.g., newtype T t f = T { x :: t a })
69+ (a :: KRel8able) == (a :: KRel8able) = 'True
70+
71+ -- This extra case is needed to solve the equation "a == Identity a",
72+ -- which occurs when we have polymorphic Rel8ables
73+ -- (e.g., newtype T a f = T { x :: Column f a })
74+ a == Identity a = 'False
75+
76+ -- These cases are exactly the same as those in 'Data.Type.Equality.==.
77+ f a == g b = f == g && a == b
78+ a == a = 'True
79+ _ == _ = 'False
80+
81+
82+type Serialize :: Bool -> Type -> Type -> Constraint
83+class transposition ~ (a == Transpose Result expr) =>
84+ Serialize transposition expr a
85+ where
86+ serialize :: a -> Columns expr Result
87+ deserialize :: Columns expr Result -> a
88+
89+
90+instance
91+ ( (a == Transpose Result expr) ~ 'True
92+ , Transposes Expr Result expr a
93+ )
94+ => Serialize 'True expr a
95+ where
96+ serialize = toColumns
97+ deserialize = fromColumns
98+
99+
100+instance
101+ ( (a == Transpose Result expr) ~ 'False
102+ , Table (Context expr) expr
103+ , FromExprs expr ~ a
104+ )
105+ => Serialize 'False expr a
106+ where
107+ serialize = toResult @_ @expr
108+ deserialize = fromResult @_ @expr
109+
110+
111+data TSerialize :: Type -> Type -> Exp Constraint
112+type instance Eval (TSerialize expr a) =
113+ Serialize (a == Transpose Result expr) expr a
114+
115+
116+-- | This type class allows you to define custom 'Table's using higher-kinded
117+-- data types. Higher-kinded data types are data types of the pattern:
118+--
119+-- @
120+-- data MyType f =
121+-- MyType { field1 :: Column f T1 OR HK1 f
122+-- , field2 :: Column f T2 OR HK2 f
123+-- , ...
124+-- , fieldN :: Column f Tn OR HKn f
125+-- }
126+-- @
127+--
128+-- where @Tn@ is any Haskell type, and @HKn@ is any higher-kinded type.
129+--
130+-- That is, higher-kinded data are records where all fields in the record are
131+-- all either of the type @Column f T@ (for any @T@), or are themselves
132+-- higher-kinded data:
133+--
134+-- [Nested]
135+--
136+-- @
137+-- data Nested f =
138+-- Nested { nested1 :: MyType f
139+-- , nested2 :: MyType f
140+-- }
141+-- @
142+--
143+-- The @Rel8able@ type class is used to give us a special mapping operation
144+-- that lets us change the type parameter @f@.
145+--
146+-- [Supplying @Rel8able@ instances]
147+--
148+-- This type class should be derived generically for all table types in your
149+-- project. To do this, enable the @DeriveAnyClass@ and @DeriveGeneric@ language
150+-- extensions:
151+--
152+-- @
153+-- \{\-\# LANGUAGE DeriveAnyClass, DeriveGeneric #-\}
154+--
155+-- data MyType f = MyType { fieldA :: Column f T }
156+-- deriving ( GHC.Generics.Generic, Rel8able )
157+-- @
158+type Rel8able :: K.Rel8able -> Constraint
159+class HTable (GColumns t) => Rel8able t where
160+ type GColumns t :: K.HTable
161+ type GFromExprs t :: Type
162+
163+ gfromColumns :: SContext context -> GColumns t context -> t context
164+ gtoColumns :: SContext context -> t context -> GColumns t context
165+
166+ gfromResult :: GColumns t Result -> GFromExprs t
167+ gtoResult :: GFromExprs t -> GColumns t Result
168+
169+ type GColumns t = G.GColumns TColumns (GRep t Expr)
170+ type GFromExprs t = t Result
171+
172+ default gfromColumns :: forall context.
173+ ( SRel8able t Aggregate
174+ , SRel8able t Expr
175+ , forall table. SRel8able t (Field table)
176+ , SRel8able t Name
177+ , SSerialize t
178+ )
179+ => SContext context -> GColumns t context -> t context
180+ gfromColumns = \case
181+ SAggregate -> sfromColumns
182+ SExpr -> sfromColumns
183+ SField -> sfromColumns
184+ SName -> sfromColumns
185+ SResult -> sfromResult
186+
187+ default gtoColumns :: forall context.
188+ ( SRel8able t Aggregate
189+ , SRel8able t Expr
190+ , forall table. SRel8able t (Field table)
191+ , SRel8able t Name
192+ , SSerialize t
193+ )
194+ => SContext context -> t context -> GColumns t context
195+ gtoColumns = \case
196+ SAggregate -> stoColumns
197+ SExpr -> stoColumns
198+ SField -> stoColumns
199+ SName -> stoColumns
200+ SResult -> stoResult
201+
202+ default gfromResult :: (SSerialize t, GFromExprs t ~ t Result)
203+ => GColumns t Result -> GFromExprs t
204+ gfromResult = sfromResult
205+
206+ default gtoResult :: (SSerialize t, GFromExprs t ~ t Result)
207+ => GFromExprs t -> GColumns t Result
208+ gtoResult = stoResult
209+
210+
211+type Algebra :: K.Rel8able -> K.Algebra
212+type Algebra t = GAlgebra (GRep t Expr)
213+
214+
215+type GRep :: K.Rel8able -> K.Context -> Type -> Type
216+type GRep t context = Rep (Record (t context))
217+
218+
219+type SRel8able :: K.Rel8able -> K.Context -> Constraint
220+class
221+ ( Generic (Record (t context))
222+ , G.GTable (TTable context) TColumns (GRep t context)
223+ , G.GColumns TColumns (GRep t context) ~ GColumns t
224+ )
225+ => SRel8able t context
226+instance
227+ ( Generic (Record (t context))
228+ , G.GTable (TTable context) TColumns (GRep t context)
229+ , G.GColumns TColumns (GRep t context) ~ GColumns t
230+ )
231+ => SRel8able t context
232+
233+
234+type SSerialize :: K.Rel8able -> Constraint
235+type SSerialize t =
236+ ( Generic (Record (t Result))
237+ , G.GSerialize TSerialize TColumns (GRep t Expr) (GRep t Result)
238+ , G.GColumns TColumns (GRep t Expr) ~ GColumns t
239+ )
240+
241+
242+sfromColumns :: forall t context. SRel8able t context
243+ => GColumns t context -> t context
244+sfromColumns =
245+ unrecord .
246+ to .
247+ G.gfromColumns @(TTable context) @TColumns fromColumns
248+
249+
250+stoColumns :: forall t context. SRel8able t context
251+ => t context -> GColumns t context
252+stoColumns =
253+ G.gtoColumns @(TTable context) @TColumns toColumns .
254+ from .
255+ Record
256+
257+
258+sfromResult :: forall t. SSerialize t
259+ => GColumns t Result -> t Result
260+sfromResult =
261+ unrecord .
262+ to .
263+ G.gfromResult
264+ @TSerialize
265+ @TColumns
266+ @(GRep t Expr)
267+ @(GRep t Result)
268+ (\(_ :: proxy x) -> deserialize @_ @x)
269+
270+
271+stoResult :: forall t. SSerialize t
272+ => t Result -> GColumns t Result
273+stoResult =
274+ G.gtoResult
275+ @TSerialize
276+ @TColumns
277+ @(GRep t Expr)
278+ @(GRep t Result)
279+ (\(_ :: proxy x) -> serialize @_ @x) .
280+ from .
281+ Record
src/Rel8/Generic/Table.hs+72−96
@@ -1,8 +1,8 @@
11{-# language AllowAmbiguousTypes #-}
22{-# language DataKinds #-}
3+{-# language FlexibleContexts #-}
34{-# language FlexibleInstances #-}
45{-# language MultiParamTypeClasses #-}
5−{-# language PolyKinds #-}
66{-# language RankNTypes #-}
77{-# language ScopedTypeVariables #-}
88{-# language StandaloneKindSignatures #-}
@@ -12,116 +12,92 @@
1212{-# language UndecidableInstances #-}
1313
1414module Rel8.Generic.Table
15− ( GTable, GColumns, GContext, fromGColumns, toGColumns, gtable
15+ ( GGSerialize, GGColumns, ggfromResult, ggtoResult
16+ , GAlgebra
1617 )
1718where
1819
1920-- base
2021import Data.Kind ( Constraint, Type )
21−import Data.Proxy ( Proxy( Proxy ) )
22−import GHC.Generics
23− ( (:*:)( (:*:) ), K1( K1 ), M1( M1 )
24− , C, D, S
25− , Meta( MetaSel )
26− )
27−import GHC.TypeLits ( KnownSymbol )
28−import Prelude hiding ( null )
22+import GHC.Generics ( (:+:), (:*:), K1, M1, U1, V1 )
23+import Prelude ()
2924
3025-- rel8
3126import Rel8.FCF ( Eval, Exp )
32−import Rel8.Schema.Context.Label ( HLabelable, hlabeler, hunlabeler )
33−import Rel8.Schema.HTable ( HTable )
34−import Rel8.Schema.HTable.Label ( HLabel, hlabel, hunlabel )
35−import Rel8.Schema.HTable.Product ( HProduct(..) )
27+import Rel8.Generic.Table.ADT
28+ ( GSerializeADT, GColumnsADT, gtoResultADT, gfromResultADT
29+ )
30+import Rel8.Generic.Table.Record ( GSerialize, GColumns, gtoResult, gfromResult )
31+import Rel8.Kind.Algebra
32+ ( Algebra( Product, Sum )
33+ , SAlgebra( SProduct, SSum )
34+ , KnownAlgebra, algebraSing
35+ )
3636import qualified Rel8.Schema.Kind as K
37+import Rel8.Schema.Result ( Result )
3738
3839
39−type GColumns :: (Type -> Exp K.HTable) -> (Type -> Type) -> K.HTable
40−type family GColumns _Columns rep where
41− GColumns _Columns (M1 D _ rep) = GColumns _Columns rep
42− GColumns _Columns (M1 C _ rep) = GColumns _Columns rep
43− GColumns _Columns (rep1 :*: rep2) =
44− HProduct (GColumns _Columns rep1) (GColumns _Columns rep2)
45− GColumns _Columns (M1 S ('MetaSel ('Just label) _ _ _) (K1 _ a)) =
46− HLabel label (Eval (_Columns a))
40+data GGSerialize
41+ :: Algebra
42+ -> (Type -> Type -> Exp Constraint)
43+ -> (Type -> Exp K.HTable)
44+ -> (Type -> Type)
45+ -> (Type -> Type)
46+ -> Exp Constraint
4747
4848
49−type GContext :: (Type -> Exp a) -> (Type -> Type) -> a
50−type family GContext _Context rep where
51− GContext _Context (M1 _ _ rep) = GContext _Context rep
52− GContext _Context (rep1 :*: _rep2) = GContext _Context rep1
53− GContext _Context (K1 _ a) = Eval (_Context a)
49+type instance Eval (GGSerialize 'Product _Serialize _Columns exprs rep) =
50+ GSerialize _Serialize _Columns exprs rep
5451
5552
56−type GTable
57− :: (Type -> Exp Constraint)
53+type instance Eval (GGSerialize 'Sum _Serialize _Columns exprs rep) =
54+ GSerializeADT _Serialize _Columns exprs rep
55+
56+
57+data GGColumns
58+ :: Algebra
5859 -> (Type -> Exp K.HTable)
59− -> K.HContext -> (Type -> Type) -> Constraint
60−class GTable _Table _Columns context rep
61− where
62− fromGColumns :: ()
63− => (forall a. Eval (_Table a) => Eval (_Columns a) context -> a)
64− -> GColumns _Columns rep context
65− -> rep x
66−
67− toGColumns :: ()
68− => (forall a. Eval (_Table a) => a -> Eval (_Columns a) context)
69− -> rep x
70− -> GColumns _Columns rep context
71−
72− gtable :: ()
73− => (forall a. Eval (_Table a) => Proxy a -> Eval (_Columns a) context)
74− -> GColumns _Columns rep context
75−
76−
77−instance GTable _Table _Columns context rep =>
78− GTable _Table _Columns context (M1 D c rep)
79− where
80− fromGColumns fromColumns =
81− M1 . fromGColumns @_Table @_Columns @context @rep fromColumns
82− toGColumns toColumns (M1 a) =
83− toGColumns @_Table @_Columns @context @rep toColumns a
84− gtable = gtable @_Table @_Columns @context @rep
85−
86−
87−instance GTable _Table _Columns context rep =>
88− GTable _Table _Columns context (M1 C c rep)
89− where
90− fromGColumns fromColumns =
91− M1 . fromGColumns @_Table @_Columns @context @rep fromColumns
92− toGColumns toColumns (M1 a) =
93− toGColumns @_Table @_Columns @context @rep toColumns a
94− gtable = gtable @_Table @_Columns @context @rep
95−
96−
97−instance
98− ( GTable _Table _Columns context rep1
99− , GTable _Table _Columns context rep2
60+ -> (Type -> Type)
61+ -> Exp K.HTable
62+
63+
64+type instance Eval (GGColumns 'Product _Columns rep) = GColumns _Columns rep
65+
66+
67+type instance Eval (GGColumns 'Sum _Columns rep) = GColumnsADT _Columns rep
68+
69+
70+type GAlgebra :: (Type -> Type) -> Algebra
71+type family GAlgebra rep where
72+ GAlgebra (M1 _ _ rep) = GAlgebra rep
73+ GAlgebra V1 = 'Sum
74+ GAlgebra (_ :+: _) = 'Sum
75+ GAlgebra U1 = 'Sum
76+ GAlgebra (_ :*: _) = 'Product
77+ GAlgebra (K1 _ _) = 'Product
78+
79+
80+ggfromResult :: forall algebra _Serialize _Columns exprs rep x.
81+ ( KnownAlgebra algebra
82+ , Eval (GGSerialize algebra _Serialize _Columns exprs rep)
10083 )
101− => GTable _Table _Columns context (rep1 :*: rep2)
102− where
103− fromGColumns fromColumns (HProduct a b) =
104− fromGColumns @_Table @_Columns @context @rep1 fromColumns a :*:
105− fromGColumns @_Table @_Columns @context @rep2 fromColumns b
106− toGColumns toColumns (a :*: b) = HProduct
107− (toGColumns @_Table @_Columns @context @rep1 toColumns a)
108− (toGColumns @_Table @_Columns @context @rep2 toColumns b)
109− gtable table = HProduct
110− (gtable @_Table @_Columns @context @rep1 table)
111− (gtable @_Table @_Columns @context @rep2 table)
112−
113−
114−instance
115− ( HTable (Eval (_Columns a))
116− , Eval (_Table a)
117− , HLabelable context
118− , KnownSymbol label
119− , GColumns _Columns (M1 S meta k1) ~ HLabel label (Eval (_Columns a))
120− , meta ~ 'MetaSel ('Just label) _su _ss _ds
121− , k1 ~ K1 i a
84+ => (forall expr a proxy. Eval (_Serialize expr a)
85+ => proxy expr -> Eval (_Columns expr) Result -> a)
86+ -> Eval (GGColumns algebra _Columns exprs) Result
87+ -> rep x
88+ggfromResult f x = case algebraSing @algebra of
89+ SProduct -> gfromResult @_Serialize @_Columns @exprs @rep f x
90+ SSum -> gfromResultADT @_Serialize @_Columns @exprs @rep f x
91+
92+
93+ggtoResult :: forall algebra _Serialize _Columns exprs rep x.
94+ ( KnownAlgebra algebra
95+ , Eval (GGSerialize algebra _Serialize _Columns exprs rep)
12296 )
123− => GTable _Table _Columns context (M1 S meta k1)
124− where
125− fromGColumns fromColumns = M1 . K1 . fromColumns . hunlabel hunlabeler
126− toGColumns toColumns (M1 (K1 a)) = hlabel hlabeler (toColumns a)
127− gtable table = hlabel hlabeler (table (Proxy @a))
97+ => (forall expr a proxy. Eval (_Serialize expr a)
98+ => proxy expr -> a -> Eval (_Columns expr) Result)
99+ -> rep x
100+ -> Eval (GGColumns algebra _Columns exprs) Result
101+ggtoResult f x = case algebraSing @algebra of
102+ SProduct -> gtoResult @_Serialize @_Columns @exprs @rep f x
103+ SSum -> gtoResultADT @_Serialize @_Columns @exprs @rep f x
src/Rel8/Generic/Table/ADT.hsnew file+221
@@ -0,0 +1,221 @@
1+{-# language AllowAmbiguousTypes #-}
2+{-# language DataKinds #-}
3+{-# language FlexibleContexts #-}
4+{-# language FlexibleInstances #-}
5+{-# language LambdaCase #-}
6+{-# language MultiParamTypeClasses #-}
7+{-# language RankNTypes #-}
8+{-# language ScopedTypeVariables #-}
9+{-# language StandaloneKindSignatures #-}
10+{-# language TypeApplications #-}
11+{-# language TypeFamilies #-}
12+{-# language TypeOperators #-}
13+{-# language UndecidableInstances #-}
14+
15+module Rel8.Generic.Table.ADT
16+ ( GSerializeADT, GColumnsADT, gfromResultADT, gtoResultADT
17+ , GSerializeADT', GColumnsADT'
18+ )
19+where
20+
21+-- base
22+import Data.Functor.Identity ( Identity( Identity ) )
23+import Data.Kind ( Constraint, Type )
24+import Data.Proxy ( Proxy( Proxy ) )
25+import GHC.Generics
26+ ( (:+:)( L1, R1 ), M1( M1 ), U1( U1 )
27+ , C, D
28+ , Meta( MetaCons )
29+ )
30+import GHC.TypeLits ( KnownSymbol, symbolVal )
31+import Prelude hiding ( null )
32+
33+-- rel8
34+import Rel8.FCF ( Eval, Exp )
35+import Rel8.Generic.Table.Record ( GSerialize, GColumns, gfromResult, gtoResult )
36+import Rel8.Schema.HTable ( HTable )
37+import Rel8.Schema.HTable.Identity ( HIdentity( HIdentity ) )
38+import Rel8.Schema.HTable.Label ( HLabel, hlabel, hunlabel )
39+import Rel8.Schema.HTable.Nullify ( HNullify, hnulls, hnullify, hunnullify )
40+import Rel8.Schema.HTable.Product ( HProduct( HProduct ) )
41+import qualified Rel8.Schema.Kind as K
42+import Rel8.Schema.Result ( Result, null, nullifier, unnullifier )
43+import Rel8.Type.Tag ( Tag( Tag ) )
44+
45+-- text
46+import Data.Text ( pack )
47+
48+
49+type GColumnsADT
50+ :: (Type -> Exp K.HTable)
51+ -> (Type -> Type) -> K.HTable
52+type family GColumnsADT _Columns rep where
53+ GColumnsADT _Columns (M1 D _ rep) =
54+ GColumnsADT' _Columns (HLabel "tag" (HIdentity Tag)) rep
55+
56+
57+type GColumnsADT'
58+ :: (Type -> Exp K.HTable)
59+ -> K.HTable -> (Type -> Type) -> K.HTable
60+type family GColumnsADT' _Columns htable rep where
61+ GColumnsADT' _Columns htable (a :+: b) =
62+ GColumnsADT' _Columns (GColumnsADT' _Columns htable a) b
63+ GColumnsADT' _Columns htable (M1 C ('MetaCons _ _ _) U1) = htable
64+ GColumnsADT' _Columns htable (M1 C ('MetaCons label _ _) rep) =
65+ HProduct htable (HLabel label (HNullify (GColumns _Columns rep)))
66+
67+
68+type GSerializeADT
69+ :: (Type -> Type -> Exp Constraint)
70+ -> (Type -> Exp K.HTable)
71+ -> (Type -> Type) -> (Type -> Type) -> Constraint
72+class GSerializeADT _Serialize _Columns exprs rep where
73+ gfromResultADT :: ()
74+ => (forall expr a proxy. Eval (_Serialize expr a)
75+ => proxy expr -> Eval (_Columns expr) Result -> a)
76+ -> GColumnsADT _Columns exprs Result
77+ -> rep x
78+
79+ gtoResultADT :: ()
80+ => (forall expr a proxy. Eval (_Serialize expr a)
81+ => proxy expr -> a -> Eval (_Columns expr) Result)
82+ -> rep x
83+ -> GColumnsADT _Columns exprs Result
84+
85+
86+instance
87+ ( htable ~ HLabel "tag" (HIdentity Tag)
88+ , GSerializeADT' _Serialize _Columns htable exprs rep
89+ )
90+ => GSerializeADT _Serialize _Columns (M1 D meta exprs) (M1 D meta rep)
91+ where
92+ gfromResultADT fromResult columns =
93+ case gfromResultADT' @_Serialize @_Columns @htable @exprs @rep fromResult tag columns of
94+ Just rep -> M1 rep
95+ _ -> error "ADT.fromColumns: mismatch between tag and data"
96+ where
97+ tag = (\(HIdentity (Identity a)) -> a) . hunlabel @"tag"
98+
99+ gtoResultADT toResult (M1 rep) =
100+ gtoResultADT' @_Serialize @_Columns @htable @exprs @rep toResult tag (Just rep)
101+ where
102+ tag = hlabel @"tag" . HIdentity . Identity
103+
104+
105+type GSerializeADT'
106+ :: (Type -> Type -> Exp Constraint)
107+ -> (Type -> Exp K.HTable)
108+ -> K.HTable -> (Type -> Type) -> (Type -> Type) -> Constraint
109+class GSerializeADT' _Serialize _Columns htable exprs rep where
110+ gfromResultADT' :: context ~ Result
111+ => (forall expr a proxy. Eval (_Serialize expr a)
112+ => proxy expr -> Eval (_Columns expr) context -> a)
113+ -> (htable Result -> Tag)
114+ -> GColumnsADT' _Columns htable exprs context
115+ -> Maybe (rep x)
116+
117+ gtoResultADT' :: context ~ Result
118+ => (forall expr a proxy. Eval (_Serialize expr a)
119+ => proxy expr -> a -> Eval (_Columns expr) context)
120+ -> (Tag -> htable Result)
121+ -> Maybe (rep x)
122+ -> GColumnsADT' _Columns htable exprs context
123+
124+ extract :: GColumnsADT' _Columns htable exprs context -> htable context
125+
126+
127+instance
128+ ( htable' ~ GColumnsADT' _Columns htable exprs1
129+ , GSerializeADT' _Serialize _Columns htable exprs1 a
130+ , GSerializeADT' _Serialize _Columns htable' exprs2 b
131+ )
132+ => GSerializeADT' _Serialize _Columns htable (exprs1 :+: exprs2) (a :+: b)
133+ where
134+ gfromResultADT' fromResult f columns =
135+ case ma of
136+ Just a -> Just (L1 a)
137+ Nothing -> R1 <$>
138+ gfromResultADT' @_Serialize @_Columns @_ @exprs2 @b
139+ fromResult
140+ (f . extract @_Serialize @_Columns @_ @exprs1 @a)
141+ columns
142+ where
143+ ma =
144+ gfromResultADT' @_Serialize @_Columns @_ @exprs1 @a
145+ fromResult
146+ f
147+ (extract @_Serialize @_Columns @_ @exprs2 @b columns)
148+
149+ gtoResultADT' toResult tag = \case
150+ Just (L1 a) ->
151+ gtoResultADT' @_Serialize @_Columns @_ @exprs2 @b
152+ toResult
153+ (\_ -> gtoResultADT' @_Serialize @_Columns @_ @exprs1 @a
154+ toResult
155+ tag
156+ (Just a))
157+ Nothing
158+ Just (R1 b) ->
159+ gtoResultADT' @_Serialize @_Columns @_ @exprs2 @b
160+ toResult
161+ (\tag' ->
162+ gtoResultADT' @_Serialize @_Columns @_ @exprs1 @a
163+ toResult
164+ (\_ -> tag tag')
165+ Nothing)
166+ (Just b)
167+ Nothing ->
168+ gtoResultADT' @_Serialize @_Columns @_ @exprs2 @b
169+ toResult
170+ (\_ -> gtoResultADT' @_Serialize @_Columns @_ @exprs1 @a toResult tag Nothing)
171+ Nothing
172+
173+ extract =
174+ extract @_Serialize @_Columns @_ @exprs1 @a .
175+ extract @_Serialize @_Columns @_ @exprs2 @b
176+
177+
178+instance (meta ~ 'MetaCons label _fixity _isRecord, KnownSymbol label) =>
179+ GSerializeADT' _Serialize _Columns _htable (M1 C meta U1) (M1 C meta U1)
180+ where
181+ gfromResultADT' _ tag columns
182+ | tag columns == tag' = Just (M1 U1)
183+ | otherwise = Nothing
184+ where
185+ tag' = Tag $ pack $ symbolVal (Proxy @label)
186+
187+ gtoResultADT' _ tag _ = tag tag'
188+ where
189+ tag' = Tag $ pack $ symbolVal (Proxy @label)
190+
191+ extract = id
192+
193+
194+instance {-# OVERLAPPABLE #-}
195+ ( HTable (GColumns _Columns exprs)
196+ , GSerialize _Serialize _Columns exprs rep
197+ , meta ~ 'MetaCons label _fixity _isRecord
198+ , KnownSymbol label
199+ , GColumnsADT' _Columns htable (M1 C ('MetaCons label _fixity _isRecord) exprs) ~
200+ HProduct htable (HLabel label (HNullify (GColumns _Columns exprs)))
201+ )
202+ => GSerializeADT' _Serialize _Columns htable (M1 C meta exprs) (M1 C meta rep)
203+ where
204+ gfromResultADT' fromResult tag (HProduct a b)
205+ | tag a == tag' =
206+ M1 . gfromResult @_Serialize @_Columns @exprs @rep fromResult <$>
207+ hunnullify unnullifier (hunlabel b)
208+ | otherwise = Nothing
209+ where
210+ tag' = Tag $ pack $ symbolVal (Proxy @label)
211+
212+ gtoResultADT' toResult tag = \case
213+ Nothing -> HProduct (tag tag') (hlabel (hnulls (const null)))
214+ Just (M1 rep) -> HProduct (tag tag') $
215+ hlabel $
216+ hnullify nullifier $
217+ gtoResult @_Serialize @_Columns @exprs @rep toResult rep
218+ where
219+ tag' = Tag $ pack $ symbolVal (Proxy @label)
220+
221+ extract (HProduct a _) = a
src/Rel8/Generic/Table/Record.hsnew file+181
@@ -0,0 +1,181 @@
1+{-# language AllowAmbiguousTypes #-}
2+{-# language DataKinds #-}
3+{-# language FlexibleContexts #-}
4+{-# language FlexibleInstances #-}
5+{-# language MultiParamTypeClasses #-}
6+{-# language PolyKinds #-}
7+{-# language RankNTypes #-}
8+{-# language ScopedTypeVariables #-}
9+{-# language StandaloneKindSignatures #-}
10+{-# language TypeApplications #-}
11+{-# language TypeFamilies #-}
12+{-# language TypeOperators #-}
13+{-# language UndecidableInstances #-}
14+
15+module Rel8.Generic.Table.Record
16+ ( GTable, GColumns, GContext, gfromColumns, gtoColumns, gtable
17+ , GSerialize, gfromResult, gtoResult
18+ )
19+where
20+
21+-- base
22+import Data.Kind ( Constraint, Type )
23+import Data.Proxy ( Proxy( Proxy ) )
24+import GHC.Generics
25+ ( (:*:)( (:*:) ), K1( K1 ), M1( M1 )
26+ , C, D, S
27+ , Meta( MetaSel )
28+ )
29+import Prelude hiding ( null )
30+
31+-- rel8
32+import Rel8.FCF ( Eval, Exp )
33+import Rel8.Schema.HTable.Label ( HLabel, hlabel, hunlabel )
34+import Rel8.Schema.HTable.Product ( HProduct(..) )
35+import qualified Rel8.Schema.Kind as K
36+
37+
38+type GColumns :: (Type -> Exp K.HTable) -> (Type -> Type) -> K.HTable
39+type family GColumns _Columns rep where
40+ GColumns _Columns (M1 D _ rep) = GColumns _Columns rep
41+ GColumns _Columns (M1 C _ rep) = GColumns _Columns rep
42+ GColumns _Columns (rep1 :*: rep2) =
43+ HProduct (GColumns _Columns rep1) (GColumns _Columns rep2)
44+ GColumns _Columns (M1 S ('MetaSel ('Just label) _ _ _) (K1 _ a)) =
45+ HLabel label (Eval (_Columns a))
46+
47+
48+type GContext :: (Type -> Exp K.Context) -> (Type -> Type) -> K.Context
49+type family GContext _Context rep where
50+ GContext _Context (M1 _ _ rep) = GContext _Context rep
51+ GContext _Context (rep1 :*: _rep2) = GContext _Context rep1
52+ GContext _Context (K1 _ a) = Eval (_Context a)
53+
54+
55+type GTable
56+ :: (Type -> Exp Constraint)
57+ -> (Type -> Exp K.HTable)
58+ -> (Type -> Type) -> Constraint
59+class GTable _Table _Columns rep
60+ where
61+ gfromColumns :: ()
62+ => (forall a. Eval (_Table a) => Eval (_Columns a) context -> a)
63+ -> GColumns _Columns rep context
64+ -> rep x
65+
66+ gtoColumns :: ()
67+ => (forall a. Eval (_Table a) => a -> Eval (_Columns a) context)
68+ -> rep x
69+ -> GColumns _Columns rep context
70+
71+ gtable :: ()
72+ => (forall a proxy. Eval (_Table a) => proxy a -> Eval (_Columns a) context)
73+ -> GColumns _Columns rep context
74+
75+
76+type GSerialize
77+ :: (Type -> Type -> Exp Constraint)
78+ -> (Type -> Exp K.HTable)
79+ -> (Type -> Type) -> (Type -> Type) -> Constraint
80+class GSerialize _Serialize _Columns exprs rep
81+ where
82+ gfromResult :: ()
83+ => (forall expr a proxy. Eval (_Serialize expr a)
84+ => proxy expr -> Eval (_Columns expr) context -> a)
85+ -> GColumns _Columns exprs context
86+ -> rep x
87+
88+ gtoResult :: ()
89+ => (forall expr a proxy. Eval (_Serialize expr a)
90+ => proxy expr -> a -> Eval (_Columns expr) context)
91+ -> rep x
92+ -> GColumns _Columns exprs context
93+
94+
95+instance GTable _Table _Columns rep => GTable _Table _Columns (M1 D c rep)
96+ where
97+ gfromColumns fromColumns =
98+ M1 . gfromColumns @_Table @_Columns @rep fromColumns
99+ gtoColumns toColumns (M1 a) =
100+ gtoColumns @_Table @_Columns @rep toColumns a
101+ gtable = gtable @_Table @_Columns @rep
102+
103+
104+instance GSerialize _Serialize _Columns exprs rep =>
105+ GSerialize _Serialize _Columns (M1 D c exprs) (M1 D c rep)
106+ where
107+ gfromResult fromResult =
108+ M1 . gfromResult @_Serialize @_Columns @exprs @rep fromResult
109+ gtoResult toResult (M1 a) =
110+ gtoResult @_Serialize @_Columns @exprs @rep toResult a
111+
112+
113+instance GTable _Table _Columns rep => GTable _Table _Columns (M1 C c rep)
114+ where
115+ gfromColumns fromColumns =
116+ M1 . gfromColumns @_Table @_Columns @rep fromColumns
117+ gtoColumns toColumns (M1 a) =
118+ gtoColumns @_Table @_Columns @rep toColumns a
119+ gtable = gtable @_Table @_Columns @rep
120+
121+
122+instance GSerialize _Serialize _Columns exprs rep =>
123+ GSerialize _Serialize _Columns (M1 C c exprs) (M1 C c rep)
124+ where
125+ gfromResult fromResult =
126+ M1 . gfromResult @_Serialize @_Columns @exprs @rep fromResult
127+ gtoResult toResult (M1 a) =
128+ gtoResult @_Serialize @_Columns @exprs @rep toResult a
129+
130+
131+instance (GTable _Table _Columns rep1, GTable _Table _Columns rep2) =>
132+ GTable _Table _Columns (rep1 :*: rep2)
133+ where
134+ gfromColumns fromColumns (HProduct a b) =
135+ gfromColumns @_Table @_Columns @rep1 fromColumns a :*:
136+ gfromColumns @_Table @_Columns @rep2 fromColumns b
137+ gtoColumns toColumns (a :*: b) = HProduct
138+ (gtoColumns @_Table @_Columns @rep1 toColumns a)
139+ (gtoColumns @_Table @_Columns @rep2 toColumns b)
140+ gtable table = HProduct
141+ (gtable @_Table @_Columns @rep1 table)
142+ (gtable @_Table @_Columns @rep2 table)
143+
144+
145+instance
146+ ( GSerialize _Serialize _Columns expr1 rep1
147+ , GSerialize _Serialize _Columns expr2 rep2
148+ )
149+ => GSerialize _Serialize _Columns (expr1 :*: expr2) (rep1 :*: rep2)
150+ where
151+ gfromResult fromResult (HProduct a b) =
152+ gfromResult @_Serialize @_Columns @expr1 @rep1 fromResult a :*:
153+ gfromResult @_Serialize @_Columns @expr2 @rep2 fromResult b
154+ gtoResult toResult (a :*: b) =
155+ HProduct
156+ (gtoResult @_Serialize @_Columns @expr1 @rep1 toResult a)
157+ (gtoResult @_Serialize @_Columns @expr2 @rep2 toResult b)
158+
159+
160+instance
161+ ( Eval (_Table a)
162+ , meta ~ 'MetaSel ('Just label) _su _ss _ds
163+ , k1 ~ K1 i a
164+ )
165+ => GTable _Table _Columns (M1 S meta k1)
166+ where
167+ gfromColumns fromColumns = M1 . K1 . fromColumns . hunlabel
168+ gtoColumns toColumns (M1 (K1 a)) = hlabel (toColumns a)
169+ gtable table = hlabel (table (Proxy @a))
170+
171+
172+instance
173+ ( Eval (_Serialize expr a)
174+ , meta ~ 'MetaSel ('Just label) _su _ss _ds
175+ , k1 ~ K1 i expr
176+ , k1' ~ K1 i a
177+ )
178+ => GSerialize _Serialize _Columns (M1 S meta k1) (M1 S meta k1')
179+ where
180+ gfromResult fromResult = M1 . K1 . fromResult (Proxy @expr) . hunlabel
181+ gtoResult toResult (M1 (K1 a)) = hlabel (toResult (Proxy @expr) a)
src/Rel8/Kind/Algebra.hsnew file+38
@@ -0,0 +1,38 @@
1+{-# language DataKinds #-}
2+{-# language FlexibleContexts #-}
3+{-# language GADTs #-}
4+{-# language StandaloneKindSignatures #-}
5+
6+module Rel8.Kind.Algebra
7+ ( Algebra( Product, Sum )
8+ , SAlgebra( SProduct, SSum )
9+ , KnownAlgebra( algebraSing )
10+ )
11+where
12+
13+-- base
14+import Data.Kind ( Constraint, Type )
15+import Prelude ()
16+
17+
18+type Algebra :: Type
19+data Algebra = Product | Sum
20+
21+
22+type SAlgebra :: Algebra -> Type
23+data SAlgebra algebra where
24+ SProduct :: SAlgebra 'Product
25+ SSum :: SAlgebra 'Sum
26+
27+
28+type KnownAlgebra :: Algebra -> Constraint
29+class KnownAlgebra algebra where
30+ algebraSing :: SAlgebra algebra
31+
32+
33+instance KnownAlgebra 'Product where
34+ algebraSing = SProduct
35+
36+
37+instance KnownAlgebra 'Sum where
38+ algebraSing = SSum
src/Rel8/Kind/Context.hsnew file+56
@@ -0,0 +1,56 @@
1+{-# language DataKinds #-}
2+{-# language GADTs #-}
3+{-# language StandaloneKindSignatures #-}
4+{-# language TypeSynonymInstances #-}
5+
6+module Rel8.Kind.Context
7+ ( Reifiable( contextSing )
8+ , SContext(..)
9+ )
10+where
11+
12+-- base
13+import Data.Kind ( Constraint, Type )
14+import Prelude ()
15+
16+-- rel8
17+import Rel8.Aggregate ( Aggregate )
18+import Rel8.Expr ( Expr )
19+import Rel8.Schema.Field ( Field )
20+import Rel8.Schema.Kind ( Context )
21+import Rel8.Schema.Name ( Name )
22+import Rel8.Schema.Result ( Result )
23+
24+
25+type SContext :: Context -> Type
26+data SContext context where
27+ SAggregate :: SContext Aggregate
28+ SExpr :: SContext Expr
29+ SField :: SContext (Field table)
30+ SName :: SContext Name
31+ SResult :: SContext Result
32+
33+
34+type Reifiable :: Context -> Constraint
35+class Reifiable context where
36+ contextSing :: SContext context
37+
38+
39+instance Reifiable Aggregate where
40+ contextSing = SAggregate
41+
42+
43+instance Reifiable Expr where
44+ contextSing = SExpr
45+
46+
47+instance Reifiable (Field table) where
48+ contextSing = SField
49+
50+
51+instance Reifiable Result where
52+ contextSing = SResult
53+
54+
55+instance Reifiable Name where
56+ contextSing = SName
src/Rel8/Kind/Labels.hsdeleted−61
@@ -1,61 +0,0 @@
1−{-# language DataKinds #-}
2−{-# language FlexibleContexts #-}
3−{-# language FlexibleInstances #-}
4−{-# language GADTs #-}
5−{-# language LambdaCase #-}
6−{-# language StandaloneKindSignatures #-}
7−{-# language TypeOperators #-}
8−
9−module Rel8.Kind.Labels
10− ( Labels
11− , SLabels( SLabel, SLabels )
12− , KnownLabels( labelsSing )
13− , renderLabels
14− )
15−where
16−
17−-- base
18−import Data.Kind ( Constraint, Type )
19−import Data.List.NonEmpty ( NonEmpty( (:|) ), (<|) )
20−import Data.Proxy ( Proxy( Proxy ) )
21−import GHC.TypeLits ( KnownSymbol, Symbol, symbolVal )
22−import Prelude
23−
24−
25−type Labels :: Type
26−type Labels = [Symbol]
27−
28−
29−type SLabels :: Labels -> Type
30−data SLabels labels where
31− SLabel :: KnownSymbol label => Proxy label -> SLabels '[label]
32− SLabels :: KnownSymbol label => Proxy label -> SLabels labels -> SLabels (label ': labels)
33−
34−
35−type KnownLabels :: Labels -> Constraint
36−class KnownLabels labels where
37− labelsSing :: SLabels labels
38−
39−
40−instance KnownSymbol label => KnownLabels (label ': '[]) where
41− labelsSing = SLabel Proxy
42−
43−
44−instance (KnownSymbol label, KnownLabels (label_ ': labels)) =>
45− KnownLabels (label ': (label_ ': labels))
46− where
47− labelsSing = SLabels Proxy labelsSing
48−
49−
50−renderLabels :: SLabels labels -> NonEmpty String
51−renderLabels = cleanup . go
52− where
53− go :: SLabels labels -> NonEmpty String
54− go = \case
55− SLabel label -> pure (symbolVal label)
56− SLabels label labels -> symbolVal label <| go labels
57−
58− cleanup ("" :| []) = "anon" :| []
59− cleanup (a :| []) = a :| []
60− cleanup (a :| [""]) = a :| []
61− cleanup (a :| (b : c)) = a <| cleanup (b :| c)
src/Rel8/Kind/Necessity.hsdeleted−38
@@ -1,38 +0,0 @@
1−{-# language DataKinds #-}
2−{-# language FlexibleContexts #-}
3−{-# language GADTs #-}
4−{-# language StandaloneKindSignatures #-}
5−
6−module Rel8.Kind.Necessity
7− ( Necessity( Optional, Required )
8− , SNecessity( SOptional, SRequired )
9− , KnownNecessity( necessitySing )
10− )
11−where
12−
13−-- base
14−import Data.Kind ( Constraint, Type )
15−import Prelude ()
16−
17−
18−type Necessity :: Type
19−data Necessity = Optional | Required
20−
21−
22−type SNecessity :: Necessity -> Type
23−data SNecessity necessity where
24− SOptional :: SNecessity 'Optional
25− SRequired :: SNecessity 'Required
26−
27−
28−type KnownNecessity :: Necessity -> Constraint
29−class KnownNecessity necessity where
30− necessitySing :: SNecessity necessity
31−
32−
33−instance KnownNecessity 'Optional where
34− necessitySing = SOptional
35−
36−
37−instance KnownNecessity 'Required where
38− necessitySing = SRequired
src/Rel8/Order.hs+2−9
@@ -4,7 +4,6 @@
44
55module Rel8.Order
66 ( Order(..)
7− , toOrderExprs
87 )
98where
109
@@ -17,8 +16,7 @@ import Prelude
1716import Data.Functor.Contravariant.Divisible ( Decidable, Divisible )
1817
1918-- opaleye
20−import qualified Opaleye.Internal.HaskellDB.PrimQuery as Opaleye
21−import qualified Opaleye.Internal.Order as Opaleye
19+import qualified Opaleye.Order as Opaleye
2220
2321
2422-- | An ordering expression for @a@. Primitive orderings are defined with
@@ -26,12 +24,7 @@ import qualified Opaleye.Internal.Order as Opaleye
2624-- instances.
2725--
2826-- A common pattern is to use '<>' to combine multiple orderings in sequence,
29−-- and '>$<' (from 'Contravariant') to select individual columns.
27+-- and 'Data.Functor.Contravariant.>$<' to select individual columns.
3028type Order :: Type -> Type
3129newtype Order a = Order (Opaleye.Order a)
3230 deriving newtype (Contravariant, Divisible, Decidable, Semigroup, Monoid)
33−
34−
35−toOrderExprs :: Order a -> a -> [Opaleye.OrderExpr]
36−toOrderExprs (Order (Opaleye.Order order)) a =
37− uncurry Opaleye.OrderExpr <$> order a
src/Rel8/Query.hs+181−7
@@ -1,6 +1,6 @@
1−{-# language DerivingVia #-}
2−{-# language GeneralizedNewtypeDeriving #-}
1+{-# language FlexibleContexts #-}
32{-# language StandaloneKindSignatures #-}
3+{-# language UndecidableInstances #-}
44
55module Rel8.Query
66 ( Query( Query )
@@ -8,37 +8,201 @@ module Rel8.Query
88where
99
1010-- base
11+import Control.Applicative ( liftA2 )
12+import Control.Monad ( liftM2 )
1113import Data.Kind ( Type )
14+import Data.Monoid ( Any( Any ) )
1215import Prelude
1316
1417-- opaleye
15−import qualified Opaleye.Select as Opaleye
18+import qualified Opaleye.Internal.HaskellDB.PrimQuery as Opaleye
19+import qualified Opaleye.Internal.PackMap as Opaleye
20+import qualified Opaleye.Internal.PrimQuery as Opaleye hiding (lateral)
21+import qualified Opaleye.Internal.QueryArr as Opaleye
22+import qualified Opaleye.Internal.Tag as Opaleye
1623
1724-- rel8
25+import Rel8.Expr ( Expr )
1826import Rel8.Query.Set ( unionAll )
27+import Rel8.Query.Opaleye ( fromOpaleye )
1928import Rel8.Query.Values ( values )
29+import Rel8.Table ( Table, fromColumns, toColumns )
2030import Rel8.Table.Alternative
2131 ( AltTable, (<|>:)
2232 , AlternativeTable, emptyTable
2333 )
34+import Rel8.Table.Projection ( Projectable, apply, project )
2435
2536-- semigroupoids
26−import Data.Functor.Apply ( Apply, WrappedApplicative(..) )
37+import Data.Functor.Apply ( Apply, (<.>) )
2738import Data.Functor.Bind ( Bind, (>>-) )
2839
2940
3041-- | The @Query@ monad allows you to compose a @SELECT@ query. This monad has
3142-- semantics similar to the list (@[]@) monad.
3243type Query :: Type -> Type
33−newtype Query a = Query (Opaleye.Select a)
34− deriving newtype (Functor, Applicative, Monad)
35− deriving Apply via (WrappedApplicative Opaleye.Select)
44+newtype Query a =
45+ Query (
46+ -- This is based on Opaleye's Select monad, but with two addtions. We
47+ -- maintain a stack of PrimExprs from parent previous subselects. In
48+ -- practice, these are always the results of dummy calls to random().
49+ --
50+ -- We also return a Bool that indicates to the parent subselect whether
51+ -- or not that stack of PrimExprs were used at any point. If they weren't,
52+ -- then the call to random() is never added to the query.
53+ --
54+ -- This is all needed to implement evaluate. Consider the following code:
55+ --
56+ -- do
57+ -- x <- values [lit 'a', lit 'b', lit 'c']
58+ -- y <- evaluate $ nextval "user_id_seq"
59+ -- pure (x, y)
60+ --
61+ -- If we just used Opaleye's Select monad directly, the SQL would come out
62+ -- like this:
63+ --
64+ -- SELECT
65+ -- a, b
66+ -- FROM
67+ -- (VALUES ('a'), ('b'), ('c')) Q1(a),
68+ -- LATERAL (SELECT nextval('user_id_seq')) Q2(b);
69+ --
70+ -- From the Haskell code, you would intuitively expect to get back the
71+ -- results of three different calls to nextval(), but from Postgres' point
72+ -- of view, because the Q2 subquery doesn't reference anything from the Q1
73+ -- query, it thinks it only needs to call nextval() once. This is actually
74+ -- exactly the same problem you get with the deprecated ListT IO monad from
75+ -- the transformers package — *> behaves differently to >>=, so
76+ -- using ApplicativeDo can change the results of a program. ApplicativeDo
77+ -- is exactly the optimisation Postgres does on a "LATERAL" query that
78+ -- doesn't make any references to previous subselects.
79+ --
80+ -- Rel8's solution is generate the following SQL instead:
81+ --
82+ -- SELECT
83+ -- a, b
84+ -- FROM
85+ -- (SELECT
86+ -- random() AS dummy,
87+ -- *
88+ -- FROM
89+ -- (VALUES ('a'), ('b'), ('c')) Q1(a)) Q1,
90+ -- LATERAL (SELECT
91+ -- CASE
92+ -- WHEN dummy IS NOT NULL
93+ -- THEN nextval('user_id_seq')
94+ -- END) Q2(b);
95+ --
96+ -- We use random() here as the dummy value (and not some constant) because
97+ -- Postgres will again optimize if it sees that a value is constant
98+ -- (and thus only call nextval() once), but because random() is marked as
99+ -- VOLATILE, this inhibits Postgres from doing that optimisation.
100+ --
101+ -- Why not just reference the a column from the previous query directly
102+ -- instead of adding a dummy value? Basically, even if we extract out all
103+ -- the bindings introduced in a PrimQuery, we can't always be sure which
104+ -- ones refer to constant values, so if we end up laterally referencing a
105+ -- constant value, then all of this would be for nothing.
106+ --
107+ -- Why not just add the call to the previous subselect directly, like so:
108+ --
109+ -- SELECT
110+ -- a, b
111+ -- FROM
112+ -- (SELECT
113+ -- nextval('user_id_seq') AS eval,
114+ -- *
115+ -- FROM
116+ -- (VALUES ('a'), ('b'), ('c')) Q1(a)) Q1,
117+ -- LATERAL (SELECT eval) Q2(b);
118+ --
119+ -- That would work in this case. But consider the following Rel8 code:
120+ --
121+ -- do
122+ -- x <- values [lit 'a', lit 'b', lit 'c']
123+ -- y <- values [lit 'd', lit 'e', lit 'f']
124+ -- z <- evaluate $ nextval "user_id_seq"
125+ -- pure (x, y, z)
126+ --
127+ -- How many calls to nextval should there be? Our Haskell intuition says
128+ -- nine. But that's not what you would get if you used the above
129+ -- technique. The problem is, which VALUES query should the nextval be
130+ -- added to? You can choose one or the other to get three calls to
131+ -- nextval, but you still need to make a superfluous LATERAL references to
132+ -- the other if you want nine calls. So for the above Rel8 code we generate
133+ -- the following SQL:
134+ --
135+ -- SELECT
136+ -- a, b, c
137+ -- FROM
138+ -- (SELECT
139+ -- random() AS dummy,
140+ -- *
141+ -- FROM
142+ -- (VALUES ('a'), ('b'), ('c')) Q1(a)) Q1,
143+ -- (SELECT
144+ -- random() AS dummy,
145+ -- *
146+ -- FROM
147+ -- (VALUES ('d'), ('e'), ('f')) Q2(b)) Q2,
148+ -- LATERAL (SELECT
149+ -- CASE
150+ -- WHEN Q1.dummy IS NOT NULL AND Q2.dummy IS NOT NULL
151+ -- THEN nextval('user_id_seq')
152+ -- END) Q3(c);
153+ --
154+ -- This gives nine calls to nextval() as we would expect.
155+ [Opaleye.PrimExpr] -> Opaleye.Select (Any, a)
156+ )
157+
158+
159+instance Projectable Query where
160+ project f = fmap (fromColumns . apply f . toColumns)
161+
162+
163+instance Functor Query where
164+ fmap f (Query a) = Query (fmap (fmap (fmap f)) a)
165+
166+
167+instance Apply Query where
168+ (<.>) = (<*>)
169+
170+
171+instance Applicative Query where
172+ pure = fromOpaleye . pure
173+ liftA2 = liftM2
36174
37175
38176instance Bind Query where
39177 (>>-) = (>>=)
40178
41179
180+instance Monad Query where
181+ Query q >>= f = Query $ \dummies -> Opaleye.stateQueryArr $ \_ tag ->
182+ let
183+ qa = q dummies
184+ ((m, a), query, tag') = Opaleye.runStateQueryArr qa () tag
185+ Query q' = f a
186+ (dummies', query', tag'') =
187+ ( dummy : dummies
188+ , query <> Opaleye.aRebind bindings
189+ , Opaleye.next tag'
190+ )
191+ where
192+ (dummy, bindings) = Opaleye.run $ name random
193+ where
194+ random = Opaleye.FunExpr "random" []
195+ name = Opaleye.extractAttr "dummy" tag'
196+ qa' = Opaleye.lateral $ \_ -> q' dummies'
197+ ((m'@(Any needsDummies), b), query'', tag''') = Opaleye.runStateQueryArr qa' () tag''
198+ query'''
199+ | needsDummies = query' <> query''
200+ | otherwise = query <> query''
201+ m'' = m <> m'
202+ in
203+ ((m'', b), query''', tag''')
204+
205+
42206-- | '<|>:' = 'unionAll'.
43207instance AltTable Query where
44208 (<|>:) = unionAll
@@ -47,3 +211,13 @@ instance AltTable Query where
47211-- | 'emptyTable' = 'values' @[]@.
48212instance AlternativeTable Query where
49213 emptyTable = values []
214+
215+
216+-- | '<>' = 'unionAll'.
217+instance Table Expr a => Semigroup (Query a) where
218+ (<>) = (<|>:)
219+
220+
221+-- | 'mempty' = @'values' []@.
222+instance Table Expr a => Monoid (Query a) where
223+ mempty = emptyTable
src/Rel8/Query.hs-boot+3−1
@@ -7,11 +7,13 @@ where
77
88-- base
99import Data.Kind ( Type )
10+import Data.Monoid ( Any )
1011import Prelude ()
1112
1213-- opaleye
14+import qualified Opaleye.Internal.HaskellDB.PrimQuery as Opaleye
1315import qualified Opaleye.Select as Opaleye
1416
1517
1618type Query :: Type -> Type
17−newtype Query a = Query (Opaleye.Select a)
19+newtype Query a = Query ([Opaleye.PrimExpr] -> Opaleye.Select (Any, a))
src/Rel8/Query/Aggregate.hs+22−2
@@ -1,12 +1,17 @@
11{-# language FlexibleContexts #-}
2+{-# language MonoLocalBinds #-}
3+{-# language ScopedTypeVariables #-}
4+{-# language TypeApplications #-}
25
36module Rel8.Query.Aggregate
47 ( aggregate
58 , countRows
9+ , mode
610 )
711where
812
913-- base
14+import Data.Functor.Contravariant ( (>$<) )
1015import Data.Int ( Int64 )
1116import Prelude
1217
@@ -14,18 +19,25 @@ import Prelude
1419import qualified Opaleye.Aggregate as Opaleye
1520
1621-- rel8
17−import Rel8.Aggregate ( Aggregate )
22+import Rel8.Aggregate ( Aggregates )
1823import Rel8.Expr ( Expr )
1924import Rel8.Expr.Aggregate ( countStar )
25+import Rel8.Expr.Order ( desc )
2026import Rel8.Query ( Query )
27+import Rel8.Query.Limit ( limit )
2128import Rel8.Query.Maybe ( optional )
2229import Rel8.Query.Opaleye ( mapOpaleye )
30+import Rel8.Query.Order ( orderBy )
31+import Rel8.Table ( toColumns )
32+import Rel8.Table.Aggregate ( hgroupBy )
33+import Rel8.Table.Cols ( Cols( Cols ), fromCols )
34+import Rel8.Table.Eq ( EqTable, eqTable )
2335import Rel8.Table.Opaleye ( aggregator )
2436import Rel8.Table.Maybe ( maybeTable )
2537
2638
2739-- | Apply an aggregation to all rows returned by a 'Query'.
28−aggregate :: Query (Aggregate exprs) -> Query exprs
40+aggregate :: Aggregates aggregates exprs => Query aggregates -> Query exprs
2941aggregate = mapOpaleye (Opaleye.aggregate aggregator)
3042
3143
@@ -34,3 +46,11 @@ aggregate = mapOpaleye (Opaleye.aggregate aggregator)
3446-- will return @0@.
3547countRows :: Query a -> Query (Expr Int64)
3648countRows = fmap (maybeTable 0 id) . optional . aggregate . fmap (const countStar)
49+
50+
51+-- | Return the most common row in a query.
52+mode :: forall a. EqTable a => Query a -> Query a
53+mode rows = limit 1 $ fmap (fromCols . snd) $ orderBy (fst >$< desc) $ do
54+ aggregate $ do
55+ row <- toColumns <$> rows
56+ pure (countStar, Cols $ hgroupBy (eqTable @a) row)
src/Rel8/Query/Distinct.hs+4−9
@@ -1,5 +1,3 @@
1−{-# options_ghc -fno-warn-redundant-constraints #-}
2−
31module Rel8.Query.Distinct
42 ( distinct
53 , distinctOn
@@ -8,12 +6,11 @@ module Rel8.Query.Distinct
86where
97
108-- base
11−import Prelude
9+import Prelude ()
1210
1311-- opaleye
1412import qualified Opaleye.Distinct as Opaleye
15−import qualified Opaleye.Internal.Order as Opaleye
16−import qualified Opaleye.Internal.QueryArr as Opaleye
13+import qualified Opaleye.Order as Opaleye
1714
1815-- rel8
1916import Rel8.Order ( Order( Order ) )
@@ -33,13 +30,11 @@ distinct = mapOpaleye (Opaleye.distinctExplicit distinctspec)
3330-- to a projection. If multiple rows have the same projection, it is
3431-- unspecified which row will be returned. If this matters, use 'distinctOnBy'.
3532distinctOn :: EqTable b => (a -> b) -> Query a -> Query a
36−distinctOn proj =
37− mapOpaleye (\q -> Opaleye.productQueryArr (Opaleye.distinctOn unpackspec proj . Opaleye.runSimpleQueryArr q))
33+distinctOn proj = mapOpaleye (Opaleye.distinctOnExplicit unpackspec proj)
3834
3935
4036-- | Select all distinct rows from a query, where rows are equivalent according
4137-- to a projection. If there are multiple rows with the same projection, the
4238-- first row according to the specified 'Order' will be returned.
4339distinctOnBy :: EqTable b => (a -> b) -> Order a -> Query a -> Query a
44−distinctOnBy proj (Order order) =
45− mapOpaleye (\q -> Opaleye.productQueryArr (Opaleye.distinctOnBy unpackspec proj order . Opaleye.runSimpleQueryArr q))
40+distinctOnBy proj (Order order) = mapOpaleye (Opaleye.distinctOnByExplicit unpackspec proj order)
src/Rel8/Query/Each.hs+3−3
@@ -17,7 +17,7 @@ import Rel8.Query ( Query )
1717import Rel8.Query.Opaleye ( fromOpaleye )
1818import Rel8.Schema.Name ( Selects )
1919import Rel8.Schema.Table ( TableSchema )
20−import Rel8.Table ( fromColumns, toColumns )
20+import Rel8.Table.Cols ( fromCols, toCols )
2121import Rel8.Table.Opaleye ( table, unpackspec )
2222
2323
@@ -25,8 +25,8 @@ import Rel8.Table.Opaleye ( table, unpackspec )
2525-- table@.
2626each :: Selects names exprs => TableSchema names -> Query exprs
2727each =
28− fmap fromColumns .
28+ fmap fromCols .
2929 fromOpaleye .
3030 Opaleye.selectTableExplicit unpackspec .
3131 table .
32− fmap toColumns
32+ fmap toCols
src/Rel8/Query/Either.hs+27−17
@@ -3,23 +3,22 @@
33module Rel8.Query.Either
44 ( keepLeftTable
55 , keepRightTable
6− , bindEitherTable
76 , bitraverseEitherTable
87 )
98where
109
1110-- base
12−import Data.Functor ( (<&>) )
1311import Prelude
1412
13+-- comonad
14+import Control.Comonad ( extract )
15+
1516-- rel8
1617import Rel8.Expr ( Expr )
1718import Rel8.Expr.Eq ( (==.) )
1819import Rel8.Query ( Query )
1920import Rel8.Query.Filter ( where_ )
2021import Rel8.Query.Maybe ( optional )
21−import Rel8.Table ( Table )
22−import Rel8.Table.Bool ( bool )
2322import Rel8.Table.Either
2423 ( EitherTable( EitherTable )
2524 , isLeftTable, isRightTable
@@ -27,30 +26,41 @@ import Rel8.Table.Either
2726import Rel8.Table.Maybe ( MaybeTable( MaybeTable ), isJustTable )
2827
2928
30−keepLeftTable :: EitherTable a b -> Query a
29+-- | Filter 'EitherTable's, keeping only 'leftTable's.
30+keepLeftTable :: EitherTable Expr a b -> Query a
3131keepLeftTable e@(EitherTable _ a _) = do
3232 where_ $ isLeftTable e
33− pure a
33+ pure (extract a)
3434
3535
36−keepRightTable :: EitherTable a b -> Query b
36+-- | Filter 'EitherTable's, keeping only 'rightTable's.
37+keepRightTable :: EitherTable Expr a b -> Query b
3738keepRightTable e@(EitherTable _ _ b) = do
3839 where_ $ isRightTable e
39− pure b
40−
41−
42−bindEitherTable :: (Table Expr a, Functor m)
43− => (i -> m (EitherTable a b)) -> EitherTable a i -> m (EitherTable a b)
44−bindEitherTable query e@(EitherTable input a i) = do
45− query i <&> \(EitherTable output a' b) ->
46− EitherTable (input <> output) (bool a a' (isRightTable e)) b
40+ pure (extract b)
4741
4842
43+-- | @bitraverseEitherTable f g x@ will pass all @leftTable@s through @f@ and
44+-- all @rightTable@s through @g@. The results are then lifted back into
45+-- @leftTable@ and @rightTable@, respectively. This is similar to 'bitraverse'
46+-- for 'Either'.
47+--
48+-- For example,
49+--
50+-- >>> :{
51+-- select do
52+-- x <- values (map lit [ Left True, Right (42 :: Int32) ])
53+-- bitraverseEitherTable (\y -> values [y, not_ y]) (\y -> pure (y * 100)) x
54+-- :}
55+-- [ Left True
56+-- , Left False
57+-- , Right 4200
58+-- ]
4959bitraverseEitherTable :: ()
5060 => (a -> Query c)
5161 -> (b -> Query d)
52− -> EitherTable a b
53− -> Query (EitherTable c d)
62+ -> EitherTable Expr a b
63+ -> Query (EitherTable Expr c d)
5464bitraverseEitherTable f g e@(EitherTable tag _ _) = do
5565 mc@(MaybeTable _ c) <- optional (f =<< keepLeftTable e)
5666 md@(MaybeTable _ d) <- optional (g =<< keepRightTable e)
src/Rel8/Query/Evaluate.hsnew file+49
@@ -0,0 +1,49 @@
1+{-# language FlexibleContexts #-}
2+{-# language TupleSections #-}
3+
4+module Rel8.Query.Evaluate
5+ ( evaluate
6+ )
7+where
8+
9+-- base
10+import Control.Monad ( (>=>) )
11+import Data.Foldable ( foldl' )
12+import Data.List.NonEmpty ( NonEmpty( (:|) ), nonEmpty )
13+import Data.Monoid ( Any( Any ) )
14+import Prelude hiding ( undefined )
15+
16+-- opaleye
17+import qualified Opaleye.Internal.HaskellDB.PrimQuery as Opaleye
18+
19+-- rel8
20+import Rel8.Expr ( Expr )
21+import Rel8.Expr.Bool ( (&&.) )
22+import Rel8.Expr.Opaleye ( fromPrimExpr )
23+import Rel8.Query ( Query( Query ) )
24+import Rel8.Query.Rebind ( rebind )
25+import Rel8.Table ( Table )
26+import Rel8.Table.Bool ( case_ )
27+import Rel8.Table.Undefined ( undefined )
28+
29+
30+-- | 'evaluate' takes expressions that could potentially have side effects and
31+-- \"runs\" them in the 'Query' monad. The returned expressions have no side
32+-- effects and can safely be reused.
33+evaluate :: Table Expr a => a -> Query a
34+evaluate = laterally >=> rebind "eval"
35+
36+
37+laterally :: Table Expr a => a -> Query a
38+laterally a = Query $ \bindings -> pure $ (Any True,) $
39+ case nonEmpty bindings of
40+ Nothing -> a
41+ Just bindings' -> case_ [(condition, a)] undefined
42+ where
43+ condition = foldl1' (&&.) (fmap go bindings')
44+ where
45+ go = fromPrimExpr . Opaleye.UnExpr Opaleye.OpIsNotNull
46+
47+
48+foldl1' :: (a -> a -> a) -> NonEmpty a -> a
49+foldl1' f (a :| as) = foldl' f a as
src/Rel8/Query/Exists.hs+15−17
@@ -2,8 +2,8 @@
22
33module Rel8.Query.Exists
44 ( exists, inQuery
5− , whereExists, with, withBy
6− , whereNotExists, without, withoutBy
5+ , present, with, withBy
6+ , absent, without, withoutBy
77 )
88where
99
@@ -11,56 +11,54 @@ where
1111import Prelude hiding ( filter )
1212
1313-- opaleye
14+import qualified Opaleye.Exists as Opaleye
1415import qualified Opaleye.Operators as Opaleye
1516
1617-- rel8
1718import Rel8.Expr ( Expr )
19+import Rel8.Expr.Opaleye ( fromColumn, fromPrimExpr )
1820import Rel8.Query ( Query )
1921import Rel8.Query.Filter ( filter )
20−import Rel8.Query.Maybe ( optional )
2122import Rel8.Query.Opaleye ( mapOpaleye )
2223import Rel8.Table.Eq ( EqTable, (==:) )
23−import Rel8.Table.Maybe ( isJustTable )
2424
2525
2626-- | Checks if a query returns at least one row.
2727exists :: Query a -> Query (Expr Bool)
28−exists = fmap isJustTable . optional . whereExists
29−-- FIXME: change this when b7aacc07c6392654cae439fc3b997620c3aa7a87 makes it
30−-- into a release of Opaleye
28+exists = fmap (fromPrimExpr . fromColumn) . mapOpaleye Opaleye.exists
3129
3230
3331inQuery :: EqTable a => a -> Query a -> Query (Expr Bool)
3432inQuery a = exists . (>>= filter (a ==:))
3533
3634
37−-- | Produce the empty query if the given query returns no rows. @whereExists@
35+-- | Produce the empty query if the given query returns no rows. @present@
3836-- is equivalent to @WHERE EXISTS@ in SQL.
39−whereExists :: Query a -> Query ()
40−whereExists = mapOpaleye Opaleye.restrictExists
37+present :: Query a -> Query ()
38+present = mapOpaleye Opaleye.restrictExists
4139
4240
43−-- | Produce the empty query if the given query returns rows. @whereNotExists@
41+-- | Produce the empty query if the given query returns rows. @absent@
4442-- is equivalent to @WHERE NOT EXISTS@ in SQL.
45−whereNotExists :: Query a -> Query ()
46−whereNotExists = mapOpaleye Opaleye.restrictNotExists
43+absent :: Query a -> Query ()
44+absent = mapOpaleye Opaleye.restrictNotExists
4745
4846
4947-- | @with@ is similar to 'filter', but allows the predicate to be a full query.
5048--
51−-- @with f a = a <$ whereExists (f a)@, but this form matches 'filter'.
49+-- @with f a = a <$ present (f a)@, but this form matches 'filter'.
5250with :: (a -> Query b) -> a -> Query a
53−with f a = a <$ whereExists (f a)
51+with f a = a <$ present (f a)
5452
5553
5654-- | Like @with@, but with a custom membership test.
57−withBy :: (a -> b -> Expr Bool) -> Query b -> a -> Query a
55+withBy :: (a -> b -> Expr Bool) -> Query b -> a -> Query a
5856withBy predicate bs = with $ \a -> bs >>= filter (predicate a)
5957
6058
6159-- | Filter rows where @a -> Query b@ yields no rows.
6260without :: (a -> Query b) -> a -> Query a
63−without f a = a <$ whereNotExists (f a)
61+without f a = a <$ absent (f a)
6462
6563
6664-- | Like @without@, but with a custom membership test.
src/Rel8/Query/Indexed.hsnew file+21
@@ -0,0 +1,21 @@
1+module Rel8.Query.Indexed
2+ ( indexed
3+ )
4+where
5+
6+-- base
7+import Control.Applicative ( liftA2 )
8+import Data.Int ( Int64 )
9+import Prelude
10+
11+-- rel8
12+import Rel8.Expr ( Expr )
13+import Rel8.Expr.Window ( rowNumber )
14+import Rel8.Query ( Query )
15+import Rel8.Query.Window ( window )
16+import Rel8.Table.Window ( currentRow )
17+
18+
19+-- | Pair each row of a query with its index within the query.
20+indexed :: Query a -> Query (Expr Int64, a)
21+indexed = window (liftA2 (,) (subtract 1 <$> rowNumber) currentRow)
src/Rel8/Query/List.hs+93−14
@@ -1,23 +1,58 @@
11{-# language FlexibleContexts #-}
2+{-# language GADTs #-}
3+{-# language NamedFieldPuns #-}
24
35module Rel8.Query.List
46 ( many, some
7+ , manyExpr, someExpr
8+ , catListTable, catNonEmptyTable
9+ , catList, catNonEmpty
510 )
611where
712
813-- base
14+import Data.Functor.Identity ( runIdentity )
15+import Data.List.NonEmpty ( NonEmpty )
916import Prelude
1017
18+-- opaleye
19+import qualified Opaleye.Internal.HaskellDB.PrimQuery as Opaleye
20+
1121-- rel8
1222import Rel8.Expr ( Expr )
23+import Rel8.Expr.Aggregate ( listAggExpr, nonEmptyAggExpr )
24+import Rel8.Expr.Opaleye ( mapPrimExpr )
1325import Rel8.Query ( Query )
1426import Rel8.Query.Aggregate ( aggregate )
1527import Rel8.Query.Maybe ( optional )
16−import Rel8.Table ( Table )
28+import Rel8.Query.Rebind ( rebind )
29+import Rel8.Schema.HTable.Vectorize ( hunvectorize )
30+import Rel8.Schema.Null ( Sql, Unnullify )
31+import Rel8.Schema.Spec ( Spec( Spec, info ) )
32+import Rel8.Table ( Table, fromColumns )
33+import Rel8.Table.Cols ( toCols )
1734import Rel8.Table.Aggregate ( listAgg, nonEmptyAgg )
18−import Rel8.Table.List ( ListTable )
35+import Rel8.Table.List ( ListTable( ListTable ) )
1936import Rel8.Table.Maybe ( maybeTable )
20−import Rel8.Table.NonEmpty ( NonEmptyTable )
37+import Rel8.Table.NonEmpty ( NonEmptyTable( NonEmptyTable ) )
38+import Rel8.Type ( DBType, typeInformation )
39+import Rel8.Type.Array ( extractArrayElement )
40+import Rel8.Type.Information ( TypeInformation )
41+
42+
43+-- | Aggregate a 'Query' into a 'ListTable'. If the supplied query returns 0
44+-- rows, this function will produce a 'Query' that returns one row containing
45+-- the empty @ListTable@. If the supplied @Query@ does return rows, @many@ will
46+-- return exactly one row, with a @ListTable@ collecting all returned rows.
47+--
48+-- @many@ is analogous to 'Control.Applicative.many' from
49+-- @Control.Applicative@.
50+many :: Table Expr a => Query a -> Query (ListTable Expr a)
51+many =
52+ fmap (maybeTable mempty (\(ListTable a) -> ListTable a)) .
53+ optional .
54+ aggregate .
55+ fmap (listAgg . toCols)
2156
2257
2358-- | Aggregate a 'Query' into a 'NonEmptyTable'. If the supplied query returns
@@ -28,16 +63,60 @@ import Rel8.Table.NonEmpty ( NonEmptyTable )
2863--
2964-- @some@ is analogous to 'Control.Applicative.some' from
3065-- @Control.Applicative@.
31−some :: Table Expr a => Query a -> Query (NonEmptyTable a)
32−some = aggregate . fmap nonEmptyAgg
66+some :: Table Expr a => Query a -> Query (NonEmptyTable Expr a)
67+some =
68+ fmap (\(NonEmptyTable a) -> NonEmptyTable a) .
69+ aggregate .
70+ fmap (nonEmptyAgg . toCols)
3371
3472
35−-- | Aggregate a 'Query' into a 'ListTable'. If the supplied query returns 0
36−-- rows, this function will produce a 'Query' that returns one row containing
37−-- the empty @ListTable@. If the supplied @Query@ does return rows, @many@ will
38−-- return exactly one row, with a @ListTable@ collecting all returned rows.
39−--
40−-- @many@ is analogous to 'Control.Applicative.many' from
41−-- @Control.Applicative@.
42−many :: Table Expr a => Query a -> Query (ListTable a)
43−many = fmap (maybeTable mempty id) . optional . aggregate . fmap listAgg
73+-- | A version of 'many' specialised to single expressions.
74+manyExpr :: Sql DBType a => Query (Expr a) -> Query (Expr [a])
75+manyExpr = fmap (maybeTable mempty id) . optional . aggregate . fmap listAggExpr
76+
77+
78+-- | A version of 'many' specialised to single expressions.
79+someExpr :: Sql DBType a => Query (Expr a) -> Query (Expr (NonEmpty a))
80+someExpr = aggregate . fmap nonEmptyAggExpr
81+
82+
83+-- | Expand a 'ListTable' into a 'Query', where each row in the query is an
84+-- element of the given @ListTable@.
85+--
86+-- @catListTable@ is an inverse to 'many'.
87+catListTable :: Table Expr a => ListTable Expr a -> Query a
88+catListTable (ListTable as) =
89+ rebind "unnest" $ fromColumns $ runIdentity $
90+ hunvectorize (\Spec {info} -> pure . sunnest info) as
91+
92+
93+-- | Expand a 'NonEmptyTable' into a 'Query', where each row in the query is an
94+-- element of the given @NonEmptyTable@.
95+--
96+-- @catNonEmptyTable@ is an inverse to 'some'.
97+catNonEmptyTable :: Table Expr a => NonEmptyTable Expr a -> Query a
98+catNonEmptyTable (NonEmptyTable as) =
99+ rebind "unnest" $ fromColumns $ runIdentity $
100+ hunvectorize (\Spec {info} -> pure . sunnest info) as
101+
102+
103+-- | Expand an expression that contains a list into a 'Query', where each row
104+-- in the query is an element of the given list.
105+--
106+-- @catList@ is an inverse to 'manyExpr'.
107+catList :: Sql DBType a => Expr [a] -> Query (Expr a)
108+catList = rebind "unnest" . sunnest typeInformation
109+
110+
111+-- | Expand an expression that contains a non-empty list into a 'Query', where
112+-- each row in the query is an element of the given list.
113+--
114+-- @catNonEmpty@ is an inverse to 'someExpr'.
115+catNonEmpty :: Sql DBType a => Expr (NonEmpty a) -> Query (Expr a)
116+catNonEmpty = rebind "unnest" . sunnest typeInformation
117+
118+
119+sunnest :: TypeInformation (Unnullify a) -> Expr (list a) -> Expr a
120+sunnest info = mapPrimExpr $
121+ extractArrayElement info .
122+ Opaleye.UnExpr (Opaleye.UnOpOther "UNNEST")
src/Rel8/Query/Maybe.hs+26−45
@@ -1,7 +1,10 @@
1+{-# language GADTs #-}
2+{-# language LambdaCase #-}
3+{-# language NamedFieldPuns #-}
4+
15module Rel8.Query.Maybe
26 ( optional
37 , catMaybeTable
4− , bindMaybeTable
58 , traverseMaybeTable
69 )
710where
@@ -9,23 +12,20 @@ where
912-- base
1013import Prelude
1114
15+-- comonad
16+import Control.Comonad ( extract )
17+
1218-- opaleye
13−import qualified Opaleye.Internal.PackMap as Opaleye
14−import qualified Opaleye.Internal.PrimQuery as Opaleye
15−import qualified Opaleye.Internal.QueryArr as Opaleye
16−import qualified Opaleye.Internal.Tag as Opaleye
17−import qualified Opaleye.Internal.Unpackspec as Opaleye
19+import qualified Opaleye.Internal.MaybeFields as Opaleye
1820
1921-- rel8
20−import Rel8.Expr.Bool ( true )
22+import Rel8.Expr ( Expr )
2123import Rel8.Expr.Eq ( (==.) )
22−import Rel8.Expr.Opaleye ( toPrimExpr )
24+import Rel8.Expr.Opaleye ( fromColumn, fromPrimExpr )
2325import Rel8.Query ( Query )
2426import Rel8.Query.Filter ( where_ )
2527import Rel8.Query.Opaleye ( mapOpaleye )
26−import Rel8.Table.Maybe ( MaybeTable( MaybeTable ), isJustTable )
27−import Rel8.Table.Opaleye ( unpackspec )
28−import Rel8.Table.Tag ( Tag(..), fromExpr )
28+import Rel8.Table.Maybe ( MaybeTable(..), isJustTable )
2929
3030
3131-- | Convert a query that might return zero rows to a query that always returns
@@ -33,18 +33,11 @@ import Rel8.Table.Tag ( Tag(..), fromExpr )
3333--
3434-- To speak in more concrete terms, 'optional' is most useful to write @LEFT
3535-- JOIN@s.
36−optional :: Query a -> Query (MaybeTable a)
37−optional = mapOpaleye $ Opaleye.QueryArr . go
38− where
39− go query (i, left, tag) =
40− (MaybeTable (fromExpr t') a, join, Opaleye.next tag')
41− where
42− (MaybeTable Tag {expr = t} a, right, tag') =
43− Opaleye.runSimpleQueryArr (pure <$> query) (i, tag)
44− (t', bindings) = Opaleye.run $
45− Opaleye.runUnpackspec unpackspec (Opaleye.extractAttr "maybe" tag') t
46− join = Opaleye.Join Opaleye.LeftJoin condition [] bindings left right
47− condition = toPrimExpr true
36+optional :: Query a -> Query (MaybeTable Expr a)
37+optional = mapOpaleye $ Opaleye.optionalInternal $ \tag a -> MaybeTable
38+ { tag = fromPrimExpr $ fromColumn tag
39+ , just = pure a
40+ }
4841
4942
5043-- | Filter out 'MaybeTable's, returning only the tables that are not-null.
@@ -52,36 +45,24 @@ optional = mapOpaleye $ Opaleye.QueryArr . go
5245-- This operation can be used to "undo" the effect of 'optional', which
5346-- operationally is like turning a @LEFT JOIN@ back into a full @JOIN@. You
5447-- can think of this as analogous to 'Data.Maybe.catMaybes'.
55−catMaybeTable :: MaybeTable a -> Query a
48+catMaybeTable :: MaybeTable Expr a -> Query a
5649catMaybeTable ma@(MaybeTable _ a) = do
5750 where_ $ isJustTable ma
58− pure a
59−
60−
61−-- | @bindMaybeTable f x@ is similar to the monadic bind (@>>=@) operation. It
62−-- allows you to "extend" an optional query with another query. If either the
63−-- input or output are 'Rel8.nothingTable', then the result is
64−-- 'Rel8.nothingTable'.
65−--
66−-- This is similar to 'traverseMaybeTable', followed by a @join@ on the
67−-- resulting @MaybeTable@s.
68−bindMaybeTable :: Monad m
69− => (a -> m (MaybeTable b)) -> MaybeTable a -> m (MaybeTable b)
70−bindMaybeTable query (MaybeTable input a) = do
71− MaybeTable output b <- query a
72− pure $ MaybeTable (input <> output) b
51+ pure (extract a)
7352
7453
7554-- | Extend an optional query with another query. This is useful if you want
7655-- to step through multiple @LEFT JOINs@.
7756--
7857-- Note that @traverseMaybeTable@ takes a @a -> Query b@ function, which means
79−-- you also have the ability to "expand" one row into multiple rows. If the
58+-- you also have the ability to "expand" one row into multiple rows. If the
8059-- @a -> Query b@ function returns no rows, then the resulting query will also
8160-- have no rows. However, regardless of the given @a -> Query b@ function, if
82−-- the input is @noTable@, you will always get exactly one @noTable@ back.
83−traverseMaybeTable :: (a -> Query b) -> MaybeTable a -> Query (MaybeTable b)
61+-- the input is @nothingTable@, you will always get exactly one @nothingTable@
62+-- back.
63+traverseMaybeTable :: (a -> Query b) -> MaybeTable Expr a -> Query (MaybeTable Expr b)
8464traverseMaybeTable query ma@(MaybeTable input _) = do
85− MaybeTable output b <- optional (query =<< catMaybeTable ma)
86− where_ $ expr output ==. expr input
87− pure $ MaybeTable input b
65+ optional (query =<< catMaybeTable ma) >>= \case
66+ MaybeTable output b -> do
67+ where_ $ output ==. input
68+ pure $ MaybeTable input b
src/Rel8/Query/Null.hs+15
@@ -1,5 +1,8 @@
1+{-# language FlexibleContexts #-}
2+
13module Rel8.Query.Null
24 ( catNull
5+ , catNullTable
36 )
47where
58
@@ -9,6 +12,8 @@ import Prelude
912-- rel8
1013import Rel8.Expr ( Expr )
1114import Rel8.Expr.Null ( isNonNull, unsafeUnnullify )
15+import Rel8.Table ( Table )
16+import Rel8.Table.Null ( NullTable, isNonNullTable, unsafeUnnullifyTable )
1217import Rel8.Query ( Query )
1318import Rel8.Query.Filter ( where_ )
1419
@@ -21,3 +26,13 @@ catNull :: Expr (Maybe a) -> Query (Expr a)
2126catNull a = do
2227 where_ $ isNonNull a
2328 pure $ unsafeUnnullify a
29+
30+
31+-- | Filter a 'Query' that might return @nullTable@ to a 'Query' without any
32+-- @nullTable@s.
33+--
34+-- Corresponds to 'Data.Maybe.catMaybes'.
35+catNullTable :: Table Expr a => NullTable Expr a -> Query a
36+catNullTable a = do
37+ where_ $ isNonNullTable a
38+ pure $ unsafeUnnullifyTable a
src/Rel8/Query/Opaleye.hs+41−5
@@ -1,34 +1,70 @@
1+{-# language TupleSections #-}
2+
13module Rel8.Query.Opaleye
24 ( fromOpaleye
35 , toOpaleye
46 , mapOpaleye
57 , zipOpaleyeWith
8+ , unsafePeekQuery
69 )
710where
811
912-- base
13+import Control.Applicative ( liftA2 )
1014import Prelude
1115
1216-- opaleye
13−import qualified Opaleye.Select as Opaleye
17+import qualified Opaleye.Internal.QueryArr as Opaleye
18+import qualified Opaleye.Internal.Tag as Opaleye
1419
1520-- rel8
1621import {-# SOURCE #-} Rel8.Query ( Query( Query ) )
1722
1823
1924fromOpaleye :: Opaleye.Select a -> Query a
20−fromOpaleye = Query
25+fromOpaleye = Query . pure . fmap pure
2126
2227
2328toOpaleye :: Query a -> Opaleye.Select a
24−toOpaleye (Query a) = a
29+toOpaleye (Query a) = snd <$> a mempty
2530
2631
2732mapOpaleye :: (Opaleye.Select a -> Opaleye.Select b) -> Query a -> Query b
28−mapOpaleye f = fromOpaleye . f . toOpaleye
33+mapOpaleye f (Query a) = Query (fmap (mapping f) a)
2934
3035
3136zipOpaleyeWith :: ()
3237 => (Opaleye.Select a -> Opaleye.Select b -> Opaleye.Select c)
3338 -> Query a -> Query b -> Query c
34−zipOpaleyeWith f a b = fromOpaleye $ f (toOpaleye a) (toOpaleye b)
39+zipOpaleyeWith f (Query a) (Query b) = Query $ liftA2 (zipping f) a b
40+
41+
42+unsafePeekQuery :: Query a -> a
43+unsafePeekQuery (Query q) = case q mempty of
44+ f -> case Opaleye.runStateQueryArr f () Opaleye.start of
45+ ((_, a), _, _) -> a
46+
47+
48+mapping :: ()
49+ => (Opaleye.Select a -> Opaleye.Select b)
50+ -> Opaleye.Select (m, a) -> Opaleye.Select (m, b)
51+mapping f q = Opaleye.stateQueryArr $ \_ tag ->
52+ let
53+ ((m, _), _, _) = Opaleye.runStateQueryArr q () tag
54+ q' = (m,) <$> f (snd <$> q)
55+ in
56+ Opaleye.runStateQueryArr q' () tag
57+
58+
59+zipping :: Semigroup m
60+ => (Opaleye.Select a -> Opaleye.Select b -> Opaleye.Select c)
61+ -> Opaleye.Select (m, a) -> Opaleye.Select (m, b) -> Opaleye.Select (m, c)
62+zipping f q q' =
63+ Opaleye.stateQueryArr $ \_ tag ->
64+ let
65+ ((m, _), _, _) = Opaleye.runStateQueryArr q () tag
66+ ((m', _), _, _) = Opaleye.runStateQueryArr q' () tag
67+ m'' = m <> m'
68+ q'' = (m'',) <$> f (snd <$> q) (snd <$> q')
69+ in
70+ Opaleye.runStateQueryArr q'' () tag
src/Rel8/Query/Rebind.hsnew file+27
@@ -0,0 +1,27 @@
1+{-# language FlexibleContexts #-}
2+
3+module Rel8.Query.Rebind
4+ ( rebind
5+ )
6+where
7+
8+-- base
9+import Prelude
10+import Control.Arrow ((<<<))
11+
12+-- opaleye
13+import qualified Opaleye.Internal.Rebind as Opaleye
14+
15+-- rel8
16+import Rel8.Expr ( Expr )
17+import Rel8.Query ( Query )
18+import Rel8.Table ( Table )
19+import Rel8.Table.Opaleye ( unpackspec )
20+import Rel8.Query.Opaleye (fromOpaleye)
21+
22+
23+-- | 'rebind' takes a variable name, some expressions, and binds each of them
24+-- to a new variable in the SQL. The @a@ returned consists only of these
25+-- variables. It's essentially a @let@ binding for Postgres expressions.
26+rebind :: Table Expr a => String -> a -> Query a
27+rebind prefix a = fromOpaleye (Opaleye.rebindExplicitPrefix prefix unpackspec <<< pure a)
src/Rel8/Query/SQL.hs+6−59
@@ -1,74 +1,21 @@
11{-# language FlexibleContexts #-}
2−{-# language TypeFamilies #-}
3−{-# language ViewPatterns #-}
2+{-# language MonoLocalBinds #-}
43
54module Rel8.Query.SQL
65 ( showQuery
7− , sqlForQuery, sqlForQueryWithNames
86 )
97where
108
119-- base
12−import Data.Foldable ( fold )
13−import Data.Functor.Const ( Const( Const ), getConst )
14−import Data.Void ( Void )
1510import Prelude
1611
17−-- opaleye
18−import qualified Opaleye.Internal.HaskellDB.Sql as Opaleye
19−import qualified Opaleye.Internal.PrimQuery as Opaleye
20−import qualified Opaleye.Internal.Print as Opaleye
21−import qualified Opaleye.Internal.Optimize as Opaleye
22−import qualified Opaleye.Internal.QueryArr as Opaleye hiding ( Select )
23−import qualified Opaleye.Internal.Sql as Opaleye
24−
2512-- rel8
26−import Rel8.Expr ( Expr, Col(..) )
27−import Rel8.Expr.Opaleye ( toPrimExpr )
13+import Rel8.Expr ( Expr )
2814import Rel8.Query ( Query )
29−import Rel8.Query.Opaleye ( toOpaleye )
30−import Rel8.Schema.Name ( Selects, Col(..) )
31−import Rel8.Schema.HTable ( htabulateA, hfield )
32−import Rel8.Table ( Table, toColumns )
33−import Rel8.Table.Name ( namesFromLabels )
34−import Rel8.Table.Opaleye ( castTable )
15+import Rel8.Statement.Select ( ppSelect )
16+import Rel8.Table ( Table )
3517
3618
37−-- | Convert a query to a 'String' containing the query as a @SELECT@
38−-- statement.
19+-- | Convert a 'Query' to a 'String' containing a @SELECT@ statement.
3920showQuery :: Table Expr a => Query a -> String
40−showQuery = fold . sqlForQuery
41−
42−
43−sqlForQuery :: Table Expr a
44− => Query a -> Maybe String
45−sqlForQuery = sqlForQueryWithNames namesFromLabels . fmap toColumns
46−
47−
48−sqlForQueryWithNames :: Selects names exprs
49− => names -> Query exprs -> Maybe String
50−sqlForQueryWithNames names query =
51− show . Opaleye.ppSql . selectFrom names exprs <$> optimize primQuery
52− where
53− (exprs, primQuery, _) =
54− Opaleye.runSimpleQueryArrStart (toOpaleye query) ()
55−
56−
57−optimize :: Opaleye.PrimQuery' a -> Maybe (Opaleye.PrimQuery' Void)
58−optimize = Opaleye.removeEmpty . Opaleye.optimize
59−
60−
61−selectFrom :: Selects names exprs
62− => names -> exprs -> Opaleye.PrimQuery' Void -> Opaleye.Select
63−selectFrom (toColumns -> names) (toColumns . castTable -> exprs) query =
64− Opaleye.SelectFrom $ Opaleye.newSelect
65− { Opaleye.attrs = Opaleye.SelectAttrs attributes
66− , Opaleye.tables = Opaleye.oneTable select
67− }
68− where
69− select = Opaleye.foldPrimQuery Opaleye.sqlQueryGenerator query
70− attributes = getConst $ htabulateA $ \field -> case hfield names field of
71− NameCol name -> case hfield exprs field of
72− DB (toPrimExpr -> expr) -> Const (pure (makeAttr name expr))
73− makeAttr label expr =
74− (Opaleye.sqlExpr expr, Just (Opaleye.SqlColumn label))
21+showQuery = show . ppSelect
src/Rel8/Query/Set.hs+6−6
@@ -23,36 +23,36 @@ import Rel8.Table.Opaleye ( binaryspec )
2323
2424
2525-- | Combine the results of two queries of the same type, collapsing
26−-- duplicates. @union a b@ is the same as the SQL statement @x UNION b@.
26+-- duplicates. @union a b@ is the same as the SQL statement @a UNION b@.
2727union :: EqTable a => Query a -> Query a -> Query a
2828union = zipOpaleyeWith (Opaleye.unionExplicit binaryspec)
2929
3030
3131-- | Combine the results of two queries of the same type, retaining duplicates.
32−-- @unionAll a b@ is the same as the SQL statement @x UNION ALL b@.
32+-- @unionAll a b@ is the same as the SQL statement @a UNION ALL b@.
3333unionAll :: Table Expr a => Query a -> Query a -> Query a
3434unionAll = zipOpaleyeWith (Opaleye.unionAllExplicit binaryspec)
3535
3636
3737-- | Find the intersection of two queries, collapsing duplicates. @intersect a
38−-- b@ is the same as the SQL statement @x INTERSECT b@.
38+-- b@ is the same as the SQL statement @a INTERSECT b@.
3939intersect :: EqTable a => Query a -> Query a -> Query a
4040intersect = zipOpaleyeWith (Opaleye.intersectExplicit binaryspec)
4141
4242
4343-- | Find the intersection of two queries, retaining duplicates. @intersectAll
44−-- a b@ is the same as the SQL statement @x INTERSECT ALL b@.
44+-- a b@ is the same as the SQL statement @a INTERSECT ALL b@.
4545intersectAll :: EqTable a => Query a -> Query a -> Query a
4646intersectAll = zipOpaleyeWith (Opaleye.intersectAllExplicit binaryspec)
4747
4848
4949-- | Find the difference of two queries, collapsing duplicates @except a b@ is
50−-- the same as the SQL statement @x INTERSECT b@.
50+-- the same as the SQL statement @a EXCEPT b@.
5151except :: EqTable a => Query a -> Query a -> Query a
5252except = zipOpaleyeWith (Opaleye.exceptExplicit binaryspec)
5353
5454
5555-- | Find the difference of two queries, retaining duplicates. @exceptAll a b@
56−-- is the same as the SQL statement @x EXCEPT ALL b@.
56+-- is the same as the SQL statement @a EXCEPT ALL b@.
5757exceptAll :: EqTable a => Query a -> Query a -> Query a
5858exceptAll = zipOpaleyeWith (Opaleye.exceptAllExplicit binaryspec)
src/Rel8/Query/These.hs+52−45
@@ -1,4 +1,5 @@
11{-# language FlexibleContexts #-}
2+{-# language GADTs #-}
23
34module Rel8.Query.These
45 ( alignBy
@@ -7,7 +8,6 @@ module Rel8.Query.These
78 , keepThisTable, loseThisTable
89 , keepThatTable, loseThatTable
910 , keepThoseTable, loseThoseTable
10− , bindTheseTable
1111 , bitraverseTheseTable
1212 )
1313where
@@ -15,27 +15,29 @@ where
1515-- base
1616import Prelude
1717
18+-- comonad
19+import Control.Comonad ( extract )
20+
1821-- opaleye
19−import qualified Opaleye.Internal.Join as Opaleye
22+import qualified Opaleye.Internal.PackMap as Opaleye
2023import qualified Opaleye.Internal.PrimQuery as Opaleye
24+import qualified Opaleye.Internal.QueryArr as Opaleye
25+import qualified Opaleye.Internal.Tag as Opaleye
2126
2227-- rel8
2328import Rel8.Expr ( Expr )
2429import Rel8.Expr.Bool ( boolExpr, not_ )
2530import Rel8.Expr.Eq ( (==.) )
26−import Rel8.Expr.Opaleye ( toColumn, toPrimExpr )
31+import Rel8.Expr.Opaleye ( toPrimExpr, traversePrimExpr )
2732import Rel8.Expr.Serialize ( litExpr )
2833import Rel8.Query ( Query )
2934import Rel8.Query.Filter ( where_ )
3035import Rel8.Query.Maybe ( optional )
3136import Rel8.Query.Opaleye ( zipOpaleyeWith )
32−import Rel8.Table ( Table )
3337import Rel8.Table.Either ( EitherTable( EitherTable ) )
3438import Rel8.Table.Maybe ( MaybeTable( MaybeTable ), isJustTable )
35−import Rel8.Table.Opaleye ( unpackspec )
36−import Rel8.Table.Tag ( Tag(..) )
3739import Rel8.Table.These
38− ( TheseTable( TheseTable )
40+ ( TheseTable( TheseTable, here, there )
3941 , hasHereTable, hasThereTable
4042 , isThisTable, isThatTable, isThoseTable
4143 )
@@ -43,86 +45,91 @@ import Rel8.Type.Tag ( EitherTag( IsLeft, IsRight ) )
4345
4446
4547-- | Corresponds to a @FULL OUTER JOIN@ between two queries.
46−alignBy :: (Table Expr a, Table Expr b)
48+alignBy :: ()
4749 => (a -> b -> Expr Bool)
48− -> Query a -> Query b -> Query (TheseTable a b)
49−alignBy condition as bs =
50− uncurry TheseTable <$> zipOpaleyeWith fullOuterJoin as bs
51− where
52− fullOuterJoin a b =
53− Opaleye.joinExplicit unpackspec unpackspec pure pure full a b on
54− where
55− full = Opaleye.FullJoin
56− on = toColumn . toPrimExpr . uncurry condition
57−
58−
59−keepHereTable :: TheseTable a b -> Query (a, MaybeTable b)
50+ -> Query a -> Query b -> Query (TheseTable Expr a b)
51+alignBy condition = zipOpaleyeWith $ \left right -> Opaleye.stateQueryArr $ \_ t -> case t of
52+ tag -> (tab, join', tag''')
53+ where
54+ (ma, left', tag') = Opaleye.runStateQueryArr (pure <$> left) () tag
55+ (mb, right', tag'') = Opaleye.runStateQueryArr (pure <$> right) () tag'
56+ MaybeTable hasHere a = ma
57+ MaybeTable hasThere b = mb
58+ (hasHere', lbindings) = Opaleye.run $ do
59+ traversePrimExpr (Opaleye.extractAttr "hasHere" tag'') hasHere
60+ (hasThere', rbindings) = Opaleye.run $ do
61+ traversePrimExpr (Opaleye.extractAttr "hasThere" tag'') hasThere
62+ tag''' = Opaleye.next tag''
63+ join = Opaleye.Join Opaleye.FullJoin on left'' right''
64+ where
65+ on = toPrimExpr $ condition (extract a) (extract b)
66+ left'' = (Opaleye.NonLateral, Opaleye.toPrimQuery (left' <> Opaleye.aRebind lbindings))
67+ right'' = (Opaleye.NonLateral, Opaleye.toPrimQuery (right' <> Opaleye.aRebind rbindings))
68+ ma' = MaybeTable hasHere' a
69+ mb' = MaybeTable hasThere' b
70+ tab = TheseTable {here = ma', there = mb'}
71+ join' = Opaleye.aProduct join
72+
73+
74+keepHereTable :: TheseTable Expr a b -> Query (a, MaybeTable Expr b)
6075keepHereTable = loseThatTable
6176
6277
63−loseHereTable :: TheseTable a b -> Query b
78+loseHereTable :: TheseTable Expr a b -> Query b
6479loseHereTable = keepThatTable
6580
6681
67−keepThereTable :: TheseTable a b -> Query (MaybeTable a, b)
82+keepThereTable :: TheseTable Expr a b -> Query (MaybeTable Expr a, b)
6883keepThereTable = loseThisTable
6984
7085
71−loseThereTable :: TheseTable a b -> Query a
86+loseThereTable :: TheseTable Expr a b -> Query a
7287loseThereTable = keepThisTable
7388
7489
75−keepThisTable :: TheseTable a b -> Query a
90+keepThisTable :: TheseTable Expr a b -> Query a
7691keepThisTable t@(TheseTable (MaybeTable _ a) _) = do
7792 where_ $ isThisTable t
78− pure a
93+ pure (extract a)
7994
8095
81−loseThisTable :: TheseTable a b -> Query (MaybeTable a, b)
96+loseThisTable :: TheseTable Expr a b -> Query (MaybeTable Expr a, b)
8297loseThisTable t@(TheseTable ma (MaybeTable _ b)) = do
8398 where_ $ not_ $ isThisTable t
84− pure (ma, b)
99+ pure (ma, extract b)
85100
86101
87−keepThatTable :: TheseTable a b -> Query b
102+keepThatTable :: TheseTable Expr a b -> Query b
88103keepThatTable t@(TheseTable _ (MaybeTable _ b)) = do
89104 where_ $ isThatTable t
90− pure b
105+ pure (extract b)
91106
92107
93−loseThatTable :: TheseTable a b -> Query (a, MaybeTable b)
108+loseThatTable :: TheseTable Expr a b -> Query (a, MaybeTable Expr b)
94109loseThatTable t@(TheseTable (MaybeTable _ a) mb) = do
95110 where_ $ not_ $ isThatTable t
96− pure (a, mb)
111+ pure (extract a, mb)
97112
98113
99−keepThoseTable :: TheseTable a b -> Query (a, b)
114+keepThoseTable :: TheseTable Expr a b -> Query (a, b)
100115keepThoseTable t@(TheseTable (MaybeTable _ a) (MaybeTable _ b)) = do
101116 where_ $ isThoseTable t
102− pure (a, b)
117+ pure (extract a, extract b)
103118
104119
105−loseThoseTable :: TheseTable a b -> Query (EitherTable a b)
120+loseThoseTable :: TheseTable Expr a b -> Query (EitherTable Expr a b)
106121loseThoseTable t@(TheseTable (MaybeTable _ a) (MaybeTable _ b)) = do
107122 where_ $ not_ $ isThoseTable t
108− pure $ EitherTable result a b
123+ pure $ EitherTable tag a b
109124 where
110125 tag = boolExpr (litExpr IsLeft) (litExpr IsRight) (isThatTable t)
111− result = (mempty `asTypeOf` result) {expr = tag}
112−
113−
114−bindTheseTable :: (Table Expr a, Semigroup a, Monad m)
115− => (i -> m (TheseTable a b)) -> TheseTable a i -> m (TheseTable a b)
116−bindTheseTable query (TheseTable here (MaybeTable input i)) = do
117− TheseTable here' (MaybeTable output b) <- query i
118− pure $ TheseTable (here <> here') (MaybeTable (input <> output) b)
119126
120127
121128bitraverseTheseTable :: ()
122129 => (a -> Query c)
123130 -> (b -> Query d)
124− -> TheseTable a b
125− -> Query (TheseTable c d)
131+ -> TheseTable Expr a b
132+ -> Query (TheseTable Expr c d)
126133bitraverseTheseTable f g t = do
127134 mc <- optional (f . fst =<< keepHereTable t)
128135 md <- optional (g . snd =<< keepThereTable t)
src/Rel8/Query/Window.hsnew file+26
@@ -0,0 +1,26 @@
1+module Rel8.Query.Window
2+ ( window
3+ )
4+where
5+
6+-- base
7+import Prelude ()
8+
9+-- opaleye
10+import qualified Opaleye.Window as Opaleye
11+
12+-- rel8
13+import Rel8.Query ( Query )
14+import Rel8.Query.Opaleye ( mapOpaleye )
15+import Rel8.Window ( Window( Window ) )
16+
17+
18+-- | 'window' runs a query composed of expressions containing
19+-- [window functions](https://www.postgresql.org/docs/current/tutorial-window.html).
20+-- 'window' is similar to 'Rel8.aggregate', with the main difference being
21+-- that in a window query, each input row corresponds to one output row,
22+-- whereas aggregation queries fold the entire input query down into a single
23+-- row. To put this into a Haskell context, 'Rel8.aggregate' is to 'foldl' as
24+-- 'window' is to 'scanl'.
25+window :: Window a b -> Query a -> Query b
26+window (Window a) = mapOpaleye (Opaleye.runWindows a)
src/Rel8/Schema/Column.hsdeleted−29
@@ -1,29 +0,0 @@
1−{-# language DataKinds #-}
2−{-# language TypeFamilies #-}
3−{-# language StandaloneKindSignatures #-}
4−
5−module Rel8.Schema.Column
6− ( Column, Default
7− )
8−where
9−
10−-- base
11−import Data.Kind ( Type )
12−import Prelude ()
13−
14−-- rel8
15−import Rel8.Kind.Necessity ( Necessity( Required, Optional ) )
16−import Rel8.Schema.Field ( Field )
17−import qualified Rel8.Schema.Kind as K
18−
19−
20−-- | The @Column@ type family should be used to indicate which fields of your
21−-- data types are single columns in queries. This type family has special
22−-- support when a query is executed, allowing you to use a single data type for
23−-- both query data and rows decoded to Haskell.
24−type Column :: K.Context -> Type -> Type
25−type Column context a = Field context 'Required a
26−
27−
28−type Default :: K.Context -> Type -> Type
29−type Default context a = Field context 'Optional a
src/Rel8/Schema/Context.hsdeleted−28
@@ -1,28 +0,0 @@
1−{-# language DataKinds #-}
2−{-# language GADTs #-}
3−{-# language StandaloneKindSignatures #-}
4−{-# language TypeFamilies #-}
5−
6−module Rel8.Schema.Context
7− ( Interpretation(..), Col( Result )
8− )
9−where
10−
11−-- base
12−import Data.Kind ( Constraint )
13−import Prelude ()
14−
15−-- rel8
16−import Rel8.Schema.Kind ( Context, HContext )
17−import Rel8.Schema.Result ( Result )
18−import Rel8.Schema.Spec ( Spec( Spec ) )
19−
20−
21−type Interpretation :: Context -> Constraint
22−class Interpretation context where
23− data Col context :: HContext
24−
25−
26−instance Interpretation Result where
27− data Col Result _spec where
28− Result :: a -> Col Result ('Spec labels necessity a)
src/Rel8/Schema/Context/Label.hsdeleted−60
@@ -1,60 +0,0 @@
1−{-# language DataKinds #-}
2−{-# language FlexibleInstances #-}
3−{-# language StandaloneKindSignatures #-}
4−{-# language TypeFamilies #-}
5−{-# language TypeOperators #-}
6−
7−module Rel8.Schema.Context.Label
8− ( Labelable( labeler, unlabeler )
9− , HLabelable( hlabeler, hunlabeler )
10− )
11−where
12−
13−-- base
14−import Data.Kind ( Constraint )
15−import Prelude hiding ( null )
16−
17−-- rel8
18−import Rel8.Schema.Context ( Interpretation, Col(..) )
19−import Rel8.Schema.Dict ( Dict( Dict ) )
20−import Rel8.Schema.Kind ( Context, HContext )
21−import Rel8.Schema.Spec ( Spec( Spec ) )
22−import Rel8.Schema.Result ( Result )
23−import Rel8.Schema.Spec.ConstrainDBType ( ConstrainDBType )
24−
25−
26−type Labelable :: Context -> Constraint
27−class Interpretation context => Labelable context where
28− labeler :: ()
29− => Col context ('Spec labels necessity a)
30− -> Col context ('Spec (label ': labels) necessity a)
31−
32− unlabeler :: ()
33− => Col context ('Spec (label ': labels) necessity a)
34− -> Col context ('Spec labels necessity a)
35−
36−
37−instance Labelable Result where
38− labeler (Result a) = Result a
39− unlabeler (Result a) = Result a
40−
41−
42−type HLabelable :: HContext -> Constraint
43−class HLabelable context where
44− hlabeler :: ()
45− => context ('Spec labels necessity a)
46− -> context ('Spec (label ': labels) necessity a)
47−
48− hunlabeler :: ()
49− => context ('Spec (label ': labels) necessity a)
50− -> context ('Spec labels necessity a)
51−
52−
53−instance Labelable context => HLabelable (Col context) where
54− hlabeler = labeler
55− hunlabeler = unlabeler
56−
57−
58−instance HLabelable (Dict (ConstrainDBType constraint)) where
59− hlabeler Dict = Dict
60− hunlabeler Dict = Dict
src/Rel8/Schema/Context/Nullify.hs+105−160
@@ -1,199 +1,144 @@
11{-# language DataKinds #-}
2+{-# language EmptyCase #-}
23{-# language FlexibleContexts #-}
3−{-# language FlexibleInstances #-}
4−{-# language InstanceSigs #-}
5−{-# language MultiParamTypeClasses #-}
4+{-# language GADTs #-}
5+{-# language LambdaCase #-}
66{-# language NamedFieldPuns #-}
7−{-# language ScopedTypeVariables #-}
87{-# language StandaloneKindSignatures #-}
9−{-# language TypeFamilies #-}
108
119module Rel8.Schema.Context.Nullify
12− ( Nullifiable( ConstrainTag, encodeTag, decodeTag, nullifier, unnullifier )
13− , HNullifiable( HConstrainTag, hencodeTag, hdecodeTag, hnullifier, hunnullifier )
14− , runTag, unnull
10+ ( Nullifiability(..), NonNullifiability(..), nullifiableOrNot, absurd
11+ , Nullifiable, nullifiability
12+ , guarder, nullifier, unnullifier
13+ , sguard, snullify
1514 )
1615where
1716
1817-- base
18+import Data.Bool ( bool )
19+import Data.Functor.Identity ( Identity( Identity ) )
1920import Data.Kind ( Constraint, Type )
20−import GHC.TypeLits ( KnownSymbol )
2121import Prelude hiding ( null )
2222
2323-- opaleye
2424import qualified Opaleye.Internal.HaskellDB.PrimQuery as Opaleye
2525
2626-- rel8
27−import Rel8.Aggregate
28− ( Aggregate, Col(..)
29− , mapInputs
30− , unsafeMakeAggregate
31− )
32−import Rel8.Expr ( Expr, Col(..) )
27+import Rel8.Aggregate ( Aggregate(..), zipOutputs )
28+import Rel8.Expr ( Expr )
3329import Rel8.Expr.Bool ( boolExpr )
3430import Rel8.Expr.Null ( nullify, unsafeUnnullify )
35−import Rel8.Expr.Opaleye ( fromPrimExpr, toPrimExpr )
36−import Rel8.Kind.Necessity ( Necessity( Required ) )
37−import Rel8.Schema.Context ( Interpretation )
31+import Rel8.Expr.Opaleye ( fromPrimExpr )
32+import Rel8.Kind.Context ( SContext(..) )
33+import Rel8.Schema.Field ( Field )
3834import qualified Rel8.Schema.Kind as K
39−import Rel8.Schema.Name ( Name( Name ), Col(..) )
40−import Rel8.Schema.Null ( Nullify, Nullity( Null, NotNull ), Sql )
41−import Rel8.Schema.Dict ( Dict( Dict ) )
42−import Rel8.Schema.Spec ( Spec( Spec ), SSpec(..) )
43−import Rel8.Schema.Spec.ConstrainDBType
44− ( ConstrainDBType
45− , dbTypeDict, dbTypeNullity, fromNullityDict
46− )
47−import Rel8.Table.Tag ( Tag(..), Taggable, fromAggregate, fromExpr, fromName )
35+import Rel8.Schema.Name ( Name( Name ) )
36+import Rel8.Schema.Null ( Nullify, Nullity( Null, NotNull ) )
37+import Rel8.Schema.Result ( Result )
38+import Rel8.Schema.Spec ( Spec(..) )
4839
4940
50−type Nullifiable :: K.Context -> Constraint
51−class Interpretation context => Nullifiable context where
52− type ConstrainTag context :: Type -> Constraint
53− type ConstrainTag _context = DefaultConstrainTag
54−
55− encodeTag ::
56− ( Sql (ConstrainTag context) a
57− , KnownSymbol label
58− , Taggable a
59− )
60− => Tag label a
61− -> Col context ('Spec labels 'Required a)
62−
63− decodeTag ::
64− ( Sql (ConstrainTag context) a
65− , KnownSymbol label
66− , Taggable a
67− )
68− => Col context ('Spec labels 'Required a)
69− -> Tag label a
70−
71− nullifier :: ()
72− => Tag label a
73− -> (Expr a -> Expr Bool)
74− -> SSpec ('Spec labels necessity x)
75− -> Col context ('Spec labels necessity x)
76− -> Col context ('Spec labels necessity (Nullify x))
77−
78− unnullifier :: ()
79− => SSpec ('Spec labels necessity x)
80− -> Col context ('Spec labels necessity (Nullify x))
81− -> Col context ('Spec labels necessity x)
41+type Nullifiability :: K.Context -> Type
42+data Nullifiability context where
43+ NAggregate :: Nullifiability Aggregate
44+ NExpr :: Nullifiability Expr
45+ NName :: Nullifiability Name
8246
8347
84−instance Nullifiable Aggregate where
85− encodeTag Tag {aggregator, expr} =
86− Aggregation $ unsafeMakeAggregate toPrimExpr fromPrimExpr aggregator expr
87−
88− decodeTag (Aggregation aggregate) = fromAggregate aggregate
89−
90− nullifier Tag {expr} test SSpec {nullity} (Aggregation aggregate) =
91− Aggregation $
92− mapInputs (toPrimExpr . runTag nullity condition . fromPrimExpr) $
93− runTag nullity condition <$> aggregate
94− where
95− condition = test expr
48+type Nullifiable :: K.Context -> Constraint
49+class Nullifiable context where
50+ nullifiability :: Nullifiability context
9651
97− unnullifier SSpec {nullity} (Aggregation aggregate) =
98− Aggregation $ unnull nullity <$> aggregate
9952
100− {-# INLINABLE encodeTag #-}
101− {-# INLINABLE decodeTag #-}
102− {-# INLINABLE nullifier #-}
103− {-# INLINABLE unnullifier #-}
53+instance Nullifiable Aggregate where
54+ nullifiability = NAggregate
10455
10556
10657instance Nullifiable Expr where
107− encodeTag Tag {expr} = DB expr
108− decodeTag (DB a) = fromExpr a
109− nullifier Tag {expr} test SSpec {nullity} (DB a) =
110− DB $ runTag nullity (test expr) a
111− unnullifier SSpec {nullity} (DB a) = DB $ unnull nullity a
112−
113− {-# INLINABLE encodeTag #-}
114− {-# INLINABLE decodeTag #-}
115− {-# INLINABLE nullifier #-}
116− {-# INLINABLE unnullifier #-}
58+ nullifiability = NExpr
11759
11860
11961instance Nullifiable Name where
120− encodeTag Tag {name = Name name} = NameCol name
121− decodeTag (NameCol name) = fromName (Name name)
122− nullifier _ _ _ (NameCol name) = NameCol name
123− unnullifier _ (NameCol name) = NameCol name
124−
125− {-# INLINABLE encodeTag #-}
126− {-# INLINABLE decodeTag #-}
127− {-# INLINABLE nullifier #-}
128− {-# INLINABLE unnullifier #-}
129−
130−
131−runTag :: Nullity a -> Expr Bool -> Expr a -> Expr (Nullify a)
132−runTag nullity tag a = case nullity of
133− Null -> boolExpr null a tag
134− NotNull -> boolExpr null (nullify a) tag
62+ nullifiability = NName
63+
64+
65+type NonNullifiability :: K.Context -> Type
66+data NonNullifiability context where
67+ NField :: NonNullifiability (Field table)
68+ NResult :: NonNullifiability Result
69+
70+
71+nullifiableOrNot :: ()
72+ => SContext context
73+ -> Either (NonNullifiability context) (Nullifiability context)
74+nullifiableOrNot = \case
75+ SAggregate -> Right NAggregate
76+ SExpr -> Right NExpr
77+ SField -> Left NField
78+ SName -> Right NName
79+ SResult -> Left NResult
80+
81+
82+absurd :: Nullifiability context -> NonNullifiability context -> a
83+absurd = \case
84+ NAggregate -> \case
85+ NExpr -> \case
86+ NName -> \case
87+
88+
89+guarder :: ()
90+ => SContext context
91+ -> context tag
92+ -> (tag -> Bool)
93+ -> (Expr tag -> Expr Bool)
94+ -> context (Maybe a)
95+ -> context (Maybe a)
96+guarder = \case
97+ SAggregate -> \tag _ isNonNull -> zipOutputs (sguard . isNonNull) tag
98+ SExpr -> \tag _ isNonNull -> sguard (isNonNull tag)
99+ SField -> \_ _ _ -> id
100+ SName -> \_ _ _ -> id
101+ SResult -> \(Identity tag) isNonNull _ (Identity a) ->
102+ Identity (bool Nothing a (isNonNull tag))
103+
104+
105+nullifier :: ()
106+ => Nullifiability context
107+ -> Spec a
108+ -> context a
109+ -> context (Nullify a)
110+nullifier = \case
111+ NAggregate -> \Spec {nullity} (Aggregate a) ->
112+ Aggregate $ snullify nullity <$> a
113+ NExpr -> \Spec {nullity} a -> snullify nullity a
114+ NName -> \_ (Name a) -> Name a
115+
116+
117+unnullifier :: ()
118+ => Nullifiability context
119+ -> Spec a
120+ -> context (Nullify a)
121+ -> context a
122+unnullifier = \case
123+ NAggregate -> \Spec {nullity} (Aggregate a) ->
124+ Aggregate $ sunnullify nullity <$> a
125+ NExpr -> \Spec {nullity} a -> sunnullify nullity a
126+ NName -> \_ (Name a) -> Name a
127+
128+
129+sguard :: Expr Bool -> Expr (Maybe a) -> Expr (Maybe a)
130+sguard condition a = boolExpr null a condition
135131 where
136132 null = fromPrimExpr $ Opaleye.ConstExpr Opaleye.NullLit
137133
138134
139−unnull :: Nullity a -> Expr (Nullify a) -> Expr a
140−unnull nullity a = case nullity of
135+snullify :: Nullity a -> Expr a -> Expr (Nullify a)
136+snullify nullity a = case nullity of
141137 Null -> a
142− NotNull -> unsafeUnnullify a
143−
138+ NotNull -> nullify a
144139
145−type HNullifiable :: K.HContext -> Constraint
146−class HNullifiable context where
147− type HConstrainTag context :: Type -> Constraint
148− type HConstrainTag _context = DefaultConstrainTag
149140
150− hencodeTag :: (Sql (HConstrainTag context) a, KnownSymbol label, Taggable a)
151− => Tag label a
152− -> context ('Spec labels 'Required a)
153−
154− hdecodeTag :: (Sql (HConstrainTag context) a, KnownSymbol label, Taggable a)
155− => context ('Spec labels 'Required a)
156− -> Tag label a
157−
158− hnullifier :: ()
159− => Tag label a
160− -> (Expr a -> Expr Bool)
161− -> SSpec ('Spec labels necessity x)
162− -> context ('Spec labels necessity x)
163− -> context ('Spec labels necessity (Nullify x))
164−
165− hunnullifier :: ()
166− => SSpec ('Spec labels necessity x)
167− -> context ('Spec labels necessity (Nullify x))
168− -> context ('Spec labels necessity x)
169−
170−
171−instance Nullifiable context => HNullifiable (Col context) where
172− type HConstrainTag (Col context) = ConstrainTag context
173− hencodeTag = encodeTag
174− hdecodeTag = decodeTag
175− hnullifier = nullifier
176− hunnullifier = unnullifier
177−
178−
179−instance HNullifiable (Dict (ConstrainDBType constraint)) where
180− type HConstrainTag (Dict (ConstrainDBType constraint)) = constraint
181−
182− hencodeTag _ = Dict
183− hdecodeTag = mempty
184−
185− hnullifier _ _ SSpec {} dict = case dbTypeDict dict of
186− Dict -> case dbTypeNullity dict of
187− Null -> Dict
188− NotNull -> Dict
189−
190− hunnullifier SSpec {nullity} dict = case dbTypeDict dict of
191− Dict -> case nullity of
192− Null -> Dict
193− NotNull -> case dbTypeNullity dict of
194− Null -> fromNullityDict nullity Dict
195−
196−
197−type DefaultConstrainTag :: Type -> Constraint
198−class DefaultConstrainTag a
199−instance DefaultConstrainTag a
141+sunnullify :: Nullity a -> Expr (Nullify a) -> Expr a
142+sunnullify nullity a = case nullity of
143+ Null -> a
144+ NotNull -> unsafeUnnullify a
src/Rel8/Schema/Field.hs+23−694
@@ -1,721 +1,50 @@
11{-# language DataKinds #-}
22{-# language FlexibleContexts #-}
3−{-# language GADTs #-}
4−{-# language LambdaCase #-}
53{-# language MultiParamTypeClasses #-}
64{-# language StandaloneKindSignatures #-}
75{-# language TypeFamilies #-}
8−{-# language UndecidableInstances #-}
96
107module Rel8.Schema.Field
11− ( Field
12− , HEither, HList, HMaybe, HNonEmpty, HThese
13− , Reify, hreify, hunreify
14− , Reifiable(..)
15− , AField(..)
16− , AHEither(..), AHList(..), AHMaybe(..), AHNonEmpty(..), AHThese(..)
17− , SContext(..)
8+ ( Field(..)
9+ , fields
1810 )
1911where
2012
2113-- base
22−import Data.Bifunctor ( Bifunctor, bimap )
23−import Data.Kind ( Constraint, Type )
24−import Data.List.NonEmpty ( NonEmpty )
14+import Data.Functor.Identity ( Identity( Identity ) )
15+import Data.Kind ( Type )
2516import Prelude
2617
2718-- rel8
28−import Rel8.Aggregate ( Aggregate, Col(..) )
29−import Rel8.Expr ( Expr, Col(..) )
30−import Rel8.Kind.Necessity
31− ( Necessity( Required, Optional )
32− , SNecessity( SRequired, SOptional )
33− , KnownNecessity, necessitySing
34− )
35−import Rel8.Schema.Context ( Interpretation, Col(..) )
36−import Rel8.Schema.Context.Label ( Labelable, labeler, unlabeler )
37−import Rel8.Schema.HTable ( HTable, hfield, htabulate )
38−import Rel8.Schema.HTable.Either ( HEitherTable )
39−import Rel8.Schema.HTable.List ( HListTable )
40−import Rel8.Schema.HTable.Maybe ( HMaybeTable )
41−import Rel8.Schema.HTable.NonEmpty ( HNonEmptyTable )
42−import Rel8.Schema.HTable.These ( HTheseTable )
19+import Rel8.Schema.HTable ( HField, htabulate )
4320import Rel8.Schema.HTable.Identity ( HIdentity( HIdentity ) )
44−import Rel8.Schema.Insert ( Insert, Col(..) )
45−import qualified Rel8.Schema.Kind as K
46−import Rel8.Schema.Name ( Name(..), Col(..) )
21+import Rel8.Schema.Kind as K
4722import Rel8.Schema.Null ( Sql )
48−import Rel8.Schema.Result ( Result )
49−import Rel8.Schema.Spec ( Spec( Spec ) )
5023import Rel8.Table
5124 ( Table, Columns, Context, fromColumns, toColumns
52− , Congruent
25+ , FromExprs, fromResult, toResult
26+ , Transpose
5327 )
54−import Rel8.Table.Either ( EitherTable )
55−import Rel8.Table.List ( ListTable( ListTable ) )
56−import Rel8.Table.Maybe ( MaybeTable )
57−import Rel8.Table.NonEmpty ( NonEmptyTable( NonEmptyTable ) )
58−import Rel8.Table.Recontextualize ( Recontextualize )
59−import Rel8.Table.These ( TheseTable )
28+import Rel8.Table.Transpose ( Transposes )
6029import Rel8.Type ( DBType )
6130
62−-- these
63−import Data.These ( These )
64−
65−
66−type Field :: K.Context -> Necessity -> Type -> Type
67−type family Field context necessity a where
68− Field (Reify context) necessity a = AField context necessity a
69− Field Aggregate _necessity a = Aggregate (Expr a)
70− Field Expr _necessity a = Expr a
71− Field Insert 'Required a = Expr a
72− Field Insert 'Optional a = Maybe (Expr a)
73− Field Name _necessity a = Name a
74− Field Result _necessity a = a
75−
76−
77−type HEither :: K.Context -> Type -> Type -> Type
78−type family HEither context where
79− HEither (Reify context) = AHEither context
80− HEither Aggregate = EitherTable
81− HEither Expr = EitherTable
82− HEither Insert = EitherTable
83− HEither Name = EitherTable
84− HEither Result = Either
85−
86−
87−type HList :: K.Context -> Type -> Type
88−type family HList context where
89− HList (Reify context) = AHList context
90− HList Aggregate = ListTable
91− HList Expr = ListTable
92− HList Insert = ListTable
93− HList Name = ListTable
94− HList Result = []
95−
96−
97−type HMaybe :: K.Context -> Type -> Type
98−type family HMaybe context where
99− HMaybe (Reify context) = AHMaybe context
100− HMaybe Aggregate = MaybeTable
101− HMaybe Expr = MaybeTable
102− HMaybe Insert = MaybeTable
103− HMaybe Name = MaybeTable
104− HMaybe Result = Maybe
105−
106−
107−type HNonEmpty :: K.Context -> Type -> Type
108−type family HNonEmpty context where
109− HNonEmpty (Reify context) = AHNonEmpty context
110− HNonEmpty Aggregate = NonEmptyTable
111− HNonEmpty Expr = NonEmptyTable
112− HNonEmpty Insert = NonEmptyTable
113− HNonEmpty Name = NonEmptyTable
114− HNonEmpty Result = NonEmpty
115−
116−
117−type HThese :: K.Context -> Type -> Type -> Type
118−type family HThese context where
119− HThese (Reify context) = AHThese context
120− HThese Aggregate = TheseTable
121− HThese Expr = TheseTable
122− HThese Insert = TheseTable
123− HThese Name = TheseTable
124− HThese Result = These
125−
126−
127−type AField :: K.Context -> Necessity -> Type -> Type
128−newtype AField context necessity a = AField (Field context necessity a)
129−
130−
131−instance (Reifiable context, KnownNecessity necessity, Sql DBType a) =>
132− Table (Reify context) (AField context necessity a)
133− where
134− type Context (AField context necessity a) = Reify context
135− type Columns (AField context necessity a) = HIdentity ('Spec '[""] necessity a)
136−
137− fromColumns (HIdentity (Reify a)) = sfromColumn contextSing a
138− toColumns = HIdentity . Reify . stoColumn contextSing necessitySing
139−
140−
141−instance
142− ( Reifiable context, Reifiable context'
143− , KnownNecessity necessity, Sql DBType a
144− ) =>
145− Recontextualize
146− (Reify context)
147− (Reify context')
148− (AField context necessity a)
149− (AField context' necessity a)
150−
151−
152−type AHEither :: K.Context -> Type -> Type -> Type
153−newtype AHEither context a b = AHEither (HEither context a b)
154−
155−
156−instance Reifiable context => Bifunctor (AHEither context) where
157− bimap = sbimapEither contextSing
158−
159−
160−instance Reifiable context => Functor (AHEither context a) where
161− fmap = bimap id
162−
163−
164−instance (Reifiable context, Table (Reify context) a, Table (Reify context) b)
165− => Table (Reify context) (AHEither context a b)
166− where
167− type Context (AHEither context a b) = Reify context
168− type Columns (AHEither context a b) = HEitherTable (Columns a) (Columns b)
169−
170− fromColumns = sfromColumnsEither contextSing
171− toColumns = stoColumnsEither contextSing
172−
173−
174−instance
175− ( Reifiable context, Reifiable context'
176− , Recontextualize (Reify context) (Reify context') a a'
177− , Recontextualize (Reify context) (Reify context') b b'
178− ) =>
179− Recontextualize
180− (Reify context)
181− (Reify context')
182− (AHEither context a b)
183− (AHEither context' a' b')
184−
185−
186−type AHList :: K.Context -> Type -> Type
187−newtype AHList context a = AHList (HList context a)
188−
189−
190−instance (Reifiable context, Table (Reify context) a) =>
191− Table (Reify context) (AHList context a)
192− where
193− type Context (AHList context a) = Reify context
194− type Columns (AHList context a) = HListTable (Columns a)
195−
196− fromColumns = sfromColumnsList contextSing
197− toColumns = stoColumnsList contextSing
198−
199−
200−instance
201− ( Reifiable context, Reifiable context'
202− , Recontextualize (Reify context) (Reify context') a a'
203− ) =>
204− Recontextualize
205− (Reify context)
206− (Reify context')
207− (AHList context a)
208− (AHList context' a')
209−
210−
211−type AHMaybe :: K.Context -> Type -> Type
212−newtype AHMaybe context a = AHMaybe (HMaybe context a)
213−
214−
215−instance Reifiable context => Functor (AHMaybe context) where
216− fmap = smapMaybe contextSing
217−
218−
219−instance (Reifiable context, Table (Reify context) a) =>
220− Table (Reify context) (AHMaybe context a)
221− where
222− type Context (AHMaybe context a) = Reify context
223− type Columns (AHMaybe context a) = HMaybeTable (Columns a)
224−
225− fromColumns = sfromColumnsMaybe contextSing
226− toColumns = stoColumnsMaybe contextSing
227−
228−
229−instance
230− ( Reifiable context, Reifiable context'
231− , Recontextualize (Reify context) (Reify context') a a'
232− ) =>
233− Recontextualize
234− (Reify context)
235− (Reify context')
236− (AHMaybe context a)
237− (AHMaybe context' a')
238−
239−
240−type AHNonEmpty :: K.Context -> Type -> Type
241−newtype AHNonEmpty context a = AHNonEmpty (HNonEmpty context a)
242−
243−
244−instance (Reifiable context, Table (Reify context) a) =>
245− Table (Reify context) (AHNonEmpty context a)
246− where
247− type Context (AHNonEmpty context a) = Reify context
248− type Columns (AHNonEmpty context a) = HNonEmptyTable (Columns a)
249−
250− fromColumns = sfromColumnsNonEmpty contextSing
251− toColumns = stoColumnsNonEmpty contextSing
252−
253−
254−instance
255− ( Reifiable context, Reifiable context'
256− , Recontextualize (Reify context) (Reify context') a a'
257− ) =>
258− Recontextualize
259− (Reify context)
260− (Reify context')
261− (AHNonEmpty context a)
262− (AHNonEmpty context' a')
263−
264−
265−type AHThese :: K.Context -> Type -> Type -> Type
266−newtype AHThese context a b = AHThese (HThese context a b)
267−
268−
269−instance Reifiable context => Bifunctor (AHThese context) where
270− bimap = sbimapThese contextSing
271−
272−
273−instance Reifiable context => Functor (AHThese context a) where
274− fmap = bimap id
275−
276−
277−instance (Reifiable context, Table (Reify context) a, Table (Reify context) b)
278− => Table (Reify context) (AHThese context a b)
279− where
280− type Context (AHThese context a b) = Reify context
281− type Columns (AHThese context a b) = HTheseTable (Columns a) (Columns b)
282−
283− fromColumns = sfromColumnsThese contextSing
284− toColumns = stoColumnsThese contextSing
285−
286−
287−instance
288− ( Reifiable context, Reifiable context'
289− , Recontextualize (Reify context) (Reify context') a a'
290− , Recontextualize (Reify context) (Reify context') b b'
291− ) =>
292− Recontextualize
293− (Reify context)
294− (Reify context')
295− (AHThese context a b)
296− (AHThese context' a' b')
297−
298−
299−type SContext :: K.Context -> Type
300−data SContext context where
301− SAggregate :: SContext Aggregate
302− SExpr :: SContext Expr
303− SInsert :: SContext Insert
304− SName :: SContext Name
305− SResult :: SContext Result
306− SReify :: SContext context -> SContext (Reify context)
307−
308−
309−type Reifiable :: K.Context -> Constraint
310−class Interpretation context => Reifiable context where
311− contextSing :: SContext context
312−
313−
314−instance Reifiable Aggregate where
315− contextSing = SAggregate
316−
317−
318−instance Reifiable Expr where
319− contextSing = SExpr
320−
321−
322−instance Reifiable Result where
323− contextSing = SResult
324−
325−
326−instance Reifiable Insert where
327− contextSing = SInsert
328−
329−
330−instance Reifiable Name where
331− contextSing = SName
332−
333−
334−type Reify :: K.Context -> K.Context
335−data Reify context a
336−
337−
338−instance Interpretation (Reify context) where
339− newtype Col (Reify context) spec = Reify (Col context spec)
340−
341−
342−instance Labelable context => Labelable (Reify context) where
343− labeler (Reify a) = Reify (labeler a)
344− unlabeler (Reify a) = Reify (unlabeler a)
345−
346−
347−instance Reifiable context => Reifiable (Reify context) where
348− contextSing = SReify contextSing
349−
350−
351−sfromColumn :: ()
352− => SContext context
353− -> Col context ('Spec labels necessity a)
354− -> AField context necessity a
355−sfromColumn = \case
356− SAggregate -> \(Aggregation a) -> AField a
357− SExpr -> \(DB a) -> AField a
358− SResult -> \(Result a) -> AField a
359− SInsert -> \case
360− RequiredInsert a -> AField a
361− OptionalInsert a -> AField a
362− SName -> \(NameCol a) -> AField (Name a)
363− SReify context -> \(Reify a) -> AField (sfromColumn context a)
364−
365−
366−stoColumn :: ()
367− => SContext context
368− -> SNecessity necessity
369− -> AField context necessity a
370− -> Col context ('Spec labels necessity a)
371−stoColumn = \case
372− SAggregate -> \_ (AField a) -> Aggregation a
373− SExpr -> \_ (AField a) -> DB a
374− SResult -> \_ (AField a) -> Result a
375− SInsert -> \case
376− SRequired -> \(AField a) -> RequiredInsert a
377− SOptional -> \(AField a) -> OptionalInsert a
378− SName -> \_ (AField (Name a)) -> NameCol a
379− SReify context ->
380− \necessity (AField a) -> Reify (stoColumn context necessity a)
381−
382−
383−sbimapEither :: ()
384− => SContext context
385− -> (a -> c)
386− -> (b -> d)
387− -> AHEither context a b
388− -> AHEither context c d
389−sbimapEither = \case
390− SAggregate -> \f g (AHEither a) -> AHEither (bimap f g a)
391− SExpr -> \f g (AHEither a) -> AHEither (bimap f g a)
392− SResult -> \f g (AHEither a) -> AHEither (bimap f g a)
393− SInsert -> \f g (AHEither a) -> AHEither (bimap f g a)
394− SName -> \f g (AHEither a) -> AHEither (bimap f g a)
395− SReify context -> \f g (AHEither a) -> AHEither (sbimapEither context f g a)
396−
397−
398−sfromColumnsEither :: (Table (Reify context) a, Table (Reify context) b)
399− => SContext context
400− -> HEitherTable (Columns a) (Columns b) (Col (Reify context))
401− -> AHEither context a b
402−sfromColumnsEither = \case
403− SAggregate ->
404− AHEither .
405− bimap (fromColumns . hreify) (fromColumns . hreify) .
406− fromColumns .
407− hunreify
408− SExpr ->
409− AHEither .
410− bimap (fromColumns . hreify) (fromColumns . hreify) .
411− fromColumns .
412− hunreify
413− SResult ->
414− AHEither .
415− bimap (fromColumns . hreify) (fromColumns . hreify) .
416− fromColumns .
417− hunreify
418− SInsert ->
419− AHEither .
420− bimap (fromColumns . hreify) (fromColumns . hreify) .
421− fromColumns .
422− hunreify
423− SName ->
424− AHEither .
425− bimap (fromColumns . hreify) (fromColumns . hreify) .
426− fromColumns .
427− hunreify
428− SReify context ->
429− AHEither .
430− sbimapEither context (fromColumns . hreify) (fromColumns . hreify) .
431− sfromColumnsEither context .
432− hunreify
433−
434−
435−stoColumnsEither :: (Table (Reify context) a, Table (Reify context) b)
436− => SContext context
437− -> AHEither context a b
438− -> HEitherTable (Columns a) (Columns b) (Col (Reify context))
439−stoColumnsEither = \case
440− SAggregate ->
441− hreify .
442− toColumns .
443− bimap (hunreify . toColumns) (hunreify . toColumns) .
444− (\(AHEither a) -> a)
445− SExpr ->
446− hreify .
447− toColumns .
448− bimap (hunreify . toColumns) (hunreify . toColumns) .
449− (\(AHEither a) -> a)
450− SResult ->
451− hreify .
452− toColumns .
453− bimap (hunreify . toColumns) (hunreify . toColumns) .
454− (\(AHEither a) -> a)
455− SInsert ->
456− hreify .
457− toColumns .
458− bimap (hunreify . toColumns) (hunreify . toColumns) .
459− (\(AHEither a) -> a)
460− SName ->
461− hreify .
462− toColumns .
463− bimap (hunreify . toColumns) (hunreify . toColumns) .
464− (\(AHEither a) -> a)
465− SReify context ->
466− hreify .
467− stoColumnsEither context .
468− sbimapEither context (hunreify . toColumns) (hunreify . toColumns) .
469− (\(AHEither a) -> a)
470−
471−
472−smapList :: Congruent a b
473− => SContext context
474− -> (a -> b)
475− -> (HListTable (Columns a) (Col (Context a)) -> HListTable (Columns b) (Col (Context b)))
476− -> AHList context a
477− -> AHList context b
478−smapList = \case
479− SAggregate -> \_ f (AHList (ListTable a)) -> AHList (ListTable (f a))
480− SExpr -> \_ f (AHList (ListTable a)) -> AHList (ListTable (f a))
481− SResult -> \f _ (AHList as) -> AHList (fmap f as)
482− SInsert -> \_ f (AHList (ListTable a)) -> AHList (ListTable (f a))
483− SName -> \_ f (AHList (ListTable a)) -> AHList (ListTable (f a))
484− SReify context -> \f g (AHList as) -> AHList (smapList context f g as)
485−
486−
487−sfromColumnsList :: Table (Reify context) a
488− => SContext context
489− -> HListTable (Columns a) (Col (Reify context))
490− -> AHList context a
491−sfromColumnsList = \case
492− SAggregate -> AHList . ListTable
493− SExpr -> AHList . ListTable
494− SResult -> AHList . fmap (fromColumns . hreify) . fromColumns . hunreify
495− SInsert -> AHList . ListTable
496− SName -> AHList . ListTable
497− SReify context ->
498− AHList .
499− smapList context (fromColumns . hreify) hreify .
500− sfromColumnsList context .
501− hunreify
502−
503−
504−stoColumnsList :: Table (Reify context) a
505− => SContext context
506− -> AHList context a
507− -> HListTable (Columns a) (Col (Reify context))
508−stoColumnsList = \case
509− SAggregate -> \(AHList (ListTable a)) -> a
510− SExpr -> \(AHList (ListTable a)) -> a
511− SResult ->
512− hreify . toColumns . fmap (hunreify . toColumns) . (\(AHList a) -> a)
513− SInsert -> \(AHList (ListTable a)) -> a
514− SName -> \(AHList (ListTable a)) -> a
515− SReify context ->
516− hreify .
517− stoColumnsList context .
518− smapList context (hunreify . toColumns) hunreify .
519− (\(AHList a) -> a)
520−
521−
522−smapMaybe :: ()
523− => SContext context
524− -> (a -> b)
525− -> AHMaybe context a
526− -> AHMaybe context b
527−smapMaybe = \case
528− SAggregate -> \f (AHMaybe a) -> AHMaybe (fmap f a)
529− SExpr -> \f (AHMaybe a) -> AHMaybe (fmap f a)
530− SResult -> \f (AHMaybe a) -> AHMaybe (fmap f a)
531− SInsert -> \f (AHMaybe a) -> AHMaybe (fmap f a)
532− SName -> \f (AHMaybe a) -> AHMaybe (fmap f a)
533− SReify context -> \f (AHMaybe a) -> AHMaybe (smapMaybe context f a)
534−
535−
536−sfromColumnsMaybe :: Table (Reify context) a
537− => SContext context
538− -> HMaybeTable (Columns a) (Col (Reify context))
539− -> AHMaybe context a
540−sfromColumnsMaybe = \case
541− SAggregate -> AHMaybe . fmap (fromColumns . hreify) . fromColumns . hunreify
542− SExpr -> AHMaybe . fmap (fromColumns . hreify) . fromColumns . hunreify
543− SResult -> AHMaybe . fmap (fromColumns . hreify) . fromColumns . hunreify
544− SInsert -> AHMaybe . fmap (fromColumns . hreify) . fromColumns . hunreify
545− SName -> AHMaybe . fmap (fromColumns . hreify) . fromColumns . hunreify
546− SReify context ->
547− AHMaybe .
548− smapMaybe context (fromColumns . hreify) .
549− sfromColumnsMaybe context .
550− hunreify
551−
552−
553−stoColumnsMaybe :: Table (Reify context) a
554− => SContext context
555− -> AHMaybe context a
556− -> HMaybeTable (Columns a) (Col (Reify context))
557−stoColumnsMaybe = \case
558− SAggregate ->
559− hreify . toColumns . fmap (hunreify . toColumns) . (\(AHMaybe a) -> a)
560− SExpr ->
561− hreify . toColumns . fmap (hunreify . toColumns) . (\(AHMaybe a) -> a)
562− SResult ->
563− hreify . toColumns . fmap (hunreify . toColumns) . (\(AHMaybe a) -> a)
564− SInsert ->
565− hreify . toColumns . fmap (hunreify . toColumns) . (\(AHMaybe a) -> a)
566− SName ->
567− hreify . toColumns . fmap (hunreify . toColumns) . (\(AHMaybe a) -> a)
568− SReify context ->
569− hreify .
570− stoColumnsMaybe context .
571− smapMaybe context (hunreify . toColumns) .
572− (\(AHMaybe a) -> a)
573−
574−
575−smapNonEmpty :: Congruent a b
576− => SContext context
577− -> (a -> b)
578− -> (HNonEmptyTable (Columns a) (Col (Context a)) -> HNonEmptyTable (Columns b) (Col (Context b)))
579− -> AHNonEmpty context a
580− -> AHNonEmpty context b
581−smapNonEmpty = \case
582− SAggregate -> \_ f (AHNonEmpty (NonEmptyTable a)) -> AHNonEmpty (NonEmptyTable (f a))
583− SExpr -> \_ f (AHNonEmpty (NonEmptyTable a)) -> AHNonEmpty (NonEmptyTable (f a))
584− SResult -> \f _ (AHNonEmpty as) -> AHNonEmpty (fmap f as)
585− SInsert -> \_ f (AHNonEmpty (NonEmptyTable a)) -> AHNonEmpty (NonEmptyTable (f a))
586− SName -> \_ f (AHNonEmpty (NonEmptyTable a)) -> AHNonEmpty (NonEmptyTable (f a))
587− SReify context -> \f g (AHNonEmpty as) -> AHNonEmpty (smapNonEmpty context f g as)
588−
589−
590−sfromColumnsNonEmpty :: Table (Reify context) a
591− => SContext context
592− -> HNonEmptyTable (Columns a) (Col (Reify context))
593− -> AHNonEmpty context a
594−sfromColumnsNonEmpty = \case
595− SAggregate -> AHNonEmpty . NonEmptyTable
596− SExpr -> AHNonEmpty . NonEmptyTable
597− SResult ->
598− AHNonEmpty . fmap (fromColumns . hreify) . fromColumns . hunreify
599− SInsert -> AHNonEmpty . NonEmptyTable
600− SName -> AHNonEmpty . NonEmptyTable
601− SReify context ->
602− AHNonEmpty .
603− smapNonEmpty context (fromColumns . hreify) hreify .
604− sfromColumnsNonEmpty context .
605− hunreify
606−
607−
608−stoColumnsNonEmpty :: Table (Reify context) a
609− => SContext context
610− -> AHNonEmpty context a
611− -> HNonEmptyTable (Columns a) (Col (Reify context))
612−stoColumnsNonEmpty = \case
613− SAggregate -> \(AHNonEmpty (NonEmptyTable a)) -> a
614− SExpr -> \(AHNonEmpty (NonEmptyTable a)) -> a
615− SResult ->
616− hreify . toColumns . fmap (hunreify . toColumns) . (\(AHNonEmpty a) -> a)
617− SInsert -> \(AHNonEmpty (NonEmptyTable a)) -> a
618− SName -> \(AHNonEmpty (NonEmptyTable a)) -> a
619− SReify context ->
620− hreify .
621− stoColumnsNonEmpty context .
622− smapNonEmpty context (hunreify . toColumns) hunreify .
623− (\(AHNonEmpty a) -> a)
624−
625−
626−sbimapThese :: ()
627− => SContext context
628− -> (a -> c)
629− -> (b -> d)
630− -> AHThese context a b
631− -> AHThese context c d
632−sbimapThese = \case
633− SAggregate -> \f g (AHThese a) -> AHThese (bimap f g a)
634− SExpr -> \f g (AHThese a) -> AHThese (bimap f g a)
635− SResult -> \f g (AHThese a) -> AHThese (bimap f g a)
636− SInsert -> \f g (AHThese a) -> AHThese (bimap f g a)
637− SName -> \f g (AHThese a) -> AHThese (bimap f g a)
638− SReify context -> \f g (AHThese a) -> AHThese (sbimapThese context f g a)
639−
640−
641−sfromColumnsThese :: (Table (Reify context) a, Table (Reify context) b)
642− => SContext context
643− -> HTheseTable (Columns a) (Columns b) (Col (Reify context))
644− -> AHThese context a b
645−sfromColumnsThese = \case
646− SAggregate ->
647− AHThese .
648− bimap (fromColumns . hreify) (fromColumns . hreify) .
649− fromColumns .
650− hunreify
651− SExpr ->
652− AHThese .
653− bimap (fromColumns . hreify) (fromColumns . hreify) .
654− fromColumns .
655− hunreify
656− SResult ->
657− AHThese .
658− bimap (fromColumns . hreify) (fromColumns . hreify) .
659− fromColumns .
660− hunreify
661− SInsert ->
662− AHThese .
663− bimap (fromColumns . hreify) (fromColumns . hreify) .
664− fromColumns .
665− hunreify
666− SName ->
667− AHThese .
668− bimap (fromColumns . hreify) (fromColumns . hreify) .
669− fromColumns .
670− hunreify
671− SReify context ->
672− AHThese .
673− sbimapThese context (fromColumns . hreify) (fromColumns . hreify) .
674− sfromColumnsThese context .
675− hunreify
67631
32+-- | A special context used in the construction of 'Rel8.Projection's.
33+type Field :: Type -> K.Context
34+newtype Field table a = Field (HField (Columns table) a)
67735
678−stoColumnsThese :: (Table (Reify context) a, Table (Reify context) b)
679− => SContext context
680− -> AHThese context a b
681− -> HTheseTable (Columns a) (Columns b) (Col (Reify context))
682−stoColumnsThese = \case
683− SAggregate ->
684− hreify .
685− toColumns .
686− bimap (hunreify . toColumns) (hunreify . toColumns) .
687− (\(AHThese a) -> a)
688− SExpr ->
689− hreify .
690− toColumns .
691− bimap (hunreify . toColumns) (hunreify . toColumns) .
692− (\(AHThese a) -> a)
693− SResult ->
694− hreify .
695− toColumns .
696− bimap (hunreify . toColumns) (hunreify . toColumns) .
697− (\(AHThese a) -> a)
698− SInsert ->
699− hreify .
700− toColumns .
701− bimap (hunreify . toColumns) (hunreify . toColumns) .
702− (\(AHThese a) -> a)
703− SName ->
704− hreify .
705− toColumns .
706− bimap (hunreify . toColumns) (hunreify . toColumns) .
707− (\(AHThese a) -> a)
708− SReify context ->
709− hreify .
710− stoColumnsThese context .
711− sbimapThese context (hunreify . toColumns) (hunreify . toColumns) .
712− (\(AHThese a) -> a)
71336
37+instance Sql DBType a => Table (Field table) (Field table a) where
38+ type Columns (Field table a) = HIdentity a
39+ type Context (Field table a) = Field table
40+ type FromExprs (Field table a) = a
41+ type Transpose to (Field table a) = to a
71442
715−hreify :: HTable t => t (Col context) -> t (Col (Reify context))
716−hreify a = htabulate $ \field -> Reify (hfield a field)
43+ toColumns = HIdentity
44+ fromColumns (HIdentity a) = a
45+ toResult a = HIdentity (Identity a)
46+ fromResult (HIdentity (Identity a)) = a
71747
71848
719−hunreify :: HTable t => t (Col (Reify context)) -> t (Col context)
720−hunreify a = htabulate $ \field -> case hfield a field of
721− Reify x -> x
49+fields :: Transposes context (Field table) table fields => fields
50+fields = fromColumns $ htabulate Field
src/Rel8/Schema/Generic.hsdeleted−150
@@ -1,150 +0,0 @@
1−{-# language DataKinds #-}
2−{-# language DefaultSignatures #-}
3−{-# language FlexibleContexts #-}
4−{-# language FlexibleInstances #-}
5−{-# language MultiParamTypeClasses #-}
6−{-# language ScopedTypeVariables #-}
7−{-# language StandaloneKindSignatures #-}
8−{-# language TypeApplications #-}
9−{-# language TypeFamilies #-}
10−{-# language UndecidableInstances #-}
11−
12−{-# options_ghc -fno-warn-orphans #-}
13−
14−module Rel8.Schema.Generic
15− ( Rel8able
16− , KRel8able
17− )
18−where
19−
20−-- base
21−import Data.Kind ( Constraint, Type )
22−import GHC.Generics ( Generic, Rep, from, to )
23−import Prelude
24−import Unsafe.Coerce ( unsafeCoerce )
25−
26−-- rel8
27−import Rel8.Generic.Record ( Record(..) )
28−import Rel8.Generic.Table
29− ( GTable, GColumns, fromGColumns, toGColumns
30− )
31−import Rel8.Schema.Context ( Col )
32−import Rel8.Schema.Context.Label ( Labelable )
33−import Rel8.Schema.Field ( Reify, Reifiable, hreify, hunreify )
34−import Rel8.Schema.HTable ( HTable )
35−import qualified Rel8.Schema.Kind as K
36−import Rel8.Schema.Name ( Name )
37−import Rel8.Table
38− ( Table, Columns, Context, fromColumns, toColumns
39− , TTable, TColumns
40− )
41−
42−
43−instance
44− ( Rel8able t
45− , Labelable context
46− , Reifiable context
47− ) => Table context (t context)
48− where
49− type Columns (t context) = GRep t
50− type Context (t context) = context
51−
52− fromColumns = unreify . gfromColumns . hreify
53− toColumns = hunreify . gtoColumns . reify
54−
55−
56−type KRel8able :: Type
57−type KRel8able = K.Table
58−
59−
60−-- | This type class allows you to define custom 'Table's using higher-kinded
61−-- data types. Higher-kinded data types are data types of the pattern:
62−--
63−-- @
64−-- data MyType f =
65−-- MyType { field1 :: Column f T1 OR HK1 f
66−-- , field2 :: Column f T2 OR HK2 f
67−-- , ...
68−-- , fieldN :: Column f Tn OR HKn f
69−-- }
70−-- @
71−--
72−-- where @Tn@ is any Haskell type, and @HKn@ is any higher-kinded type.
73−--
74−-- That is, higher-kinded data are records where all fields in the record are
75−-- all either of the type @Column f T@ (for any @T@), or are themselves
76−-- higher-kinded data:
77−--
78−-- [Nested]
79−--
80−-- @
81−-- data Nested f =
82−-- Nested { nested1 :: MyType f
83−-- , nested2 :: MyType f
84−-- }
85−-- @
86−--
87−-- The @Rel8able@ type class is used to give us a special mapping operation
88−-- that lets us change the type parameter @f@.
89−--
90−-- [Supplying @Rel8able@ instances]
91−--
92−-- This type class should be derived generically for all table types in your
93−-- project. To do this, enable the @DeriveAnyType@ and @DeriveGeneric@ language
94−-- extensions:
95−--
96−-- @
97−-- \{\-\# LANGUAGE DeriveAnyClass, DeriveGeneric #-\}
98−--
99−-- data MyType f = MyType { fieldA :: Column f T }
100−-- deriving ( GHC.Generics.Generic, Rel8able )
101−-- @
102−type Rel8able :: KRel8able -> Constraint
103−class HTable (GRep t) => Rel8able t where
104− type GRep t :: K.HTable
105−
106− gfromColumns :: (Labelable context, Reifiable context)
107− => GRep t (Col (Reify context)) -> t (Reify context)
108−
109− gtoColumns :: (Labelable context, Reifiable context)
110− => t (Reify context) -> GRep t (Col (Reify context))
111−
112− type GRep t = GColumns TColumns (Rep (Record (t (Reify Name))))
113−
114− default gfromColumns :: forall context.
115− ( Generic (Record (t (Reify context)))
116− , GColumns TColumns (Rep (Record (t (Reify context)))) ~ GRep t
117− , GTable (TTable (Reify context)) TColumns (Col (Reify context)) (Rep (Record (t (Reify context))))
118− )
119− => GRep t (Col (Reify context)) -> t (Reify context)
120− gfromColumns =
121− unrecord .
122− to .
123− fromGColumns @(TTable (Reify context)) @TColumns fromColumns
124−
125− default gtoColumns :: forall context.
126− ( Generic (Record (t (Reify context)))
127− , GColumns TColumns (Rep (Record (t (Reify context)))) ~ GRep t
128− , GTable (TTable (Reify context)) TColumns (Col (Reify context)) (Rep (Record (t (Reify context))))
129− )
130− => t (Reify context) -> GRep t (Col (Reify context))
131− gtoColumns =
132− toGColumns @(TTable (Reify context)) @TColumns toColumns .
133− from .
134− Record
135−
136−
137−reify ::
138− (-- Rel8able t
139− --, forall necessity a. Coercible (Field context necessity a) (AField context necessity a) => Coercible (t context) (t (Reify context))
140− )
141− => t context -> t (Reify context)
142−reify = unsafeCoerce
143−
144−
145−unreify ::
146− (-- Rel8able t
147− --, forall necessity a. Coercible (AField context necessity a) (Field context necessity a) => Coercible (t (Reify context)) (t context)
148− )
149− => t (Reify context) -> t context
150−unreify = unsafeCoerce
src/Rel8/Schema/HKD.hsdeleted−303
@@ -1,303 +0,0 @@
1−{-# language AllowAmbiguousTypes #-}
2−{-# language BlockArguments #-}
3−{-# language ConstraintKinds #-}
4−{-# language DataKinds #-}
5−{-# language FlexibleContexts #-}
6−{-# language FlexibleInstances #-}
7−{-# language FunctionalDependencies #-}
8−{-# language GADTs #-}
9−{-# language LambdaCase #-}
10−{-# language QuantifiedConstraints #-}
11−{-# language PolyKinds #-}
12−{-# language RankNTypes #-}
13−{-# language ScopedTypeVariables #-}
14−{-# language StandaloneKindSignatures #-}
15−{-# language TypeApplications #-}
16−{-# language TypeFamilyDependencies #-}
17−{-# language TypeOperators #-}
18−{-# language UndecidableInstances #-}
19−{-# language UndecidableSuperClasses #-}
20−
21−{-# options -Wno-orphans #-}
22−
23−module Rel8.Schema.HKD
24− ( Lift
25− , HKDT(..)
26− ) where
27−
28−-- base
29−import Data.Functor.Compose ( Compose(..) )
30−import Data.Functor.Identity ( Identity(..), runIdentity )
31−import Data.Kind ( Constraint, Type )
32−import GHC.Generics
33− ( (:*:)( (:*:) ), K1( K1 ), M1( M1 ), C, D, S, Meta( MetaSel )
34− , Rep
35− )
36−import GHC.TypeLits ( KnownSymbol )
37−import Prelude
38−
39−-- higgledy
40−import Data.Generic.HKD ( Construct, HKD( HKD, runHKD ), GHKD_, construct, deconstruct )
41−
42−-- rel8
43−import Rel8.Aggregate ( Col(..), Aggregate )
44−import Rel8.Expr ( Expr )
45−import Rel8.Schema.Context.Label
46− ( Labelable
47− , HLabelable, hlabeler, hunlabeler
48− )
49−import Rel8.Schema.Dict ( Dict( Dict ) )
50−import Rel8.Schema.Field ( Reify, Reifiable(..), SContext(..), hunreify, hreify )
51−import Rel8.Schema.HTable ( HTable )
52−import Rel8.Schema.HTable.Label ( HLabel, hlabel, hunlabel )
53−import Rel8.Schema.HTable.Product ( HProduct( HProduct ) )
54−import Rel8.Schema.HTable.Type ( HType( HType ) )
55−import Rel8.Schema.Insert ( Insert, Col(..) )
56−import qualified Rel8.Schema.Kind as K
57−import Rel8.Schema.Name ( Name(..) )
58−import Rel8.Schema.Null ( Sql )
59−import Rel8.Schema.Result ( Result )
60−import Rel8.Table ( Table, Columns, Context, fromColumns, toColumns )
61−import Rel8.Table.Recontextualize ( Recontextualize )
62−import Rel8.Table.Serialize ( FromExprs, ToExprs, fromResult, toResult )
63−import Rel8.Type ( DBType )
64−
65−
66−type Column1Helper :: K.Context -> (Type -> Type) -> Type -> Constraint
67−class
68− ( Table context (f a)
69− , Context1 f ~ context
70− , Context (f a) ~ context
71− , Columns (f a) ~ HType a
72− )
73− => Column1Helper context f a | f -> context
74−instance
75− ( Table context (f a)
76− , Context1 f ~ context
77− , Context (f a) ~ context
78− , Columns (f a) ~ HType a
79− )
80− => Column1Helper context f a
81−
82−
83−type Column1 :: K.Context -> (Type -> Type) -> Constraint
84−class
85− ( forall a. Sql DBType a => Column1Helper context f a
86− , Context1 f ~ context
87− ) =>
88− Column1 context f | f -> context
89−instance
90− ( forall a. Sql DBType a => Column1Helper context f a
91− , Context1 f ~ context
92− ) =>
93− Column1 context f
94−
95−
96−type Context1 :: (Type -> Type) -> K.Context
97−type Context1 f = Context (f Bool)
98−
99−
100−toColumn1 :: forall a f context. (Column1 context f, Sql DBType a)
101− => f a -> HType a (Col context)
102−toColumn1 = case Dict @(Column1Helper context f) @a of
103− Dict -> toColumns
104−
105−
106−fromColumn1 :: forall a f context. (Column1 context f, Sql DBType a)
107− => HType a (Col context) -> f a
108−fromColumn1 = case Dict @(Column1Helper context f) @a of
109− Dict -> fromColumns
110−
111−
112−type Recontextualize1
113− :: K.Context
114− -> K.Context
115− -> (Type -> Type)
116− -> (Type -> Type)
117− -> Constraint
118−class Recontextualize context context' (f Bool) (f' Bool) =>
119− Recontextualize1 context context' f f'
120−instance Recontextualize context context' (f Bool) (f' Bool) =>
121− Recontextualize1 context context' f f'
122−
123−
124−class HTable (GColumns rep) => GTable rep where
125− toGColumns :: HLabelable context
126− => (forall a. Sql DBType a => f a -> HType a context)
127− -> GHKD_ f rep x
128− -> GColumns rep context
129− fromGColumns :: HLabelable context
130− => (forall a. Sql DBType a => HType a context -> f a)
131− -> GColumns rep context
132− -> GHKD_ f rep x
133−
134−
135−instance GTable rep => GTable (M1 D c rep) where
136− toGColumns f (M1 a) = toGColumns f a
137− {-# INLINABLE toGColumns #-}
138−
139− fromGColumns f = M1 . fromGColumns f
140− {-# INLINABLE fromGColumns #-}
141−
142−
143−instance GTable rep => GTable (M1 C c rep) where
144− toGColumns f (M1 a) = toGColumns f a
145− {-# INLINABLE toGColumns #-}
146−
147− fromGColumns f = M1 . fromGColumns f
148− {-# INLINABLE fromGColumns #-}
149−
150−
151−instance (KnownSymbol name, Sql DBType a) =>
152− GTable (M1 S ('MetaSel ('Just name) _su _ss _ds) (K1 i a))
153− where
154− toGColumns f (M1 (K1 a)) = hlabel hlabeler (f a)
155− {-# INLINABLE toGColumns #-}
156−
157− fromGColumns f a = M1 (K1 (f (hunlabel hunlabeler a)))
158− {-# INLINABLE fromGColumns #-}
159−
160−
161−instance (GTable f, GTable g) => GTable (f :*: g) where
162− toGColumns f (x :*: y) = HProduct (toGColumns f x) (toGColumns f y)
163− {-# INLINABLE toGColumns #-}
164−
165− fromGColumns f (HProduct x y) = fromGColumns f x :*: fromGColumns f y
166− {-# INLINABLE fromGColumns #-}
167−
168−
169−type GRep a = GColumns (Rep a)
170−
171−
172−type GColumns :: (Type -> Type) -> K.HTable
173−type family GColumns rep where
174− GColumns (M1 D _ f) = GColumns f
175− GColumns (M1 C _ f) = GColumns f
176− GColumns (M1 S ('MetaSel ('Just name) _ _ _) (K1 _ a)) =
177− HLabel name (HType a)
178− GColumns (f :*: g) = HProduct (GColumns f) (GColumns g)
179−
180−
181−instance (GTable (Rep a), Column1 context f, Labelable context) =>
182− Table context (HKD a f)
183− where
184− type Columns (HKD a f) = GRep a
185− type Context (HKD a f) = Context1 f
186−
187− toColumns = toGColumns toColumn1 . runHKD
188− fromColumns = HKD . fromGColumns fromColumn1
189−
190−
191−instance
192− ( a ~ a'
193− , GTable (Rep a)
194− , Recontextualize1 context context' f f'
195− , Column1 context f, Labelable context
196− , Column1 context' f', Labelable context'
197− ) =>
198− Recontextualize
199− context
200− context'
201− (HKD a f)
202− (HKD a' f')
203−
204−
205−type Lift :: K.Context -> Type -> Type
206−type family Lift context a where
207− Lift (Reify context) a = ALift context a
208− Lift Aggregate a = HKD a (Compose Aggregate Expr)
209− Lift Expr a = HKD a Expr
210− Lift Insert a = HKD a Expr
211− Lift Name a = HKD a Name
212− Lift Result a = a
213−
214−
215−type ALift :: K.Context -> Type -> Type
216−newtype ALift context a = ALift
217− { unALift :: Lift context a
218− }
219−
220−
221−instance
222− ( Reifiable context
223− , GTable (Rep a)
224− , Construct Identity a
225− )
226− => Table (Reify context) (ALift context a)
227− where
228− type Context (ALift context a) = Reify context
229− type Columns (ALift context a) = GRep a
230−
231− fromColumns = sfromColumnsLift contextSing
232− toColumns = stoColumnsLift contextSing
233−
234−
235−instance
236− ( Reifiable context
237− , Reifiable context'
238− , GTable (Rep a)
239− , Construct Identity a
240− )
241− => Recontextualize
242− (Reify context)
243− (Reify context')
244− (ALift context a)
245− (ALift context' a)
246−
247−
248−sfromColumnsLift :: forall a context. (GTable (Rep a), Construct Identity a)
249− => SContext context
250− -> GRep a (Col (Reify context))
251− -> ALift context a
252−sfromColumnsLift = \case
253− SAggregate ->
254− ALift .
255− HKD .
256− fromGColumns (\(HType (Aggregation a)) -> Compose a) .
257− hunreify
258− SExpr -> ALift . fromColumns . hunreify
259− SInsert ->
260− ALift .
261− HKD .
262− fromGColumns (\(HType (RequiredInsert a)) -> a) .
263− hunreify
264− SName -> ALift . fromColumns . hunreify
265− SResult -> ALift . runIdentity . construct . fromColumns . hunreify
266− SReify context -> ALift . sfromColumnsLift context . hunreify
267−
268−
269−stoColumnsLift :: forall a context. (GTable (Rep a), Construct Identity a)
270− => SContext context
271− -> ALift context a
272− -> GRep a (Col (Reify context))
273−stoColumnsLift = \case
274− SAggregate ->
275− hreify .
276− toGColumns (\(Compose a) -> HType (Aggregation a)) .
277− runHKD .
278− unALift
279− SExpr -> hreify . toColumns . unALift
280− SInsert ->
281− hreify .
282− toGColumns (HType . RequiredInsert) .
283− runHKD .
284− unALift
285− SName -> hreify . toColumns . unALift
286− SResult -> hreify . toColumns . deconstruct @Identity . unALift
287− SReify context -> hreify . stoColumnsLift context . unALift
288−
289−
290−type HKDT :: Type -> Type
291−newtype HKDT a = HKDT
292− { unHKDT :: a
293− }
294−
295−
296−instance (GTable (Rep a), Construct Identity a, x ~ HKD a Expr) =>
297− ToExprs x (HKDT a)
298− where
299− toResult = toColumns . deconstruct @Identity . unHKDT
300− fromResult = HKDT . runIdentity . construct . fromColumns
301−
302−
303−type instance FromExprs (HKD a Expr) = a
src/Rel8/Schema/HTable.hs+55−23
@@ -16,11 +16,12 @@
1616module Rel8.Schema.HTable
1717 ( HTable (HField, HConstrainTable)
1818 , hfield, htabulate, htraverse, hdicts, hspecs
19− , htabulateA
19+ , hfoldMap, hmap, htabulateA, htraverseP, htraversePWithField
2020 )
2121where
2222
2323-- base
24+import Data.Functor.Const ( Const( Const ), getConst )
2425import Data.Kind ( Constraint, Type )
2526import Data.Functor.Compose ( Compose( Compose ), getCompose )
2627import Data.Proxy ( Proxy )
@@ -32,16 +33,21 @@ import GHC.Generics
3233 )
3334import Prelude
3435
36+-- profunctors
37+import Data.Profunctor ( rmap, Profunctor (lmap) )
38+
39+-- product-profunctors
40+import Data.Profunctor.Product ( ProductProfunctor ((****)) )
41+
3542-- rel8
3643import Rel8.Schema.Dict ( Dict )
37−import Rel8.Schema.Spec ( Spec, SSpec )
44+import Rel8.Schema.Spec ( Spec )
3845import Rel8.Schema.HTable.Product ( HProduct( HProduct ) )
3946import qualified Rel8.Schema.Kind as K
4047
4148-- semigroupoids
4249import Data.Functor.Apply ( Apply, (<.>) )
4350
44−
4551-- | A @HTable@ is a functor-indexed/higher-kinded data type that is
4652-- representable ('htabulate'/'hfield'), constrainable ('hdicts'), and
4753-- specified ('hspecs').
@@ -50,14 +56,14 @@ import Data.Functor.Apply ( Apply, (<.>) )
5056-- instances yourself or specify this constraint.
5157type HTable :: K.HTable -> Constraint
5258class HTable t where
53− type HField t = (field :: Spec -> Type) | field -> t
54− type HConstrainTable t (c :: Spec -> Constraint) :: Constraint
59+ type HField t = (field :: Type -> Type) | field -> t
60+ type HConstrainTable t (c :: Type -> Constraint) :: Constraint
5561
56− hfield :: t context -> HField t spec -> context spec
57− htabulate :: (forall spec. HField t spec -> context spec) -> t context
58− htraverse :: Apply m => (forall spec. f spec -> m (g spec)) -> t f -> m (t g)
62+ hfield :: t context -> HField t a -> context a
63+ htabulate :: (forall a. HField t a -> context a) -> t context
64+ htraverse :: Apply m => (forall a. f a -> m (g a)) -> t f -> m (t g)
5965 hdicts :: HConstrainTable t c => t (Dict c)
60− hspecs :: t SSpec
66+ hspecs :: t Spec
6167
6268 type HField t = GHField t
6369 type HConstrainTable t c = HConstrainTable (GHColumns (Rep (t Proxy))) c
@@ -68,7 +74,7 @@ class HTable t where
6874 , HField (GHColumns (Rep (t Proxy))) ~ HField (GHColumns (Rep (t context)))
6975 , GHTable context (Rep (t context))
7076 )
71− => t context -> HField t spec -> context spec
77+ => t context -> HField t a -> context a
7278 hfield table (GHField field) = hfield (toGHColumns (from table)) field
7379
7480 default htabulate ::
@@ -77,7 +83,7 @@ class HTable t where
7783 , HField (GHColumns (Rep (t Proxy))) ~ HField (GHColumns (Rep (t context)))
7884 , GHTable context (Rep (t context))
7985 )
80− => (forall spec. HField t spec -> context spec) -> t context
86+ => (forall a. HField t a -> context a) -> t context
8187 htabulate f = to $ fromGHColumns $ htabulate (f . GHField)
8288
8389 default htraverse
@@ -87,7 +93,7 @@ class HTable t where
8793 , Generic (t g), GHTable g (Rep (t g))
8894 , GHColumns (Rep (t f)) ~ GHColumns (Rep (t g))
8995 )
90− => (forall spec. f spec -> m (g spec)) -> t f -> m (t g)
96+ => (forall a. f a -> m (g a)) -> t f -> m (t g)
9197 htraverse f = fmap (to . fromGHColumns) . htraverse f . toGHColumns . from
9298
9399 default hdicts
@@ -101,10 +107,10 @@ class HTable t where
101107 hdicts = to $ fromGHColumns (hdicts @(GHColumns (Rep (t Proxy))) @c)
102108
103109 default hspecs ::
104− ( Generic (t SSpec)
105− , GHTable SSpec (Rep (t SSpec))
110+ ( Generic (t Spec)
111+ , GHTable Spec (Rep (t Spec))
106112 )
107− => t SSpec
113+ => t Spec
108114 hspecs = to $ fromGHColumns hspecs
109115
110116 {-# INLINABLE hfield #-}
@@ -114,17 +120,43 @@ class HTable t where
114120 {-# INLINABLE hspecs #-}
115121
116122
123+hfoldMap :: (HTable t, Semigroup s)
124+ => (forall a. context a -> s) -> t context -> s
125+hfoldMap f a = getConst $ htraverse (Const . f) a
126+
127+
128+hmap :: HTable t
129+ => (forall a. context a -> context' a) -> t context -> t context'
130+hmap f a = htabulate $ \field -> f (hfield a field)
131+
132+
117133htabulateA :: (HTable t, Apply m)
118− => (forall spec. HField t spec -> m (context spec)) -> m (t context)
134+ => (forall a. HField t a -> m (context a)) -> m (t context)
119135htabulateA f = htraverse getCompose $ htabulate $ Compose . f
120136{-# INLINABLE htabulateA #-}
121137
138+newtype ApplyP p a b = ApplyP { unApplyP :: p a b }
139+
140+instance Profunctor p => Functor (ApplyP p a) where
141+ fmap f = ApplyP . rmap f . unApplyP
142+
143+instance ProductProfunctor p => Apply (ApplyP p a) where
144+ ApplyP f <.> ApplyP x = ApplyP (rmap id f **** x)
145+
146+htraverseP :: (HTable t, ProductProfunctor p)
147+ => (forall a. p (f a) (g a)) -> p (t f) (t g)
148+htraverseP f = htraversePWithField (const f)
149+
150+htraversePWithField :: (HTable t, ProductProfunctor p)
151+ => (forall a. HField t a -> p (f a) (g a)) -> p (t f) (t g)
152+htraversePWithField f = unApplyP $ htabulateA $ \field -> ApplyP $
153+ lmap (flip hfield field) (f field)
122154
123−type GHField :: K.HTable -> Spec -> Type
124−newtype GHField t spec = GHField (HField (GHColumns (Rep (t Proxy))) spec)
155+type GHField :: K.HTable -> Type -> Type
156+newtype GHField t a = GHField (HField (GHColumns (Rep (t Proxy))) a)
125157
126158
127−type GHTable :: K.HContext -> (Type -> Type) -> Constraint
159+type GHTable :: K.Context -> (Type -> Type) -> Constraint
128160class HTable (GHColumns rep) => GHTable context rep | rep -> context where
129161 type GHColumns rep :: K.HTable
130162 toGHColumns :: rep x -> GHColumns rep context
@@ -150,10 +182,10 @@ instance (GHTable context a, GHTable context b) => GHTable context (a :*: b) whe
150182
151183
152184-- | A HField type for indexing into HProduct.
153−type HProductField :: K.HTable -> K.HTable -> Spec -> Type
154−data HProductField x y spec
155− = HFst (HField x spec)
156− | HSnd (HField y spec)
185+type HProductField :: K.HTable -> K.HTable -> Type -> Type
186+data HProductField x y a
187+ = HFst (HField x a)
188+ | HSnd (HField y a)
157189
158190
159191instance (HTable x, HTable y) => HTable (HProduct x y) where
src/Rel8/Schema/HTable/Either.hs+2−4
@@ -14,19 +14,17 @@ import GHC.Generics ( Generic )
1414import Prelude ()
1515
1616-- rel8
17−import Rel8.Kind.Necessity ( Necessity( Required ) )
1817import Rel8.Schema.HTable ( HTable )
19−import Rel8.Schema.HTable.Identity ( HIdentity(..) )
18+import Rel8.Schema.HTable.Identity ( HIdentity )
2019import Rel8.Schema.HTable.Label ( HLabel )
2120import Rel8.Schema.HTable.Nullify ( HNullify )
2221import qualified Rel8.Schema.Kind as K
23−import Rel8.Schema.Spec ( Spec( Spec ) )
2422import Rel8.Type.Tag ( EitherTag )
2523
2624
2725type HEitherTable :: K.HTable -> K.HTable -> K.HTable
2826data HEitherTable left right context = HEitherTable
29− { htag :: HIdentity ('Spec '["isRight"] 'Required EitherTag) context
27+ { htag :: HLabel "isRight" (HIdentity EitherTag) context
3028 , hleft :: HLabel "Left" (HNullify left) context
3129 , hright :: HLabel "Right" (HNullify right) context
3230 }
src/Rel8/Schema/HTable/Identity.hs+16−17
@@ -1,15 +1,17 @@
11{-# language DataKinds #-}
2−{-# language GADTs #-}
2+{-# language FlexibleContexts #-}
33{-# language StandaloneKindSignatures #-}
44{-# language TypeFamilies #-}
5+{-# language UndecidableInstances #-}
56
67module Rel8.Schema.HTable.Identity
7− ( HIdentity(..)
8+ ( HIdentity( HIdentity, unHIdentity )
89 )
910where
1011
1112-- base
1213import Data.Kind ( Type )
14+import Data.Type.Equality ( (:~:)( Refl ) )
1315import Prelude
1416
1517-- rel8
@@ -19,26 +21,23 @@ import Rel8.Schema.HTable
1921 , hfield, htabulate, htraverse, hdicts, hspecs
2022 )
2123import qualified Rel8.Schema.Kind as K
22−import Rel8.Schema.Spec ( Spec, KnownSpec, specSing )
24+import Rel8.Schema.Null ( Sql )
25+import Rel8.Schema.Spec ( specification )
26+import Rel8.Type ( DBType )
2327
2428
25−type HIdentity :: Spec -> K.HTable
26−newtype HIdentity spec context = HIdentity
27− { unHIdentity :: context spec
29+type HIdentity :: Type -> K.HTable
30+newtype HIdentity a context = HIdentity
31+ { unHIdentity :: context a
2832 }
2933
3034
31−type HIdentityField :: Spec -> Spec -> Type
32−data HIdentityField _spec spec where
33− HIdentityField :: HIdentityField spec spec
35+instance Sql DBType a => HTable (HIdentity a) where
36+ type HConstrainTable (HIdentity a) constraint = constraint a
37+ type HField (HIdentity a) = (:~:) a
3438
35−
36−instance KnownSpec spec => HTable (HIdentity spec) where
37− type HConstrainTable (HIdentity spec) c = c spec
38− type HField (HIdentity spec) = HIdentityField spec
39−
40− hfield (HIdentity a) HIdentityField = a
41− htabulate f = HIdentity $ f HIdentityField
39+ hfield (HIdentity a) Refl = a
40+ htabulate f = HIdentity $ f Refl
4241 htraverse f (HIdentity a) = HIdentity <$> f a
4342 hdicts = HIdentity Dict
44− hspecs = HIdentity specSing
43+ hspecs = HIdentity specification
src/Rel8/Schema/HTable/Label.hs+37−50
@@ -1,83 +1,70 @@
1−{-# LANGUAGE DeriveAnyClass #-}
2−{-# LANGUAGE DeriveGeneric #-}
3−{-# LANGUAGE DerivingStrategies #-}
4−{-# LANGUAGE LambdaCase #-}
5−{-# language ConstraintKinds #-}
61{-# language DataKinds #-}
7−{-# language FlexibleInstances #-}
8−{-# language GADTs #-}
9−{-# language MultiParamTypeClasses #-}
10−{-# language QuantifiedConstraints #-}
112{-# language RankNTypes #-}
123{-# language RecordWildCards #-}
134{-# language ScopedTypeVariables #-}
145{-# language StandaloneKindSignatures #-}
6+{-# language TypeApplications #-}
157{-# language TypeFamilies #-}
16−{-# language TypeOperators #-}
17−{-# language UndecidableInstances #-}
188
199module Rel8.Schema.HTable.Label
20− ( HLabel, Label
21− , hlabel, hunlabel
10+ ( HLabel, hlabel, hrelabel, hunlabel
11+ , hproject
2212 )
2313where
2414
2515-- base
16+import Data.Kind ( Type )
2617import Data.Proxy ( Proxy( Proxy ) )
27−import GHC.TypeLits ( KnownSymbol, Symbol )
18+import GHC.TypeLits ( KnownSymbol, Symbol, symbolVal )
2819import Prelude
2920
3021-- rel8
31−import Rel8.Kind.Labels ( SLabels( SLabels ) )
3222import Rel8.Schema.HTable
33− ( HTable
34− , hfield, htabulate, hspecs
23+ ( HTable, HConstrainTable, HField
24+ , htabulate, hfield, htraverse, hdicts, hspecs
3525 )
3626import qualified Rel8.Schema.Kind as K
37−import Rel8.Schema.Spec ( Spec( Spec ), SSpec(..) )
38−import Rel8.FCF
39−import Rel8.Schema.HTable.MapTable
40−import GHC.Generics (Generic)
27+import Rel8.Schema.Spec ( Spec(..) )
4128
4229
4330type HLabel :: Symbol -> K.HTable -> K.HTable
44−newtype HLabel label table context = HLabel (HMapTable (Label label) table context)
45− deriving stock Generic
46− deriving anyclass HTable
31+newtype HLabel label table context = HLabel (table context)
4732
4833
49−data Label :: Symbol -> Spec -> Exp Spec
34+type HLabelField :: Symbol -> K.HTable -> Type -> Type
35+newtype HLabelField label table a = HLabelField (HField table a)
5036
5137
52−type instance Eval (Label label ('Spec labels necessity a)) = 'Spec (label : labels) necessity a
38+instance (HTable table, KnownSymbol label) => HTable (HLabel label table) where
39+ type HField (HLabel label table) = HLabelField label table
40+ type HConstrainTable (HLabel label table) constraint =
41+ HConstrainTable table constraint
5342
43+ hfield (HLabel a) (HLabelField field) = hfield a field
44+ htabulate f = HLabel (htabulate (f . HLabelField))
45+ htraverse f (HLabel a) = HLabel <$> htraverse f a
46+ hdicts = HLabel (hdicts @table)
47+ hspecs = HLabel $ htabulate $ \field -> case hfield (hspecs @table) field of
48+ Spec {..} -> Spec {labels = symbolVal (Proxy @label) : labels, ..}
49+ {-# INLINABLE hspecs #-}
5450
55−instance KnownSymbol l => MapSpec (Label l) where
56− mapInfo = \case
57− SSpec {..} -> SSpec {labels = SLabels Proxy labels, ..}
5851
59−
60−hlabel :: (HTable t, KnownSymbol label)
61− => (forall labels necessity a. ()
62− => context ('Spec labels necessity a)
63− -> context ('Spec (label ': labels) necessity a))
64− -> t context
65− -> HLabel label t context
66−hlabel labeler a = HLabel $ htabulate $ \(HMapTableField field) ->
67− case hfield hspecs field of
68− SSpec {} -> labeler (hfield a field)
52+hlabel :: forall label t context. t context -> HLabel label t context
53+hlabel = HLabel
6954{-# INLINABLE hlabel #-}
7055
7156
72−hunlabel :: (HTable t, KnownSymbol label)
73− => (forall labels necessity a. ()
74− => context ('Spec (label ': labels) necessity a)
75− -> context ('Spec labels necessity a))
76− -> HLabel label t context
77− -> t context
78−hunlabel unlabler (HLabel as) =
79− htabulate $ \field ->
80− case hfield hspecs field of
81− SSpec {} -> case hfield as (HMapTableField field) of
82− a -> unlabler a
57+hrelabel :: forall label' label t context. HLabel label t context -> HLabel label' t context
58+hrelabel = hlabel . hunlabel
59+{-# INLINABLE hrelabel #-}
60+
61+
62+hunlabel :: forall label t context. HLabel label t context -> t context
63+hunlabel (HLabel a) = a
8364{-# INLINABLE hunlabel #-}
65+
66+
67+hproject :: ()
68+ => (forall ctx. t ctx -> t' ctx)
69+ -> HLabel label t context -> HLabel label t' context
70+hproject f (HLabel a) = HLabel (f a)
src/Rel8/Schema/HTable/MapTable.hs+22−12
@@ -6,7 +6,7 @@
66{-# language GADTs #-}
77{-# language InstanceSigs #-}
88{-# language MultiParamTypeClasses #-}
9−{-# language PolyKinds #-}
9+{-# language RankNTypes #-}
1010{-# language ScopedTypeVariables #-}
1111{-# language StandaloneKindSignatures #-}
1212{-# language TypeApplications #-}
@@ -19,34 +19,38 @@ module Rel8.Schema.HTable.MapTable
1919 , MapSpec(..)
2020 , Precompose(..)
2121 , HMapTableField(..)
22+ , hproject
2223 )
2324where
2425
2526-- base
2627import Data.Kind ( Constraint, Type )
27−import Prelude ( ($), (.), (<$>), fmap )
28+import Prelude
2829
2930-- rel8
30−import Rel8.FCF
31+import Rel8.FCF ( Exp, Eval )
3132import Rel8.Schema.HTable
32−import Rel8.Schema.Spec ( Spec, SSpec )
33+ ( HTable, HConstrainTable, HField
34+ , hfield, htabulate, htraverse, hdicts, hspecs
35+ )
36+import Rel8.Schema.Spec ( Spec )
3337import qualified Rel8.Schema.Kind as K
3438import Rel8.Schema.Dict ( Dict( Dict ) )
3539
3640
37−type HMapTable :: (a -> Exp b) -> ((a -> Type) -> Type) -> (b -> Type) -> Type
38−newtype HMapTable f t g = HMapTable
39− { unHMapTable :: t (Precompose f g)
41+type HMapTable :: (Type -> Exp Type) -> K.HTable -> K.HTable
42+newtype HMapTable f t context = HMapTable
43+ { unHMapTable :: t (Precompose f context)
4044 }
4145
4246
43−type Precompose :: (a -> Exp b) -> (b -> Type) -> a -> Type
47+type Precompose :: (Type -> Exp Type) -> K.Context -> K.Context
4448newtype Precompose f g x = Precompose
4549 { precomposed :: g (Eval (f x))
4650 }
4751
4852
49−type HMapTableField :: (Spec -> Exp a) -> K.HTable -> a -> Type
53+type HMapTableField :: (Type -> Exp Type) -> K.HTable -> K.Context
5054data HMapTableField f t x where
5155 HMapTableField :: HField t a -> HMapTableField f t (Eval (f a))
5256
@@ -79,11 +83,17 @@ instance (HTable t, MapSpec f) => HTable (HMapTable f t) where
7983 {-# INLINABLE hspecs #-}
8084
8185
82−type MapSpec :: (Spec -> Exp Spec) -> Constraint
86+type MapSpec :: (Type -> Exp Type) -> Constraint
8387class MapSpec f where
84− mapInfo :: SSpec x -> SSpec (Eval (f x))
88+ mapInfo :: Spec x -> Spec (Eval (f x))
8589
8690
87−type ComposeConstraint :: (a -> Exp b) -> (b -> Constraint) -> a -> Constraint
91+type ComposeConstraint :: (Type -> Exp Type) -> (Type -> Constraint) -> Type -> Constraint
8892class c (Eval (f a)) => ComposeConstraint f c a
8993instance c (Eval (f a)) => ComposeConstraint f c a
94+
95+
96+hproject :: ()
97+ => (forall ctx. t ctx -> t' ctx)
98+ -> HMapTable f t context -> HMapTable f t' context
99+hproject f (HMapTable a) = HMapTable (f a)
src/Rel8/Schema/HTable/Maybe.hs+2−4
@@ -14,19 +14,17 @@ import GHC.Generics ( Generic )
1414import Prelude
1515
1616-- rel8
17−import Rel8.Kind.Necessity ( Necessity( Required ) )
1817import Rel8.Schema.HTable ( HTable )
19−import Rel8.Schema.HTable.Identity ( HIdentity(..) )
18+import Rel8.Schema.HTable.Identity ( HIdentity )
2019import Rel8.Schema.HTable.Label ( HLabel )
2120import Rel8.Schema.HTable.Nullify ( HNullify )
2221import qualified Rel8.Schema.Kind as K
23−import Rel8.Schema.Spec ( Spec( Spec ) )
2422import Rel8.Type.Tag ( MaybeTag )
2523
2624
2725type HMaybeTable :: K.HTable -> K.HTable
2826data HMaybeTable table context = HMaybeTable
29− { htag :: HIdentity ('Spec '["isJust"] 'Required (Maybe MaybeTag)) context
27+ { htag :: HLabel "isJust" (HIdentity (Maybe MaybeTag)) context
3028 , hjust :: HLabel "Just" (HNullify table) context
3129 }
3230 deriving stock Generic
src/Rel8/Schema/HTable/Nullify.hs+52−37
@@ -1,15 +1,16 @@
1−{-# LANGUAGE DeriveAnyClass #-}
2−{-# LANGUAGE DerivingStrategies #-}
3−{-# LANGUAGE DeriveGeneric #-}
4−{-# LANGUAGE NamedFieldPuns #-}
5−{-# LANGUAGE LambdaCase #-}
61{-# language ConstraintKinds #-}
72{-# language DataKinds #-}
3+{-# language DeriveAnyClass #-}
4+{-# language DerivingStrategies #-}
5+{-# language DeriveGeneric #-}
86{-# language FlexibleInstances #-}
97{-# language GADTs #-}
8+{-# language LambdaCase #-}
109{-# language MultiParamTypeClasses #-}
10+{-# language NamedFieldPuns #-}
1111{-# language QuantifiedConstraints #-}
1212{-# language RankNTypes #-}
13+{-# language RecordWildCards #-}
1314{-# language ScopedTypeVariables #-}
1415{-# language StandaloneKindSignatures #-}
1516{-# language TypeFamilies #-}
@@ -18,25 +19,34 @@
1819module Rel8.Schema.HTable.Nullify
1920 ( HNullify( HNullify )
2021 , Nullify
21− , hnulls, hnullify, hunnullify
22+ , hguard
23+ , hnulls
24+ , hnullify
25+ , hunnullify
26+ , hproject
2227 )
2328where
2429
2530-- base
31+import Data.Kind ( Type )
32+import GHC.Generics ( Generic )
2633import Prelude hiding ( null )
2734
2835-- rel8
36+import Rel8.FCF ( Eval, Exp )
2937import Rel8.Schema.HTable ( HTable, hfield, htabulate, htabulateA, hspecs )
38+import Rel8.Schema.HTable.MapTable
39+ ( HMapTable, HMapTableField( HMapTableField )
40+ , MapSpec, mapInfo
41+ )
42+import qualified Rel8.Schema.HTable.MapTable as HMapTable ( hproject )
3043import qualified Rel8.Schema.Kind as K
3144import Rel8.Schema.Null ( Nullity( Null, NotNull ) )
3245import qualified Rel8.Schema.Null as Type ( Nullify )
33−import Rel8.Schema.Spec ( Spec( Spec ), SSpec(..) )
46+import Rel8.Schema.Spec ( Spec(..) )
3447
3548-- semigroupoids
3649import Data.Functor.Apply ( Apply )
37−import Rel8.Schema.HTable.MapTable
38−import Rel8.FCF
39−import GHC.Generics (Generic)
4050
4151
4252type HNullify :: K.HTable -> K.HTable
@@ -45,58 +55,63 @@ newtype HNullify table context = HNullify (HMapTable Nullify table context)
4555 deriving anyclass HTable
4656
4757
48−
49−-- | Transform a 'Spec' by allowing it to be @null@.
50−data Nullify :: Spec -> Exp Spec
51−
52−
53−type instance Eval (Nullify ('Spec labels necessity a)) =
54− 'Spec labels necessity (Type.Nullify a)
58+-- | Transform a 'Type' by allowing it to be @null@.
59+data Nullify :: Type -> Exp Type
60+type instance Eval (Nullify a) = Type.Nullify a
5561
5662
5763instance MapSpec Nullify where
5864 mapInfo = \case
59− SSpec{labels, necessity, info, nullity} -> SSpec
60− { labels
61− , necessity
62− , info
63− , nullity = case nullity of
65+ Spec {nullity, ..} -> Spec
66+ { nullity = case nullity of
6467 Null -> Null
6568 NotNull -> Null
66− }
69+ , ..
70+ }
71+
72+
73+hguard :: HTable t
74+ => (forall a. context (Maybe a) -> context (Maybe a))
75+ -> HNullify t context -> HNullify t context
76+hguard guarder (HNullify as) = HNullify $ htabulate $ \(HMapTableField field) ->
77+ case hfield hspecs field of
78+ Spec {nullity} -> case hfield as (HMapTableField field) of
79+ a -> case nullity of
80+ Null -> guarder a
81+ NotNull -> guarder a
6782
6883
6984hnulls :: HTable t
70− => (forall labels necessity a. ()
71− => context ('Spec labels necessity (Maybe a)))
85+ => (forall a. Spec a -> context (Type.Nullify a))
7286 -> HNullify t context
73−hnulls null = HNullify $ htabulate $ \(HMapTableField field) -> case hfield hspecs field of
74− SSpec {} -> null
87+hnulls null = HNullify $ htabulate $ \(HMapTableField field) ->
88+ case hfield hspecs field of
89+ spec@Spec {} -> null spec
7590{-# INLINABLE hnulls #-}
7691
7792
7893hnullify :: HTable t
79− => (forall labels necessity a. ()
80− => SSpec ('Spec labels necessity a)
81− -> context ('Spec labels necessity a)
82− -> context ('Spec labels necessity (Type.Nullify a)))
94+ => (forall a. Spec a -> context a -> context (Type.Nullify a))
8395 -> t context
8496 -> HNullify t context
8597hnullify nullifier a = HNullify $ htabulate $ \(HMapTableField field) ->
8698 case hfield hspecs field of
87− spec@SSpec {} -> nullifier spec (hfield a field)
99+ spec@Spec {} -> nullifier spec (hfield a field)
88100{-# INLINABLE hnullify #-}
89101
90102
91103hunnullify :: (HTable t, Apply m)
92− => (forall labels necessity a. ()
93− => SSpec ('Spec labels necessity a)
94− -> context ('Spec labels necessity (Type.Nullify a))
95− -> m (context ('Spec labels necessity a)))
104+ => (forall a. Spec a -> context (Type.Nullify a) -> m (context a))
96105 -> HNullify t context
97106 -> m (t context)
98107hunnullify unnullifier (HNullify as) =
99108 htabulateA $ \field -> case hfield hspecs field of
100− spec@SSpec {} -> case hfield as (HMapTableField field) of
109+ spec@Spec {} -> case hfield as (HMapTableField field) of
101110 a -> unnullifier spec a
102111{-# INLINABLE hunnullify #-}
112+
113+
114+hproject :: ()
115+ => (forall ctx. t ctx -> t' ctx)
116+ -> HNullify t context -> HNullify t' context
117+hproject f (HNullify a) = HNullify (HMapTable.hproject f a)
src/Rel8/Schema/HTable/These.hs+2−4
@@ -14,21 +14,19 @@ import GHC.Generics ( Generic )
1414import Prelude
1515
1616-- rel8
17−import Rel8.Kind.Necessity ( Necessity( Required ) )
1817import Rel8.Schema.HTable ( HTable )
1918import Rel8.Schema.HTable.Identity ( HIdentity )
2019import Rel8.Schema.HTable.Label ( HLabel )
2120import Rel8.Schema.HTable.Nullify ( HNullify )
2221import qualified Rel8.Schema.Kind as K
23−import Rel8.Schema.Spec ( Spec( Spec ) )
2422import Rel8.Type.Tag ( MaybeTag )
2523
2624
2725type HTheseTable :: K.HTable -> K.HTable -> K.HTable
2826data HTheseTable here there context = HTheseTable
29− { hhereTag :: HIdentity ('Spec '["hasHere"] 'Required (Maybe MaybeTag)) context
27+ { hhereTag :: HLabel "hereTag" (HIdentity (Maybe MaybeTag)) context
3028 , hhere :: HLabel "Here" (HNullify here) context
31− , hthereTag :: HIdentity ('Spec '["hasThere"] 'Required (Maybe MaybeTag)) context
29+ , hthereTag :: HLabel "thereTag" (HIdentity (Maybe MaybeTag)) context
3230 , hthere :: HLabel "There" (HNullify there) context
3331 }
3432 deriving stock Generic
src/Rel8/Schema/HTable/Type.hsdeleted−61
@@ -1,61 +0,0 @@
1−{-# language DataKinds #-}
2−{-# language GADTs #-}
3−{-# language StandaloneKindSignatures #-}
4−{-# language TypeFamilies #-}
5−{-# language UndecidableInstances #-}
6−
7−module Rel8.Schema.HTable.Type
8− ( HType(..)
9− )
10−where
11−
12−-- base
13−import Data.Kind ( Type )
14−import Data.Proxy ( Proxy( Proxy ) )
15−import Prelude
16−
17−-- rel8
18−import Rel8.Kind.Labels ( SLabels( SLabel ) )
19−import Rel8.Kind.Necessity ( Necessity( Required ), SNecessity( SRequired ) )
20−import Rel8.Schema.Dict ( Dict( Dict ) )
21−import Rel8.Schema.HTable
22− ( HTable, HConstrainTable, HField
23− , hfield, htabulate, htraverse, hdicts, hspecs
24− )
25−import qualified Rel8.Schema.Kind as K
26−import Rel8.Schema.Null ( Sql, nullable )
27−import Rel8.Schema.Spec ( Spec( Spec ), SSpec(..) )
28−import Rel8.Type ( DBType, typeInformation )
29−
30−
31−type HType :: Type -> K.HTable
32−newtype HType a context = HType
33− { unHType :: context ('Spec '[""] 'Required a)
34− }
35−
36−
37−type HTypeField :: Type -> Spec -> Type
38−data HTypeField a spec where
39− HTypeField :: HTypeField a ('Spec '[""] 'Required a)
40−
41−
42−instance Sql DBType a => HTable (HType a) where
43− type HConstrainTable (HType a) c = c ('Spec '[""] 'Required a)
44− type HField (HType a) = HTypeField a
45−
46− hfield (HType a) HTypeField = a
47− htabulate f = HType $ f HTypeField
48− htraverse f (HType a) = HType <$> f a
49− hdicts = HType Dict
50− hspecs = HType SSpec
51− { labels = SLabel Proxy
52− , necessity = SRequired
53− , info = typeInformation
54− , nullity = nullable
55− }
56−
57− {-# INLINABLE hfield #-}
58− {-# INLINABLE htabulate #-}
59− {-# INLINABLE htraverse #-}
60− {-# INLINABLE hdicts #-}
61− {-# INLINABLE hspecs #-}
src/Rel8/Schema/HTable/Vectorize.hs+39−47
@@ -9,8 +9,6 @@
99{-# language GADTs #-}
1010{-# language LambdaCase #-}
1111{-# language MultiParamTypeClasses #-}
12−{-# language NamedFieldPuns #-}
13−{-# language QuantifiedConstraints #-}
1412{-# language RankNTypes #-}
1513{-# language RecordWildCards #-}
1614{-# language ScopedTypeVariables #-}
@@ -23,34 +21,39 @@ module Rel8.Schema.HTable.Vectorize
2321 ( HVectorize
2422 , hvectorize, hunvectorize
2523 , happend, hempty
24+ , hproject
25+ , hcolumn
2626 )
2727where
2828
2929-- base
30−import Data.Kind ( Type )
30+import Data.Kind ( Constraint, Type )
3131import Data.List.NonEmpty ( NonEmpty )
32+import GHC.Generics (Generic)
3233import Prelude
3334
3435-- rel8
35−import Rel8.Schema.Context.Label ( HLabelable, hlabeler, hunlabeler )
36+import Rel8.FCF ( Eval, Exp )
3637import Rel8.Schema.Dict ( Dict( Dict ) )
3738import qualified Rel8.Schema.Kind as K
38−import Rel8.Schema.HTable
39− ( HTable
40− , hfield, htabulate, htabulateA, hspecs
39+import Rel8.Schema.HTable ( HTable, hfield, htabulate, htabulateA, hspecs )
40+import Rel8.Schema.HTable.Identity ( HIdentity( HIdentity ) )
41+import Rel8.Schema.HTable.MapTable
42+ ( HMapTable( HMapTable ), HMapTableField( HMapTableField )
43+ , MapSpec, mapInfo
44+ , Precompose( Precompose )
4145 )
46+import qualified Rel8.Schema.HTable.MapTable as HMapTable ( hproject )
4247import Rel8.Schema.Null ( Unnullify, NotNull, Nullity( NotNull ) )
43−import Rel8.Schema.Spec ( Spec( Spec ), SSpec(..) )
48+import Rel8.Schema.Spec ( Spec(..) )
4449import Rel8.Type.Array ( listTypeInformation, nonEmptyTypeInformation )
4550import Rel8.Type.Information ( TypeInformation )
4651
4752-- semialign
48−import Data.Zip ( Unzip, Repeat, Zippy(..) )
49−import Rel8.FCF
50−import Rel8.Schema.HTable.MapTable
51−import GHC.Generics (Generic)
53+import Data.Zip ( Unzip, Zip, Zippy(..) )
5254
5355
56+type Vector :: (Type -> Type) -> Constraint
5457class Vector list where
5558 listNotNull :: proxy a -> Dict NotNull (list a)
5659 vectorTypeInformation :: ()
@@ -75,16 +78,16 @@ newtype HVectorize list table context = HVectorize (HMapTable (Vectorize list) t
7578 deriving anyclass HTable
7679
7780
78−data Vectorize :: (Type -> Type) -> Spec -> Exp Spec
81+data Vectorize :: (Type -> Type) -> Type -> Exp Type
7982
8083
81−type instance Eval (Vectorize list ('Spec labels necessity a)) = 'Spec labels necessity (list a)
84+type instance Eval (Vectorize list a) = list a
8285
8386
8487instance Vector list => MapSpec (Vectorize list) where
8588 mapInfo = \case
86− SSpec {..} -> case listNotNull @list nullity of
87− Dict -> SSpec
89+ Spec {..} -> case listNotNull @list nullity of
90+ Dict -> Spec
8891 { nullity = NotNull
8992 , info = vectorTypeInformation nullity info
9093 , ..
@@ -92,60 +95,49 @@ instance Vector list => MapSpec (Vectorize list) where
9295
9396
9497hvectorize :: (HTable t, Unzip f, Vector list)
95− => (forall labels necessity a. ()
96− => SSpec ('Spec labels necessity a)
97− -> f (context ('Spec labels necessity a))
98− -> context' ('Spec labels necessity (list a)))
98+ => (forall a. Spec a -> f (context a) -> context' (list a))
9999 -> f (t context)
100100 -> HVectorize list t context'
101101hvectorize vectorizer as = HVectorize $ htabulate $ \(HMapTableField field) ->
102102 case hfield hspecs field of
103− spec@SSpec {} -> vectorizer spec (fmap (`hfield` field) as)
103+ spec -> vectorizer spec (fmap (`hfield` field) as)
104104{-# INLINABLE hvectorize #-}
105105
106106
107−hunvectorize :: (HTable t, Repeat f, Vector list)
108− => (forall labels necessity a. ()
109− => SSpec ('Spec labels necessity a)
110− -> context ('Spec labels necessity (list a))
111− -> f (context' ('Spec labels necessity a)))
107+hunvectorize :: (HTable t, Zip f, Vector list)
108+ => (forall a. Spec a -> context (list a) -> f (context' a))
112109 -> HVectorize list t context
113110 -> f (t context')
114111hunvectorize unvectorizer (HVectorize table) =
115112 getZippy $ htabulateA $ \field -> case hfield hspecs field of
116− spec@SSpec{} -> case hfield table (HMapTableField field) of
113+ spec -> case hfield table (HMapTableField field) of
117114 a -> Zippy (unvectorizer spec a)
118115{-# INLINABLE hunvectorize #-}
119116
120117
121−happend :: (HTable t, Vector list) =>
122− ( forall labels necessity a. ()
123− => Nullity a
124− -> TypeInformation (Unnullify a)
125− -> context ('Spec labels necessity (list a))
126− -> context ('Spec labels necessity (list a))
127− -> context ('Spec labels necessity (list a))
128− )
118+happend :: (HTable t, Vector list)
119+ => (forall a. Spec a -> context (list a) -> context (list a) -> context (list a))
129120 -> HVectorize list t context
130121 -> HVectorize list t context
131122 -> HVectorize list t context
132123happend append (HVectorize as) (HVectorize bs) = HVectorize $
133124 htabulate $ \field@(HMapTableField j) -> case (hfield as field, hfield bs field) of
134125 (a, b) -> case hfield hspecs j of
135− SSpec {nullity, info} -> append nullity info a b
126+ spec -> append spec a b
136127
137128
138−hempty :: HTable t =>
139− ( forall labels necessity a. ()
140− => Nullity a
141− -> TypeInformation (Unnullify a)
142− -> context ('Spec labels necessity [a])
143− )
129+hempty :: HTable t
130+ => (forall a. Spec a -> context [a])
144131 -> HVectorize [] t context
145−hempty empty = HVectorize $ htabulate $ \(HMapTableField field) -> case hfield hspecs field of
146− SSpec {nullity, info} -> empty nullity info
132+hempty empty = HVectorize $ htabulate $ \(HMapTableField field) ->
133+ empty (hfield hspecs field)
134+
135+
136+hproject :: ()
137+ => (forall ctx. t ctx -> t' ctx)
138+ -> HVectorize list t context -> HVectorize list t' context
139+hproject f (HVectorize a) = HVectorize (HMapTable.hproject f a)
147140
148141
149−instance HLabelable g => HLabelable (Precompose (Vectorize list) g) where
150− hlabeler = Precompose . hlabeler . precomposed
151− hunlabeler = Precompose . hunlabeler . precomposed
142+hcolumn :: HVectorize list (HIdentity a) context -> context (list a)
143+hcolumn (HVectorize (HMapTable (HIdentity (Precompose a)))) = a
src/Rel8/Schema/Insert.hsdeleted−161
@@ -1,161 +0,0 @@
1−{-# language DataKinds #-}
2−{-# language DuplicateRecordFields #-}
3−{-# language FlexibleContexts #-}
4−{-# language FlexibleInstances #-}
5−{-# language GADTs #-}
6−{-# language LambdaCase #-}
7−{-# language MultiParamTypeClasses #-}
8−{-# language NamedFieldPuns #-}
9−{-# language PolyKinds #-}
10−{-# language StandaloneKindSignatures #-}
11−{-# language TypeFamilies #-}
12−{-# language UndecidableInstances #-}
13−{-# language UndecidableSuperClasses #-}
14−
15−module Rel8.Schema.Insert
16− ( Insert(..)
17− , OnConflict(..)
18− , Col( RequiredInsert, OptionalInsert )
19− , Inserts
20− , Insertion(..)
21− )
22−where
23−
24−-- base
25−import Data.Functor.Identity ( Identity )
26−import Data.Kind ( Constraint, Type )
27−import Prelude
28−
29−-- rel8
30−import Rel8.Aggregate ( Aggregate )
31−import Rel8.Expr ( Expr )
32−import Rel8.Kind.Necessity ( Necessity(Optional, Required) )
33−import Rel8.Schema.Context ( Interpretation(..) )
34−import Rel8.Schema.Context.Label ( Labelable(..) )
35−import Rel8.Schema.Context.Nullify
36− ( Nullifiable, encodeTag, decodeTag, nullifier, unnullifier
37− , runTag, unnull
38− )
39−import Rel8.Schema.HTable.Type ( HType( HType ) )
40−import Rel8.Schema.Name ( Name, Selects )
41−import Rel8.Schema.Null ( Sql )
42−import Rel8.Schema.Result ( Result )
43−import Rel8.Schema.Spec ( SSpec(SSpec, nullity), Spec(Spec) )
44−import Rel8.Schema.Table ( TableSchema )
45−import Rel8.Statement.Returning ( Returning )
46−import Rel8.Table ( Table(..) )
47−import Rel8.Table.Recontextualize ( Recontextualize )
48−import Rel8.Table.Tag ( Tag(..), fromExpr )
49−import Rel8.Type ( DBType )
50−
51−
52−-- | @OnConflict@ allows you to add an @ON CONFLICT@ clause to an @INSERT@
53−-- statement.
54−data OnConflict
55− = Abort -- ^ @ON CONFLICT ABORT@
56− | DoNothing -- ^ @ON CONFLICT DO NOTHING@
57−
58−
59−-- | The constituent parts of a SQL @INSERT@ statement.
60−type Insert :: k -> Type
61−data Insert a where
62− Insert :: (Selects names exprs, Inserts exprs inserts) =>
63− { into :: TableSchema names
64− -- ^ Which table to insert into.
65− , rows :: [inserts]
66− -- ^ The rows to insert.
67− , onConflict :: OnConflict
68− -- ^ What to do if the inserted rows conflict with data already in the
69− -- table.
70− , returning :: Returning names a
71− -- ^ What information to return on completion.
72− }
73− -> Insert a
74−
75−
76−instance Interpretation Insert where
77− data Col Insert _spec where
78− RequiredInsert :: Expr a -> Col Insert ('Spec labels 'Required a)
79− OptionalInsert :: Maybe (Expr a) -> Col Insert ('Spec labels 'Optional a)
80−
81−
82−type Insertion :: Type -> Type
83−newtype Insertion a = Insertion (Expr a)
84−
85−
86−instance Sql DBType a => Table Insert (Insertion a) where
87− type Columns (Insertion a) = HType a
88− type Context (Insertion a) = Insert
89−
90− toColumns (Insertion a) = HType (RequiredInsert a)
91− fromColumns (HType (RequiredInsert a)) = Insertion a
92−
93−
94−instance Sql DBType a =>
95− Recontextualize Aggregate Insert (Aggregate (Expr a)) (Insertion a)
96−
97−
98−instance Sql DBType a => Recontextualize Expr Insert (Expr a) (Insertion a)
99−
100−
101−instance Sql DBType a =>
102− Recontextualize Result Insert (Identity a) (Insertion a)
103−
104−
105−instance Sql DBType a =>
106− Recontextualize Insert Aggregate (Insertion a) (Aggregate (Expr a))
107−
108−
109−instance Sql DBType a => Recontextualize Insert Expr (Insertion a) (Expr a)
110−
111−
112−instance Sql DBType a =>
113− Recontextualize Insert Result (Insertion a) (Identity a)
114−
115−
116−instance Sql DBType a => Recontextualize Insert Insert (Insertion a) (Insertion a)
117−
118−
119−instance Sql DBType a => Recontextualize Insert Name (Insertion a) (Name a)
120−
121−
122−instance Sql DBType a => Recontextualize Name Insert (Name a) (Insertion a)
123−
124−
125−instance Labelable Insert where
126− labeler = \case
127− RequiredInsert a -> RequiredInsert a
128− OptionalInsert ma -> OptionalInsert ma
129−
130− unlabeler = \case
131− RequiredInsert a -> RequiredInsert a
132− OptionalInsert ma -> OptionalInsert ma
133−
134−
135−instance Nullifiable Insert where
136− encodeTag = RequiredInsert . expr
137− decodeTag (RequiredInsert a) = fromExpr a
138−
139− nullifier Tag {expr} test SSpec {nullity} = \case
140− RequiredInsert a ->
141− RequiredInsert $ runTag nullity condition a
142− OptionalInsert ma ->
143− OptionalInsert $ runTag nullity condition <$> ma
144− where
145− condition = test expr
146−
147− unnullifier SSpec {nullity} = \case
148− RequiredInsert a -> RequiredInsert $ unnull nullity a
149− OptionalInsert ma -> OptionalInsert $ unnull nullity <$> ma
150−
151− {-# INLINABLE encodeTag #-}
152− {-# INLINABLE decodeTag #-}
153− {-# INLINABLE nullifier #-}
154− {-# INLINABLE unnullifier #-}
155−
156−
157−-- | @Inserts a b@ means that the columns in @a@ are compatible for inserting
158−-- with the table @b@.
159−type Inserts :: Type -> Type -> Constraint
160−class Recontextualize Expr Insert exprs inserts => Inserts exprs inserts
161−instance Recontextualize Expr Insert exprs inserts => Inserts exprs inserts
src/Rel8/Schema/Kind.hs+8−17
@@ -1,8 +1,9 @@
11{-# language StandaloneKindSignatures #-}
22
33module Rel8.Schema.Kind
4− ( Context, Table
5− , HContext, HTable
4+ ( Rel8able
5+ , Context
6+ , HTable
67 )
78where
89
@@ -10,24 +11,14 @@ where
1011import Data.Kind ( Type )
1112import Prelude ()
1213
13−-- rel8
14−import Rel8.Schema.Spec ( Spec )
1514
16−
17−type HContext :: Type
18−type HContext = Spec -> Type
15+type Context :: Type
16+type Context = Type -> Type
1917
2018
2119type HTable :: Type
22−type HTable = HContext -> Type
23−
24−
25−data X
26−
27−
28−type Context :: Type
29−type Context = X -> Type
20+type HTable = Context -> Type
3021
3122
32−type Table :: Type
33−type Table = Context -> Type
23+type Rel8able :: Type
24+type Rel8able = Context -> Type
src/Rel8/Schema/Name.hs+36−51
@@ -3,37 +3,44 @@
33{-# language FlexibleContexts #-}
44{-# language FlexibleInstances #-}
55{-# language GADTs #-}
6+{-# language GeneralizedNewtypeDeriving #-}
67{-# language MultiParamTypeClasses #-}
7−{-# language PolyKinds #-}
88{-# language RankNTypes #-}
9−{-# language StandaloneDeriving #-}
109{-# language StandaloneKindSignatures #-}
1110{-# language TypeFamilies #-}
1211{-# language UndecidableInstances #-}
13−{-# language UndecidableSuperClasses #-}
1412
1513module Rel8.Schema.Name
1614 ( Name(..)
17− , Col( NameCol )
1815 , Selects
16+ , ppColumn
1917 )
2018where
2119
2220-- base
23−import Data.Functor.Identity ( Identity )
21+import Data.Functor.Identity ( Identity( Identity ) )
2422import Data.Kind ( Constraint, Type )
25−import Data.String ( IsString, fromString )
23+import Data.String ( IsString )
2624import Prelude
2725
26+-- opaleye
27+import qualified Opaleye.Internal.HaskellDB.Sql as Opaleye
28+import qualified Opaleye.Internal.HaskellDB.Sql.Print as Opaleye
29+
30+-- pretty
31+import Text.PrettyPrint ( Doc )
32+
2833-- rel8
2934import Rel8.Expr ( Expr )
30−import Rel8.Schema.Context ( Interpretation, Col )
31−import Rel8.Schema.Context.Label ( Labelable, labeler, unlabeler )
32−import Rel8.Schema.HTable.Type ( HType( HType ) )
35+import qualified Rel8.Schema.Kind as K
36+import Rel8.Schema.HTable.Identity ( HIdentity( HIdentity ) )
3337import Rel8.Schema.Null ( Sql )
34−import Rel8.Schema.Result ( Result )
35−import Rel8.Table ( Table, Columns, Context, fromColumns, toColumns )
36−import Rel8.Table.Recontextualize ( Recontextualize )
38+import Rel8.Table
39+ ( Table, Columns, Context, fromColumns, toColumns
40+ , FromExprs, fromResult, toResult
41+ , Transpose
42+ )
43+import Rel8.Table.Transpose ( Transposes )
3744import Rel8.Type ( DBType )
3845
3946
@@ -41,52 +48,30 @@ import Rel8.Type ( DBType )
4148-- schema definition. You can construct names by using the @OverloadedStrings@
4249-- extension and writing string literals. This is typically done when providing
4350-- a 'TableSchema' value.
44−type Name :: k -> Type
45−data Name a where
46− Name :: k ~ Type => !String -> Name (a :: k)
47−
48−
49−deriving stock instance Show (Name a)
50−
51−
52−instance k ~ Type => IsString (Name (a :: k)) where
53− fromString = Name
51+type Name :: K.Context
52+newtype Name a = Name String
53+ deriving stock Show
54+ deriving newtype IsString
5455
5556
5657instance Sql DBType a => Table Name (Name a) where
57− type Columns (Name a) = HType a
58+ type Columns (Name a) = HIdentity a
5859 type Context (Name a) = Name
60+ type FromExprs (Name a) = a
61+ type Transpose to (Name a) = to a
5962
60− toColumns (Name a) = HType (NameCol a)
61− fromColumns (HType (NameCol a)) = Name a
62−
63−
64−instance Sql DBType a => Recontextualize Expr Name (Expr a) (Name a)
65−
66−
67−instance Sql DBType a => Recontextualize Result Name (Identity a) (Name a)
68−
69−
70−instance Sql DBType a => Recontextualize Name Expr (Name a) (Expr a)
71−
72−
73−instance Sql DBType a => Recontextualize Name Result (Name a) (Identity a)
74−
75−
76−instance Sql DBType a => Recontextualize Name Name (Name a) (Name a)
77−
78−
79−instance Interpretation Name where
80− newtype Col Name _spec = NameCol String
81−
82−
83−instance Labelable Name where
84− labeler (NameCol a) = NameCol a
85− unlabeler (NameCol a) = NameCol a
63+ toColumns a = HIdentity a
64+ fromColumns (HIdentity a) = a
65+ toResult a = HIdentity (Identity a)
66+ fromResult (HIdentity (Identity a)) = a
8667
8768
8869-- | @Selects a b@ means that @a@ is a schema (i.e., a 'Table' of 'Name's) for
8970-- the 'Expr' columns in @b@.
9071type Selects :: Type -> Type -> Constraint
91−class Recontextualize Name Expr names exprs => Selects names exprs
92−instance Recontextualize Name Expr names exprs => Selects names exprs
72+class Transposes Name Expr names exprs => Selects names exprs
73+instance Transposes Name Expr names exprs => Selects names exprs
74+
75+
76+ppColumn :: String -> Doc
77+ppColumn = Opaleye.ppSqlExpr . Opaleye.ColumnSqlExpr . Opaleye.SqlColumn
src/Rel8/Schema/Result.hs+41−3
@@ -1,16 +1,54 @@
11{-# language DataKinds #-}
2+{-# language GADTs #-}
3+{-# language NamedFieldPuns #-}
24{-# language StandaloneKindSignatures #-}
5+{-# language TypeFamilies #-}
36
47module Rel8.Schema.Result
58 ( Result
6− ) where
9+ , null, nullifier, unnullifier
10+ , vectorizer, unvectorizer
11+ )
12+where
713
814-- base
9−import Prelude ()
15+import Data.Functor.Identity ( Identity( Identity), runIdentity )
16+import Prelude hiding ( null )
1017
1118-- rel8
1219import Rel8.Schema.Kind ( Context )
20+import Rel8.Schema.Null ( Nullify, Nullity( Null, NotNull ) )
21+import Rel8.Schema.Spec ( Spec(..) )
1322
1423
24+-- | The @Result@ context is the context used for decoded query results.
25+--
26+-- When a query is executed against a PostgreSQL database, Rel8 parses the
27+-- returned rows, decoding each row into the @Result@ context.
1528type Result :: Context
16−data Result a
29+type Result = Identity
30+
31+
32+null :: Result (Maybe a)
33+null = Identity Nothing
34+
35+
36+nullifier :: Spec a -> Result a -> Result (Nullify a)
37+nullifier Spec {nullity} (Identity a) = Identity $ case nullity of
38+ Null -> a
39+ NotNull -> Just a
40+
41+
42+unnullifier :: Spec a -> Result (Nullify a) -> Maybe (Result a)
43+unnullifier Spec {nullity} (Identity a) =
44+ case nullity of
45+ Null -> pure $ Identity a
46+ NotNull -> Identity <$> a
47+
48+
49+vectorizer :: Functor f => Spec a -> f (Result a) -> Result (f a)
50+vectorizer _ = Identity . fmap runIdentity
51+
52+
53+unvectorizer :: Functor f => Spec a -> Result (f a) -> f (Result a)
54+unvectorizer _ (Identity results) = Identity <$> results
src/Rel8/Schema/Spec.hs+17−45
@@ -1,62 +1,34 @@
1−{-# language DataKinds #-}
21{-# language FlexibleContexts #-}
3−{-# language GADTs #-}
2+{-# language MonoLocalBinds #-}
43{-# language StandaloneKindSignatures #-}
5−{-# language UndecidableInstances #-}
64
75module Rel8.Schema.Spec
8− ( Spec( Spec )
9− , SSpec( SSpec, labels, necessity, info, nullity )
10− , KnownSpec( specSing )
6+ ( Spec( Spec, labels, info, nullity )
7+ , specification
118 )
129where
1310
1411-- base
15−import Data.Kind ( Constraint, Type )
16−import Prelude ()
12+import Data.Kind ( Type )
13+import Prelude
1714
1815-- rel8
19−import Rel8.Kind.Labels ( Labels, SLabels, KnownLabels, labelsSing )
20−import Rel8.Kind.Necessity
21− ( Necessity
22− , SNecessity
23− , KnownNecessity, necessitySing
24− )
2516import Rel8.Schema.Null ( Nullity, Sql, Unnullify, nullable )
2617import Rel8.Type ( DBType, typeInformation )
2718import Rel8.Type.Information ( TypeInformation )
2819
2920
30−type Spec :: Type
31−data Spec = Spec Labels Necessity Type
32−
33−
34−type SSpec :: Spec -> Type
35−data SSpec spec where
36− SSpec ::
37− { labels :: SLabels labels
38− , necessity :: SNecessity necessity
39− , info :: TypeInformation (Unnullify a)
40− , nullity :: Nullity a
41− }
42− -> SSpec ('Spec labels necessity a)
21+type Spec :: Type -> Type
22+data Spec a = Spec
23+ { labels :: [String]
24+ , info :: TypeInformation (Unnullify a)
25+ , nullity :: Nullity a
26+ }
4327
4428
45−type KnownSpec :: Spec -> Constraint
46−class KnownSpec spec where
47− specSing :: SSpec spec
48−
49−
50−instance
51− ( KnownLabels labels
52− , KnownNecessity necessity
53− , Sql DBType a
54− )
55− => KnownSpec ('Spec labels necessity a)
56− where
57− specSing = SSpec
58− { labels = labelsSing
59− , necessity = necessitySing
60− , info = typeInformation
61− , nullity = nullable
62− }
29+specification :: Sql DBType a => Spec a
30+specification = Spec
31+ { labels = []
32+ , info = typeInformation
33+ , nullity = nullable
34+ }
src/Rel8/Schema/Spec/ConstrainDBType.hsdeleted−64
@@ -1,64 +0,0 @@
1−{-# language ConstraintKinds #-}
2−{-# language DataKinds #-}
3−{-# language FlexibleInstances #-}
4−{-# language MultiParamTypeClasses #-}
5−{-# language QuantifiedConstraints #-}
6−{-# language StandaloneKindSignatures #-}
7−{-# language TypeFamilies #-}
8−{-# language UndecidableInstances #-}
9−
10−module Rel8.Schema.Spec.ConstrainDBType
11− ( ConstrainDBType
12− , dbTypeNullity
13− , dbTypeDict
14− , fromNullityDict
15− )
16−where
17−
18−-- base
19−import Data.Kind ( Constraint, Type )
20−import Prelude
21−
22−-- rel8
23−import Rel8.Schema.Dict ( Dict( Dict ) )
24−import Rel8.Schema.Null ( Unnullify, Nullity( Null, NotNull ), Sql, nullable )
25−import Rel8.Schema.Spec ( Spec( Spec ) )
26−
27−
28−type ConstrainDBType :: (Type -> Constraint) -> Spec -> Constraint
29−class
30− ( forall c labels necessity a. ()
31− => (spec ~ 'Spec labels necessity a)
32− => (forall x. (constraint x => c x)) => Sql c a
33− )
34− => ConstrainDBType constraint spec
35−instance
36− ( spec ~ 'Spec labels necessity a
37− , Sql constraint a
38− )
39− => ConstrainDBType constraint spec
40−
41−
42−dbTypeNullity :: Dict (ConstrainDBType c) ('Spec l n a) -> Nullity a
43−dbTypeNullity = step2 . step1
44− where
45− step1 :: Dict (ConstrainDBType c) ('Spec l n a) -> Dict (Sql c) a
46− step1 Dict = Dict
47−
48− step2 :: Dict (Sql c) a -> Nullity a
49− step2 Dict = nullable
50−
51−
52−dbTypeDict :: Dict (ConstrainDBType c) ('Spec l n a) -> Dict c (Unnullify a)
53−dbTypeDict = step2 . step1
54− where
55− step1 :: Dict (ConstrainDBType c) ('Spec l n a) -> Dict (Sql c) a
56− step1 Dict = Dict
57−
58− step2 :: Dict (Sql c) a -> Dict c (Unnullify a)
59− step2 Dict = Dict
60−
61−
62−fromNullityDict :: Nullity a -> Dict c (Unnullify a) -> Dict (ConstrainDBType c) ('Spec l n a)
63−fromNullityDict Null Dict = Dict
64−fromNullityDict NotNull Dict = Dict
src/Rel8/Schema/Spec/ConstrainType.hsdeleted−31
@@ -1,31 +0,0 @@
1−{-# language ConstraintKinds #-}
2−{-# language DataKinds #-}
3−{-# language FlexibleInstances #-}
4−{-# language MultiParamTypeClasses #-}
5−{-# language QuantifiedConstraints #-}
6−{-# language StandaloneKindSignatures #-}
7−{-# language TypeFamilies #-}
8−{-# language UndecidableInstances #-}
9−
10−module Rel8.Schema.Spec.ConstrainType
11− ( ConstrainType
12− )
13−where
14−
15−-- base
16−import Data.Kind ( Constraint, Type )
17−import Prelude ()
18−
19−-- rel8
20−import Rel8.Schema.Spec ( Spec( Spec ) )
21−
22−
23−type ConstrainType :: (Type -> Constraint) -> Spec -> Constraint
24−class
25− ( forall labels necessity a. ()
26− => (spec ~ 'Spec labels necessity a)
27− => constraint a
28− ) =>
29− ConstrainType constraint spec
30−instance (spec ~ 'Spec labels necessity a, constraint a) =>
31− ConstrainType constraint spec
src/Rel8/Schema/Structure.hsdeleted−17
@@ -1,17 +0,0 @@
1−{-# language DataKinds #-}
2−{-# language StandaloneKindSignatures #-}
3−
4−module Rel8.Schema.Structure
5− ( Structure
6− )
7−where
8−
9−-- base
10−import Prelude ()
11−
12−-- rel8
13−import Rel8.Schema.Kind ( Context )
14−
15−
16−type Structure :: Context
17−data Structure a
src/Rel8/Schema/Table.hs+20
@@ -1,14 +1,26 @@
11{-# language DeriveFunctor #-}
22{-# language DerivingStrategies #-}
3+{-# language DisambiguateRecordFields #-}
4+{-# language NamedFieldPuns #-}
5+{-# language StandaloneKindSignatures #-}
36
47module Rel8.Schema.Table
58 ( TableSchema(..)
9+ , ppTable
610 )
711where
812
913-- base
14+import Data.Kind ( Type )
1015import Prelude
1116
17+-- opaleye
18+import qualified Opaleye.Internal.HaskellDB.Sql as Opaleye
19+import qualified Opaleye.Internal.HaskellDB.Sql.Print as Opaleye
20+
21+-- pretty
22+import Text.PrettyPrint ( Doc )
23+
1224
1325-- | The schema for a table. This is used to specify the name and schema that a
1426-- table belongs to (the @FROM@ part of a SQL query), along with the schema of
@@ -16,6 +28,7 @@ import Prelude
1628--
1729-- For each selectable table in your database, you should provide a
1830-- @TableSchema@ in order to interact with the table via Rel8.
31+type TableSchema :: Type -> Type
1932data TableSchema names = TableSchema
2033 { name :: String
2134 -- ^ The name of the table.
@@ -27,3 +40,10 @@ data TableSchema names = TableSchema
2740 -- data type here, parameterized by the 'Rel8.ColumnSchema.ColumnSchema' functor.
2841 }
2942 deriving stock Functor
43+
44+
45+ppTable :: TableSchema a -> Doc
46+ppTable TableSchema {name, schema} = Opaleye.ppTable Opaleye.SqlTable
47+ { sqlTableSchemaName = schema
48+ , sqlTableName = name
49+ }
src/Rel8/Statement/Delete.hs+35−48
@@ -1,40 +1,37 @@
11{-# language DuplicateRecordFields #-}
22{-# language GADTs #-}
33{-# language NamedFieldPuns #-}
4−{-# language ScopedTypeVariables #-}
4+{-# language RankNTypes #-}
5+{-# language RecordWildCards #-}
56{-# language StandaloneKindSignatures #-}
6−{-# language TypeApplications #-}
7+{-# language StrictData #-}
78
89module Rel8.Statement.Delete
910 ( Delete(..)
1011 , delete
12+ , ppDelete
1113 )
1214where
1315
1416-- base
15−import Control.Exception ( throwIO )
1617import Data.Kind ( Type )
1718import Prelude
1819
1920-- hasql
20−import Hasql.Connection ( Connection )
21−import qualified Hasql.Decoders as Hasql
2221import qualified Hasql.Encoders as Hasql
23−import qualified Hasql.Session as Hasql
2422import qualified Hasql.Statement as Hasql
2523
26−-- opaleye
27−import qualified Opaleye.Internal.Manipulation as Opaleye
24+-- pretty
25+import Text.PrettyPrint ( Doc, (<+>), ($$), text )
2826
2927-- rel8
3028import Rel8.Expr ( Expr )
31−import Rel8.Expr.Opaleye ( toColumn, toPrimExpr )
29+import Rel8.Query ( Query )
3230import Rel8.Schema.Name ( Selects )
33−import Rel8.Schema.Table ( TableSchema )
34−import Rel8.Statement.Returning ( Returning( NumberOfRowsAffected, Projection ) )
35−import Rel8.Table ( fromColumns, toColumns )
36−import Rel8.Table.Opaleye ( castTable, table, unpackspec )
37−import Rel8.Table.Serialize ( Serializable, parse )
31+import Rel8.Schema.Table ( TableSchema, ppTable )
32+import Rel8.Statement.Returning ( Returning, decodeReturning, ppReturning )
33+import Rel8.Statement.Using ( ppUsing )
34+import Rel8.Statement.Where ( ppWhere )
3835
3936-- text
4037import qualified Data.Text as Text
@@ -47,7 +44,10 @@ data Delete a where
4744 Delete :: Selects names exprs =>
4845 { from :: TableSchema names
4946 -- ^ Which table to delete from.
50− , deleteWhere :: exprs -> Expr Bool
47+ , using :: Query using
48+ -- ^ @USING@ clause — this can be used to join against other tables,
49+ -- and its results can be referenced in the @WHERE@ clause
50+ , deleteWhere :: using -> exprs -> Expr Bool
5151 -- ^ Which rows should be selected for deletion.
5252 , returning :: Returning names a
5353 -- ^ What to return from the @DELETE@ statement.
@@ -55,38 +55,25 @@ data Delete a where
5555 -> Delete a
5656
5757
58−-- | Run a @DELETE@ statement.
59−delete :: Connection -> Delete a -> IO a
60−delete c Delete {from, deleteWhere, returning} =
61− case returning of
62− NumberOfRowsAffected -> Hasql.run session c >>= either throwIO pure
63− where
64− session = Hasql.statement () statement
65− statement = Hasql.Statement bytes params decode prepare
66− bytes = encodeUtf8 $ Text.pack sql
67− params = Hasql.noParams
68− decode = Hasql.rowsAffected
69− prepare = False
70− sql = Opaleye.arrangeDeleteSql from' where'
71− where
72− from' = table $ toColumns <$> from
73− where' = toColumn . toPrimExpr . deleteWhere . fromColumns
58+ppDelete :: Delete a -> Doc
59+ppDelete Delete {..} = case ppUsing using of
60+ Nothing ->
61+ text "DELETE FROM" <+> ppTable from $$
62+ text "WHERE false"
63+ Just (usingDoc, i) ->
64+ text "DELETE FROM" <+> ppTable from $$
65+ usingDoc $$
66+ ppWhere from (deleteWhere i) $$
67+ ppReturning from returning
7468
75− Projection project -> Hasql.run session c >>= either throwIO pure
76− where
77− session = Hasql.statement () statement
78− statement = Hasql.Statement bytes params decode prepare
79− bytes = encodeUtf8 $ Text.pack sql
80− params = Hasql.noParams
81− decode = decoder project
82− prepare = False
83− sql =
84− Opaleye.arrangeDeleteReturningSql unpackspec from' where' project'
85− where
86− from' = table $ toColumns <$> from
87− where' = toColumn . toPrimExpr . deleteWhere . fromColumns
88− project' = castTable . toColumns . project . fromColumns
69+
70+-- | Run a 'Delete' statement.
71+delete :: Delete a -> Hasql.Statement () a
72+delete d@Delete {returning} = Hasql.Statement bytes params decode prepare
8973 where
90− decoder :: forall exprs projection a. Serializable projection a
91− => (exprs -> projection) -> Hasql.Result [a]
92− decoder _ = Hasql.rowList (parse @projection @a)
74+ bytes = encodeUtf8 $ Text.pack sql
75+ params = Hasql.noParams
76+ decode = decodeReturning returning
77+ prepare = False
78+ sql = show doc
79+ doc = ppDelete d
src/Rel8/Statement/Insert.hs+60−60
@@ -1,89 +1,89 @@
1+{-# language DuplicateRecordFields #-}
2+{-# language FlexibleContexts #-}
13{-# language GADTs #-}
24{-# language NamedFieldPuns #-}
3−{-# language ScopedTypeVariables #-}
4−{-# language TypeApplications #-}
5+{-# language RecordWildCards #-}
6+{-# language StandaloneKindSignatures #-}
7+{-# language StrictData #-}
58
69module Rel8.Statement.Insert
710 ( Insert(..)
8− , OnConflict(..)
911 , insert
12+ , ppInsert
13+ , ppInto
1014 )
1115where
1216
1317-- base
14−import Control.Exception ( throwIO )
15−import Data.List.NonEmpty ( NonEmpty( (:|) ) )
18+import Data.Foldable ( toList )
19+import Data.Kind ( Type )
1620import Prelude
1721
1822-- hasql
19−import Hasql.Connection ( Connection )
20−import qualified Hasql.Decoders as Hasql
2123import qualified Hasql.Encoders as Hasql
22−import qualified Hasql.Session as Hasql
2324import qualified Hasql.Statement as Hasql
2425
2526-- opaleye
26−import qualified Opaleye.Internal.Manipulation as Opaleye
27−import qualified Opaleye.Manipulation as Opaleye
27+import qualified Opaleye.Internal.HaskellDB.Sql.Print as Opaleye
28+
29+-- pretty
30+import Text.PrettyPrint ( Doc, (<+>), ($$), parens, text )
2831
2932-- rel8
30−import Rel8.Schema.Insert ( Insert(..), OnConflict(..) )
31−import Rel8.Statement.Returning ( Returning( Projection, NumberOfRowsAffected ) )
32−import Rel8.Table ( fromColumns, toColumns )
33−import Rel8.Table.Opaleye ( castTable, table, unpackspec )
34−import Rel8.Table.Serialize ( Serializable, parse )
33+import Rel8.Query ( Query )
34+import Rel8.Schema.Name ( Name, Selects, ppColumn )
35+import Rel8.Schema.Table ( TableSchema(..), ppTable )
36+import Rel8.Statement.OnConflict ( OnConflict, ppOnConflict )
37+import Rel8.Statement.Returning ( Returning, decodeReturning, ppReturning )
38+import Rel8.Statement.Select ( ppRows )
39+import Rel8.Table ( Table )
40+import Rel8.Table.Name ( showNames )
3541
3642-- text
3743import qualified Data.Text as Text ( pack )
3844import Data.Text.Encoding ( encodeUtf8 )
3945
4046
41−-- | Run an @INSERT@ statement
42−insert :: Connection -> Insert a -> IO a
43−insert c Insert {into, rows, onConflict, returning} =
44− case (rows, returning) of
45− ([], NumberOfRowsAffected) -> pure 0
46− ([], Projection _) -> pure []
47+-- | The constituent parts of a SQL @INSERT@ statement.
48+type Insert :: Type -> Type
49+data Insert a where
50+ Insert :: Selects names exprs =>
51+ { into :: TableSchema names
52+ -- ^ Which table to insert into.
53+ , rows :: Query exprs
54+ -- ^ The rows to insert. This can be an arbitrary query — use
55+ -- 'Rel8.values' insert a static list of rows.
56+ , onConflict :: OnConflict names
57+ -- ^ What to do if the inserted rows conflict with data already in the
58+ -- table.
59+ , returning :: Returning names a
60+ -- ^ What information to return on completion.
61+ }
62+ -> Insert a
4763
48− (x:xs, NumberOfRowsAffected) -> Hasql.run session c >>= either throwIO pure
49− where
50− session = Hasql.statement () statement
51− statement = Hasql.Statement bytes params decode prepare
52− bytes = encodeUtf8 $ Text.pack sql
53− params = Hasql.noParams
54− decode = Hasql.rowsAffected
55− prepare = False
56− sql = Opaleye.arrangeInsertManySql into' rows' onConflict'
57− where
58− into' = table $ toColumns <$> into
59− rows' = toColumns <$> x :| xs
6064
61− (x:xs, Projection project) -> Hasql.run session c >>= either throwIO pure
62− where
63− session = Hasql.statement () statement
64− statement = Hasql.Statement bytes params decode prepare
65− bytes = encodeUtf8 $ Text.pack sql
66− params = Hasql.noParams
67− decode = decoder project
68− prepare = False
69− sql =
70− Opaleye.arrangeInsertManyReturningSql
71− unpackspec
72− into'
73− rows'
74− project'
75− onConflict'
76− where
77− into' = table $ toColumns <$> into
78− rows' = toColumns <$> x :| xs
79− project' = castTable . toColumns . project . fromColumns
65+ppInsert :: Insert a -> Doc
66+ppInsert Insert {..} =
67+ text "INSERT INTO" <+>
68+ ppInto into $$
69+ ppRows rows $$
70+ ppOnConflict into onConflict $$
71+ ppReturning into returning
8072
81− where
82− onConflict' =
83− case onConflict of
84− DoNothing -> Just Opaleye.DoNothing
85− Abort -> Nothing
8673
87− decoder :: forall exprs projection a. Serializable projection a
88− => (exprs -> projection) -> Hasql.Result [a]
89− decoder _ = Hasql.rowList (parse @projection @a)
74+ppInto :: Table Name a => TableSchema a -> Doc
75+ppInto table@TableSchema {columns} =
76+ ppTable table <+>
77+ parens (Opaleye.commaV ppColumn (toList (showNames columns)))
78+
79+
80+-- | Run an 'Insert' statement.
81+insert :: Insert a -> Hasql.Statement () a
82+insert i@Insert {returning} = Hasql.Statement bytes params decode prepare
83+ where
84+ bytes = encodeUtf8 $ Text.pack sql
85+ params = Hasql.noParams
86+ decode = decodeReturning returning
87+ prepare = False
88+ sql = show doc
89+ doc = ppInsert i
src/Rel8/Statement/OnConflict.hsnew file+106
@@ -0,0 +1,106 @@
1+{-# language DuplicateRecordFields #-}
2+{-# language FlexibleContexts #-}
3+{-# language GADTs #-}
4+{-# language LambdaCase #-}
5+{-# language NamedFieldPuns #-}
6+{-# language RecordWildCards #-}
7+{-# language StandaloneKindSignatures #-}
8+{-# language StrictData #-}
9+
10+module Rel8.Statement.OnConflict
11+ ( OnConflict(..)
12+ , Upsert(..)
13+ , ppOnConflict
14+ )
15+where
16+
17+-- base
18+import Data.Foldable ( toList )
19+import Data.Kind ( Type )
20+import Prelude
21+
22+-- opaleye
23+import qualified Opaleye.Internal.HaskellDB.Sql.Print as Opaleye
24+
25+-- pretty
26+import Text.PrettyPrint ( Doc, (<+>), ($$), parens, text )
27+
28+-- rel8
29+import Rel8.Expr ( Expr )
30+import Rel8.Schema.Name ( Name, Selects, ppColumn )
31+import Rel8.Schema.Table ( TableSchema(..) )
32+import Rel8.Statement.Set ( ppSet )
33+import Rel8.Statement.Where ( ppWhere )
34+import Rel8.Table ( Table, toColumns )
35+import Rel8.Table.Cols ( Cols( Cols ) )
36+import Rel8.Table.Name ( showNames )
37+import Rel8.Table.Opaleye ( attributes )
38+import Rel8.Table.Projection ( Projecting, Projection, apply )
39+
40+
41+-- | 'OnConflict' represents the @ON CONFLICT@ clause of an @INSERT@
42+-- statement. This specifies what ought to happen when one or more of the
43+-- rows proposed for insertion conflict with an existing row in the table.
44+type OnConflict :: Type -> Type
45+data OnConflict names
46+ = Abort
47+ -- ^ Abort the transaction if there are conflicting rows (Postgres' default)
48+ | DoNothing
49+ -- ^ @ON CONFLICT DO NOTHING@
50+ | DoUpdate (Upsert names)
51+ -- ^ @ON CONFLICT DO UPDATE@
52+
53+
54+-- | The @ON CONFLICT (...) DO UPDATE@ clause of an @INSERT@ statement, also
55+-- known as \"upsert\".
56+--
57+-- When an existing row conflicts with a row proposed for insertion,
58+-- @ON CONFLICT DO UPDATE@ allows you to instead update this existing row. The
59+-- conflicting row proposed for insertion is then \"excluded\", but its values
60+-- can still be referenced from the @SET@ and @WHERE@ clauses of the @UPDATE@
61+-- statement.
62+--
63+-- Upsert in Postgres requires an explicit set of \"conflict targets\" — the
64+-- set of columns comprising the @UNIQUE@ index from conflicts with which we
65+-- would like to recover.
66+type Upsert :: Type -> Type
67+data Upsert names where
68+ Upsert :: (Selects names exprs, Projecting names index, excluded ~ exprs) =>
69+ { index :: Projection names index
70+ -- ^ The set of conflict targets, projected from the set of columns for
71+ -- the whole table
72+ , set :: excluded -> exprs -> exprs
73+ -- ^ How to update each selected row.
74+ , updateWhere :: excluded -> exprs -> Expr Bool
75+ -- ^ Which rows to select for update.
76+ }
77+ -> Upsert names
78+
79+
80+ppOnConflict :: TableSchema names -> OnConflict names -> Doc
81+ppOnConflict schema = \case
82+ Abort -> mempty
83+ DoNothing -> text "ON CONFLICT DO NOTHING"
84+ DoUpdate upsert -> ppUpsert schema upsert
85+
86+
87+ppUpsert :: TableSchema names -> Upsert names -> Doc
88+ppUpsert schema@TableSchema {columns} Upsert {..} =
89+ text "ON CONFLICT" <+>
90+ ppIndex schema index <+>
91+ text "DO UPDATE" $$
92+ ppSet schema (set excluded) $$
93+ ppWhere schema (updateWhere excluded)
94+ where
95+ excluded = attributes TableSchema
96+ { schema = Nothing
97+ , name = "excluded"
98+ , columns
99+ }
100+
101+
102+ppIndex :: (Table Name names, Projecting names index)
103+ => TableSchema names -> Projection names index -> Doc
104+ppIndex TableSchema {columns} index =
105+ parens $ Opaleye.commaV ppColumn $ toList $
106+ showNames $ Cols $ apply index $ toColumns columns
src/Rel8/Statement/Returning.hs+114−10
@@ -1,29 +1,133 @@
11{-# language GADTs #-}
2+{-# language LambdaCase #-}
3+{-# language NamedFieldPuns #-}
4+{-# language RankNTypes #-}
5+{-# language ScopedTypeVariables #-}
26{-# language StandaloneKindSignatures #-}
7+{-# language StrictData #-}
8+{-# language TypeApplications #-}
39
410module Rel8.Statement.Returning
5− ( Returning(..)
11+ ( Returning( NumberOfRowsAffected, Projection )
12+ , decodeReturning
13+ , ppReturning
614 )
715where
816
917-- base
18+import Control.Applicative ( liftA2 )
19+import Data.Foldable ( toList )
1020import Data.Int ( Int64 )
1121import Data.Kind ( Type )
12−import Prelude ()
22+import Data.List.NonEmpty ( NonEmpty )
23+import Prelude
24+
25+-- hasql
26+import qualified Hasql.Decoders as Hasql
27+
28+-- opaleye
29+import qualified Opaleye.Internal.HaskellDB.PrimQuery as Opaleye
30+import qualified Opaleye.Internal.HaskellDB.Sql.Print as Opaleye
31+import qualified Opaleye.Internal.Sql as Opaleye
32+
33+-- pretty
34+import Text.PrettyPrint ( Doc, (<+>), text )
1335
1436-- rel8
1537import Rel8.Schema.Name ( Selects )
16−import Rel8.Table.Serialize ( Serializable )
38+import Rel8.Schema.Table ( TableSchema(..) )
39+import Rel8.Table.Opaleye ( castTable, exprs, view )
40+import Rel8.Table.Serialize ( Serializable, parse )
1741
42+-- semigropuoids
43+import Data.Functor.Apply ( Apply, (<.>) )
1844
19−-- | @INSERT@, @UPDATE@ and @DELETE@ all support returning either the number of
20−-- rows affected, or the actual rows modified. 'Projection' allows you to
21−-- project out of these returned rows, which can be useful if you want to log
22−-- exactly which rows were deleted, or to view a generated id (for example, if
23−-- using a column with an autoincrementing counter as a default value).
45+
46+-- | 'Rel8.Insert', 'Rel8.Update' and 'Rel8.Delete' all support returning either
47+-- the number of rows affected, or the actual rows modified.
2448type Returning :: Type -> Type -> Type
2549data Returning names a where
50+ Pure :: a -> Returning names a
51+ Ap :: Returning names (a -> b) -> Returning names a -> Returning names b
52+
53+ -- | Return the number of rows affected.
2654 NumberOfRowsAffected :: Returning names Int64
27− Projection :: (Selects names exprs, Serializable projection a)
28− => (exprs -> projection)
55+
56+ -- | 'Projection' allows you to project out of the affected rows, which can
57+ -- be useful if you want to log exactly which rows were deleted, or to view
58+ -- a generated id (for example, if using a column with an autoincrementing
59+ -- counter via 'Rel8.nextval').
60+ Projection :: (Selects names exprs, Serializable returning a)
61+ => (exprs -> returning)
2962 -> Returning names [a]
63+
64+
65+instance Functor (Returning names) where
66+ fmap f = \case
67+ Pure a -> Pure (f a)
68+ Ap g a -> Ap (fmap (f .) g) a
69+ m -> Ap (Pure f) m
70+
71+
72+instance Apply (Returning names) where
73+ (<.>) = Ap
74+
75+
76+instance Applicative (Returning names) where
77+ pure = Pure
78+ (<*>) = Ap
79+
80+
81+projections :: ()
82+ => TableSchema names -> Returning names a -> Maybe (NonEmpty Opaleye.PrimExpr)
83+projections schema@TableSchema {columns} = \case
84+ Pure _ -> Nothing
85+ Ap f a -> projections schema f <> projections schema a
86+ NumberOfRowsAffected -> Nothing
87+ Projection f -> Just (exprs (castTable (f (view columns))))
88+
89+
90+runReturning :: ()
91+ => ((Int64 -> a) -> r)
92+ -> (forall x. Hasql.Row x -> ([x] -> a) -> r)
93+ -> Returning names a
94+ -> r
95+runReturning rowCount rowList = \case
96+ Pure a -> rowCount (const a)
97+ Ap fs as ->
98+ runReturning
99+ (\withCount ->
100+ runReturning
101+ (\withCount' -> rowCount (withCount <*> withCount'))
102+ (\decoder -> rowList decoder . liftA2 withCount length64)
103+ as)
104+ (\decoder withRows ->
105+ runReturning
106+ (\withCount -> rowList decoder $ withRows <*> withCount . length64)
107+ (\decoder' withRows' ->
108+ rowList (liftA2 (,) decoder decoder') $
109+ withRows <$> fmap fst <*> withRows' . fmap snd)
110+ as)
111+ fs
112+ NumberOfRowsAffected -> rowCount id
113+ Projection (_ :: exprs -> returning) -> rowList decoder' id
114+ where
115+ decoder' = parse @returning
116+ where
117+ length64 :: Foldable f => f x -> Int64
118+ length64 = fromIntegral . length
119+
120+
121+decodeReturning :: Returning names a -> Hasql.Result a
122+decodeReturning = runReturning
123+ (<$> Hasql.rowsAffected)
124+ (\decoder withRows -> withRows <$> Hasql.rowList decoder)
125+
126+
127+ppReturning :: TableSchema names -> Returning names a -> Doc
128+ppReturning schema returning = case projections schema returning of
129+ Nothing -> mempty
130+ Just columns ->
131+ text "RETURNING" <+> Opaleye.commaV Opaleye.ppSqlExpr (toList sqlExprs)
132+ where
133+ sqlExprs = Opaleye.sqlExpr <$> columns
src/Rel8/Statement/SQL.hsnew file+29
@@ -0,0 +1,29 @@
1+module Rel8.Statement.SQL
2+ ( showDelete
3+ , showInsert
4+ , showUpdate
5+ )
6+where
7+
8+-- base
9+import Prelude
10+
11+-- rel8
12+import Rel8.Statement.Delete ( Delete, ppDelete )
13+import Rel8.Statement.Insert ( Insert, ppInsert )
14+import Rel8.Statement.Update ( Update, ppUpdate )
15+
16+
17+-- | Convert a 'Delete' to a 'String' containing a @DELETE@ statement.
18+showDelete :: Delete a -> String
19+showDelete = show . ppDelete
20+
21+
22+-- | Convert an 'Insert' to a 'String' containing an @INSERT@ statement.
23+showInsert :: Insert a -> String
24+showInsert = show . ppInsert
25+
26+
27+-- | Convert an 'Update' to a 'String' containing an @UPDATE@ statement.
28+showUpdate :: Update a -> String
29+showUpdate = show . ppUpdate
src/Rel8/Statement/Select.hs+120−35
@@ -1,62 +1,147 @@
1+{-# language DeriveTraversable #-}
2+{-# language DerivingStrategies #-}
3+{-# language FlexibleContexts #-}
14{-# language MonoLocalBinds #-}
25{-# language ScopedTypeVariables #-}
6+{-# language StandaloneKindSignatures #-}
37{-# language TypeApplications #-}
48
59module Rel8.Statement.Select
610 ( select
7− , selectWithNames
11+ , ppSelect
12+
13+ , Optimized(..)
14+ , ppPrimSelect
15+ , ppRows
816 )
917where
1018
1119-- base
12−import Control.Exception ( throwIO )
13−import Prelude
20+import Data.Foldable ( toList )
21+import Data.Kind ( Type )
22+import Data.Void ( Void )
23+import Prelude hiding ( undefined )
1424
1525-- hasql
16−import Hasql.Connection ( Connection )
1726import qualified Hasql.Decoders as Hasql
1827import qualified Hasql.Encoders as Hasql
19−import qualified Hasql.Session as Hasql
2028import qualified Hasql.Statement as Hasql
2129
30+-- opaleye
31+import qualified Opaleye.Internal.HaskellDB.PrimQuery as Opaleye
32+import qualified Opaleye.Internal.HaskellDB.Sql as Opaleye
33+import qualified Opaleye.Internal.HaskellDB.Sql.Print as Opaleye
34+import qualified Opaleye.Internal.PrimQuery as Opaleye
35+import qualified Opaleye.Internal.Print as Opaleye
36+import qualified Opaleye.Internal.Optimize as Opaleye
37+import qualified Opaleye.Internal.QueryArr as Opaleye hiding ( Select )
38+import qualified Opaleye.Internal.Sql as Opaleye hiding ( Values )
39+import qualified Opaleye.Internal.Tag as Opaleye
40+
41+-- pretty
42+import Text.PrettyPrint ( Doc )
43+
2244-- rel8
45+import Rel8.Expr ( Expr )
46+import Rel8.Expr.Bool ( false )
47+import Rel8.Expr.Opaleye ( toPrimExpr )
2348import Rel8.Query ( Query )
24−import Rel8.Query.SQL ( sqlForQuery, sqlForQueryWithNames )
49+import Rel8.Query.Opaleye ( toOpaleye )
2550import Rel8.Schema.Name ( Selects )
51+import Rel8.Table ( Table )
52+import Rel8.Table.Cols ( toCols )
53+import Rel8.Table.Name ( namesFromLabels )
54+import Rel8.Table.Opaleye ( castTable, exprsWithNames )
55+import qualified Rel8.Table.Opaleye as T
2656import Rel8.Table.Serialize ( Serializable, parse )
57+import Rel8.Table.Undefined ( undefined )
2758
2859-- text
2960import qualified Data.Text as Text
3061import Data.Text.Encoding ( encodeUtf8 )
3162
3263
33−-- | Run a @SELECT@ query, returning all rows.
64+-- | Run a @SELECT@ statement, returning all rows.
3465select :: forall exprs a. Serializable exprs a
35− => Connection -> Query exprs -> IO [a]
36−select c query = case sqlForQuery query of
37− Nothing -> pure []
38− Just sql -> Hasql.run session c >>= either throwIO pure
39− where
40− session = Hasql.statement () statement
41− statement = Hasql.Statement bytes params decode prepare
42− bytes = encodeUtf8 (Text.pack sql)
43− params = Hasql.noParams
44− decode = Hasql.rowList (parse @exprs @a)
45− prepare = False
46−
47−
48−selectWithNames :: forall exprs a names.
49− ( Selects names exprs
50− , Serializable exprs a
51− )
52− => Connection -> names -> Query exprs -> IO [a]
53−selectWithNames c names query = case sqlForQueryWithNames names query of
54− Nothing -> pure []
55− Just sql -> Hasql.run session c >>= either throwIO pure
56− where
57− session = Hasql.statement () statement
58− statement = Hasql.Statement bytes params decode prepare
59− bytes = encodeUtf8 (Text.pack sql)
60− params = Hasql.noParams
61− decode = Hasql.rowList (parse @exprs @a)
62− prepare = False
66+ => Query exprs -> Hasql.Statement () [a]
67+select query = Hasql.Statement bytes params decode prepare
68+ where
69+ bytes = encodeUtf8 (Text.pack sql)
70+ params = Hasql.noParams
71+ decode = Hasql.rowList (parse @exprs @a)
72+ prepare = False
73+ sql = show doc
74+ doc = ppSelect query
75+
76+
77+ppSelect :: Table Expr a => Query a -> Doc
78+ppSelect query =
79+ Opaleye.ppSql $ primSelectWith names (toCols exprs') primQuery'
80+ where
81+ names = namesFromLabels
82+ (exprs, primQuery, _) =
83+ Opaleye.runSimpleQueryArrStart (toOpaleye query) ()
84+ (exprs', primQuery') = case optimize primQuery of
85+ Empty -> (undefined, Opaleye.Product (pure (pure Opaleye.Unit)) never)
86+ Unit -> (exprs, Opaleye.Unit)
87+ Optimized pq -> (exprs, pq)
88+ never = pure (toPrimExpr false)
89+
90+
91+ppRows :: Table Expr a => Query a -> Doc
92+ppRows query = case optimize primQuery of
93+ -- Special case VALUES because we can't use DEFAULT inside a SELECT
94+ Optimized (Opaleye.Values symbols rows)
95+ | eqSymbols symbols (toList (T.exprs a)) ->
96+ Opaleye.ppValues_ (map Opaleye.sqlExpr <$> toList rows)
97+ _ -> ppSelect query
98+ where
99+ (a, primQuery, _) = Opaleye.runSimpleQueryArrStart (toOpaleye query) ()
100+
101+ eqSymbols (symbol : symbols) (Opaleye.AttrExpr symbol' : exprs)
102+ | eqSymbol symbol symbol' = eqSymbols symbols exprs
103+ | otherwise = False
104+ eqSymbols [] [] = True
105+ eqSymbols _ _ = False
106+
107+ eqSymbol
108+ (Opaleye.Symbol name (Opaleye.UnsafeTag tag))
109+ (Opaleye.Symbol name' (Opaleye.UnsafeTag tag'))
110+ = name == name' && tag == tag'
111+
112+
113+ppPrimSelect :: Query a -> (Optimized Doc, a)
114+ppPrimSelect query =
115+ (Opaleye.ppSql . primSelect <$> optimize primQuery, a)
116+ where
117+ (a, primQuery, _) = Opaleye.runSimpleQueryArrStart (toOpaleye query) ()
118+
119+
120+type Optimized :: Type -> Type
121+data Optimized a = Empty | Unit | Optimized a
122+ deriving stock (Functor, Foldable, Traversable, Show)
123+
124+
125+optimize :: Opaleye.PrimQuery' a -> Optimized (Opaleye.PrimQuery' Void)
126+optimize query = case Opaleye.removeEmpty (Opaleye.optimize query) of
127+ Nothing -> Empty
128+ Just Opaleye.Unit -> Unit
129+ Just query' -> Optimized query'
130+
131+
132+primSelect :: Opaleye.PrimQuery' Void -> Opaleye.Select
133+primSelect = Opaleye.foldPrimQuery Opaleye.sqlQueryGenerator
134+
135+
136+primSelectWith :: Selects names exprs
137+ => names -> exprs -> Opaleye.PrimQuery' Void -> Opaleye.Select
138+primSelectWith names exprs query =
139+ Opaleye.SelectFrom $ Opaleye.newSelect
140+ { Opaleye.attrs = Opaleye.SelectAttrs attrs
141+ , Opaleye.tables = Opaleye.oneTable (primSelect query)
142+ }
143+ where
144+ attrs = makeAttr <$> exprsWithNames names (castTable exprs)
145+ where
146+ makeAttr (label, expr) =
147+ (Opaleye.sqlExpr expr, Just (Opaleye.SqlColumn label))
src/Rel8/Statement/Set.hsnew file+33
@@ -0,0 +1,33 @@
1+{-# language MonoLocalBinds #-}
2+{-# language NamedFieldPuns #-}
3+
4+module Rel8.Statement.Set
5+ ( ppSet
6+ )
7+where
8+
9+-- base
10+import Data.Foldable ( toList )
11+import Prelude ()
12+
13+-- opaleye
14+import qualified Opaleye.Internal.HaskellDB.Sql.Print as Opaleye
15+import qualified Opaleye.Internal.Sql as Opaleye
16+
17+-- pretty
18+import Text.PrettyPrint ( Doc, (<+>), equals, text )
19+
20+-- rel8
21+import Rel8.Schema.Name ( Selects, ppColumn )
22+import Rel8.Schema.Table ( TableSchema(..) )
23+import Rel8.Table.Opaleye ( attributes, exprsWithNames )
24+
25+
26+ppSet :: Selects names exprs
27+ => TableSchema names -> (exprs -> exprs) -> Doc
28+ppSet schema@TableSchema {columns} f =
29+ text "SET" <+> Opaleye.commaV ppAssign (toList assigns)
30+ where
31+ assigns = exprsWithNames columns (f (attributes schema))
32+ ppAssign (column, expr) =
33+ ppColumn column <+> equals <+> Opaleye.ppSqlExpr (Opaleye.sqlExpr expr)
src/Rel8/Statement/Update.hs+38−60
@@ -1,43 +1,37 @@
1+{-# language DuplicateRecordFields #-}
12{-# language GADTs #-}
23{-# language NamedFieldPuns #-}
3−{-# language ScopedTypeVariables #-}
4+{-# language RecordWildCards #-}
45{-# language StandaloneKindSignatures #-}
5−{-# language TypeApplications #-}
6+{-# language StrictData #-}
67
78module Rel8.Statement.Update
89 ( Update(..)
910 , update
11+ , ppUpdate
1012 )
1113where
1214
1315-- base
14−import Control.Exception ( throwIO )
1516import Data.Kind ( Type )
1617import Prelude
1718
1819-- hasql
19−import Hasql.Connection ( Connection )
20−import qualified Hasql.Decoders as Hasql
2120import qualified Hasql.Encoders as Hasql
22−import qualified Hasql.Session as Hasql
2321import qualified Hasql.Statement as Hasql
2422
25−-- opaleye
26−import qualified Opaleye.Internal.Manipulation as Opaleye
27−
28−-- profunctors
29−import Data.Profunctor ( lmap )
23+-- pretty
24+import Text.PrettyPrint ( Doc, (<+>), ($$), text )
3025
3126-- rel8
3227import Rel8.Expr ( Expr )
33−import Rel8.Expr.Opaleye ( toColumn, toPrimExpr )
28+import Rel8.Query ( Query )
3429import Rel8.Schema.Name ( Selects )
35−import Rel8.Schema.Table ( TableSchema )
36−import Rel8.Statement.Returning ( Returning( Projection, NumberOfRowsAffected ) )
37−import Rel8.Table ( fromColumns, toColumns )
38−import Rel8.Table.Insert ( toInsert )
39−import Rel8.Table.Opaleye ( castTable, table, unpackspec )
40−import Rel8.Table.Serialize ( Serializable, parse )
30+import Rel8.Schema.Table ( TableSchema(..), ppTable )
31+import Rel8.Statement.Returning ( Returning, decodeReturning, ppReturning )
32+import Rel8.Statement.Set ( ppSet )
33+import Rel8.Statement.Using ( ppFrom )
34+import Rel8.Statement.Where ( ppWhere )
4135
4236-- text
4337import qualified Data.Text as Text
@@ -50,9 +44,12 @@ data Update a where
5044 Update :: Selects names exprs =>
5145 { target :: TableSchema names
5246 -- ^ Which table to update.
53− , set :: exprs -> exprs
47+ , from :: Query from
48+ -- ^ @FROM@ clause — this can be used to join against other tables,
49+ -- and its results can be referenced in the @SET@ and @WHERE@ clauses.
50+ , set :: from -> exprs -> exprs
5451 -- ^ How to update each selected row.
55− , updateWhere :: exprs -> Expr Bool
52+ , updateWhere :: from -> exprs -> Expr Bool
5653 -- ^ Which rows to select for update.
5754 , returning :: Returning names a
5855 -- ^ What to return from the @UPDATE@ statement.
@@ -60,46 +57,27 @@ data Update a where
6057 -> Update a
6158
6259
63−-- | Run an @UPDATE@ statement.
64−update :: Connection -> Update a -> IO a
65−update c Update {target, set, updateWhere, returning} =
66− case returning of
67− NumberOfRowsAffected -> Hasql.run session c >>= either throwIO pure
68− where
69− session = Hasql.statement () statement
70− statement = Hasql.Statement bytes params decode prepare
71− bytes = encodeUtf8 $ Text.pack sql
72− params = Hasql.noParams
73− decode = Hasql.rowsAffected
74− prepare = False
75− sql = Opaleye.arrangeUpdateSql target' set' where'
76− where
77− target' = lmap toInsert $ table $ toColumns <$> target
78− set' = toColumns . set . fromColumns
79− where' = toColumn . toPrimExpr . updateWhere . fromColumns
60+ppUpdate :: Update a -> Doc
61+ppUpdate Update {..} = case ppFrom from of
62+ Nothing ->
63+ text "UPDATE" <+> ppTable target $$
64+ ppSet target id $$
65+ text "WHERE false"
66+ Just (fromDoc, i) ->
67+ text "UPDATE" <+> ppTable target $$
68+ ppSet target (set i) $$
69+ fromDoc $$
70+ ppWhere target (updateWhere i) $$
71+ ppReturning target returning
8072
81− Projection project -> Hasql.run session c >>= either throwIO pure
82− where
83− session = Hasql.statement () statement
84− statement = Hasql.Statement bytes params decode prepare
85− bytes = encodeUtf8 $ Text.pack sql
86− params = Hasql.noParams
87− decode = decoder project
88− prepare = False
89− sql =
90− Opaleye.arrangeUpdateReturningSql
91− unpackspec
92− target'
93− set'
94− where'
95− project'
96− where
97− target' = lmap toInsert $ table $ toColumns <$> target
98− set' = toColumns . set . fromColumns
99− where' = toColumn . toPrimExpr . updateWhere . fromColumns
100− project' = castTable . toColumns . project . fromColumns
10173
74+-- | Run an @UPDATE@ statement.
75+update :: Update a -> Hasql.Statement () a
76+update u@Update {returning} = Hasql.Statement bytes params decode prepare
10277 where
103− decoder :: forall exprs projection a. Serializable projection a
104− => (exprs -> projection) -> Hasql.Result [a]
105− decoder _ = Hasql.rowList (parse @projection @a)
78+ bytes = encodeUtf8 $ Text.pack sql
79+ params = Hasql.noParams
80+ decode = decodeReturning returning
81+ prepare = False
82+ sql = show doc
83+ doc = ppUpdate u
src/Rel8/Statement/Using.hsnew file+36
@@ -0,0 +1,36 @@
1+module Rel8.Statement.Using
2+ ( ppFrom
3+ , ppUsing
4+ )
5+where
6+
7+-- base
8+import Prelude
9+
10+-- pretty
11+import Text.PrettyPrint ( Doc, (<+>), parens, text )
12+
13+-- rel8
14+import Rel8.Query ( Query )
15+import Rel8.Schema.Table ( TableSchema(..), ppTable )
16+import Rel8.Statement.Select ( Optimized(..), ppPrimSelect )
17+
18+
19+ppFrom :: Query a -> Maybe (Doc, a)
20+ppFrom = ppJoin "FROM"
21+
22+
23+ppUsing :: Query a -> Maybe (Doc, a)
24+ppUsing = ppJoin "USING"
25+
26+
27+ppJoin :: String -> Query a -> Maybe (Doc, a)
28+ppJoin clause join = do
29+ doc <- case ofrom of
30+ Empty -> Nothing
31+ Unit -> Just mempty
32+ Optimized doc -> Just $ text clause <+> parens doc <+> ppTable alias
33+ pure (doc, a)
34+ where
35+ alias = TableSchema {name = "T1", schema = Nothing, columns = ()}
36+ (ofrom, a) = ppPrimSelect join
src/Rel8/Statement/View.hs+43−28
@@ -3,61 +3,76 @@
33
44module Rel8.Statement.View
55 ( createView
6+ , createOrReplaceView
67 )
78where
89
910-- base
10−import Control.Exception ( throwIO )
11−import Control.Monad ( (>=>) )
12−import Data.Foldable ( fold )
13−import Data.Maybe ( fromMaybe )
1411import Prelude
1512
1613-- hasql
17−import Hasql.Connection ( Connection )
1814import qualified Hasql.Decoders as Hasql
1915import qualified Hasql.Encoders as Hasql
20−import qualified Hasql.Session as Hasql
2116import qualified Hasql.Statement as Hasql
2217
2318-- rel8
2419import Rel8.Query ( Query )
25−import Rel8.Query.SQL ( sqlForQueryWithNames )
2620import Rel8.Schema.Name ( Selects )
27−import Rel8.Schema.Table ( TableSchema( TableSchema ) )
28−import Rel8.Table.Alternative ( emptyTable )
21+import Rel8.Schema.Table ( TableSchema )
22+import Rel8.Statement.Insert ( ppInto )
23+import Rel8.Statement.Select ( ppSelect )
24+
25+-- pretty
26+import Text.PrettyPrint ( Doc, (<+>), ($$), text )
2927
3028-- text
3129import qualified Data.Text as Text
3230import Data.Text.Encoding ( encodeUtf8 )
3331
3432
33+data CreateView = Create | CreateOrReplace
34+
35+
3536-- | Given a 'TableSchema' and 'Query', @createView@ runs a @CREATE VIEW@
3637-- statement that will save the given query as a view. This can be useful if
3738-- you want to share Rel8 queries with other applications.
3839createView :: Selects names exprs
39− => TableSchema names -> Query exprs -> Connection -> IO ()
40−createView (TableSchema name mschema names) query =
41− Hasql.run session >=> either throwIO pure
40+ => TableSchema names -> Query exprs -> Hasql.Statement () ()
41+createView =
42+ createViewGeneric Create
43+
44+
45+-- | Given a 'TableSchema' and 'Query', @createOrReplaceView@ runs a
46+-- @CREATE OR REPLACE VIEW@ statement that will save the given query
47+-- as a view, replacing the current view definition if it exists and
48+-- adheres to the restrictions in place for replacing a view in
49+-- PostgreSQL.
50+createOrReplaceView :: Selects names exprs
51+ => TableSchema names -> Query exprs -> Hasql.Statement () ()
52+createOrReplaceView =
53+ createViewGeneric CreateOrReplace
54+
55+
56+createViewGeneric :: Selects names exprs
57+ => CreateView -> TableSchema names -> Query exprs -> Hasql.Statement () ()
58+createViewGeneric replace schema query =
59+ Hasql.Statement bytes params decode prepare
4260 where
43− session = Hasql.statement () statement
44− statement = Hasql.Statement bytes params decode prepare
4561 bytes = encodeUtf8 (Text.pack sql)
4662 params = Hasql.noParams
4763 decode = Hasql.noResult
4864 prepare = False
49− sql = "CREATE VIEW " <> title <> " AS " <> select
50− where
51− title = case mschema of
52− Nothing -> quote name
53− Just schema -> quote schema <> "." <> quote name
54− select = fromMaybe fallback $ sqlForQueryWithNames names query
55− where
56− fallback = fold $ sqlForQueryWithNames names emptyTable
57−
58−
59−quote :: String -> String
60−quote string = "\"" <> concatMap go string <> "\""
65+ sql = show doc
66+ doc = ppCreateView schema query replace
67+
68+
69+ppCreateView :: Selects names exprs
70+ => TableSchema names -> Query exprs -> CreateView -> Doc
71+ppCreateView schema query replace =
72+ createOrReplace replace <+>
73+ ppInto schema $$
74+ text "AS" <+>
75+ ppSelect query
6176 where
62− go '"' = "\"\""
63− go c = [c]
77+ createOrReplace Create = text "CREATE VIEW"
78+ createOrReplace CreateOrReplace = text "CREATE OR REPLACE VIEW"
src/Rel8/Statement/Where.hsnew file+31
@@ -0,0 +1,31 @@
1+{-# language MonoLocalBinds #-}
2+
3+module Rel8.Statement.Where
4+ ( ppWhere
5+ )
6+where
7+
8+-- base
9+import Prelude
10+
11+-- opaleye
12+import qualified Opaleye.Internal.HaskellDB.Sql.Print as Opaleye
13+import qualified Opaleye.Internal.Sql as Opaleye
14+
15+-- pretty
16+import Text.PrettyPrint ( Doc, (<+>), text )
17+
18+-- rel8
19+import Rel8.Expr ( Expr )
20+import Rel8.Expr.Opaleye ( toPrimExpr )
21+import Rel8.Schema.Name ( Selects )
22+import Rel8.Schema.Table ( TableSchema )
23+import Rel8.Table.Opaleye ( attributes )
24+
25+
26+ppWhere :: Selects names exprs
27+ => TableSchema names -> (exprs -> Expr Bool) -> Doc
28+ppWhere schema where_ = text "WHERE" <+> ppExpr condition
29+ where
30+ ppExpr = Opaleye.ppSqlExpr . Opaleye.sqlExpr . toPrimExpr
31+ condition = where_ (attributes schema)
src/Rel8/Table.hs+95−206
@@ -1,62 +1,47 @@
1+{-# language AllowAmbiguousTypes #-}
12{-# language DataKinds #-}
23{-# language DefaultSignatures #-}
3−{-# language DisambiguateRecordFields #-}
44{-# language FlexibleContexts #-}
55{-# language FlexibleInstances #-}
66{-# language FunctionalDependencies #-}
7−{-# language LambdaCase #-}
8−{-# language NamedFieldPuns #-}
97{-# language ScopedTypeVariables #-}
108{-# language StandaloneKindSignatures #-}
119{-# language TypeApplications #-}
1210{-# language TypeFamilies #-}
13−{-# language TypeOperators #-}
1411{-# language UndecidableInstances #-}
1512
1613module Rel8.Table
17− ( Table (Columns, Context, toColumns, fromColumns)
14+ ( Table
15+ ( Columns, Context, fromColumns, toColumns
16+ , FromExprs, fromResult, toResult
17+ , Transpose
18+ )
1819 , Congruent
19− , TTable, TColumns, TContext
20+ , TTable, TColumns, TContext, TFromExprs, TTranspose
21+ , TSerialize
2022 )
2123where
2224
2325-- base
24−import Data.Functor ( ($>) )
2526import Data.Functor.Identity ( Identity( Identity ) )
2627import Data.Kind ( Constraint, Type )
27−import Data.List.NonEmpty ( NonEmpty )
2828import GHC.Generics ( Generic, Rep, from, to )
2929import Prelude hiding ( null )
3030
3131-- rel8
3232import Rel8.FCF ( Eval, Exp )
33−import Rel8.Generic.Table
34− ( GTable, GColumns, GContext, fromGColumns, toGColumns
33+import Rel8.Generic.Map ( Map )
34+import Rel8.Generic.Table.Record
35+ ( GTable, GColumns, GContext, gfromColumns, gtoColumns
36+ , GSerialize, gfromResult, gtoResult
3537 )
3638import Rel8.Generic.Record ( Record(..) )
37−import Rel8.Schema.Context ( Col(..) )
38−import Rel8.Schema.Context.Label ( Labelable, labeler, unlabeler )
3939import Rel8.Schema.HTable ( HTable )
40−import Rel8.Schema.HTable.Either ( HEitherTable(..) )
41−import Rel8.Schema.HTable.Identity ( HIdentity(..) )
42−import Rel8.Schema.HTable.Label ( hlabel, hunlabel )
43−import Rel8.Schema.HTable.List ( HListTable )
44−import Rel8.Schema.HTable.Maybe ( HMaybeTable(..) )
45−import Rel8.Schema.HTable.NonEmpty ( HNonEmptyTable )
46−import Rel8.Schema.HTable.Nullify ( hnulls, hnullify, hunnullify )
47−import Rel8.Schema.HTable.These ( HTheseTable(..) )
48−import Rel8.Schema.HTable.Type ( HType( HType ) )
49−import Rel8.Schema.HTable.Vectorize ( hvectorize, hunvectorize )
40+import Rel8.Schema.HTable.Identity ( HIdentity( HIdentity ) )
5041import qualified Rel8.Schema.Kind as K
51−import Rel8.Schema.Null ( Nullify, Nullity( Null, NotNull ), Sql )
42+import Rel8.Schema.Null ( Sql )
5243import Rel8.Schema.Result ( Result )
53−import Rel8.Schema.Spec ( Spec( Spec ), SSpec(..), KnownSpec )
5444import Rel8.Type ( DBType )
55−import Rel8.Type.Tag ( EitherTag( IsLeft, IsRight ), MaybeTag( IsJust ) )
56−
57−-- these
58−import Data.These ( These( This, That, These ) )
59−import Data.These.Combinators ( justHere, justThere )
6045
6146
6247-- | @Table@s are one of the foundational elements of Rel8, and describe data
@@ -71,40 +56,102 @@ import Data.These.Combinators ( justHere, justThere )
7156-- yourself, as anything that's an instance of 'Rel8.Rel8able' is always a
7257-- 'Table'.
7358type Table :: K.Context -> Type -> Constraint
74−class (HTable (Columns a), context ~ Context a) => Table context a | a -> context where
59+class
60+ ( HTable (Columns a)
61+ , context ~ Context a
62+ , a ~ Transpose context a
63+ )
64+ => Table context a | a -> context
65+ where
7566 -- | The 'HTable' functor that describes the schema of this table.
7667 type Columns a :: K.HTable
7768
7869 -- | The common context that all columns use as an interpretation.
7970 type Context a :: K.Context
8071
81− toColumns :: a -> Columns a (Col (Context a))
82− fromColumns :: Columns a (Col (Context a)) -> a
72+ -- | The @FromExprs@ type family maps a type in the @Expr@ context to the
73+ -- corresponding Haskell type.
74+ type FromExprs a :: Type
75+
76+ type Transpose (context' :: K.Context) a :: Type
77+
78+
79+ toColumns :: a -> Columns a context
80+ fromColumns :: Columns a context -> a
81+
82+ fromResult :: Columns a Result -> FromExprs a
83+ toResult :: FromExprs a -> Columns a Result
8384
8485 type Columns a = GColumns TColumns (Rep (Record a))
8586 type Context a = GContext TContext (Rep (Record a))
87+ type FromExprs a = Map TFromExprs a
88+ type Transpose context a = Map (TTranspose context) a
8689
8790 default toColumns ::
8891 ( Generic (Record a)
89− , GTable (TTable context) TColumns (Col (Context a)) (Rep (Record a))
92+ , GTable (TTable context) TColumns (Rep (Record a))
9093 , Columns a ~ GColumns TColumns (Rep (Record a))
9194 )
92− => a -> Columns a (Col (Context a))
95+ => a -> Columns a context
9396 toColumns =
94− toGColumns @(TTable context) @TColumns toColumns .
97+ gtoColumns @(TTable context) @TColumns toColumns .
9598 from .
9699 Record
97100
98101 default fromColumns ::
99102 ( Generic (Record a)
100− , GTable (TTable context) TColumns (Col (Context a)) (Rep (Record a))
103+ , GTable (TTable context) TColumns (Rep (Record a))
101104 , Columns a ~ GColumns TColumns (Rep (Record a))
102105 )
103− => Columns a (Col (Context a)) -> a
106+ => Columns a context -> a
104107 fromColumns =
105108 unrecord .
106109 to .
107− fromGColumns @(TTable context) @TColumns fromColumns
110+ gfromColumns @(TTable context) @TColumns fromColumns
111+
112+ default toResult ::
113+ ( Generic (Record (FromExprs a))
114+ , GSerialize TSerialize TColumns (Rep (Record a)) (Rep (Record (FromExprs a)))
115+ , Columns a ~ GColumns TColumns (Rep (Record a))
116+ )
117+ => FromExprs a -> Columns a Result
118+ toResult =
119+ gtoResult
120+ @TSerialize
121+ @TColumns
122+ @(Rep (Record a))
123+ @(Rep (Record (FromExprs a)))
124+ (\(_ :: proxy x) -> toResult @(Context x) @x) .
125+ from .
126+ Record
127+
128+ default fromResult ::
129+ ( Generic (Record (FromExprs a))
130+ , GSerialize TSerialize TColumns (Rep (Record a)) (Rep (Record (FromExprs a)))
131+ , Columns a ~ GColumns TColumns (Rep (Record a))
132+ )
133+ => Columns a Result -> FromExprs a
134+ fromResult =
135+ unrecord .
136+ to .
137+ gfromResult
138+ @TSerialize
139+ @TColumns
140+ @(Rep (Record a))
141+ @(Rep (Record (FromExprs a)))
142+ (\(_ :: proxy x) -> fromResult @(Context x) @x)
143+
144+
145+instance Sql DBType a => Table Result (Identity a) where
146+ type Columns (Identity a) = HIdentity a
147+ type Context (Identity a) = Result
148+ type FromExprs (Identity a) = a
149+ type Transpose to (Identity a) = to a
150+
151+ toColumns = HIdentity
152+ fromColumns (HIdentity a) = a
153+ toResult a = HIdentity (Identity a)
154+ fromResult (HIdentity (Identity a)) = a
108155
109156
110157data TTable :: K.Context -> Type -> Exp Constraint
@@ -119,144 +166,32 @@ data TContext :: Type -> Exp K.Context
119166type instance Eval (TContext a) = Context a
120167
121168
122−-- | Any 'HTable' is also a 'Table'.
123−instance HTable t => Table context (t (Col context)) where
124− type Columns (t (Col context)) = t
125− type Context (t (Col context)) = context
169+data TFromExprs :: Type -> Exp Type
170+type instance Eval (TFromExprs a) = FromExprs a
126171
127− toColumns = id
128− fromColumns = id
129172
173+data TTranspose :: K.Context -> Type -> Exp Type
174+type instance Eval (TTranspose context a) = Transpose context a
130175
131−-- | Any context is trivially a table.
132−instance KnownSpec spec => Table context (Col context spec) where
133− type Columns (Col context spec) = HIdentity spec
134− type Context (Col context spec) = context
135−
136− toColumns = HIdentity
137− fromColumns = unHIdentity
138176
177+data TSerialize :: Type -> Type -> Exp Constraint
178+type instance Eval (TSerialize expr a) =
179+ ( Table (Context expr) expr
180+ , a ~ FromExprs expr
181+ )
139182
140−instance Sql DBType a => Table Result (Identity a) where
141− type Columns (Identity a) = HType a
142− type Context (Identity a) = Result
143183
144− toColumns (Identity a) = HType (Result a)
145− fromColumns (HType (Result a)) = Identity a
146−
147−
148−instance (Table Result a, Table Result b) => Table Result (Either a b) where
149− type Columns (Either a b) = HEitherTable (Columns a) (Columns b)
150− type Context (Either a b) = Result
151−
152− toColumns = \case
153− Left table -> HEitherTable
154− { htag = HIdentity (Result IsLeft)
155− , hleft = hlabel labeler (hnullify nullifier (toColumns table))
156− , hright = hlabel labeler (hnulls null)
157− }
158− Right table -> HEitherTable
159− { htag = HIdentity (Result IsRight)
160− , hleft = hlabel labeler (hnulls null)
161− , hright = hlabel labeler (hnullify nullifier (toColumns table))
162− }
163−
164− fromColumns HEitherTable {htag, hleft, hright} = case htag of
165− HIdentity (Result tag) -> case tag of
166− IsLeft -> maybe err (Left . fromColumns) $ hunnullify unnullifier (hunlabel unlabeler hleft)
167− IsRight -> maybe err (Right . fromColumns) $ hunnullify unnullifier (hunlabel unlabeler hright)
168− where
169− err = error "Either.fromColumns: mismatch between tag and data"
170−
171−
172−instance Table Result a => Table Result [a] where
173− type Columns [a] = HListTable (Columns a)
174− type Context [a] = Result
175−
176− toColumns = hvectorize vectorizer . fmap toColumns
177− fromColumns = fmap fromColumns . hunvectorize unvectorizer
178−
179−
180−instance Table Result a => Table Result (Maybe a) where
181− type Columns (Maybe a) = HMaybeTable (Columns a)
182− type Context (Maybe a) = Result
183−
184− toColumns = \case
185− Nothing -> HMaybeTable
186− { htag = HIdentity (Result Nothing)
187− , hjust = hlabel labeler (hnulls null)
188− }
189− Just table -> HMaybeTable
190− { htag = HIdentity (Result (Just IsJust))
191− , hjust = hlabel labeler (hnullify nullifier (toColumns table))
192− }
193−
194− fromColumns HMaybeTable {htag, hjust} = case htag of
195− HIdentity (Result tag) -> tag $>
196− case hunnullify unnullifier (hunlabel unlabeler hjust) of
197− Nothing -> error "Maybe.fromColumns: mismatch between tag and data"
198− Just just -> fromColumns just
199−
200−
201−instance Table Result a => Table Result (NonEmpty a) where
202− type Columns (NonEmpty a) = HNonEmptyTable (Columns a)
203− type Context (NonEmpty a) = Result
204−
205− toColumns = hvectorize vectorizer . fmap toColumns
206− fromColumns = fmap fromColumns . hunvectorize unvectorizer
207−
208−
209−instance (Table Result a, Table Result b) => Table Result (These a b) where
210− type Columns (These a b) = HTheseTable (Columns a) (Columns b)
211− type Context (These a b) = Result
212−
213− toColumns tables = HTheseTable
214− { hhereTag = relabel hhereTag
215− , hhere = hlabel labeler (hunlabel unlabeler (toColumns hhere))
216− , hthereTag = relabel hthereTag
217− , hthere = hlabel labeler (hunlabel unlabeler (toColumns hthere))
218− }
219− where
220− HMaybeTable
221− { htag = hhereTag
222− , hjust = hhere
223− } = toColumns (justHere tables)
224− HMaybeTable
225− { htag = hthereTag
226− , hjust = hthere
227− } = toColumns (justThere tables)
228−
229− fromColumns HTheseTable {hhereTag, hhere, hthereTag, hthere} =
230− case (fromColumns mhere, fromColumns mthere) of
231− (Just a, Nothing) -> This (fromColumns a)
232− (Nothing, Just b) -> That (fromColumns b)
233− (Just a, Just b) -> These (fromColumns a) (fromColumns b)
234− _ -> error "These.fromColumns: mismatch between tags and data"
235− where
236− mhere = HMaybeTable
237− { htag = relabel hhereTag
238− , hjust = hlabel labeler (hunlabel unlabeler hhere)
239− }
240− mthere = HMaybeTable
241− { htag = relabel hthereTag
242− , hjust = hlabel labeler (hunlabel unlabeler hthere)
243− }
244−
245−
246−instance (Table context a, Table context b, Labelable context)
247− => Table context (a, b)
184+instance (Table context a, Table context b) => Table context (a, b)
248185
249186
250187instance
251188 ( Table context a, Table context b, Table context c
252− , Labelable context
253189 )
254190 => Table context (a, b, c)
255191
256192
257193instance
258194 ( Table context a, Table context b, Table context c, Table context d
259− , Labelable context
260195 )
261196 => Table context (a, b, c, d)
262197
@@ -264,7 +199,6 @@ instance
264199instance
265200 ( Table context a, Table context b, Table context c, Table context d
266201 , Table context e
267− , Labelable context
268202 )
269203 => Table context (a, b, c, d, e)
270204
@@ -272,7 +206,6 @@ instance
272206instance
273207 ( Table context a, Table context b, Table context c, Table context d
274208 , Table context e, Table context f
275− , Labelable context
276209 )
277210 => Table context (a, b, c, d, e, f)
278211
@@ -280,7 +213,6 @@ instance
280213instance
281214 ( Table context a, Table context b, Table context c, Table context d
282215 , Table context e, Table context f, Table context g
283− , Labelable context
284216 )
285217 => Table context (a, b, c, d, e, f, g)
286218
@@ -288,46 +220,3 @@ instance
288220type Congruent :: Type -> Type -> Constraint
289221class Columns a ~ Columns b => Congruent a b
290222instance Columns a ~ Columns b => Congruent a b
291−
292−
293−null :: Col Result ('Spec labels necessity (Maybe a))
294−null = Result Nothing
295−
296−
297−nullifier :: ()
298− => SSpec ('Spec labels necessity a)
299− -> Col Result ('Spec labels necessity a)
300− -> Col Result ('Spec labels necessity (Nullify a))
301−nullifier SSpec {nullity} (Result a) = Result $ case nullity of
302− Null -> a
303− NotNull -> Just a
304−
305−
306−unnullifier :: ()
307− => SSpec ('Spec labels necessity a)
308− -> Col Result ('Spec labels necessity (Nullify a))
309− -> Maybe (Col Result ('Spec labels necessity a))
310−unnullifier SSpec {nullity} (Result a) =
311− case nullity of
312− Null -> pure $ Result a
313− NotNull -> Result <$> a
314−
315−
316−vectorizer :: Functor f
317− => SSpec ('Spec labels necessity a)
318− -> f (Col Result ('Spec labels necessity a))
319− -> Col Result ('Spec labels necessity (f a))
320−vectorizer _ = Result . fmap (\(Result a) -> a)
321−
322−
323−unvectorizer :: Functor f
324− => SSpec ('Spec labels necessity a)
325− -> Col Result ('Spec labels necessity (f a))
326− -> f (Col Result ('Spec labels necessity a))
327−unvectorizer _ (Result results) = Result <$> results
328−
329−
330−relabel :: ()
331− => HIdentity ('Spec labels necessity a) (Col Result)
332− -> HIdentity ('Spec relabels necessity a) (Col Result)
333−relabel (HIdentity (Result a)) = HIdentity (Result a)
src/Rel8/Table/ADT.hsnew file+173
@@ -0,0 +1,173 @@
1+{-# language AllowAmbiguousTypes #-}
2+{-# language DataKinds #-}
3+{-# language FlexibleContexts #-}
4+{-# language FlexibleInstances #-}
5+{-# language MultiParamTypeClasses #-}
6+{-# language RankNTypes #-}
7+{-# language ScopedTypeVariables #-}
8+{-# language StandaloneKindSignatures #-}
9+{-# language TypeApplications #-}
10+{-# language TypeFamilyDependencies #-}
11+{-# language UndecidableInstances #-}
12+{-# language UndecidableSuperClasses #-}
13+
14+module Rel8.Table.ADT
15+ ( ADT( ADT )
16+ , ADTable
17+ , BuildableADT
18+ , BuildADT, buildADT
19+ , ConstructableADT
20+ , ConstructADT, constructADT
21+ , DeconstructADT, deconstructADT
22+ , NameADT, nameADT
23+ , AggregateADT, aggregateADT
24+ , ADTRep
25+ )
26+where
27+
28+-- base
29+import Data.Kind ( Constraint, Type )
30+import GHC.Generics ( Generic, from, to )
31+import GHC.TypeLits ( Symbol )
32+import Prelude
33+
34+-- rel8
35+import Rel8.Aggregate ( Aggregate )
36+import Rel8.Expr ( Expr )
37+import Rel8.FCF ( Eval, Exp )
38+import Rel8.Generic.Construction
39+ ( GGBuildable
40+ , GGBuild, ggbuild
41+ , GGConstructable
42+ , GGConstruct, ggconstruct
43+ , GGDeconstruct, ggdeconstruct
44+ , GGName, ggname
45+ , GGAggregate, ggaggregate
46+ )
47+import Rel8.Generic.Record ( Record( Record ), unrecord )
48+import Rel8.Generic.Rel8able
49+ ( Rel8able
50+ , GRep, GColumns, gfromColumns, gtoColumns
51+ , GFromExprs, gfromResult, gtoResult
52+ , TSerialize, deserialize, serialize
53+ )
54+import qualified Rel8.Generic.Table.ADT as G
55+import qualified Rel8.Kind.Algebra as K
56+import Rel8.Schema.HTable ( HTable )
57+import qualified Rel8.Schema.Kind as K
58+import Rel8.Schema.Name ( Name )
59+import Rel8.Schema.Result ( Result )
60+import Rel8.Table ( Table, TColumns )
61+
62+
63+type ADT :: K.Rel8able -> K.Rel8able
64+newtype ADT t context = ADT (GColumnsADT t context)
65+
66+
67+instance ADTable t => Rel8able (ADT t) where
68+ type GColumns (ADT t) = GColumnsADT t
69+ type GFromExprs (ADT t) = t Result
70+
71+ gfromColumns _ = ADT
72+ gtoColumns _ (ADT a) = a
73+
74+ gfromResult =
75+ unrecord .
76+ to .
77+ G.gfromResultADT
78+ @TSerialize
79+ @TColumns
80+ @(Eval (ADTRep t Expr))
81+ @(Eval (ADTRep t Result))
82+ (\(_ :: proxy x) -> deserialize @_ @x)
83+
84+ gtoResult =
85+ G.gtoResultADT
86+ @TSerialize
87+ @TColumns
88+ @(Eval (ADTRep t Expr))
89+ @(Eval (ADTRep t Result))
90+ (\(_ :: proxy x) -> serialize @_ @x) .
91+ from .
92+ Record
93+
94+
95+type ADTable :: K.Rel8able -> Constraint
96+class
97+ ( Generic (Record (t Result))
98+ , HTable (GColumnsADT t)
99+ , G.GSerializeADT TSerialize TColumns (Eval (ADTRep t Expr)) (Eval (ADTRep t Result))
100+ )
101+ => ADTable t
102+instance
103+ ( Generic (Record (t Result))
104+ , HTable (GColumnsADT t)
105+ , G.GSerializeADT TSerialize TColumns (Eval (ADTRep t Expr)) (Eval (ADTRep t Result))
106+ )
107+ => ADTable t
108+
109+
110+type BuildableADT :: K.Rel8able -> Symbol -> Constraint
111+class GGBuildable 'K.Sum name (ADTRep t) => BuildableADT t name
112+instance GGBuildable 'K.Sum name (ADTRep t) => BuildableADT t name
113+
114+
115+type BuildADT :: K.Rel8able -> Symbol -> Type
116+type BuildADT t name = GGBuild 'K.Sum name (ADTRep t) (ADT t Expr)
117+
118+
119+buildADT :: forall t name. BuildableADT t name => BuildADT t name
120+buildADT =
121+ ggbuild @'K.Sum @name @(ADTRep t) @(ADT t Expr) ADT
122+
123+
124+type ConstructableADT :: K.Rel8able -> Constraint
125+class GGConstructable 'K.Sum (ADTRep t) => ConstructableADT t
126+instance GGConstructable 'K.Sum (ADTRep t) => ConstructableADT t
127+
128+
129+type ConstructADT :: K.Rel8able -> Type
130+type ConstructADT t = forall r. GGConstruct 'K.Sum (ADTRep t) r
131+
132+
133+constructADT :: forall t. ConstructableADT t => ConstructADT t -> ADT t Expr
134+constructADT f =
135+ ggconstruct @'K.Sum @(ADTRep t) @(ADT t Expr) ADT
136+ (f @(ADT t Expr))
137+
138+
139+type DeconstructADT :: K.Rel8able -> Type -> Type
140+type DeconstructADT t r = GGDeconstruct 'K.Sum (ADTRep t) (ADT t Expr) r
141+
142+
143+deconstructADT :: forall t r. (ConstructableADT t, Table Expr r)
144+ => DeconstructADT t r
145+deconstructADT =
146+ ggdeconstruct @'K.Sum @(ADTRep t) @(ADT t Expr) @r (\(ADT a) -> a)
147+
148+
149+type NameADT :: K.Rel8able -> Type
150+type NameADT t = GGName 'K.Sum (ADTRep t) (ADT t Name)
151+
152+
153+nameADT :: forall t. ConstructableADT t => NameADT t
154+nameADT = ggname @'K.Sum @(ADTRep t) @(ADT t Name) ADT
155+
156+
157+type AggregateADT :: K.Rel8able -> Type
158+type AggregateADT t = forall r. GGAggregate 'K.Sum (ADTRep t) r
159+
160+
161+aggregateADT :: forall t. ConstructableADT t
162+ => AggregateADT t -> ADT t Expr -> ADT t Aggregate
163+aggregateADT f =
164+ ggaggregate @'K.Sum @(ADTRep t) @(ADT t Expr) @(ADT t Aggregate) ADT (\(ADT a) -> a)
165+ (f @(ADT t Aggregate))
166+
167+
168+data ADTRep :: K.Rel8able -> K.Context -> Exp (Type -> Type)
169+type instance Eval (ADTRep t context) = GRep t context
170+
171+
172+type GColumnsADT :: K.Rel8able -> K.HTable
173+type GColumnsADT t = G.GColumnsADT TColumns (GRep t Expr)
src/Rel8/Table/Aggregate.hs+37−36
@@ -1,13 +1,13 @@
11{-# language FlexibleContexts #-}
2+{-# language NamedFieldPuns #-}
23{-# language ScopedTypeVariables #-}
34{-# language TypeApplications #-}
45{-# language TypeFamilies #-}
56{-# language ViewPatterns #-}
67
78module Rel8.Table.Aggregate
8− ( groupBy
9+ ( groupBy, hgroupBy
910 , listAgg, nonEmptyAgg
10− , listAggWithOrder, nonEmptyAggWithOrder
1111 )
1212where
1313
@@ -16,32 +16,49 @@ import Data.Functor.Identity ( Identity( Identity ) )
1616import Prelude
1717
1818-- rel8
19−import Rel8.Aggregate ( Aggregate, Col(..) )
20−import Rel8.Expr ( Expr, Col(..) )
19+import Rel8.Aggregate ( Aggregate, Aggregates )
20+import Rel8.Expr ( Expr )
2121import Rel8.Expr.Aggregate
2222 ( groupByExpr
23− , listAggExpr
24− , listAggExprWithOrder
25− , nonEmptyAggExpr
26− , nonEmptyAggExprWithOrder
23+ , slistAggExpr
24+ , snonEmptyAggExpr
2725 )
28−import Rel8.Order ( Order )
2926import Rel8.Schema.Dict ( Dict( Dict ) )
30−import Rel8.Schema.HTable ( htabulate, hfield )
27+import Rel8.Schema.HTable ( HTable, hfield, htabulate )
3128import Rel8.Schema.HTable.Vectorize ( hvectorize )
32−import Rel8.Table ( Table, toColumns, fromColumns )
29+import Rel8.Schema.Null ( Sql )
30+import Rel8.Schema.Spec ( Spec( Spec, info ) )
31+import Rel8.Table ( toColumns, fromColumns )
3332import Rel8.Table.Eq ( EqTable, eqTable )
3433import Rel8.Table.List ( ListTable )
3534import Rel8.Table.NonEmpty ( NonEmptyTable )
35+import Rel8.Type.Eq ( DBEq )
3636
3737
3838-- | Group equal tables together. This works by aggregating each column in the
3939-- given table with 'groupByExpr'.
40−groupBy :: forall exprs. EqTable exprs => exprs -> Aggregate exprs
41−groupBy (toColumns -> exprs) = fromColumns $ htabulate $ \field ->
42− case hfield (eqTable @exprs) field of
40+--
41+-- For example, if we have a table of items, we could group the items by the
42+-- order they belong to:
43+--
44+-- @
45+-- itemsByOrder :: Query (OrderId Expr, ListTable Expr (Item Expr))
46+-- itemsByOrder = aggregate $ do
47+-- item <- each itemSchema
48+-- let orderId = groupBy (itemOrderId item)
49+-- let orderItems = listAgg item
50+-- pure (orderId, orderItems)
51+-- @
52+groupBy :: forall exprs aggregates. (EqTable exprs, Aggregates aggregates exprs)
53+ => exprs -> aggregates
54+groupBy = fromColumns . hgroupBy (eqTable @exprs) . toColumns
55+
56+
57+hgroupBy :: HTable t => t (Dict (Sql DBEq)) -> t Expr -> t Aggregate
58+hgroupBy eqs exprs = htabulate $ \field ->
59+ case hfield eqs field of
4360 Dict -> case hfield exprs field of
44− DB expr -> Aggregation $ groupByExpr expr
61+ expr -> groupByExpr expr
4562
4663
4764-- | Aggregate rows into a single row containing an array of all aggregated
@@ -54,38 +71,22 @@ groupBy (toColumns -> exprs) = fromColumns $ htabulate $ \field ->
5471-- items:
5572--
5673-- @
57−-- ordersWithItems :: Query (Order Expr, ListTable (Item Expr))
74+-- ordersWithItems :: Query (Order Expr, ListTable Expr (Item Expr))
5875-- ordersWithItems = do
5976-- order <- each orderSchema
6077-- items <- aggregate $ listAgg <$> itemsFromOrder order
6178-- return (order, items)
6279-- @
63−listAgg :: Table Expr a => a -> Aggregate (ListTable a)
80+listAgg :: Aggregates aggregates exprs => exprs -> ListTable Aggregate aggregates
6481listAgg (toColumns -> exprs) = fromColumns $
6582 hvectorize
66− (\_ (Identity (DB a)) -> Aggregation $ listAggExpr a)
83+ (\Spec {info} (Identity a) -> slistAggExpr info a)
6784 (pure exprs)
6885
6986
7087-- | Like 'listAgg', but the result is guaranteed to be a non-empty list.
71−nonEmptyAgg :: Table Expr a => a -> Aggregate (NonEmptyTable a)
88+nonEmptyAgg :: Aggregates aggregates exprs => exprs -> NonEmptyTable Aggregate aggregates
7289nonEmptyAgg (toColumns -> exprs) = fromColumns $
7390 hvectorize
74− (\_ (Identity (DB a)) -> Aggregation $ nonEmptyAggExpr a)
75− (pure exprs)
76−
77−
78−listAggWithOrder :: Table Expr a
79− => Order o -> o -> a -> Aggregate (ListTable a)
80−listAggWithOrder order o (toColumns -> exprs) = fromColumns $
81− hvectorize
82− (\_ (Identity (DB x)) -> Aggregation $ listAggExprWithOrder order o x)
83− (pure exprs)
84−
85−
86−nonEmptyAggWithOrder :: Table Expr a
87− => Order o -> o -> a -> Aggregate (NonEmptyTable a)
88−nonEmptyAggWithOrder order o (toColumns -> exprs) = fromColumns $
89− hvectorize
90− (\_ (Identity (DB x)) -> Aggregation $ nonEmptyAggExprWithOrder order o x)
91+ (\Spec {info} (Identity a) -> snonEmptyAggExpr info a)
9192 (pure exprs)
src/Rel8/Table/Bool.hs+12−6
@@ -5,6 +5,7 @@
55module Rel8.Table.Bool
66 ( bool
77 , case_
8+ , nullable
89 )
910where
1011
@@ -12,8 +13,9 @@ where
1213import Prelude
1314
1415-- rel8
15−import Rel8.Expr ( Expr, Col(..) )
16+import Rel8.Expr ( Expr )
1617import Rel8.Expr.Bool ( boolExpr, caseExpr )
18+import Rel8.Expr.Null ( isNull, unsafeUnnullify )
1719import Rel8.Schema.HTable ( htabulate, hfield )
1820import Rel8.Table ( Table, fromColumns, toColumns )
1921
@@ -26,8 +28,7 @@ bool :: Table Expr a => a -> a -> Expr Bool -> a
2628bool (toColumns -> false) (toColumns -> true) condition =
2729 fromColumns $ htabulate $ \field ->
2830 case (hfield false field, hfield true field) of
29− (DB falseExpr, DB trueExpr) ->
30− DB (boolExpr falseExpr trueExpr condition)
31+ (falseExpr, trueExpr) -> boolExpr falseExpr trueExpr condition
3132{-# INLINABLE bool #-}
3233
3334
@@ -37,6 +38,11 @@ bool (toColumns -> false) (toColumns -> true) condition =
3738case_ :: Table Expr a => [(Expr Bool, a)] -> a -> a
3839case_ (map (fmap toColumns) -> branches) (toColumns -> fallback) =
3940 fromColumns $ htabulate $ \field -> case hfield fallback field of
40− DB fallbackExpr ->
41− case map (fmap (unDB . (`hfield` field))) branches of
42− branchExprs -> DB (caseExpr branchExprs fallbackExpr)
41+ fallbackExpr ->
42+ case map (fmap (`hfield` field)) branches of
43+ branchExprs -> caseExpr branchExprs fallbackExpr
44+
45+
46+-- | Like 'maybe', but to eliminate @null@.
47+nullable :: Table Expr b => b -> (Expr a -> b) -> Expr (Maybe a) -> b
48+nullable b f ma = bool (f (unsafeUnnullify ma)) b (isNull ma)
src/Rel8/Table/Cols.hsnew file+50
@@ -0,0 +1,50 @@
1+{-# language DataKinds #-}
2+{-# language FlexibleInstances #-}
3+{-# language MultiParamTypeClasses #-}
4+{-# language StandaloneKindSignatures #-}
5+{-# language TypeFamilies #-}
6+{-# language UndecidableInstances #-}
7+
8+module Rel8.Table.Cols
9+ ( Cols( Cols )
10+ , fromCols
11+ , toCols
12+ )
13+where
14+
15+-- base
16+import Data.Kind ( Type )
17+import Prelude
18+
19+-- rel8
20+import qualified Rel8.Schema.Kind as K
21+import Rel8.Schema.HTable ( HTable )
22+import Rel8.Schema.Result ( Result )
23+import Rel8.Table ( Table(..) )
24+
25+
26+type Cols :: K.Context -> K.HTable -> Type
27+newtype Cols context columns = Cols (columns context)
28+
29+
30+instance (HTable columns, context ~ context') =>
31+ Table context' (Cols context columns)
32+ where
33+ type Columns (Cols context columns) = columns
34+ type Context (Cols context columns) = context
35+ type FromExprs (Cols context columns) = Cols Result columns
36+ type Transpose to (Cols context columns) = Cols to columns
37+
38+ toColumns (Cols a) = a
39+ fromColumns = Cols
40+
41+ toResult (Cols a) = a
42+ fromResult = Cols
43+
44+
45+fromCols :: Table context a => Cols context (Columns a) -> a
46+fromCols (Cols a) = fromColumns a
47+
48+
49+toCols :: Table context a => a -> Cols context (Columns a)
50+toCols = Cols . toColumns
src/Rel8/Table/Either.hs+154−126
@@ -3,6 +3,7 @@
33{-# language DerivingStrategies #-}
44{-# language FlexibleContexts #-}
55{-# language FlexibleInstances #-}
6+{-# language LambdaCase #-}
67{-# language MultiParamTypeClasses #-}
78{-# language NamedFieldPuns #-}
89{-# language ScopedTypeVariables #-}
@@ -11,205 +12,232 @@
1112{-# language TypeFamilies #-}
1213{-# language UndecidableInstances #-}
1314
15+{-# options_ghc -fno-warn-orphans #-}
16+
1417module Rel8.Table.Either
1518 ( EitherTable(..)
1619 , eitherTable, leftTable, rightTable
1720 , isLeftTable, isRightTable
18− , aggregateEitherTable, nameEitherTable
21+ , aggregateEitherTable
22+ , nameEitherTable
1923 )
2024where
2125
2226-- base
2327import Data.Bifunctor ( Bifunctor, bimap )
24−import Data.Functor.Identity ( runIdentity )
28+import Data.Functor.Identity ( Identity( Identity ) )
2529import Data.Kind ( Type )
2630import Prelude hiding ( undefined )
2731
32+-- comonad
33+import Control.Comonad ( extract )
34+
2835-- rel8
29−import Rel8.Aggregate ( Aggregate, unsafeMakeAggregate )
36+import Rel8.Aggregate ( Aggregate )
3037import Rel8.Expr ( Expr )
31−import Rel8.Expr.Opaleye ( fromPrimExpr, toPrimExpr )
38+import Rel8.Expr.Aggregate ( groupByExpr )
3239import Rel8.Expr.Serialize ( litExpr )
33−import Rel8.Schema.Context.Label
34− ( Labelable
35− , HLabelable, hlabeler, hunlabeler
36− )
37−import Rel8.Schema.Context.Nullify
38− ( Nullifiable, ConstrainTag
39− , HNullifiable, HConstrainTag
40− , hencodeTag, hdecodeTag
41− , hnullifier, hunnullifier
42− )
43−import Rel8.Schema.HTable ( HTable )
40+import Rel8.Kind.Context ( Reifiable )
41+import Rel8.Schema.Context.Nullify ( Nullifiable )
42+import Rel8.Schema.Dict ( Dict( Dict ) )
4443import Rel8.Schema.HTable.Either ( HEitherTable(..) )
4544import Rel8.Schema.HTable.Identity ( HIdentity(..) )
4645import Rel8.Schema.HTable.Label ( hlabel, hunlabel )
47−import Rel8.Schema.HTable.Nullify ( hnullify, hunnullify )
46+import qualified Rel8.Schema.Kind as K
4847import Rel8.Schema.Name ( Name )
49−import Rel8.Table ( Table, Columns, Context, fromColumns, toColumns )
48+import Rel8.Table
49+ ( Table, Columns, Context, fromColumns, toColumns
50+ , FromExprs, fromResult, toResult
51+ , Transpose
52+ )
5053import Rel8.Table.Bool ( bool )
5154import Rel8.Table.Eq ( EqTable, eqTable )
55+import Rel8.Table.Nullify ( Nullify, aggregateNullify, guard )
5256import Rel8.Table.Ord ( OrdTable, ordTable )
53−import Rel8.Table.Recontextualize ( Recontextualize )
54−import Rel8.Table.Tag ( Tag(..), fromExpr, fromName )
57+import Rel8.Table.Projection ( Biprojectable, Projectable, biproject, project )
58+import Rel8.Table.Serialize ( ToExprs )
5559import Rel8.Table.Undefined ( undefined )
5660import Rel8.Type.Tag ( EitherTag( IsLeft, IsRight ), isLeft, isRight )
5761
5862-- semigroupoids
59−import Data.Functor.Apply ( Apply, (<.>), liftF3 )
63+import Data.Functor.Apply ( Apply, (<.>) )
6064import Data.Functor.Bind ( Bind, (>>-) )
6165
6266
63−type EitherTable :: Type -> Type -> Type
64−data EitherTable a b = EitherTable
65− { tag :: Tag "isRight" EitherTag
66− , left :: a
67− , right :: b
67+-- | An @EitherTable a b@ is a Rel8 table that contains either the table @a@ or
68+-- the table @b@. You can construct an @EitherTable@ using 'leftTable' and
69+-- 'rightTable', and eliminate/pattern match using 'eitherTable'.
70+--
71+-- An @EitherTable@ is operationally the same as Haskell's 'Either' type, but
72+-- adapted to work with Rel8.
73+type EitherTable :: K.Context -> Type -> Type -> Type
74+data EitherTable context a b = EitherTable
75+ { tag :: context EitherTag
76+ , left :: Nullify context a
77+ , right :: Nullify context b
6878 }
6979 deriving stock Functor
7080
7181
72−instance Bifunctor EitherTable where
73− bimap f g (EitherTable tag a b) = EitherTable tag (f a) (g b)
82+instance Biprojectable (EitherTable context) where
83+ biproject f g (EitherTable tag a b) =
84+ EitherTable tag (project f a) (project g b)
85+
7486
87+instance Nullifiable context => Bifunctor (EitherTable context) where
88+ bimap f g (EitherTable tag a b) = EitherTable tag (fmap f a) (fmap g b)
7589
76−instance Table Expr a => Apply (EitherTable a) where
90+
91+instance Projectable (EitherTable context a) where
92+ project f (EitherTable tag a b) = EitherTable tag a (project f b)
93+
94+
95+instance (context ~ Expr, Table Expr a) => Apply (EitherTable context a) where
7796 EitherTable tag l1 f <.> EitherTable tag' l2 a =
78− EitherTable (tag <> tag') (bool l1 l2 (isLeft (expr tag))) (f a)
97+ EitherTable (tag <> tag') (bool l1 l2 (isLeft tag)) (f <.> a)
7998
8099
81−instance Table Expr a => Applicative (EitherTable a) where
100+instance (context ~ Expr, Table Expr a) => Applicative (EitherTable context a) where
82101 pure = rightTable
83102 (<*>) = (<.>)
84103
85104
86−instance Table Expr a => Bind (EitherTable a) where
87− EitherTable tag l1 a >>- f = case f a of
105+instance (context ~ Expr, Table Expr a) => Bind (EitherTable context a) where
106+ EitherTable tag l1 a >>- f = case f (extract a) of
88107 EitherTable tag' l2 b ->
89− EitherTable (tag <> tag') (bool l1 l2 (isRight (expr tag))) b
108+ EitherTable (tag <> tag') (bool l1 l2 (isRight tag)) b
90109
91110
92−instance Table Expr a => Monad (EitherTable a) where
111+instance (context ~ Expr, Table Expr a) => Monad (EitherTable context a) where
93112 (>>=) = (>>-)
94113
95114
96−instance (Table Expr a, Table Expr b) => Semigroup (EitherTable a b) where
115+instance (context ~ Expr, Table Expr a, Table Expr b) =>
116+ Semigroup (EitherTable context a b)
117+ where
97118 a <> b = bool a b (isRightTable a)
98119
99120
100121instance
101122 ( Table context a, Table context b
102− , Labelable context, Nullifiable context, ConstrainTag context EitherTag
103− ) =>
104− Table context (EitherTable a b)
123+ , Reifiable context, context ~ context'
124+ )
125+ => Table context' (EitherTable context a b)
105126 where
106− type Columns (EitherTable a b) = HEitherTable (Columns a) (Columns b)
107− type Context (EitherTable a b) = Context a
108−
109− toColumns = toColumns2 toColumns toColumns
110− fromColumns = fromColumns2 fromColumns fromColumns
111−
112−
113−instance
114− ( Nullifiable from, Labelable from, ConstrainTag from EitherTag
115− , Nullifiable to, Labelable to, ConstrainTag to EitherTag
116− , Recontextualize from to a1 b1
117− , Recontextualize from to a2 b2
118− ) =>
119− Recontextualize from to (EitherTable a1 a2) (EitherTable b1 b2)
127+ type Columns (EitherTable context a b) = HEitherTable (Columns a) (Columns b)
128+ type Context (EitherTable context a b) = Context a
129+ type FromExprs (EitherTable context a b) = Either (FromExprs a) (FromExprs b)
130+ type Transpose to (EitherTable context a b) =
131+ EitherTable to (Transpose to a) (Transpose to b)
132+
133+ toColumns EitherTable {tag, left, right} = HEitherTable
134+ { htag = hlabel $ HIdentity tag
135+ , hleft = hlabel $ guard tag (== IsLeft) isLeft $ toColumns left
136+ , hright = hlabel $ guard tag (== IsRight) isRight $ toColumns right
137+ }
138+
139+ fromColumns HEitherTable {htag, hleft, hright} = EitherTable
140+ { tag = unHIdentity $ hunlabel htag
141+ , left = fromColumns $ hunlabel hleft
142+ , right = fromColumns $ hunlabel hright
143+ }
144+
145+ toResult = \case
146+ Left table -> HEitherTable
147+ { htag = hlabel (HIdentity (Identity IsLeft))
148+ , hleft = hlabel (toResult @_ @(Nullify context a) (Just table))
149+ , hright = hlabel (toResult @_ @(Nullify context b) Nothing)
150+ }
151+ Right table -> HEitherTable
152+ { htag = hlabel (HIdentity (Identity IsRight))
153+ , hleft = hlabel (toResult @_ @(Nullify context a) Nothing)
154+ , hright = hlabel (toResult @_ @(Nullify context b) (Just table))
155+ }
156+
157+ fromResult HEitherTable {htag, hleft, hright} = case hunlabel htag of
158+ HIdentity (Identity tag) -> case tag of
159+ IsLeft -> maybe err Left $ fromResult @_ @(Nullify context a) (hunlabel hleft)
160+ IsRight -> maybe err Right $ fromResult @_ @(Nullify context b) (hunlabel hright)
161+ where
162+ err = error "Either.fromColumns: mismatch between tag and data"
163+
164+
165+instance (EqTable a, EqTable b, context ~ Expr) =>
166+ EqTable (EitherTable context a b)
167+ where
168+ eqTable = HEitherTable
169+ { htag = hlabel (HIdentity Dict)
170+ , hleft = hlabel (eqTable @(Nullify context a))
171+ , hright = hlabel (eqTable @(Nullify context b))
172+ }
120173
121174
122−instance (EqTable a, EqTable b) => EqTable (EitherTable a b) where
123− eqTable = toColumns2 id id (rightTableWith (eqTable @a) (eqTable @b))
175+instance (OrdTable a, OrdTable b, context ~ Expr) =>
176+ OrdTable (EitherTable context a b)
177+ where
178+ ordTable = HEitherTable
179+ { htag = hlabel (HIdentity Dict)
180+ , hleft = hlabel (ordTable @(Nullify context a))
181+ , hright = hlabel (ordTable @(Nullify context b))
182+ }
124183
125184
126−instance (OrdTable a, OrdTable b) => OrdTable (EitherTable a b) where
127− ordTable = toColumns2 id id (rightTableWith (ordTable @a) (ordTable @b))
185+instance (ToExprs exprs1 a, ToExprs exprs2 b, x ~ EitherTable Expr exprs1 exprs2) =>
186+ ToExprs x (Either a b)
128187
129188
130−isLeftTable :: EitherTable a b -> Expr Bool
131−isLeftTable = isLeft . expr . tag
189+-- | Test if an 'EitherTable' is a 'leftTable'.
190+isLeftTable :: EitherTable Expr a b -> Expr Bool
191+isLeftTable EitherTable {tag} = isLeft tag
132192
133193
134−isRightTable :: EitherTable a b -> Expr Bool
135−isRightTable = isRight . expr . tag
194+-- | Test if an 'EitherTable' is a 'rightTable'.
195+isRightTable :: EitherTable Expr a b -> Expr Bool
196+isRightTable EitherTable {tag} = isRight tag
136197
137198
199+-- | Pattern match/eliminate an 'EitherTable', by providing mappings from a
200+-- 'leftTable' and 'rightTable'.
138201eitherTable :: Table Expr c
139− => (a -> c) -> (b -> c) -> EitherTable a b -> c
202+ => (a -> c) -> (b -> c) -> EitherTable Expr a b -> c
140203eitherTable f g EitherTable {tag, left, right} =
141− bool (f left) (g right) (isRight (expr tag))
204+ bool (f (extract left)) (g (extract right)) (isRight tag)
142205
143206
144−leftTable :: Table Expr b => a -> EitherTable a b
145−leftTable a = EitherTable (fromExpr (litExpr IsLeft)) a undefined
207+-- | Construct a left 'EitherTable'. Like 'Left'.
208+leftTable :: Table Expr b => a -> EitherTable Expr a b
209+leftTable a = EitherTable (litExpr IsLeft) (pure a) undefined
146210
147211
148−rightTable :: Table Expr a => b -> EitherTable a b
149−rightTable = rightTableWith undefined
150−
151−
152−rightTableWith :: a -> b -> EitherTable a b
153−rightTableWith = EitherTable (fromExpr (litExpr IsRight))
212+-- | Construct a right 'EitherTable'. Like 'Right'.
213+rightTable :: Table Expr a => b -> EitherTable Expr a b
214+rightTable = EitherTable (litExpr IsRight) undefined . pure
154215
155216
217+-- | Lift a pair of aggregating functions to operate on an 'EitherTable'.
218+-- @leftTable@s and @rightTable@s are grouped separately.
156219aggregateEitherTable :: ()
157− => (a -> Aggregate c)
158− -> (b -> Aggregate d)
159− -> EitherTable a b
160− -> Aggregate (EitherTable c d)
161−aggregateEitherTable f g EitherTable {tag, left, right} =
162− liftF3 EitherTable (tag <$ aggregate) (f left) (g right)
163− where
164− Tag {aggregator, expr} = tag
165− aggregate = unsafeMakeAggregate toPrimExpr fromPrimExpr aggregator expr
166−
167−
168−nameEitherTable :: Name EitherTag -> a -> b -> EitherTable a b
169−nameEitherTable = EitherTable . fromName
170−
171−
172−toColumns2 ::
173− ( HTable t
174− , HTable u
175− , HConstrainTag context EitherTag
176− , HLabelable context
177− , HNullifiable context
178− )
179− => (a -> t context)
180− -> (b -> u context)
181− -> EitherTable a b
182− -> HEitherTable t u context
183−toColumns2 f g EitherTable {tag, left, right} = HEitherTable
184− { htag
185− , hleft = hlabel hlabeler $ hnullify (hnullifier tag isLeft) $ f left
186− , hright = hlabel hlabeler $ hnullify (hnullifier tag isRight) $ g right
220+ => (exprs -> aggregates)
221+ -> (exprs' -> aggregates')
222+ -> EitherTable Expr exprs exprs'
223+ -> EitherTable Aggregate aggregates aggregates'
224+aggregateEitherTable f g (EitherTable tag a b) = EitherTable
225+ { tag = groupByExpr tag
226+ , left = aggregateNullify f a
227+ , right = aggregateNullify g b
187228 }
188− where
189− htag = HIdentity (hencodeTag tag)
190229
191230
192−fromColumns2 ::
193− ( HTable t
194− , HTable u
195− , HConstrainTag context EitherTag
196− , HLabelable context
197− , HNullifiable context
198− )
199− => (t context -> a)
200− -> (u context -> b)
201− -> HEitherTable t u context
202− -> EitherTable a b
203−fromColumns2 f g HEitherTable {htag, hleft, hright} = EitherTable
204− { tag
205− , left = f $ runIdentity $
206− hunnullify (\a -> pure . hunnullifier a) $
207− hunlabel hunlabeler
208− hleft
209− , right = g $ runIdentity $
210− hunnullify (\a -> pure . hunnullifier a) $
211− hunlabel hunlabeler
212− hright
213− }
214− where
215− tag = hdecodeTag $ unHIdentity htag
231+-- | Construct a 'EitherTable' in the 'Name' context. This can be useful if you
232+-- have a 'EitherTable' that you are storing in a table and need to construct a
233+-- 'TableSchema'.
234+nameEitherTable
235+ :: Name EitherTag
236+ -- ^ The name of the column to track whether a row is a 'leftTable' or
237+ -- 'rightTable'.
238+ -> a
239+ -- ^ Names of the columns in the @a@ table.
240+ -> b
241+ -- ^ Names of the columns in the @b@ table.
242+ -> EitherTable Name a b
243+nameEitherTable tag left right = EitherTable tag (pure left) (pure right)
src/Rel8/Table/Eq.hs+12−39
@@ -11,7 +11,6 @@
1111{-# language TypeFamilies #-}
1212{-# language TypeOperators #-}
1313{-# language UndecidableInstances #-}
14−{-# language UndecidableSuperClasses #-}
1514{-# language ViewPatterns #-}
1615
1716module Rel8.Table.Eq
@@ -24,26 +23,20 @@ import Data.Foldable ( foldl' )
2423import Data.Functor.Const ( Const( Const ), getConst )
2524import Data.Kind ( Constraint, Type )
2625import Data.List.NonEmpty ( NonEmpty( (:|) ) )
27−import Data.Proxy ( Proxy )
2826import GHC.Generics ( Rep )
2927import Prelude
3028
3129-- rel8
32−import Rel8.Expr ( Expr, Col(..) )
30+import Rel8.Expr ( Expr )
3331import Rel8.Expr.Bool ( (||.), (&&.) )
3432import Rel8.Expr.Eq ( (==.), (/=.) )
3533import Rel8.FCF ( Eval, Exp )
3634import Rel8.Generic.Record ( Record )
37−import Rel8.Generic.Table ( GTable, GColumns, gtable )
35+import Rel8.Generic.Table.Record ( GTable, GColumns, gtable )
3836import Rel8.Schema.Dict ( Dict( Dict ) )
39−import Rel8.Schema.HTable
40− ( HTable, HConstrainTable
41− , htabulateA, hfield, hdicts
42− )
43−import Rel8.Schema.HTable.Type ( HType(..) )
44−import Rel8.Schema.Kind ( Context )
37+import Rel8.Schema.HTable ( htabulateA, hfield )
38+import Rel8.Schema.HTable.Identity ( HIdentity( HIdentity ) )
4539import Rel8.Schema.Null ( Sql )
46−import Rel8.Schema.Spec.ConstrainDBType ( ConstrainDBType )
4740import Rel8.Table ( Table, Columns, toColumns, TColumns )
4841import Rel8.Type.Eq ( DBEq )
4942
@@ -53,44 +46,24 @@ import Rel8.Type.Eq ( DBEq )
5346-- means "all columns in a 'Table' have an instance of 'DBEq'".
5447type EqTable :: Type -> Constraint
5548class Table Expr a => EqTable a where
56− eqTable :: Columns a (Dict (ConstrainDBType DBEq))
49+ eqTable :: Columns a (Dict (Sql DBEq))
5750
5851 default eqTable ::
59− ( GTable TEqTable TColumns (Dict (ConstrainDBType DBEq)) (Rep (Record a))
52+ ( GTable TEqTable TColumns (Rep (Record a))
6053 , Columns a ~ GColumns TColumns (Rep (Record a))
6154 )
62− => Columns a (Dict (ConstrainDBType DBEq))
63− eqTable = gtable @TEqTable @TColumns @_ @(Rep (Record a)) table
55+ => Columns a (Dict (Sql DBEq))
56+ eqTable = gtable @TEqTable @TColumns @(Rep (Record a)) table
6457 where
65− table (_ :: Proxy x) = eqTable @x
58+ table (_ :: proxy x) = eqTable @x
6659
6760
6861data TEqTable :: Type -> Exp Constraint
6962type instance Eval (TEqTable a) = EqTable a
7063
7164
72−instance
73− ( Table Expr (t (Expr :: Context))
74− , f ~ Expr
75− , HConstrainTable (Columns (t Expr)) (ConstrainDBType DBEq)
76− )
77− => EqTable (t f)
78− where
79− eqTable = hdicts @(Columns (t f)) @(ConstrainDBType DBEq)
80−
81−
82−instance
83− ( HTable t
84− , f ~ Col Expr
85− , HConstrainTable t (ConstrainDBType DBEq)
86− )
87− => EqTable (t f)
88− where
89− eqTable = hdicts @(Columns (t f)) @(ConstrainDBType DBEq)
90−
91−
9265instance Sql DBEq a => EqTable (Expr a) where
93− eqTable = HType Dict
66+ eqTable = HIdentity Dict
9467
9568
9669instance (EqTable a, EqTable b) => EqTable (a, b)
@@ -124,7 +97,7 @@ instance
12497(toColumns -> as) ==: (toColumns -> bs) =
12598 foldl1' (&&.) $ getConst $ htabulateA $ \field ->
12699 case (hfield as field, hfield bs field) of
127− (DB a, DB b) -> case hfield (eqTable @a) field of
100+ (a, b) -> case hfield (eqTable @a) field of
128101 Dict -> Const (pure (a ==. b))
129102infix 4 ==:
130103
@@ -136,7 +109,7 @@ infix 4 ==:
136109(toColumns -> as) /=: (toColumns -> bs) =
137110 foldl1' (||.) $ getConst $ htabulateA $ \field ->
138111 case (hfield as field, hfield bs field) of
139− (DB a, DB b) -> case hfield (eqTable @a) field of
112+ (a, b) -> case hfield (eqTable @a) field of
140113 Dict -> Const (pure (a /=. b))
141114infix 4 /=:
142115
src/Rel8/Table/HKD.hsnew file+228
@@ -0,0 +1,228 @@
1+{-# language AllowAmbiguousTypes #-}
2+{-# language DataKinds #-}
3+{-# language FlexibleContexts #-}
4+{-# language FlexibleInstances #-}
5+{-# language MultiParamTypeClasses #-}
6+{-# language RankNTypes #-}
7+{-# language ScopedTypeVariables #-}
8+{-# language StandaloneKindSignatures #-}
9+{-# language TypeApplications #-}
10+{-# language TypeFamilies #-}
11+{-# language UndecidableInstances #-}
12+{-# language UndecidableSuperClasses #-}
13+
14+module Rel8.Table.HKD
15+ ( HKD( HKD )
16+ , HKDable
17+ , BuildableHKD
18+ , BuildHKD, buildHKD
19+ , ConstructableHKD
20+ , ConstructHKD, constructHKD
21+ , DeconstructHKD, deconstructHKD
22+ , NameHKD, nameHKD
23+ , AggregateHKD, aggregateHKD
24+ , HKDRep
25+ )
26+where
27+
28+-- base
29+import Data.Kind ( Constraint, Type )
30+import GHC.Generics ( Generic, Rep, from, to )
31+import GHC.TypeLits ( Symbol )
32+import Prelude
33+
34+-- rel8
35+import Rel8.Aggregate ( Aggregate )
36+import Rel8.Column ( TColumn )
37+import Rel8.Expr ( Expr )
38+import Rel8.FCF ( Eval, Exp )
39+import Rel8.Kind.Algebra ( KnownAlgebra )
40+import Rel8.Generic.Construction
41+ ( GGBuildable
42+ , GGBuild, ggbuild
43+ , GGConstructable
44+ , GGConstruct, ggconstruct
45+ , GGDeconstruct, ggdeconstruct
46+ , GGName, ggname
47+ , GGAggregate, ggaggregate
48+ )
49+import Rel8.Generic.Map ( GMap )
50+import Rel8.Generic.Record
51+ ( GRecord, GRecordable, grecord, gunrecord
52+ , Record( Record ), unrecord
53+ )
54+import Rel8.Generic.Rel8able
55+ ( Rel8able
56+ , GColumns, gfromColumns, gtoColumns
57+ , GFromExprs, gfromResult, gtoResult
58+ )
59+import Rel8.Generic.Table
60+ ( GGSerialize, GGColumns, GAlgebra, ggfromResult, ggtoResult
61+ )
62+import Rel8.Generic.Table.Record ( GTable, GContext )
63+import qualified Rel8.Generic.Table.Record as G
64+import qualified Rel8.Schema.Kind as K
65+import Rel8.Schema.HTable ( HTable )
66+import Rel8.Schema.Name ( Name )
67+import Rel8.Schema.Result ( Result )
68+import Rel8.Table
69+ ( Table, fromColumns, toColumns, fromResult, toResult
70+ , TTable, TColumns, TContext
71+ , TSerialize
72+ )
73+
74+
75+type GColumnsHKD :: Type -> K.HTable
76+type GColumnsHKD a =
77+ Eval (GGColumns (GAlgebra (Rep a)) TColumns (GRecord (GMap (TColumn Expr) (Rep a))))
78+
79+
80+type HKD :: Type -> K.Rel8able
81+newtype HKD a f = HKD (GColumnsHKD a f)
82+
83+
84+instance HKDable a => Rel8able (HKD a) where
85+ type GColumns (HKD a) = GColumnsHKD a
86+ type GFromExprs (HKD a) = a
87+
88+ gfromColumns _ = HKD
89+ gtoColumns _ (HKD a) = a
90+
91+ gfromResult =
92+ unrecord .
93+ to .
94+ ggfromResult
95+ @(GAlgebra (Rep a))
96+ @TSerialize
97+ @TColumns
98+ @(Eval (HKDRep a Expr))
99+ @(Eval (HKDRep a Result))
100+ (\(_ :: proxy x) -> fromResult @_ @x)
101+
102+ gtoResult =
103+ ggtoResult
104+ @(GAlgebra (Rep a))
105+ @TSerialize
106+ @TColumns
107+ @(Eval (HKDRep a Expr))
108+ @(Eval (HKDRep a Result))
109+ (\(_ :: proxy x) -> toResult @_ @x) .
110+ from .
111+ Record
112+
113+
114+instance
115+ ( GTable (TTable f) TColumns (GRecord (GMap (TColumn f) (Rep a)))
116+ , G.GColumns TColumns (GRecord (GMap (TColumn f) (Rep a))) ~ GColumnsHKD a
117+ , GContext TContext (GRecord (GMap (TColumn f) (Rep a))) ~ f
118+ , GRecordable (GMap (TColumn f) (Rep a))
119+ )
120+ => Generic (HKD a f)
121+ where
122+ type Rep (HKD a f) = GMap (TColumn f) (Rep a)
123+
124+ from =
125+ gunrecord @(GMap (TColumn f) (Rep a)) .
126+ G.gfromColumns
127+ @(TTable f)
128+ @TColumns
129+ fromColumns .
130+ (\(HKD a) -> a)
131+
132+ to =
133+ HKD .
134+ G.gtoColumns
135+ @(TTable f)
136+ @TColumns
137+ toColumns .
138+ grecord @(GMap (TColumn f) (Rep a))
139+
140+
141+type HKDable :: Type -> Constraint
142+class
143+ ( Generic (Record a)
144+ , HTable (GColumns (HKD a))
145+ , KnownAlgebra (GAlgebra (Rep a))
146+ , Eval (GGSerialize (GAlgebra (Rep a)) TSerialize TColumns (Eval (HKDRep a Expr)) (Eval (HKDRep a Result)))
147+ , GRecord (GMap (TColumn Result) (Rep a)) ~ Rep (Record a)
148+ )
149+ => HKDable a
150+instance
151+ ( Generic (Record a)
152+ , HTable (GColumns (HKD a))
153+ , KnownAlgebra (GAlgebra (Rep a))
154+ , Eval (GGSerialize (GAlgebra (Rep a)) TSerialize TColumns (Eval (HKDRep a Expr)) (Eval (HKDRep a Result)))
155+ , GRecord (GMap (TColumn Result) (Rep a)) ~ Rep (Record a)
156+ )
157+ => HKDable a
158+
159+
160+type Top_ :: Constraint
161+class Top_
162+instance Top_
163+
164+
165+data Top :: Type -> Exp Constraint
166+type instance Eval (Top _) = Top_
167+
168+
169+type BuildableHKD :: Type -> Symbol -> Constraint
170+class GGBuildable (GAlgebra (Rep a)) name (HKDRep a) => BuildableHKD a name
171+instance GGBuildable (GAlgebra (Rep a)) name (HKDRep a) => BuildableHKD a name
172+
173+
174+type BuildHKD :: Type -> Symbol -> Type
175+type BuildHKD a name = GGBuild (GAlgebra (Rep a)) name (HKDRep a) (HKD a Expr)
176+
177+
178+buildHKD :: forall a name. BuildableHKD a name => BuildHKD a name
179+buildHKD =
180+ ggbuild @(GAlgebra (Rep a)) @name @(HKDRep a) @(HKD a Expr) HKD
181+
182+
183+type ConstructableHKD :: Type -> Constraint
184+class GGConstructable (GAlgebra (Rep a)) (HKDRep a) => ConstructableHKD a
185+instance GGConstructable (GAlgebra (Rep a)) (HKDRep a) => ConstructableHKD a
186+
187+
188+type ConstructHKD :: Type -> Type
189+type ConstructHKD a = forall r. GGConstruct (GAlgebra (Rep a)) (HKDRep a) r
190+
191+
192+constructHKD :: forall a. ConstructableHKD a => ConstructHKD a -> HKD a Expr
193+constructHKD f =
194+ ggconstruct @(GAlgebra (Rep a)) @(HKDRep a) @(HKD a Expr) HKD
195+ (f @(HKD a Expr))
196+
197+
198+type DeconstructHKD :: Type -> Type -> Type
199+type DeconstructHKD a r = GGDeconstruct (GAlgebra (Rep a)) (HKDRep a) (HKD a Expr) r
200+
201+
202+deconstructHKD :: forall a r. (ConstructableHKD a, Table Expr r)
203+ => DeconstructHKD a r
204+deconstructHKD = ggdeconstruct @(GAlgebra (Rep a)) @(HKDRep a) @(HKD a Expr) @r (\(HKD a) -> a)
205+
206+
207+type NameHKD :: Type -> Type
208+type NameHKD a = GGName (GAlgebra (Rep a)) (HKDRep a) (HKD a Name)
209+
210+
211+nameHKD :: forall a. ConstructableHKD a => NameHKD a
212+nameHKD = ggname @(GAlgebra (Rep a)) @(HKDRep a) @(HKD a Name) HKD
213+
214+
215+type AggregateHKD :: Type -> Type
216+type AggregateHKD a = forall r. GGAggregate (GAlgebra (Rep a)) (HKDRep a) r
217+
218+
219+aggregateHKD :: forall a. ConstructableHKD a
220+ => AggregateHKD a -> HKD a Expr -> HKD a Aggregate
221+aggregateHKD f =
222+ ggaggregate @(GAlgebra (Rep a)) @(HKDRep a) @(HKD a Expr) @(HKD a Aggregate) HKD (\(HKD a) -> a)
223+ (f @(HKD a Aggregate))
224+
225+
226+data HKDRep :: Type -> K.Context -> Exp (Type -> Type)
227+type instance Eval (HKDRep a context) =
228+ GRecord (GMap (TColumn context) (Rep a))
src/Rel8/Table/Insert.hsdeleted−51
@@ -1,51 +0,0 @@
1−{-# language FlexibleContexts #-}
2−{-# language NamedFieldPuns #-}
3−{-# language TypeFamilies #-}
4−{-# language ViewPatterns #-}
5−
6−module Rel8.Table.Insert
7− ( toInsert
8− , toInsertDefaults
9− )
10−where
11−
12−-- base
13−import Prelude
14−
15−-- rel8
16−import Rel8.Expr ( Col(..) )
17−import Rel8.Kind.Necessity ( SNecessity( SOptional, SRequired ) )
18−import Rel8.Schema.HTable ( hfield, htabulate, hspecs )
19−import Rel8.Schema.Insert ( Inserts, Col(..) )
20−import Rel8.Schema.Spec ( SSpec(..) )
21−import Rel8.Table ( fromColumns, toColumns )
22−
23−
24−-- | @toInsert@ converts a 'Table' of 'Expr's into a 'Table' that can be used
25−-- with 'Rel8.insert'. This will override any columns that have default values
26−-- to use exactly what is given. If you want to use default values, you can
27−-- either override the result of @toInsert@, or use 'toInsertDefaults'.
28−toInsert :: Inserts exprs inserts => exprs -> inserts
29−toInsert (toColumns -> exprs) = fromColumns $ htabulate $ \field ->
30− case hfield hspecs field of
31− SSpec {necessity} -> case hfield exprs field of
32− DB expr -> case necessity of
33− SRequired -> RequiredInsert expr
34− SOptional -> OptionalInsert (Just expr)
35−
36−
37−-- | @toInsertDefaults@ converts a 'Table' of 'Expr's into a 'Table' that can
38−-- be used with 'Rel8.insert'. Any columns that have a default value will
39−-- override whatever is in the input expression.
40−--
41−-- One example where this is useful is for any table that has a special @id@
42−-- column, which has a default value to draw a new value from a sequence. If we
43−-- use 'toInsertDefaults', we can provide a dummy value that will be replaced
44−-- with a call to @DEFAULT@.
45−toInsertDefaults :: Inserts exprs inserts => exprs -> inserts
46−toInsertDefaults (toColumns -> exprs) = fromColumns $ htabulate $ \field ->
47− case hfield hspecs field of
48− SSpec {necessity} -> case hfield exprs field of
49− DB expr -> case necessity of
50− SRequired -> RequiredInsert expr
51− SOptional -> OptionalInsert Nothing
src/Rel8/Table/List.hs+83−35
@@ -1,3 +1,4 @@
1+{-# language DataKinds #-}
12{-# language FlexibleContexts #-}
23{-# language FlexibleInstances #-}
34{-# language MultiParamTypeClasses #-}
@@ -10,7 +11,9 @@
1011
1112module Rel8.Table.List
1213 ( ListTable(..)
14+ , ($*)
1315 , listTable
16+ , nameListTable
1417 )
1518where
1619
@@ -20,82 +23,127 @@ import Data.Kind ( Type )
2023import Prelude
2124
2225-- rel8
23−import Rel8.Expr ( Expr, Col(..) )
26+import Rel8.Expr ( Expr )
2427import Rel8.Expr.Array ( sappend, sempty, slistOf )
2528import Rel8.Schema.Dict ( Dict( Dict ) )
2629import Rel8.Schema.HTable.List ( HListTable )
27−import Rel8.Schema.HTable.Vectorize ( happend, hempty, hvectorize )
30+import Rel8.Schema.HTable.Vectorize
31+ ( hvectorize, hunvectorize
32+ , happend, hempty
33+ , hproject, hcolumn
34+ )
35+import qualified Rel8.Schema.Kind as K
36+import Rel8.Schema.Name ( Name( Name ) )
2837import Rel8.Schema.Null ( Nullity( Null, NotNull ) )
29−import Rel8.Schema.Spec ( SSpec(..) )
30−import Rel8.Schema.Spec.ConstrainDBType ( dbTypeDict, dbTypeNullity )
31−import Rel8.Table ( Table, Context, Columns, fromColumns, toColumns )
38+import Rel8.Schema.Result ( vectorizer, unvectorizer )
39+import Rel8.Schema.Spec ( Spec(..) )
40+import Rel8.Table
41+ ( Table, Context, Columns, fromColumns, toColumns
42+ , FromExprs, fromResult, toResult
43+ , Transpose
44+ )
3245import Rel8.Table.Alternative
3346 ( AltTable, (<|>:)
3447 , AlternativeTable, emptyTable
3548 )
3649import Rel8.Table.Eq ( EqTable, eqTable )
3750import Rel8.Table.Ord ( OrdTable, ordTable )
38−import Rel8.Table.Recontextualize ( Recontextualize )
51+import Rel8.Table.Projection
52+ ( Projectable, Projecting, Projection, project, apply
53+ )
54+import Rel8.Table.Serialize ( ToExprs )
3955
4056
4157-- | A @ListTable@ value contains zero or more instances of @a@. You construct
4258-- @ListTable@s with 'Rel8.many' or 'Rel8.listAgg'.
43−type ListTable :: Type -> Type
44−newtype ListTable a = ListTable (HListTable (Columns a) (Col (Context a)))
59+type ListTable :: K.Context -> Type -> Type
60+newtype ListTable context a =
61+ ListTable (HListTable (Columns a) (Context a))
4562
4663
47−instance Table context a => Table context (ListTable a) where
48− type Columns (ListTable a) = HListTable (Columns a)
49− type Context (ListTable a) = Context a
64+instance Projectable (ListTable context) where
65+ project f (ListTable a) = ListTable (hproject (apply f) a)
5066
51− fromColumns = ListTable
52− toColumns (ListTable a) = a
5367
68+instance (Table context a, context ~ context') =>
69+ Table context' (ListTable context a)
70+ where
71+ type Columns (ListTable context a) = HListTable (Columns a)
72+ type Context (ListTable context a) = Context a
73+ type FromExprs (ListTable context a) = [FromExprs a]
74+ type Transpose to (ListTable context a) = ListTable to (Transpose to a)
5475
55−instance Recontextualize from to a b =>
56− Recontextualize from to (ListTable a) (ListTable b)
76+ fromColumns = ListTable
77+ toColumns (ListTable a) = a
78+ fromResult = fmap (fromResult @_ @a) . hunvectorize unvectorizer
79+ toResult = hvectorize vectorizer . fmap (toResult @_ @a)
5780
5881
59−instance EqTable a => EqTable (ListTable a) where
82+instance (EqTable a, context ~ Expr) => EqTable (ListTable context a) where
6083 eqTable =
6184 hvectorize
62− (\SSpec {} (Identity dict) -> case dbTypeDict dict of
63− Dict -> case dbTypeNullity dict of
64− Null -> Dict
65− NotNull -> Dict)
85+ (\Spec {nullity} (Identity Dict) -> case nullity of
86+ Null -> Dict
87+ NotNull -> Dict)
6688 (Identity (eqTable @a))
6789
6890
69−instance OrdTable a => OrdTable (ListTable a) where
91+instance (OrdTable a, context ~ Expr) => OrdTable (ListTable context a) where
7092 ordTable =
7193 hvectorize
72− (\SSpec {} (Identity dict) -> case dbTypeDict dict of
73− Dict -> case dbTypeNullity dict of
74− Null -> Dict
75− NotNull -> Dict)
94+ (\Spec {nullity} (Identity Dict) -> case nullity of
95+ Null -> Dict
96+ NotNull -> Dict)
7697 (Identity (ordTable @a))
7798
7899
79−instance AltTable ListTable where
100+instance (ToExprs exprs a, context ~ Expr) =>
101+ ToExprs (ListTable context exprs) [a]
102+
103+
104+instance context ~ Expr => AltTable (ListTable context) where
80105 (<|>:) = (<>)
81106
82107
83−instance AlternativeTable ListTable where
108+instance context ~ Expr => AlternativeTable (ListTable context) where
84109 emptyTable = mempty
85110
86111
87−instance Table Expr a => Semigroup (ListTable a) where
88− ListTable as <> ListTable bs = ListTable $
89− happend (\_ _ (DB a) (DB b) -> DB (sappend a b)) as bs
112+instance (context ~ Expr, Table Expr a) => Semigroup (ListTable context a)
113+ where
114+ ListTable as <> ListTable bs = ListTable $ happend (const sappend) as bs
115+
116+
117+instance (context ~ Expr, Table Expr a) =>
118+ Monoid (ListTable context a)
119+ where
120+ mempty = ListTable $ hempty $ \Spec {info} -> sempty info
90121
91122
92−instance Table Expr a => Monoid (ListTable a) where
93− mempty = ListTable $ hempty $ \nullability info ->
94− DB (sempty nullability info)
123+-- | Project a single expression out of a 'ListTable'.
124+($*) :: Projecting a (Expr b)
125+ => Projection a (Expr b) -> ListTable Expr a -> Expr [b]
126+f $* ListTable a = hcolumn $ hproject (apply f) a
127+infixl 4 $*
95128
96129
97−listTable :: Table Expr a => [a] -> ListTable a
130+-- | Construct a @ListTable@ from a list of expressions.
131+listTable :: Table Expr a => [a] -> ListTable Expr a
98132listTable =
99133 ListTable .
100− hvectorize (\SSpec {info} -> DB . slistOf info . fmap unDB) .
134+ hvectorize (\Spec {info} -> slistOf info) .
101135 fmap toColumns
136+
137+
138+-- | Construct a 'ListTable' in the 'Name' context. This can be useful if you
139+-- have a 'ListTable' that you are storing in a table and need to construct a
140+-- 'TableSchema'.
141+nameListTable
142+ :: Table Name a
143+ => a -- ^ The names of the columns of elements of the list.
144+ -> ListTable Name a
145+nameListTable =
146+ ListTable .
147+ hvectorize (\_ (Identity (Name a)) -> Name a) .
148+ pure .
149+ toColumns
src/Rel8/Table/Maybe.hs+124−119
@@ -15,6 +15,7 @@ module Rel8.Table.Maybe
1515 ( MaybeTable(..)
1616 , maybeTable, nothingTable, justTable
1717 , isNothingTable, isJustTable
18+ , fromMaybeTable
1819 , ($?)
1920 , aggregateMaybeTable
2021 , nameMaybeTable
@@ -22,33 +23,35 @@ module Rel8.Table.Maybe
2223where
2324
2425-- base
25−import Data.Functor.Identity ( runIdentity )
26+import Data.Functor ( ($>) )
27+import Data.Functor.Identity ( Identity( Identity ) )
2628import Data.Kind ( Type )
29+import Data.Maybe ( fromMaybe, isJust )
2730import Prelude hiding ( null, undefined )
2831
32+-- comonad
33+import Control.Comonad ( extract )
34+
2935-- rel8
30−import Rel8.Aggregate ( Aggregate, unsafeMakeAggregate )
36+import Rel8.Aggregate ( Aggregate )
3137import Rel8.Expr ( Expr )
38+import Rel8.Expr.Aggregate ( groupByExpr )
3239import Rel8.Expr.Bool ( boolExpr )
3340import Rel8.Expr.Null ( isNull, isNonNull, null, nullify )
34−import Rel8.Expr.Opaleye ( fromPrimExpr, toPrimExpr )
35−import Rel8.Schema.Context.Label
36− ( Labelable, HLabelable, hlabeler, hunlabeler
37− )
38−import Rel8.Schema.Context.Nullify
39− ( Nullifiable, ConstrainTag
40− , HNullifiable, HConstrainTag
41− , hencodeTag, hdecodeTag
42− , hnullifier, hunnullifier
43− )
44−import Rel8.Schema.HTable ( HTable )
41+import Rel8.Kind.Context ( Reifiable )
42+import Rel8.Schema.Dict ( Dict( Dict ) )
43+import qualified Rel8.Schema.Kind as K
4544import Rel8.Schema.HTable.Identity ( HIdentity(..) )
4645import Rel8.Schema.HTable.Label ( hlabel, hunlabel )
4746import Rel8.Schema.HTable.Maybe ( HMaybeTable(..) )
48−import Rel8.Schema.HTable.Nullify ( hnullify, hunnullify )
4947import Rel8.Schema.Name ( Name )
50−import Rel8.Schema.Null ( Nullify, Nullity( Null, NotNull ), Sql, nullable )
51−import Rel8.Table ( Table, Columns, Context, fromColumns, toColumns )
48+import Rel8.Schema.Null ( Nullity( Null, NotNull ), Sql, nullable )
49+import qualified Rel8.Schema.Null as N
50+import Rel8.Table
51+ ( Table, Columns, Context, fromColumns, toColumns
52+ , FromExprs, fromResult, toResult
53+ , Transpose
54+ )
5255import Rel8.Table.Alternative
5356 ( AltTable, (<|>:)
5457 , AlternativeTable, emptyTable
@@ -56,14 +59,15 @@ import Rel8.Table.Alternative
5659import Rel8.Table.Bool ( bool )
5760import Rel8.Table.Eq ( EqTable, eqTable )
5861import Rel8.Table.Ord ( OrdTable, ordTable )
59−import Rel8.Table.Recontextualize ( Recontextualize )
60−import Rel8.Table.Tag ( Tag(..), fromExpr, fromName )
62+import Rel8.Table.Projection ( Projectable, project )
63+import Rel8.Table.Nullify ( Nullify, aggregateNullify, guard )
64+import Rel8.Table.Serialize ( ToExprs )
6165import Rel8.Table.Undefined ( undefined )
6266import Rel8.Type ( DBType )
63−import Rel8.Type.Tag ( MaybeTag )
67+import Rel8.Type.Tag ( MaybeTag( IsJust ) )
6468
6569-- semigroupoids
66−import Data.Functor.Apply ( Apply, (<.>), liftF2 )
70+import Data.Functor.Apply ( Apply, (<.>) )
6771import Data.Functor.Bind ( Bind, (>>-) )
6872
6973
@@ -75,167 +79,168 @@ import Data.Functor.Bind ( Bind, (>>-) )
7579-- entirely of nulls, you can't distinguish if you matched an all null row, or
7680-- if the match failed. For this reason @MaybeTable@ contains an extra field -
7781-- a "nullTag" - to track whether or not the outer join produced any rows.
78−type MaybeTable :: Type -> Type
79−data MaybeTable a = MaybeTable
80− { tag :: Tag "isJust" (Maybe MaybeTag)
81− , just :: a
82+type MaybeTable :: K.Context -> Type -> Type
83+data MaybeTable context a = MaybeTable
84+ { tag :: context (Maybe MaybeTag)
85+ , just :: Nullify context a
8286 }
8387 deriving stock Functor
8488
8589
86−instance Apply MaybeTable where
87− MaybeTable tag f <.> MaybeTable tag' a = MaybeTable (tag <> tag') (f a)
90+instance Projectable (MaybeTable context) where
91+ project f (MaybeTable tag a) = MaybeTable tag (project f a)
92+
93+
94+instance context ~ Expr => Apply (MaybeTable context) where
95+ MaybeTable tag f <.> MaybeTable tag' a = MaybeTable (tag <> tag') (f <.> a)
8896
8997
9098-- | Has the same behavior as the @Applicative@ instance for @Maybe@. See also:
9199-- 'Rel8.traverseMaybeTable'.
92−instance Applicative MaybeTable where
100+instance context ~ Expr => Applicative (MaybeTable context) where
93101 (<*>) = (<.>)
94102 pure = justTable
95103
96104
97−instance Bind MaybeTable where
98− MaybeTable tag a >>- f = case f a of
105+instance context ~ Expr => Bind (MaybeTable context) where
106+ MaybeTable tag a >>- f = case f (extract a) of
99107 MaybeTable tag' b -> MaybeTable (tag <> tag') b
100108
101109
102−-- | Has the same behavior as the @Monad@ instance for @Maybe@. See also:
103−-- 'Rel8.bindMaybeTable'.
104−instance Monad MaybeTable where
110+-- | Has the same behavior as the @Monad@ instance for @Maybe@.
111+instance context ~ Expr => Monad (MaybeTable context) where
105112 (>>=) = (>>-)
106113
107114
108−instance AltTable MaybeTable where
109− ma@(MaybeTable tag a) <|>: MaybeTable tag' b = MaybeTable
110− { tag = (tag <> tag')
111− { expr = boolExpr (expr tag) (expr tag') condition
112− }
113− , just = bool a b condition
114− }
115− where
116− condition = isNothingTable ma
115+instance context ~ Expr => AltTable (MaybeTable context) where
116+ ma <|>: mb = bool ma mb (isNothingTable ma)
117117
118118
119−instance AlternativeTable MaybeTable where
119+instance context ~ Expr => AlternativeTable (MaybeTable context) where
120120 emptyTable = nothingTable
121121
122122
123−instance (Table Expr a, Semigroup a) => Semigroup (MaybeTable a) where
123+instance (context ~ Expr, Table Expr a, Semigroup a) =>
124+ Semigroup (MaybeTable context a)
125+ where
124126 ma <> mb = maybeTable mb (\a -> maybeTable ma (justTable . (a <>)) mb) ma
125127
126128
127−instance (Table Expr a, Semigroup a) => Monoid (MaybeTable a) where
129+instance (context ~ Expr, Table Expr a, Semigroup a) =>
130+ Monoid (MaybeTable context a)
131+ where
128132 mempty = nothingTable
129133
130134
131−instance
132− ( Table context a
133− , Labelable context, Nullifiable context
134− , ConstrainTag context MaybeTag
135− ) => Table context (MaybeTable a)
135+instance (Table context a, Reifiable context, context ~ context') =>
136+ Table context' (MaybeTable context a)
136137 where
137− type Columns (MaybeTable a) = HMaybeTable (Columns a)
138− type Context (MaybeTable a) = Context a
138+ type Columns (MaybeTable context a) = HMaybeTable (Columns a)
139+ type Context (MaybeTable context a) = Context a
140+ type FromExprs (MaybeTable context a) = Maybe (FromExprs a)
141+ type Transpose to (MaybeTable context a) = MaybeTable to (Transpose to a)
142+
143+ toColumns MaybeTable {tag, just} = HMaybeTable
144+ { htag = hlabel $ HIdentity tag
145+ , hjust = hlabel $ guard tag isJust isNonNull $ toColumns just
146+ }
147+
148+ fromColumns HMaybeTable {htag, hjust} = MaybeTable
149+ { tag = unHIdentity $ hunlabel htag
150+ , just = fromColumns $ hunlabel hjust
151+ }
152+
153+ toResult ma = HMaybeTable
154+ { htag = hlabel (HIdentity (Identity (IsJust <$ ma)))
155+ , hjust = hlabel (toResult @_ @(Nullify context a) ma)
156+ }
139157
140− toColumns = toColumns1 toColumns
141− fromColumns = fromColumns1 fromColumns
158+ fromResult HMaybeTable {htag, hjust} = case hunlabel htag of
159+ HIdentity (Identity tag) -> tag $>
160+ fromMaybe err (fromResult @_ @(Nullify context a) (hunlabel hjust))
161+ where
162+ err = error "Maybe.fromColumns: mismatch between tag and data"
142163
143164
144−instance
145− ( Labelable from, Nullifiable from, ConstrainTag from MaybeTag
146− , Labelable to, Nullifiable to, ConstrainTag to MaybeTag
147− , Recontextualize from to a b
148− ) => Recontextualize from to (MaybeTable a) (MaybeTable b)
165+instance (EqTable a, context ~ Expr) => EqTable (MaybeTable context a) where
166+ eqTable = HMaybeTable
167+ { htag = hlabel (HIdentity Dict)
168+ , hjust = hlabel (eqTable @(Nullify context a))
169+ }
149170
150171
151−instance EqTable a => EqTable (MaybeTable a) where
152− eqTable = toColumns1 id (justTable (eqTable @a))
172+instance (OrdTable a, context ~ Expr) => OrdTable (MaybeTable context a) where
173+ ordTable = HMaybeTable
174+ { htag = hlabel (HIdentity Dict)
175+ , hjust = hlabel (ordTable @(Nullify context a))
176+ }
153177
154178
155−instance OrdTable a => OrdTable (MaybeTable a) where
156− ordTable = toColumns1 id (justTable (ordTable @a))
179+instance (ToExprs exprs a, context ~ Expr) =>
180+ ToExprs (MaybeTable context exprs) (Maybe a)
157181
158182
159183-- | Check if a @MaybeTable@ is absent of any row. Like 'Data.Maybe.isNothing'.
160−isNothingTable :: MaybeTable a -> Expr Bool
161−isNothingTable (MaybeTable tag _) = isNull (expr tag)
184+isNothingTable :: MaybeTable Expr a -> Expr Bool
185+isNothingTable (MaybeTable tag _) = isNull tag
162186
163187
164188-- | Check if a @MaybeTable@ contains a row. Like 'Data.Maybe.isJust'.
165−isJustTable :: MaybeTable a -> Expr Bool
166−isJustTable (MaybeTable tag _) = isNonNull (expr tag)
189+isJustTable :: MaybeTable Expr a -> Expr Bool
190+isJustTable (MaybeTable tag _) = isNonNull tag
167191
168192
169193-- | Perform case analysis on a 'MaybeTable'. Like 'maybe'.
170−maybeTable :: Table Expr b => b -> (a -> b) -> MaybeTable a -> b
171−maybeTable b f ma@(MaybeTable _ a) = bool (f a) b (isNothingTable ma)
194+maybeTable :: Table Expr b => b -> (a -> b) -> MaybeTable Expr a -> b
195+maybeTable b f ma@(MaybeTable _ a) = bool (f (extract a)) b (isNothingTable ma)
172196{-# INLINABLE maybeTable #-}
173197
174198
175199-- | The null table. Like 'Nothing'.
176−nothingTable :: Table Expr a => MaybeTable a
177−nothingTable = MaybeTable (fromExpr null) undefined
200+nothingTable :: Table Expr a => MaybeTable Expr a
201+nothingTable = MaybeTable null (pure undefined)
178202
179203
180204-- | Lift any table into 'MaybeTable'. Like 'Just'. Note you can also use
181205-- 'pure'.
182−justTable :: a -> MaybeTable a
183−justTable = MaybeTable (fromExpr mempty)
206+justTable :: a -> MaybeTable Expr a
207+justTable = MaybeTable mempty . pure
208+
209+
210+-- | 'Data.Maybe.fromMaybe' for 'MaybeTable's.
211+fromMaybeTable :: Table Expr a => a -> MaybeTable Expr a -> a
212+fromMaybeTable fallback = maybeTable fallback id
184213
185214
186215-- | Project a single expression out of a 'MaybeTable'. You can think of this
187216-- operator like the '$' operator, but it also has the ability to return
188217-- @null@.
189218($?) :: forall a b. Sql DBType b
190− => (a -> Expr b) -> MaybeTable a -> Expr (Nullify b)
219+ => (a -> Expr b) -> MaybeTable Expr a -> Expr (N.Nullify b)
191220f $? ma@(MaybeTable _ a) = case nullable @b of
192− Null -> boolExpr (f a) null (isNothingTable ma)
193− NotNull -> boolExpr (nullify (f a)) null (isNothingTable ma)
221+ Null -> boolExpr (f (extract a)) null (isNothingTable ma)
222+ NotNull -> boolExpr (nullify (f (extract a))) null (isNothingTable ma)
194223infixl 4 $?
195224
196225
226+-- | Lift an aggregating function to operate on a 'MaybeTable'.
227+-- @nothingTable@s and @justTable@s are grouped separately.
197228aggregateMaybeTable :: ()
198− => (a -> Aggregate b) -> MaybeTable a -> Aggregate (MaybeTable b)
199−aggregateMaybeTable f MaybeTable {tag = tag@Tag {aggregator, expr}, just} =
200− liftF2 MaybeTable (tag <$ aggregate) (f just)
201− where
202− aggregate = unsafeMakeAggregate toPrimExpr fromPrimExpr aggregator expr
203−
204−
205−nameMaybeTable :: Name (Maybe MaybeTag) -> a -> MaybeTable a
206−nameMaybeTable = MaybeTable . fromName
207−
208−
209−toColumns1 ::
210− ( HTable t
211− , HConstrainTag context MaybeTag
212− , HLabelable context
213− , HNullifiable context
214− )
215− => (a -> t context)
216− -> MaybeTable a
217− -> HMaybeTable t context
218−toColumns1 f MaybeTable {tag, just} = HMaybeTable
219− { htag
220− , hjust = hlabel hlabeler $ hnullify (hnullifier tag isNonNull) $ f just
221− }
222− where
223− htag = HIdentity (hencodeTag tag)
224−
225−
226−fromColumns1 ::
227− ( HTable t
228− , HConstrainTag context MaybeTag
229− , HLabelable context
230− , HNullifiable context
231− )
232− => (t context -> a)
233− -> HMaybeTable t context
234− -> MaybeTable a
235−fromColumns1 f HMaybeTable {htag = HIdentity htag, hjust} = MaybeTable
236− { tag
237− , just = f $ runIdentity $
238− hunnullify (\a -> pure . hunnullifier a) (hunlabel hunlabeler hjust)
239− }
240− where
241− tag = hdecodeTag htag
229+ => (exprs -> aggregates)
230+ -> MaybeTable Expr exprs
231+ -> MaybeTable Aggregate aggregates
232+aggregateMaybeTable f (MaybeTable tag a) =
233+ MaybeTable (groupByExpr tag) (aggregateNullify f a)
234+
235+
236+-- | Construct a 'MaybeTable' in the 'Name' context. This can be useful if you
237+-- have a 'MaybeTable' that you are storing in a table and need to construct a
238+-- 'TableSchema'.
239+nameMaybeTable
240+ :: Name (Maybe MaybeTag)
241+ -- ^ The name of the column to track whether a row is a 'justTable' or
242+ -- 'nothingTable'.
243+ -> a
244+ -- ^ Names of the columns in @a@.
245+ -> MaybeTable Name a
246+nameMaybeTable tag = MaybeTable tag . pure
src/Rel8/Table/Name.hs+37−26
@@ -1,14 +1,17 @@
1+{-# language DataKinds #-}
12{-# language FlexibleContexts #-}
3+{-# language FlexibleInstances #-}
4+{-# language MultiParamTypeClasses #-}
25{-# language NamedFieldPuns #-}
36{-# language ScopedTypeVariables #-}
47{-# language TypeApplications #-}
58{-# language TypeFamilies #-}
9+{-# language UndecidableInstances #-}
610{-# language ViewPatterns #-}
711
812module Rel8.Table.Name
913 ( namesFromLabels
1014 , namesFromLabelsWith
11− , showExprs
1215 , showLabels
1316 , showNames
1417 )
@@ -17,52 +20,60 @@ where
1720-- base
1821import Data.Foldable ( fold )
1922import Data.Functor.Const ( Const( Const ), getConst )
20−import Data.List.NonEmpty ( NonEmpty, intersperse )
23+import Data.List.NonEmpty ( NonEmpty, intersperse, nonEmpty )
24+import Data.Maybe ( fromMaybe )
2125import Prelude
2226
23−-- casing
24−import Text.Casing ( quietSnake )
25−
26−-- opaleye
27−import qualified Opaleye.Internal.HaskellDB.PrimQuery as Opaleye
28−
2927-- rel8
30−import Rel8.Expr ( Expr, Col(..) )
31−import Rel8.Expr.Opaleye ( toPrimExpr )
32−import Rel8.Kind.Labels ( renderLabels )
3328import Rel8.Schema.HTable ( htabulate, htabulateA, hfield, hspecs )
34−import Rel8.Schema.Name ( Name, Col(..) )
35−import Rel8.Schema.Spec ( SSpec(..) )
36−import Rel8.Table ( Table, Columns, Context, fromColumns, toColumns )
29+import Rel8.Schema.Name ( Name( Name ) )
30+import Rel8.Schema.Spec ( Spec(..) )
31+import Rel8.Table ( Table(..) )
3732
3833
34+-- | Construct a table in the 'Name' context containing the names of all
35+-- columns. Nested column names will be combined with @/@.
36+--
37+-- See also: 'namesFromLabelsWith'.
3938namesFromLabels :: Table Name a => a
4039namesFromLabels = namesFromLabelsWith go
4140 where
42− go = fold . intersperse "/" . fmap quietSnake
41+ go = fold . intersperse "/"
4342
4443
44+-- | Construct a table in the 'Name' context containing the names of all
45+-- columns. The supplied function can be used to transform column names.
46+--
47+-- This function can be used to generically derive the columns for a
48+-- 'TableSchema'. For example,
49+--
50+-- @
51+-- myTableSchema :: TableSchema (MyTable Name)
52+-- myTableSchema = TableSchema
53+-- { columns = namesFromLabelsWith last
54+-- }
55+-- @
56+--
57+-- will construct a 'TableSchema' where each columns names exactly corresponds
58+-- to the name of the Haskell field.
4559namesFromLabelsWith :: Table Name a
4660 => (NonEmpty String -> String) -> a
4761namesFromLabelsWith f = fromColumns $ htabulate $ \field ->
4862 case hfield hspecs field of
49− SSpec {labels} -> NameCol (f (renderLabels labels))
50−
51−
52−showExprs :: Table Expr a => a -> [(String, Opaleye.PrimExpr)]
53−showExprs as = case (namesFromLabels, toColumns as) of
54− (names, exprs) -> getConst $ htabulateA $ \field ->
55− case (hfield names field, hfield exprs field) of
56− (NameCol name, DB expr) -> Const [(name, toPrimExpr expr)]
63+ Spec {labels} -> Name (f (renderLabels labels))
5764
5865
5966showLabels :: forall a. Table (Context a) a => a -> [NonEmpty String]
6067showLabels _ = getConst $
6168 htabulateA @(Columns a) $ \field -> case hfield hspecs field of
62− SSpec {labels} -> Const [renderLabels labels]
69+ Spec {labels} -> Const (pure (renderLabels labels))
6370
6471
65−showNames :: forall a. Table Name a => a -> [String]
72+showNames :: forall a. Table Name a => a -> NonEmpty String
6673showNames (toColumns -> names) = getConst $
6774 htabulateA @(Columns a) $ \field -> case hfield names field of
68− NameCol name -> Const [name]
75+ Name name -> Const (pure name)
76+
77+
78+renderLabels :: [String] -> NonEmpty String
79+renderLabels labels = fromMaybe (pure "anon") (nonEmpty labels )
src/Rel8/Table/NonEmpty.hs+84−33
@@ -1,3 +1,4 @@
1+{-# language DataKinds #-}
12{-# language FlexibleContexts #-}
23{-# language FlexibleInstances #-}
34{-# language MultiParamTypeClasses #-}
@@ -10,8 +11,9 @@
1011
1112module Rel8.Table.NonEmpty
1213 ( NonEmptyTable(..)
13− , HNonEmptyTable
14+ , ($+)
1415 , nonEmptyTable
16+ , nameNonEmptyTable
1517 )
1618where
1719
@@ -19,74 +21,123 @@ where
1921import Data.Functor.Identity ( Identity( Identity ) )
2022import Data.Kind ( Type )
2123import Data.List.NonEmpty ( NonEmpty )
22−import Prelude
24+import Prelude hiding ( id )
2325
2426-- rel8
25−import Rel8.Expr ( Expr, Col(..) )
27+import Rel8.Expr ( Expr )
2628import Rel8.Expr.Array ( sappend1, snonEmptyOf )
2729import Rel8.Schema.Dict ( Dict( Dict ) )
2830import Rel8.Schema.HTable.NonEmpty ( HNonEmptyTable )
29−import Rel8.Schema.HTable.Vectorize ( happend, hvectorize )
31+import Rel8.Schema.HTable.Vectorize
32+ ( hvectorize, hunvectorize
33+ , happend
34+ , hproject, hcolumn
35+ )
36+import qualified Rel8.Schema.Kind as K
37+import Rel8.Schema.Name ( Name( Name ) )
3038import Rel8.Schema.Null ( Nullity( Null, NotNull ) )
31−import Rel8.Schema.Spec ( SSpec(..) )
32−import Rel8.Schema.Spec.ConstrainDBType ( dbTypeDict, dbTypeNullity )
33−import Rel8.Table ( Table, Context, Columns, fromColumns, toColumns )
39+import Rel8.Schema.Result ( vectorizer, unvectorizer )
40+import Rel8.Schema.Spec ( Spec(..) )
41+import Rel8.Table
42+ ( Table, Context, Columns, fromColumns, toColumns
43+ , FromExprs, fromResult, toResult
44+ , Transpose
45+ )
3446import Rel8.Table.Alternative ( AltTable, (<|>:) )
3547import Rel8.Table.Eq ( EqTable, eqTable )
3648import Rel8.Table.Ord ( OrdTable, ordTable )
37−import Rel8.Table.Recontextualize ( Recontextualize )
49+import Rel8.Table.Projection
50+ ( Projectable, Projecting, Projection, project, apply
51+ )
52+import Rel8.Table.Serialize ( ToExprs )
3853
3954
4055-- | A @NonEmptyTable@ value contains one or more instances of @a@. You
4156-- construct @NonEmptyTable@s with 'Rel8.some' or 'nonEmptyAgg'.
42−type NonEmptyTable :: Type -> Type
43−newtype NonEmptyTable a =
44− NonEmptyTable (HNonEmptyTable (Columns a) (Col (Context a)))
57+type NonEmptyTable :: K.Context -> Type -> Type
58+newtype NonEmptyTable context a =
59+ NonEmptyTable (HNonEmptyTable (Columns a) (Context a))
4560
4661
47−instance Table context a => Table context (NonEmptyTable a) where
48− type Columns (NonEmptyTable a) = HNonEmptyTable (Columns a)
49− type Context (NonEmptyTable a) = Context a
62+instance Projectable (NonEmptyTable context) where
63+ project f (NonEmptyTable a) = NonEmptyTable (hproject (apply f) a)
5064
51− fromColumns = NonEmptyTable
52− toColumns (NonEmptyTable a) = a
5365
66+instance (Table context a, context ~ context') =>
67+ Table context' (NonEmptyTable context a)
68+ where
69+ type Columns (NonEmptyTable context a) = HNonEmptyTable (Columns a)
70+ type Context (NonEmptyTable context a) = Context a
71+ type FromExprs (NonEmptyTable context a) = NonEmpty (FromExprs a)
72+ type Transpose to (NonEmptyTable context a) =
73+ NonEmptyTable to (Transpose to a)
5474
55−instance Recontextualize from to a b =>
56− Recontextualize from to (NonEmptyTable a) (NonEmptyTable b)
75+ fromColumns = NonEmptyTable
76+ toColumns (NonEmptyTable a) = a
77+ fromResult = fmap (fromResult @_ @a) . hunvectorize unvectorizer
78+ toResult = hvectorize vectorizer . fmap (toResult @_ @a)
5779
5880
59−instance EqTable a => EqTable (NonEmptyTable a) where
81+instance (EqTable a, context ~ Expr) =>
82+ EqTable (NonEmptyTable context a)
83+ where
6084 eqTable =
6185 hvectorize
62− (\SSpec {} (Identity dict) -> case dbTypeDict dict of
63− Dict -> case dbTypeNullity dict of
64− Null -> Dict
65− NotNull -> Dict)
86+ (\Spec {nullity} (Identity Dict) -> case nullity of
87+ Null -> Dict
88+ NotNull -> Dict)
6689 (Identity (eqTable @a))
6790
6891
69−instance OrdTable a => OrdTable (NonEmptyTable a) where
92+instance (OrdTable a, context ~ Expr) =>
93+ OrdTable (NonEmptyTable context a)
94+ where
7095 ordTable =
7196 hvectorize
72− (\SSpec {} (Identity dict) -> case dbTypeDict dict of
73− Dict -> case dbTypeNullity dict of
74− Null -> Dict
75− NotNull -> Dict)
97+ (\Spec {nullity} (Identity Dict) -> case nullity of
98+ Null -> Dict
99+ NotNull -> Dict)
76100 (Identity (ordTable @a))
77101
78102
79−instance AltTable NonEmptyTable where
103+instance (ToExprs exprs a, context ~ Expr) =>
104+ ToExprs (NonEmptyTable context exprs) (NonEmpty a)
105+
106+
107+instance context ~ Expr => AltTable (NonEmptyTable context) where
80108 (<|>:) = (<>)
81109
82110
83−instance Table Expr a => Semigroup (NonEmptyTable a) where
111+instance (Table Expr a, context ~ Expr) => Semigroup (NonEmptyTable context a)
112+ where
84113 NonEmptyTable as <> NonEmptyTable bs = NonEmptyTable $
85− happend (\_ _ (DB a) (DB b) -> DB (sappend1 a b)) as bs
114+ happend (const sappend1) as bs
115+
116+
117+-- | Project a single expression out of a 'NonEmptyTable'.
118+($+) :: Projecting a (Expr b)
119+ => Projection a (Expr b) -> NonEmptyTable Expr a -> Expr (NonEmpty b)
120+f $+ NonEmptyTable a = hcolumn $ hproject (apply f) a
121+infixl 4 $+
86122
87123
88−nonEmptyTable :: Table Expr a => NonEmpty a -> NonEmptyTable a
124+-- | Construct a @NonEmptyTable@ from a non-empty list of expressions.
125+nonEmptyTable :: Table Expr a => NonEmpty a -> NonEmptyTable Expr a
89126nonEmptyTable =
90127 NonEmptyTable .
91− hvectorize (\SSpec {info} -> DB . snonEmptyOf info . fmap unDB) .
128+ hvectorize (\Spec {info} -> snonEmptyOf info) .
92129 fmap toColumns
130+
131+
132+-- | Construct a 'NonEmptyTable' in the 'Name' context. This can be useful if
133+-- you have a 'NonEmptyTable' that you are storing in a table and need to
134+-- construct a 'TableSchema'.
135+nameNonEmptyTable
136+ :: Table Name a
137+ => a -- ^ The names of the columns of elements of the list.
138+ -> NonEmptyTable Name a
139+nameNonEmptyTable =
140+ NonEmptyTable .
141+ hvectorize (\_ (Identity (Name a)) -> Name a) .
142+ pure .
143+ toColumns
src/Rel8/Table/Null.hsnew file+147
@@ -0,0 +1,147 @@
1+{-# language DataKinds #-}
2+{-# language FlexibleContexts #-}
3+{-# language FlexibleInstances #-}
4+{-# language MultiParamTypeClasses #-}
5+{-# language ScopedTypeVariables #-}
6+{-# language StandaloneKindSignatures #-}
7+{-# language TypeApplications #-}
8+{-# language TypeFamilies #-}
9+{-# language UndecidableInstances #-}
10+
11+module Rel8.Table.Null
12+ ( NullTable(..)
13+ , nullableTable, nullTable, nullifyTable, unsafeUnnullifyTable
14+ , isNullTable, isNonNullTable
15+ , nameNullTable
16+ , toMaybeTable, toNullTable
17+ )
18+where
19+
20+-- base
21+import Data.Kind ( Type )
22+import Prelude hiding ( null, undefined )
23+
24+-- comonad
25+import Control.Comonad ( extract )
26+
27+-- rel8
28+import Rel8.Expr ( Expr )
29+import Rel8.Expr.Bool ( not_ )
30+import Rel8.Kind.Context ( Reifiable )
31+import qualified Rel8.Schema.Kind as K
32+import Rel8.Schema.Name ( Name )
33+import Rel8.Table
34+ ( Table, Columns, Context, fromColumns, toColumns
35+ , FromExprs, fromResult, toResult
36+ , Transpose
37+ )
38+import Rel8.Table.Alternative
39+ ( AltTable, (<|>:)
40+ , AlternativeTable, emptyTable
41+ )
42+import Rel8.Table.Bool ( bool )
43+import Rel8.Table.Eq ( EqTable, eqTable )
44+import Rel8.Table.Maybe ( MaybeTable, justTable, maybeTable, nothingTable )
45+import Rel8.Table.Nullify ( Nullify, isNull )
46+import Rel8.Table.Ord ( OrdTable, ordTable )
47+import Rel8.Table.Projection ( Projectable, project )
48+import Rel8.Table.Serialize ( ToExprs )
49+import Rel8.Table.Undefined ( undefined )
50+
51+
52+-- | @NullTable t@ is the table @t@, but where all the columns in @t@ have the
53+-- possibility of being 'Rel8.null'. This is very similar to
54+-- 'Rel8.MaybeTable', except that it does not use an extra tag field, so it
55+-- cannot distinguish between @Nothing@ and @Just Nothing@ if nested. In other
56+-- words, if all of the columns of the @t@ passed to @NullTable@ are already
57+-- nullable, then @NullTable@ has no effect.
58+type NullTable :: K.Context -> Type -> Type
59+newtype NullTable context a = NullTable (Nullify context a)
60+
61+
62+instance Projectable (NullTable context) where
63+ project f (NullTable a) = NullTable (project f a)
64+
65+
66+instance context ~ Expr => AltTable (NullTable context) where
67+ ma <|>: mb = bool ma mb (isNullTable ma)
68+
69+
70+instance context ~ Expr => AlternativeTable (NullTable context) where
71+ emptyTable = nullTable
72+
73+
74+instance (Table context a, Reifiable context, context ~ context') =>
75+ Table context' (NullTable context a)
76+ where
77+ type Columns (NullTable context a) = Columns (Nullify context a)
78+ type Context (NullTable context a) = Context (Nullify context a)
79+ type FromExprs (NullTable context a) = FromExprs (Nullify context a)
80+ type Transpose to (NullTable context a) = NullTable to (Transpose to a)
81+
82+ toColumns (NullTable a) = toColumns a
83+ fromColumns = NullTable . fromColumns
84+
85+ toResult = toResult @_ @(Nullify context a)
86+ fromResult = fromResult @_ @(Nullify context a)
87+
88+
89+instance (EqTable a, context ~ Expr) => EqTable (NullTable context a) where
90+ eqTable = eqTable @(Nullify context a)
91+
92+
93+instance (OrdTable a, context ~ Expr) => OrdTable (NullTable context a) where
94+ ordTable = ordTable @(Nullify context a)
95+
96+
97+instance (ToExprs exprs a, context ~ Expr) =>
98+ ToExprs (NullTable context exprs) (Maybe a)
99+
100+
101+-- | Check if any of the non-nullable fields of @a@ are 'Rel8.null' under the
102+-- 'NullTable'. Returns 'Rel8.false' if @a@ has no non-nullable fields.
103+isNullTable :: Table Expr a => NullTable Expr a -> Expr Bool
104+isNullTable (NullTable a) = isNull a
105+
106+
107+-- | The inverse of 'isNullTable'.
108+isNonNullTable :: Table Expr a => NullTable Expr a -> Expr Bool
109+isNonNullTable = not_ . isNullTable
110+
111+
112+-- | Like 'Rel8.nullable'.
113+nullableTable :: (Table Expr a, Table Expr b)
114+ => b -> (a -> b) -> NullTable Expr a -> b
115+nullableTable b f ma@(NullTable a) = bool (f (extract a)) b (isNullTable ma)
116+
117+
118+-- | The null table. Like 'Rel8.null'.
119+nullTable :: Table Expr a => NullTable Expr a
120+nullTable = NullTable (pure undefined)
121+
122+
123+-- | Lift any table into 'NullTable'. Like 'Rel8.nullify'.
124+nullifyTable :: a -> NullTable Expr a
125+nullifyTable = NullTable . pure
126+
127+
128+unsafeUnnullifyTable :: NullTable Expr a -> a
129+unsafeUnnullifyTable (NullTable a) = extract a
130+
131+
132+-- | Construct a 'NullTable' in the 'Name' context. This can be useful if you
133+-- have a 'NullTable' that you are storing in a table and need to construct a
134+-- 'TableSchema'.
135+nameNullTable :: a -> NullTable Name a
136+nameNullTable = NullTable . pure
137+
138+
139+-- | Convert a 'NullTable' to a 'MaybeTable'.
140+toMaybeTable :: Table Expr a => NullTable Expr a -> MaybeTable Expr a
141+toMaybeTable = nullableTable nothingTable justTable
142+
143+
144+-- | Convert a 'MaybeTable' to a 'NullTable'. Note that if the underlying @a@
145+-- has no non-nullable fields, this is a lossy conversion.
146+toNullTable :: Table Expr a => MaybeTable Expr a -> NullTable Expr a
147+toNullTable = maybeTable nullTable nullifyTable
src/Rel8/Table/Nullify.hsnew file+211
@@ -0,0 +1,211 @@
1+{-# language DataKinds #-}
2+{-# language FlexibleContexts #-}
3+{-# language FlexibleInstances #-}
4+{-# language LambdaCase #-}
5+{-# language MultiParamTypeClasses #-}
6+{-# language NamedFieldPuns #-}
7+{-# language ScopedTypeVariables #-}
8+{-# language StandaloneKindSignatures #-}
9+{-# language TypeApplications #-}
10+{-# language TypeFamilies #-}
11+{-# language UndecidableInstances #-}
12+
13+module Rel8.Table.Nullify
14+ ( Nullify
15+ , aggregateNullify
16+ , guard
17+ , isNull
18+ )
19+where
20+
21+-- base
22+import Control.Applicative ( liftA2 )
23+import Data.Functor.Const ( Const( Const ), getConst )
24+import Data.Functor.Identity ( runIdentity )
25+import Data.Kind ( Type )
26+import Prelude
27+
28+-- comonad
29+import Control.Comonad ( Comonad, duplicate, extract, ComonadApply, (<@>) )
30+
31+-- rel8
32+import Rel8.Aggregate ( Aggregate )
33+import Rel8.Expr ( Expr )
34+import Rel8.Expr.Bool ( (||.), false )
35+import qualified Rel8.Expr.Null as Expr
36+import Rel8.Kind.Context ( Reifiable, contextSing )
37+import Rel8.Schema.Context.Nullify
38+ ( Nullifiability( NAggregate, NExpr )
39+ , NonNullifiability
40+ , Nullifiable, nullifiability
41+ , nullifiableOrNot, absurd
42+ , guarder
43+ , nullifier
44+ , unnullifier
45+ )
46+import Rel8.Schema.Dict ( Dict( Dict ) )
47+import Rel8.Schema.HTable ( HTable )
48+import Rel8.Schema.HTable.Nullify
49+ ( HNullify, hnulls, hnullify, hunnullify
50+ , hguard
51+ , hproject
52+ )
53+import qualified Rel8.Schema.Kind as K
54+import Rel8.Schema.Null ( Nullity( NotNull, Null ) )
55+import qualified Rel8.Schema.Result as R
56+import Rel8.Table
57+ ( Table, Columns, Context, toColumns, fromColumns
58+ , FromExprs, fromResult, toResult
59+ , Transpose
60+ )
61+import Rel8.Schema.Spec ( Spec( Spec, nullity ) )
62+import Rel8.Table.Eq ( EqTable, eqTable )
63+import Rel8.Table.Ord ( OrdTable, ordTable )
64+import Rel8.Table.Projection ( Projectable, apply, project )
65+
66+-- semigroupoids
67+import Data.Functor.Apply ( Apply, (<.>), liftF2 )
68+import Data.Functor.Bind ( Bind, (>>-) )
69+import Data.Functor.Extend ( Extend, duplicated )
70+
71+
72+type Nullify :: K.Context -> Type -> Type
73+data Nullify context a
74+ = Table (Nullifiability context) a
75+ | Fields (NonNullifiability context) (HNullify (Columns a) (Context a))
76+
77+
78+instance Projectable (Nullify context) where
79+ project f = \case
80+ Table nullifiable a -> Table nullifiable (fromColumns (apply f (toColumns a)))
81+ Fields nonNullifiable a -> Fields nonNullifiable (hproject (apply f) a)
82+
83+
84+instance Nullifiable context => Functor (Nullify context) where
85+ fmap f = \case
86+ Table nullifiable a -> Table nullifiable (f a)
87+ Fields notNullifiable _ -> absurd nullifiability notNullifiable
88+
89+
90+instance Nullifiable context => Foldable (Nullify context) where
91+ foldMap f = \case
92+ Table _ a -> f a
93+ Fields notNullifiable _ -> absurd nullifiability notNullifiable
94+
95+
96+instance Nullifiable context => Traversable (Nullify context) where
97+ traverse f = \case
98+ Table nullifiable a -> Table nullifiable <$> f a
99+ Fields notNullifiable _ -> absurd nullifiability notNullifiable
100+
101+
102+instance Nullifiable context => Apply (Nullify context) where
103+ liftF2 f = \case
104+ Table nullifiable a -> \case
105+ Table _ b -> Table nullifiable (f a b)
106+ Fields notNullifiable _ -> absurd nullifiable notNullifiable
107+ Fields notNullifiable _ -> absurd nullifiability notNullifiable
108+
109+
110+instance Nullifiable context => Applicative (Nullify context) where
111+ pure = Table nullifiability
112+ liftA2 = liftF2
113+
114+
115+instance Nullifiable context => Bind (Nullify context) where
116+ Table _ a >>- f = f a
117+ Fields notNullifiable _ >>- _ = absurd nullifiability notNullifiable
118+
119+
120+instance Nullifiable context => Monad (Nullify context) where
121+ (>>=) = (>>-)
122+
123+
124+instance Nullifiable context => Extend (Nullify context) where
125+ duplicated = \case
126+ Table nullifiable a -> Table nullifiable (Table nullifiable a)
127+ Fields notNullifiable _ -> absurd nullifiability notNullifiable
128+
129+
130+instance Nullifiable context => Comonad (Nullify context) where
131+ extract = \case
132+ Table _ a -> a
133+ Fields notNullifiable _ -> absurd nullifiability notNullifiable
134+ duplicate = duplicated
135+
136+
137+instance Nullifiable context => ComonadApply (Nullify context) where
138+ (<@>) = (<.>)
139+
140+
141+instance (Table context a, Reifiable context, context ~ context') =>
142+ Table context' (Nullify context a)
143+ where
144+ type Columns (Nullify context a) = HNullify (Columns a)
145+ type Context (Nullify context a) = Context a
146+ type FromExprs (Nullify context a) = Maybe (FromExprs a)
147+ type Transpose to (Nullify context a) = Nullify to (Transpose to a)
148+
149+ fromColumns = case nullifiableOrNot contextSing of
150+ Left notNullifiable -> Fields notNullifiable
151+ Right nullifiable ->
152+ Table nullifiable .
153+ fromColumns .
154+ runIdentity .
155+ hunnullify (\spec -> pure . unnullifier nullifiable spec)
156+
157+ toColumns = \case
158+ Table nullifiable a -> hnullify (nullifier nullifiable) (toColumns a)
159+ Fields _ a -> a
160+
161+ fromResult = fmap (fromResult @_ @a) . hunnullify R.unnullifier
162+
163+ toResult =
164+ maybe (hnulls (const R.null)) (hnullify R.nullifier) .
165+ fmap (toResult @_ @a)
166+
167+
168+instance (EqTable a, context ~ Expr) => EqTable (Nullify context a) where
169+ eqTable = hnullify (\_ Dict -> Dict) (eqTable @a)
170+
171+
172+instance (OrdTable a, context ~ Expr) => OrdTable (Nullify context a) where
173+ ordTable = hnullify (\_ Dict -> Dict) (ordTable @a)
174+
175+
176+aggregateNullify :: ()
177+ => (exprs -> aggregates)
178+ -> Nullify Expr exprs
179+ -> Nullify Aggregate aggregates
180+aggregateNullify f = \case
181+ Table _ a -> Table NAggregate (f a)
182+ Fields notNullifiable _ -> absurd NExpr notNullifiable
183+
184+
185+guard :: (Reifiable context, HTable t)
186+ => context tag
187+ -> (tag -> Bool)
188+ -> (Expr tag -> Expr Bool)
189+ -> HNullify t context
190+ -> HNullify t context
191+guard tag isNonNull isNonNullExpr =
192+ hguard (guarder contextSing tag isNonNull isNonNullExpr)
193+
194+
195+isNull :: forall a. Table Expr a => Nullify Expr a -> Expr Bool
196+isNull =
197+ maybe false getAny .
198+ getConst .
199+ hunnullify (\Spec {nullity} a -> Const $ case nullity of
200+ NotNull -> Just $ Any $ Expr.isNull a
201+ Null -> Nothing) .
202+ toColumns
203+
204+
205+newtype Any = Any
206+ { getAny :: Expr Bool
207+ }
208+
209+
210+instance Semigroup Any where
211+ Any a <> Any b = Any (a ||. b)
src/Rel8/Table/Opaleye.hs+84−75
@@ -1,141 +1,150 @@
11{-# language BlockArguments #-}
2+{-# language DataKinds #-}
23{-# language DisambiguateRecordFields #-}
34{-# language FlexibleContexts #-}
45{-# language NamedFieldPuns #-}
6+{-# language RankNTypes #-}
57{-# language TypeFamilies #-}
68{-# language ViewPatterns #-}
79
10+{-# options_ghc -Wno-deprecations #-}
11+
812module Rel8.Table.Opaleye
913 ( aggregator
14+ , attributes
1015 , binaryspec
1116 , distinctspec
17+ , exprs
18+ , exprsWithNames
1219 , table
1320 , tableFields
1421 , unpackspec
1522 , valuesspec
23+ , view
1624 , castTable
1725 )
1826where
1927
2028-- base
21−import Prelude hiding ( undefined )
29+import Data.Functor.Const ( Const( Const ), getConst )
30+import Data.List.NonEmpty ( NonEmpty )
31+import Prelude
2232
2333-- opaleye
34+import qualified Opaleye.Adaptors as Opaleye
35+import qualified Opaleye.Field as Opaleye ( Field_ )
2436import qualified Opaleye.Internal.Aggregate as Opaleye
25−import qualified Opaleye.Internal.Binary as Opaleye
26−import qualified Opaleye.Internal.Distinct as Opaleye
2737import qualified Opaleye.Internal.HaskellDB.PrimQuery as Opaleye
28−import qualified Opaleye.Internal.PackMap as Opaleye
29−import qualified Opaleye.Internal.Unpackspec as Opaleye
3038import qualified Opaleye.Internal.Values as Opaleye
31−import qualified Opaleye.Internal.Table as Opaleye
39+import qualified Opaleye.Table as Opaleye
3240
3341-- profunctors
3442import Data.Profunctor ( dimap, lmap )
3543
3644-- rel8
37−import Rel8.Aggregate ( Aggregate( Aggregate ) )
38−import Rel8.Expr ( Expr, Col(..) )
45+import Rel8.Aggregate ( Aggregate( Aggregate ), Aggregates )
46+import Rel8.Expr ( Expr )
3947import Rel8.Expr.Opaleye
4048 ( fromPrimExpr, toPrimExpr
41− , traversePrimExpr
42− , fromColumn, toColumn
43− , scastExpr
49+ , scastExpr, traverseFieldP
4450 )
45−import Rel8.Kind.Necessity ( SNecessity( SRequired, SOptional ) )
46−import Rel8.Schema.HTable ( htabulateA, hfield, htraverse, hspecs, htabulate )
47−import Rel8.Schema.Insert ( Insert, Inserts, Col(..) )
48−import Rel8.Schema.Name ( Name, Selects, Col(..) )
49−import Rel8.Schema.Spec ( SSpec(..) )
50−import Rel8.Schema.Table ( TableSchema(..) )
51+import Rel8.Schema.HTable ( htabulateA, hfield, hspecs, htabulate,
52+ htraverseP, htraversePWithField )
53+import Rel8.Schema.Name ( Name( Name ), Selects, ppColumn )
54+import Rel8.Schema.Spec ( Spec(..) )
55+import Rel8.Schema.Table ( TableSchema(..), ppTable )
5156import Rel8.Table ( Table, fromColumns, toColumns )
52−import Rel8.Table.Undefined ( undefined )
57+import Rel8.Type.Information ( typeName )
5358
5459-- semigroupoids
5560import Data.Functor.Apply ( WrappedApplicative(..) )
61+import Data.Profunctor.Product ( ProductProfunctor )
62+
63+
64+aggregator :: Aggregates aggregates exprs => Opaleye.Aggregator aggregates exprs
65+aggregator = dimap toColumns fromColumns $
66+ htraverseP $
67+ lmap (\(Aggregate a) -> (a, ())) Opaleye.aggregatorApply
5668
5769
58−aggregator :: Opaleye.Aggregator (Aggregate exprs) exprs
59−aggregator = Opaleye.Aggregator $ Opaleye.PackMap $
60− \f (Aggregate (Opaleye.Aggregator (Opaleye.PackMap inner))) -> inner f ()
70+attributes :: Selects names exprs => TableSchema names -> exprs
71+attributes schema@TableSchema {columns} = fromColumns $ htabulate $ \field ->
72+ case hfield (toColumns columns) field of
73+ Name column -> fromPrimExpr $ Opaleye.ConstExpr $
74+ Opaleye.OtherLit $
75+ show (ppTable schema) <> "." <> show (ppColumn column)
76+
77+
78+fromOpaleyespec :: (ProductProfunctor p, Table Expr a)
79+ => p (Opaleye.Field_ n x) (Opaleye.Field_ n x)
80+ -> p a a
81+fromOpaleyespec x =
82+ dimap toColumns fromColumns (htraverseP (traverseFieldP x))
6183
6284
6385binaryspec :: Table Expr a => Opaleye.Binaryspec a a
64−binaryspec = Opaleye.Binaryspec $ Opaleye.PackMap $ \f (as, bs) ->
65− fmap fromColumns $ unwrapApplicative $ htabulateA $ \field ->
66− WrapApplicative $
67− case (hfield (toColumns as) field, hfield (toColumns bs) field) of
68− (DB a, DB b) -> DB . fromPrimExpr <$> f (toPrimExpr a, toPrimExpr b)
86+binaryspec = fromOpaleyespec Opaleye.binaryspecField
6987
7088
7189distinctspec :: Table Expr a => Opaleye.Distinctspec a a
72−distinctspec =
73− Opaleye.Distinctspec $ Opaleye.Aggregator $ Opaleye.PackMap $ \f ->
74− fmap fromColumns .
75− unwrapApplicative .
76− htraverse
77− (\(DB a) ->
78− WrapApplicative $ DB . fromPrimExpr <$> f (Nothing, toPrimExpr a)) .
79− toColumns
80−
81−
82−table ::(Selects names exprs, Inserts exprs inserts)
83− => TableSchema names -> Opaleye.Table inserts exprs
90+distinctspec = fromOpaleyespec Opaleye.distinctspecField
91+
92+
93+exprs :: Table Expr a => a -> NonEmpty Opaleye.PrimExpr
94+exprs (toColumns -> as) = getConst $ htabulateA $ \field ->
95+ case hfield as field of
96+ expr -> Const (pure (toPrimExpr expr))
97+
98+
99+exprsWithNames :: Selects names exprs
100+ => names -> exprs -> NonEmpty (String, Opaleye.PrimExpr)
101+exprsWithNames names as = getConst $ htabulateA $ \field ->
102+ case (hfield (toColumns names) field, hfield (toColumns as) field) of
103+ (Name name, expr) -> Const (pure (name, toPrimExpr expr))
104+
105+
106+table :: Selects names exprs => TableSchema names -> Opaleye.Table exprs exprs
84107table (TableSchema name schema columns) =
85108 case schema of
86− Nothing -> Opaleye.Table name (tableFields columns)
87− Just schemaName -> Opaleye.TableWithSchema schemaName name (tableFields columns)
109+ Nothing -> Opaleye.table name (tableFields columns)
110+ Just schemaName -> Opaleye.tableWithSchema schemaName name (tableFields columns)
88111
89112
90−tableFields :: (Selects names exprs, Inserts exprs inserts)
91− => names -> Opaleye.TableFields inserts exprs
113+tableFields :: Selects names exprs
114+ => names -> Opaleye.TableFields exprs exprs
92115tableFields (toColumns -> names) = dimap toColumns fromColumns $
93116 unwrapApplicative $ htabulateA $ \field -> WrapApplicative $
94− case hfield hspecs field of
95− specs -> case hfield names field of
96− name -> lmap (`hfield` field) (go specs name)
117+ case hfield names field of
118+ name -> lmap (`hfield` field) (go name)
97119 where
98− go :: SSpec spec -> Col Name spec -> Opaleye.TableFields (Col Insert spec) (Col Expr spec)
99− go SSpec {necessity} (NameCol name) = case necessity of
100− SRequired ->
101− lmap (\(RequiredInsert a) -> toColumn $ toPrimExpr a) $
102− DB . fromPrimExpr . fromColumn <$>
103− Opaleye.requiredTableField name
104− SOptional ->
105− lmap (\(OptionalInsert ma) -> toColumn . toPrimExpr <$> ma) $
106− DB . fromPrimExpr . fromColumn <$>
107− Opaleye.optionalTableField name
120+ go :: Name a -> Opaleye.TableFields (Expr a) (Expr a)
121+ go (Name name) =
122+ traverseFieldP $
123+ Opaleye.requiredTableField name
108124
109125
110126unpackspec :: Table Expr a => Opaleye.Unpackspec a a
111−unpackspec = Opaleye.Unpackspec $ Opaleye.PackMap $ \f ->
112− fmap fromColumns .
113− unwrapApplicative .
114− htraverse (\(DB a) -> WrapApplicative $ DB <$> traversePrimExpr f a) .
115− toColumns
127+unpackspec = fromOpaleyespec Opaleye.unpackspecField
116128{-# INLINABLE unpackspec #-}
117129
118130
119−valuesspec :: Table Expr a => Opaleye.ValuesspecSafe a a
120−valuesspec = Opaleye.ValuesspecSafe (toPackMap undefined) unpackspec
131+valuesspec :: Table Expr a => Opaleye.Valuesspec a a
132+valuesspec = dimap toColumns fromColumns $
133+ htraversePWithField (traverseFieldP . Opaleye.valuesspecFieldType . typeName)
134+ where typeName = Rel8.Type.Information.typeName . info . hfield hspecs
121135
122136
123−toPackMap :: Table Expr a
124− => a -> Opaleye.PackMap Opaleye.PrimExpr Opaleye.PrimExpr () a
125−toPackMap as = Opaleye.PackMap $ \f () ->
126− fmap fromColumns $
127− unwrapApplicative .
128− htraverse (\(DB a) -> WrapApplicative $ DB <$> traversePrimExpr f a) $
129− toColumns as
137+view :: Selects names exprs => names -> exprs
138+view columns = fromColumns $ htabulate $ \field ->
139+ case hfield (toColumns columns) field of
140+ Name column -> fromPrimExpr $ Opaleye.BaseTableAttrExpr column
130141
131142
132143-- | Transform a table by adding 'CAST' to all columns. This is most useful for
133144-- finalising a SELECT or RETURNING statement, guaranteed that the output
134145-- matches what is encoded in each columns TypeInformation.
135146castTable :: Table Expr a => a -> a
136−castTable (toColumns -> as) = fromColumns $ htabulate \i ->
137− case hfield hspecs i of
138− SSpec{info} ->
139− case hfield as i of
140− DB expr ->
141− DB (scastExpr info expr)
147+castTable (toColumns -> as) = fromColumns $ htabulate \field ->
148+ case hfield hspecs field of
149+ Spec {info} -> case hfield as field of
150+ expr -> scastExpr info expr
src/Rel8/Table/Ord.hs+17−47
@@ -10,7 +10,6 @@
1010{-# language TypeFamilies #-}
1111{-# language TypeOperators #-}
1212{-# language UndecidableInstances #-}
13−{-# language UndecidableSuperClasses #-}
1413{-# language ViewPatterns #-}
1514
1615module Rel8.Table.Ord
@@ -21,31 +20,24 @@ where
2120-- base
2221import Data.Functor.Const ( Const( Const ), getConst )
2322import Data.Kind ( Constraint, Type )
24−import Data.Proxy ( Proxy )
2523import GHC.Generics ( Rep )
2624import Prelude hiding ( seq )
2725
2826-- rel8
29−import Rel8.Expr ( Expr, Col(..) )
27+import Rel8.Expr ( Expr )
3028import Rel8.Expr.Bool ( (||.), (&&.), false, true )
3129import Rel8.Expr.Eq ( (==.) )
3230import Rel8.Expr.Ord ( (<.), (>.) )
3331import Rel8.FCF ( Eval, Exp )
3432import Rel8.Generic.Record ( Record )
35−import Rel8.Generic.Table ( GTable, GColumns, gtable )
33+import Rel8.Generic.Table.Record ( GTable, GColumns, gtable )
3634import Rel8.Schema.Dict ( Dict( Dict ) )
37−import Rel8.Schema.HTable
38− ( HTable, HConstrainTable
39− , htabulateA, hfield, hdicts
40− )
41−import Rel8.Schema.HTable.Type ( HType(..) )
42−import Rel8.Schema.Kind ( Context )
35+import Rel8.Schema.HTable ( htabulateA, hfield )
36+import Rel8.Schema.HTable.Identity ( HIdentity( HIdentity ) )
4337import Rel8.Schema.Null (Sql)
44−import Rel8.Schema.Spec.ConstrainDBType ( ConstrainDBType )
45−import Rel8.Table ( Table, Columns, toColumns, TColumns )
38+import Rel8.Table ( Columns, toColumns, TColumns )
4639import Rel8.Table.Bool ( bool )
4740import Rel8.Table.Eq ( EqTable )
48−import Rel8.Type.Eq ( DBEq )
4941import Rel8.Type.Ord ( DBOrd )
5042
5143
@@ -54,46 +46,24 @@ import Rel8.Type.Ord ( DBOrd )
5446-- columns in a 'Table' have an instance of 'DBOrd'".
5547type OrdTable :: Type -> Constraint
5648class EqTable a => OrdTable a where
57− ordTable :: Columns a (Dict (ConstrainDBType DBOrd))
49+ ordTable :: Columns a (Dict (Sql DBOrd))
5850
5951 default ordTable ::
60− ( GTable TOrdTable TColumns (Dict (ConstrainDBType DBOrd)) (Rep (Record a))
52+ ( GTable TOrdTable TColumns (Rep (Record a))
6153 , Columns a ~ GColumns TColumns (Rep (Record a))
6254 )
63− => Columns a (Dict (ConstrainDBType DBOrd))
64− ordTable = gtable @TOrdTable @TColumns @_ @(Rep (Record a)) table
55+ => Columns a (Dict (Sql DBOrd))
56+ ordTable = gtable @TOrdTable @TColumns @(Rep (Record a)) table
6557 where
66− table (_ :: Proxy x) = ordTable @x
58+ table (_ :: proxy x) = ordTable @x
6759
6860
6961data TOrdTable :: Type -> Exp Constraint
7062type instance Eval (TOrdTable a) = OrdTable a
7163
7264
73−instance
74− ( Table Expr (t (Expr :: Context))
75− , f ~ Expr
76− , HConstrainTable (Columns (t Expr)) (ConstrainDBType DBEq)
77− , HConstrainTable (Columns (t Expr)) (ConstrainDBType DBOrd)
78− )
79− => OrdTable (t f)
80− where
81− ordTable = hdicts @(Columns (t f)) @(ConstrainDBType DBOrd)
82−
83−
84−instance
85− ( HTable t
86− , f ~ Col Expr
87− , HConstrainTable t (ConstrainDBType DBEq)
88− , HConstrainTable t (ConstrainDBType DBOrd)
89− )
90− => OrdTable (t f)
91− where
92− ordTable = hdicts @(Columns (t f)) @(ConstrainDBType DBOrd)
93−
94−
9565instance Sql DBOrd a => OrdTable (Expr a) where
96− ordTable = HType Dict
66+ ordTable = HIdentity Dict
9767
9868
9969instance (OrdTable a, OrdTable b) => OrdTable (a, b)
@@ -128,7 +98,7 @@ instance
12898(toColumns -> as) <: (toColumns -> bs) =
12999 foldr @[] go false $ getConst $ htabulateA $ \field ->
130100 case (hfield as field, hfield bs field) of
131− (DB a, DB b) -> case hfield (ordTable @a) field of
101+ (a, b) -> case hfield (ordTable @a) field of
132102 Dict -> Const [(a <. b, a ==. b)]
133103 where
134104 go (lt, eq) a = lt ||. (eq &&. a)
@@ -141,7 +111,7 @@ infix 4 <:
141111(toColumns -> as) <=: (toColumns -> bs) =
142112 foldr @[] go true $ getConst $ htabulateA $ \field ->
143113 case (hfield as field, hfield bs field) of
144− (DB a, DB b) -> case hfield (ordTable @a) field of
114+ (a, b) -> case hfield (ordTable @a) field of
145115 Dict -> Const [(a <. b, a ==. b)]
146116 where
147117 go (lt, eq) a = lt ||. (eq &&. a)
@@ -154,7 +124,7 @@ infix 4 <=:
154124(toColumns -> as) >: (toColumns -> bs) =
155125 foldr @[] go false $ getConst $ htabulateA $ \field ->
156126 case (hfield as field, hfield bs field) of
157− (DB a, DB b) -> case hfield (ordTable @a) field of
127+ (a, b) -> case hfield (ordTable @a) field of
158128 Dict -> Const [(a >. b, a ==. b)]
159129 where
160130 go (gt, eq) a = gt ||. (eq &&. a)
@@ -167,7 +137,7 @@ infix 4 >:
167137(toColumns -> as) >=: (toColumns -> bs) =
168138 foldr @[] go true $ getConst $ htabulateA $ \field ->
169139 case (hfield as field, hfield bs field) of
170− (DB a, DB b) -> case hfield (ordTable @a) field of
140+ (a, b) -> case hfield (ordTable @a) field of
171141 Dict -> Const [(a >. b, a ==. b)]
172142 where
173143 go (gt, eq) a = gt ||. (eq &&. a)
@@ -176,9 +146,9 @@ infix 4 >=:
176146
177147-- | Given two 'Table's, return the table that sorts before the other.
178148least :: OrdTable a => a -> a -> a
179−least a b = bool a b (a <: b)
149+least a b = bool b a (a <: b)
180150
181151
182152-- | Given two 'Table's, return the table that sorts after the other.
183153greatest :: OrdTable a => a -> a -> a
184−greatest a b = bool a b (a >: b)
154+greatest a b = bool b a (a >: b)
src/Rel8/Table/Order.hs+13−16
@@ -1,4 +1,5 @@
11{-# language DataKinds #-}
2+{-# language NamedFieldPuns #-}
23{-# language ScopedTypeVariables #-}
34{-# language TypeApplications #-}
45{-# language TypeFamilies #-}
@@ -15,16 +16,14 @@ import Data.Functor.Contravariant ( (>$<), contramap )
1516import Prelude
1617
1718-- rel8
18−import Rel8.Expr ( unDB )
1919import Rel8.Expr.Order ( asc, desc, nullsFirst, nullsLast )
2020import Rel8.Order ( Order )
2121import Rel8.Schema.Dict ( Dict( Dict ) )
2222import Rel8.Schema.HTable (htabulateA, hfield, hspecs)
2323import Rel8.Schema.Null ( Nullity( Null, NotNull ) )
24−import Rel8.Schema.Spec ( SSpec( SSpec ) )
25−import Rel8.Schema.Spec.ConstrainDBType ( dbTypeDict, dbTypeNullity )
24+import Rel8.Schema.Spec ( Spec( Spec, nullity ) )
2625import Rel8.Table ( Columns, toColumns )
27−import Rel8.Table.Ord
26+import Rel8.Table.Ord ( OrdTable, ordTable )
2827
2928
3029-- | Construct an 'Order' for a 'Table' by sorting all columns into ascending
@@ -32,12 +31,11 @@ import Rel8.Table.Ord
3231ascTable :: forall a. OrdTable a => Order a
3332ascTable = contramap toColumns $ getConst $
3433 htabulateA @(Columns a) $ \field -> case hfield hspecs field of
35− SSpec {} -> case hfield (ordTable @a) field of
36− dict@Dict -> case dbTypeDict dict of
37− Dict -> Const $ unDB . (`hfield` field) >$<
38− case dbTypeNullity dict of
39− Null -> nullsFirst asc
40− NotNull -> asc
34+ Spec {nullity} -> case hfield (ordTable @a) field of
35+ Dict -> Const $ (`hfield` field) >$<
36+ case nullity of
37+ Null -> nullsFirst asc
38+ NotNull -> asc
4139
4240
4341-- | Construct an 'Order' for a 'Table' by sorting all columns into descending
@@ -45,9 +43,8 @@ ascTable = contramap toColumns $ getConst $
4543descTable :: forall a. OrdTable a => Order a
4644descTable = contramap toColumns $ getConst $
4745 htabulateA @(Columns a) $ \field -> case hfield hspecs field of
48− SSpec {} -> case hfield (ordTable @a) field of
49− dict@Dict -> case dbTypeDict dict of
50− Dict -> Const $ unDB . (`hfield` field) >$<
51− case dbTypeNullity dict of
52− Null -> nullsLast desc
53− NotNull -> desc
46+ Spec {nullity} -> case hfield (ordTable @a) field of
47+ Dict -> Const $ (`hfield` field) >$<
48+ case nullity of
49+ Null -> nullsLast desc
50+ NotNull -> desc
src/Rel8/Table/Projection.hsnew file+73
@@ -0,0 +1,73 @@
1+{-# language FlexibleContexts #-}
2+{-# language FlexibleInstances #-}
3+{-# language MonoLocalBinds #-}
4+{-# language MultiParamTypeClasses #-}
5+{-# language StandaloneKindSignatures #-}
6+{-# language UndecidableInstances #-}
7+
8+module Rel8.Table.Projection
9+ ( Projection
10+ , Projectable( project )
11+ , Biprojectable( biproject )
12+ , Projecting
13+ , apply
14+ )
15+where
16+
17+-- base
18+import Data.Kind ( Constraint, Type )
19+import Prelude
20+
21+-- rel8
22+import Rel8.Schema.Field ( Field( Field ), fields )
23+import Rel8.Schema.HTable ( hfield, htabulate )
24+import Rel8.Table ( Columns, Context, Transpose, toColumns )
25+import Rel8.Table.Transpose ( Transposes )
26+
27+
28+-- | The constraint @'Projecting' a b@ ensures that @'Projection' a b@ is a
29+-- usable 'Projection'.
30+type Projecting :: Type -> Type -> Constraint
31+class
32+ ( Transposes (Context a) (Field a) a (Transpose (Field a) a)
33+ , Transposes (Context a) (Field a) b (Transpose (Field a) b)
34+ )
35+ => Projecting a b
36+instance
37+ ( Transposes (Context a) (Field a) a (Transpose (Field a) a)
38+ , Transposes (Context a) (Field a) b (Transpose (Field a) b)
39+ )
40+ => Projecting a b
41+
42+
43+-- | A @'Projection' a b@s is a special type of function @a -> b@ whereby the
44+-- resulting @b@ is guaranteed to be composed only from columns contained in
45+-- @a@.
46+type Projection :: Type -> Type -> Type
47+type Projection a b = Transpose (Field a) a -> Transpose (Field a) b
48+
49+
50+-- | @'Projectable' f@ means that @f@ is a kind of functor on 'Rel8.Table's
51+-- that allows the mapping of a 'Projection' over its underlying columns.
52+type Projectable :: (Type -> Type) -> Constraint
53+class Projectable f where
54+ -- | Map a 'Projection' over @f@.
55+ project :: Projecting a b
56+ => Projection a b -> f a -> f b
57+
58+
59+-- | @'Biprojectable' p@ means that @p@ is a kind of bifunctor on
60+-- 'Rel8.Table's that allows the mapping of a pair of 'Projection's over its
61+-- underlying columns.
62+type Biprojectable :: (Type -> Type -> Type) -> Constraint
63+class Biprojectable p where
64+ -- | Map a pair of 'Projection's over @p@.
65+ biproject :: (Projecting a b, Projecting c d)
66+ => Projection a b -> Projection c d -> p a c -> p b d
67+
68+
69+apply :: Projecting a b
70+ => Projection a b -> Columns a context -> Columns b context
71+apply f a = case toColumns (f fields) of
72+ bs -> htabulate $ \field -> case hfield bs field of
73+ Field field' -> hfield a field'
src/Rel8/Table/Recontextualize.hsdeleted−90
@@ -1,90 +0,0 @@
1−{-# language DataKinds #-}
2−{-# language FlexibleInstances #-}
3−{-# language FunctionalDependencies #-}
4−{-# language StandaloneKindSignatures #-}
5−{-# language TypeFamilies #-}
6−{-# language UndecidableInstances #-}
7−{-# language UndecidableSuperClasses #-}
8−
9−module Rel8.Table.Recontextualize
10− ( Recontextualize
11− )
12−where
13−
14−-- base
15−import Data.Functor.Identity ( Identity )
16−import Data.Kind ( Constraint, Type )
17−import Prelude ()
18−
19−-- rel8
20−import Rel8.Schema.Context ( Col )
21−import Rel8.Schema.Context.Label ( Labelable )
22−import Rel8.Schema.HTable ( HTable )
23−import qualified Rel8.Schema.Kind as K
24−import Rel8.Schema.Null ( Sql )
25−import Rel8.Schema.Result ( Result )
26−import Rel8.Table ( Table, Congruent )
27−import Rel8.Type ( DBType )
28−
29−
30−type Recontextualize :: K.Context -> K.Context -> Type -> Type -> Constraint
31−class
32− ( Table from a
33− , Table to b
34− , Congruent a b
35− , Recontextualize from from a a
36− , Recontextualize to to b b
37− , Recontextualize to from b a
38− ) => Recontextualize from to a b
39− | a -> from
40− , b -> to
41− , a to -> b
42− , b from -> a
43−
44−
45−instance Sql DBType a => Recontextualize Result Result (Identity a) (Identity a)
46−
47−
48−instance HTable t => Recontextualize from to (t (Col from)) (t (Col to))
49−
50−
51−instance
52− ( Table from (t from)
53− , Table to (t to)
54− , Congruent (t from) (t to)
55− ) => Recontextualize from to (t from) (t to)
56−
57−
58−instance
59− ( Recontextualize from to a1 b1
60− , Recontextualize from to a2 b2
61− , Labelable from
62− , Labelable to
63− ) => Recontextualize from to (a1, a2) (b1, b2)
64−
65−
66−instance
67− ( Recontextualize from to a1 b1
68− , Recontextualize from to a2 b2
69− , Recontextualize from to a3 b3
70− , Labelable from, Labelable to
71− ) => Recontextualize from to (a1, a2, a3) (b1, b2, b3)
72−
73−
74−instance
75− ( Recontextualize from to a1 b1
76− , Recontextualize from to a2 b2
77− , Recontextualize from to a3 b3
78− , Recontextualize from to a4 b4
79− , Labelable from, Labelable to
80− ) => Recontextualize from to (a1, a2, a3, a4) (b1, b2, b3, b4)
81−
82−
83−instance
84− ( Recontextualize from to a1 b1
85− , Recontextualize from to a2 b2
86− , Recontextualize from to a3 b3
87− , Recontextualize from to a4 b4
88− , Recontextualize from to a5 b5
89− , Labelable from, Labelable to
90− ) => Recontextualize from to (a1, a2, a3, a4, a5) (b1, b2, b3, b4, b5)
src/Rel8/Table/Rel8able.hsnew file+92
@@ -0,0 +1,92 @@
1+{-# language DataKinds #-}
2+{-# language FlexibleInstances #-}
3+{-# language MultiParamTypeClasses #-}
4+{-# language ScopedTypeVariables #-}
5+{-# language StandaloneKindSignatures #-}
6+{-# language TypeApplications #-}
7+{-# language TypeFamilies #-}
8+{-# language UndecidableInstances #-}
9+
10+{-# options_ghc -fno-warn-orphans #-}
11+
12+module Rel8.Table.Rel8able
13+ (
14+ )
15+where
16+
17+-- base
18+import Prelude ()
19+
20+-- rel8
21+import Rel8.Expr ( Expr )
22+import qualified Rel8.Kind.Algebra as K
23+import Rel8.Kind.Context ( Reifiable, contextSing )
24+import Rel8.Generic.Rel8able
25+ ( Rel8able, Algebra
26+ , GColumns, gfromColumns, gtoColumns
27+ , GFromExprs, gfromResult, gtoResult
28+ )
29+import qualified Rel8.Schema.Kind as K
30+import Rel8.Schema.HTable ( HConstrainTable, hdicts )
31+import Rel8.Schema.Null ( Sql )
32+import Rel8.Schema.Result ( Result )
33+import Rel8.Table
34+ ( Table, Columns, Context, fromColumns, toColumns
35+ , FromExprs, fromResult, toResult
36+ , Transpose
37+ )
38+import Rel8.Table.ADT ( ADT )
39+import Rel8.Table.Eq ( EqTable, eqTable )
40+import Rel8.Table.Ord ( OrdTable, ordTable )
41+import Rel8.Table.Serialize ( ToExprs )
42+import Rel8.Type.Eq ( DBEq )
43+import Rel8.Type.Ord ( DBOrd )
44+
45+
46+instance (Rel8able t, Reifiable context, context ~ context') =>
47+ Table context' (t context)
48+ where
49+ type Columns (t context) = GColumns t
50+ type Context (t context) = context
51+ type FromExprs (t context) = GFromExprs t
52+ type Transpose to (t context) = t to
53+
54+ fromColumns = gfromColumns contextSing
55+ toColumns = gtoColumns contextSing
56+ fromResult = gfromResult @t
57+ toResult = gtoResult @t
58+
59+
60+instance
61+ ( context ~ Expr
62+ , Rel8able t
63+ , HConstrainTable (Columns (t context)) (Sql DBEq)
64+ )
65+ => EqTable (t context)
66+ where
67+ eqTable = hdicts @(Columns (t context)) @(Sql DBEq)
68+
69+
70+instance
71+ ( context ~ Expr
72+ , Rel8able t
73+ , HConstrainTable (Columns (t context)) (Sql DBEq)
74+ , HConstrainTable (Columns (t context)) (Sql DBOrd)
75+ )
76+ => OrdTable (t context)
77+ where
78+ ordTable = hdicts @(Columns (t context)) @(Sql DBOrd)
79+
80+
81+instance
82+ ( Rel8able t', t' ~ Choose (Algebra t) t
83+ , x ~ t' Expr
84+ , result ~ Result
85+ )
86+ => ToExprs x (t result)
87+
88+
89+type Choose :: K.Algebra -> K.Rel8able -> K.Rel8able
90+type family Choose algebra t where
91+ Choose 'K.Sum t = ADT t
92+ Choose 'K.Product t = t
src/Rel8/Table/Serialize.hs+19−241
@@ -1,7 +1,4 @@
11{-# language AllowAmbiguousTypes #-}
2−{-# language DataKinds #-}
3−{-# language DefaultSignatures #-}
4−{-# language DisambiguateRecordFields #-}
52{-# language FlexibleContexts #-}
63{-# language FlexibleInstances #-}
74{-# language FunctionalDependencies #-}
@@ -10,178 +7,54 @@
107{-# language StandaloneKindSignatures #-}
118{-# language TypeApplications #-}
129{-# language TypeFamilies #-}
13−{-# language TypeOperators #-}
1410{-# language UndecidableInstances #-}
1511
1612module Rel8.Table.Serialize
17− ( Serializable, lit, parse
18− , Encodes, litTable
19− , ToExprs(..)
20− , FromExprs
13+ ( Serializable, lit, litHTable, parse
14+ , ToExprs
2115 )
2216where
2317
2418-- base
25−import Data.Bifunctor ( bimap )
19+import Data.Functor.Identity ( Identity( Identity ) )
2620import Data.Kind ( Constraint, Type )
2721import Data.List.NonEmpty ( NonEmpty )
28−import GHC.Generics
29− ( Generic, Rep, from, to
30− , (:*:)( (:*:) ), K1( K1 ), M1( M1 ), Meta( MetaSel ), D, C, S
31− )
32−import GHC.TypeLits ( KnownSymbol )
3322import Prelude
3423
3524-- hasql
3625import qualified Hasql.Decoders as Hasql
3726
3827-- rel8
39−import Rel8.Expr ( Expr, Col(..) )
28+import Rel8.Expr ( Expr )
4029import Rel8.Expr.Serialize ( slitExpr, sparseValue )
41−import Rel8.Generic.Record ( Record(..) )
42−import Rel8.Generic.Table ( GColumns )
43−import Rel8.Schema.Context ( Col(..) )
44−import Rel8.Schema.Context.Label ( labeler, unlabeler )
4530import Rel8.Schema.HTable ( HTable, htabulate, htabulateA, hfield, hspecs )
46−import Rel8.Schema.HTable.Label ( HLabel, hlabel, hunlabel )
47−import Rel8.Schema.HTable.Product ( HProduct(..) )
48−import Rel8.Schema.HTable.Type ( HType(..) )
4931import Rel8.Schema.Null ( NotNull, Sql )
5032import Rel8.Schema.Result ( Result )
51−import Rel8.Schema.Spec ( SSpec(..), KnownSpec )
52−import Rel8.Table ( Table, Columns, fromColumns, toColumns, TColumns )
53−import Rel8.Table.Either ( EitherTable )
54−import Rel8.Table.List ( ListTable )
55−import Rel8.Table.Maybe ( MaybeTable )
56−import Rel8.Table.NonEmpty ( NonEmptyTable )
57−import Rel8.Table.Recontextualize ( Recontextualize )
58−import Rel8.Table.These ( TheseTable )
33+import Rel8.Schema.Spec ( Spec(..) )
34+import Rel8.Table ( Table, fromColumns, FromExprs, fromResult, toResult )
5935import Rel8.Type ( DBType )
6036
6137-- semigroupoids
6238import Data.Functor.Apply ( WrappedApplicative(..) )
6339
64−-- these
65−import Data.These ( These )
66−
6740
41+-- | @ToExprs exprs a@ is evidence that the types @exprs@ and @a@ describe
42+-- essentially the same type, but @exprs@ is in the 'Expr' context, and @a@ is
43+-- a normal Haskell type.
6844type ToExprs :: Type -> Type -> Constraint
69−class Table Expr exprs => ToExprs exprs a where
70− fromResult :: Columns exprs (Col Result) -> a
71− toResult :: a -> Columns exprs (Col Result)
72−
73− default fromResult ::
74− ( Generic (Record a)
75− , GToExprs (Rep (Record exprs)) (Rep (Record a))
76− , Columns exprs ~ GColumns TColumns (Rep (Record exprs))
77− )
78− => Columns exprs (Col Result) -> a
79− fromResult = unrecord . to . gfromResult @(Rep (Record exprs))
80−
81− default toResult ::
82− ( Generic (Record a)
83− , GToExprs (Rep (Record exprs)) (Rep (Record a))
84− , Columns exprs ~ GColumns TColumns (Rep (Record exprs))
85− )
86− => a -> Columns exprs (Col Result)
87− toResult = gtoResult @(Rep (Record exprs)) . from . Record
88−
89−
90−type GToExprs :: (Type -> Type) -> (Type -> Type) -> Constraint
91−class GToExprs exprs rep where
92− gfromResult :: GColumns TColumns exprs (Col Result) -> rep x
93− gtoResult :: rep x -> GColumns TColumns exprs (Col Result)
94−
95−
96−instance GToExprs exprs rep => GToExprs (M1 D c exprs) (M1 D c rep) where
97− gfromResult = M1 . gfromResult @exprs
98− gtoResult (M1 a) = gtoResult @exprs a
45+class Table Expr exprs => ToExprs exprs a
9946
10047
101−instance GToExprs exprs rep => GToExprs (M1 C c exprs) (M1 C c rep) where
102− gfromResult = M1 . gfromResult @exprs
103− gtoResult (M1 a) = gtoResult @exprs a
104−
105−
106−instance (GToExprs exprs1 rep1, GToExprs exprs2 rep2) =>
107− GToExprs (exprs1 :*: exprs2) (rep1 :*: rep2)
108− where
109− gfromResult (HProduct a b) = gfromResult @exprs1 a :*: gfromResult @exprs2 b
110− gtoResult (a :*: b) = HProduct (gtoResult @exprs1 a) (gtoResult @exprs2 b)
111−
112−
113−instance
114− ( ToExprs exprs a
115− , KnownSymbol label
116− , GColumns TColumns (M1 S meta k1) ~ HLabel label (Columns exprs)
117− , meta ~ 'MetaSel ('Just label) _su _ss _ds
118− , k1 ~ K1 i exprs
119− , k1' ~ K1 i a
120− )
121− => GToExprs (M1 S meta k1) (M1 S meta k1')
122− where
123− gfromResult = M1 . K1 . fromResult @exprs . hunlabel unlabeler
124− gtoResult (M1 (K1 a)) = hlabel labeler (toResult @exprs a)
125−
48+instance {-# OVERLAPPABLE #-} (Sql DBType a, x ~ Expr a) => ToExprs x a
12649
127−instance {-# OVERLAPPABLE #-} (Sql DBType a, x ~ Expr a) => ToExprs x a where
128− fromResult (HType (Result a)) = a
129− toResult = HType . Result
13050
131−
132−instance (Sql DBType a, x ~ [a]) => ToExprs (Expr x) [a] where
133− fromResult (HType (Result a)) = a
134− toResult = HType . Result
51+instance (Sql DBType a, x ~ [a]) => ToExprs (Expr x) [a]
13552
13653
13754instance (Sql DBType a, NotNull a, x ~ Maybe a) => ToExprs (Expr x) (Maybe a)
138− where
139− fromResult (HType (Result a)) = a
140− toResult = HType . Result
14155
14256
14357instance (Sql DBType a, NotNull a, x ~ NonEmpty a) => ToExprs (Expr x) (NonEmpty a)
144− where
145− fromResult (HType (Result a)) = a
146− toResult = HType . Result
147−
148−
149−instance (ToExprs exprs1 a, ToExprs exprs2 b, x ~ EitherTable exprs1 exprs2) =>
150− ToExprs x (Either a b)
151− where
152− fromResult =
153− bimap (fromResult @exprs1) (fromResult @exprs2) .
154− fromColumns
155− toResult =
156− toColumns .
157− bimap (toResult @exprs1) (toResult @exprs2)
158−
159−
160−instance ToExprs exprs a => ToExprs (ListTable exprs) [a] where
161− fromResult = fmap (fromResult @exprs) . fromColumns
162− toResult = toColumns . fmap (toResult @exprs)
163−
164−
165−instance ToExprs exprs a => ToExprs (MaybeTable exprs) (Maybe a) where
166− fromResult = fmap (fromResult @exprs) . fromColumns
167− toResult = toColumns . fmap (toResult @exprs)
168−
169−
170−instance ToExprs exprs a => ToExprs (NonEmptyTable exprs) (NonEmpty a)
171− where
172− fromResult = fmap (fromResult @exprs) . fromColumns
173− toResult = toColumns . fmap (toResult @exprs)
174−
175−
176−instance (ToExprs exprs1 a, ToExprs exprs2 b, x ~ TheseTable exprs1 exprs2) =>
177− ToExprs x (These a b)
178− where
179− fromResult =
180− bimap (fromResult @exprs1) (fromResult @exprs2) .
181− fromColumns
182− toResult =
183− toColumns .
184− bimap (toResult @exprs1) (toResult @exprs2)
18558
18659
18760instance (ToExprs exprs1 a, ToExprs exprs2 b, x ~ (exprs1, exprs2)) =>
@@ -243,54 +116,6 @@ instance
243116 => ToExprs x (a, b, c, d, e, f, g)
244117
245118
246−instance (HTable t, result ~ Col Result, x ~ t (Col Expr)) =>
247− ToExprs x (t result)
248− where
249− fromResult = id
250− toResult = id
251−
252−
253−instance (Recontextualize Result Expr (t Result) (t Expr), result ~ Result, x ~ t Expr) =>
254− ToExprs x (t result)
255− where
256− fromResult = fromColumns
257− toResult = toColumns
258−
259−
260−instance (KnownSpec spec, x ~ Col Expr spec) =>
261− ToExprs x (Col Result spec)
262− where
263− fromResult = fromColumns
264− toResult = toColumns
265−
266−
267−type FromExprs :: Type -> Type
268−type family FromExprs a
269−type instance FromExprs (Expr a) = a
270−type instance FromExprs (Col Expr spec) = Col Result spec
271−type instance FromExprs (EitherTable a b) = Either (FromExprs a) (FromExprs b)
272−type instance FromExprs (ListTable a) = [FromExprs a]
273−type instance FromExprs (MaybeTable a) = Maybe (FromExprs a)
274−type instance FromExprs (NonEmptyTable a) = NonEmpty (FromExprs a)
275−type instance FromExprs (TheseTable a b) = These (FromExprs a) (FromExprs b)
276−type instance FromExprs (a, b) = (FromExprs a, FromExprs b)
277−type instance FromExprs (a, b, c) = (FromExprs a, FromExprs b, FromExprs c)
278−type instance FromExprs (a, b, c, d) =
279− (FromExprs a, FromExprs b, FromExprs c, FromExprs d)
280−type instance FromExprs (a, b, c, d, e) =
281− (FromExprs a, FromExprs b, FromExprs c, FromExprs d, FromExprs e)
282−type instance FromExprs (a, b, c, d, e, f) =
283− ( FromExprs a, FromExprs b, FromExprs c, FromExprs d, FromExprs e
284− , FromExprs f
285− )
286−type instance FromExprs (a, b, c, d, e, f, g) =
287− ( FromExprs a, FromExprs b, FromExprs c, FromExprs d, FromExprs e
288− , FromExprs f, FromExprs g
289− )
290−type instance FromExprs (t Expr) = t Result
291−type instance FromExprs (t (Col Expr)) = t (Col Result)
292−
293−
294119-- | @Serializable@ witnesses the one-to-one correspondence between the type
295120-- @sql@, which contains SQL expressions, and the type @haskell@, which
296121-- contains the Haskell decoding of rows containing @sql@ SQL expressions.
@@ -303,68 +128,21 @@ instance {-# OVERLAPPING #-} Sql DBType a => Serializable (Expr a) a
303128-- | Use @lit@ to turn literal Haskell values into expressions. @lit@ is
304129-- capable of lifting single @Expr@s to full tables.
305130lit :: forall exprs a. Serializable exprs a => a -> exprs
306−lit = fromColumns . litHTable . toResult @exprs
131+lit = fromColumns . litHTable . toResult @_ @exprs
307132
308133
309134parse :: forall exprs a. Serializable exprs a => Hasql.Row a
310−parse = fromResult @exprs <$> parseHTable
311−
312−
313−type Encodes :: Type -> Type -> Constraint
314−class Serializable exprs a => Encodes a exprs | a -> exprs, exprs -> a
315−
316−
317−instance KnownSpec spec => Encodes (Col Result spec) (Col Expr spec)
318−
319−
320−instance Serializable (t Result) (t Expr) => Encodes (t Expr) (t Result)
321−
322−
323−instance HTable t => Encodes (t (Col Result)) (t (Col Expr))
324−
325−
326−instance (Encodes a x, Encodes b y) => Encodes (Either a b) (EitherTable x y)
327−
328−
329−instance Encodes a x => Encodes [a] (ListTable x)
330−
331−
332−instance Encodes a x => Encodes (Maybe a) (MaybeTable x)
333−
334−
335−instance Encodes a x => Encodes (NonEmpty a) (NonEmptyTable x)
336−
337−
338−instance (Encodes a x, Encodes b y) => Encodes (These a b) (TheseTable x y)
339−
340−
341−instance (Encodes a x, Encodes b y) => Encodes (a, b) (x, y)
342−
343−
344−instance (Encodes a x, Encodes b y, Encodes c z) =>
345− Encodes (a, b, c) (x, y, z)
346−
347−
348−instance (Encodes a w, Encodes b x, Encodes c y, Encodes d z) =>
349− Encodes (a, b, c, d) (w, x, y, z)
350−
351−
352−instance (Encodes a v, Encodes b w, Encodes c x, Encodes d y, Encodes e z) =>
353− Encodes (a, b, c, d, e) (v, w, x, y, z)
354−
355−
356−litTable :: Encodes a exprs => a -> exprs
357−litTable = lit
135+parse = fromResult @_ @exprs <$> parseHTable
358136
359137
360−litHTable :: HTable t => t (Col Result) -> t (Col Expr)
138+litHTable :: HTable t => t Result -> t Expr
361139litHTable as = htabulate $ \field ->
362140 case hfield hspecs field of
363− SSpec {nullity, info} -> case hfield as field of
364− Result value -> DB (slitExpr nullity info value)
141+ Spec {nullity, info} -> case hfield as field of
142+ Identity value -> slitExpr nullity info value
365143
366144
367−parseHTable :: HTable t => Hasql.Row (t (Col Result))
145+parseHTable :: HTable t => Hasql.Row (t Result)
368146parseHTable = unwrapApplicative $ htabulateA $ \field ->
369147 WrapApplicative $ case hfield hspecs field of
370− SSpec {nullity, info} -> Result <$> sparseValue nullity info
148+ Spec {nullity, info} -> Identity <$> sparseValue nullity info
src/Rel8/Table/Tag.hsdeleted−97
@@ -1,97 +0,0 @@
1−{-# language DataKinds #-}
2−{-# language FlexibleInstances #-}
3−{-# language GADTs #-}
4−{-# language InstanceSigs #-}
5−{-# language NamedFieldPuns #-}
6−{-# language ScopedTypeVariables #-}
7−{-# language StandaloneKindSignatures #-}
8−{-# language TypeApplications #-}
9−{-# language UndecidableInstances #-}
10−
11−module Rel8.Table.Tag
12− ( Tag(..), Taggable
13− , fromAggregate
14− , fromExpr
15− , fromName
16− )
17−where
18−
19−-- base
20−import Control.Applicative ( (<|>), empty )
21−import Data.Kind ( Constraint, Type )
22−import Data.Foldable ( fold )
23−import Data.Monoid ( getFirst )
24−import Data.Proxy ( Proxy( Proxy ) )
25−import GHC.TypeLits ( KnownSymbol, Symbol, symbolVal )
26−import Prelude
27−
28−-- rel8
29−import Rel8.Aggregate ( Aggregate, Aggregator, foldInputs )
30−import Rel8.Expr ( Expr )
31−import Rel8.Expr.Opaleye ( fromPrimExpr )
32−import Rel8.Schema.Name ( Name( Name ) )
33−import Rel8.Schema.Null ( Sql )
34−import Rel8.Type.Monoid ( DBMonoid )
35−
36−
37−type Tag :: Symbol -> Type -> Type
38−data Tag label a = Tag
39− { expr :: Expr a
40− , aggregator :: Maybe Aggregator
41− , name :: Name a
42− }
43−
44−
45−type Taggable :: Type -> Constraint
46−class Taggable a where
47− tappend :: KnownSymbol label => Tag label a -> Tag label a -> Tag label a
48− tempty :: KnownSymbol label => Tag label a
49−
50−
51−instance Sql DBMonoid a => Taggable a where
52− tappend :: forall label. KnownSymbol label
53− => Tag label a -> Tag label a -> Tag label a
54− tappend a b = Tag
55− { expr = expr a <> expr b
56− , aggregator = aggregator a <|> aggregator b
57− , name = case (name a, symbolVal (Proxy @label)) of
58− (Name x, y)
59− | x == y -> name b
60− | otherwise -> name a
61− }
62− {-# INLINABLE tappend #-}
63−
64− tempty :: forall label. KnownSymbol label => Tag label a
65− tempty = Tag
66− { expr = mempty
67− , aggregator = empty
68− , name = Name (symbolVal (Proxy @label))
69− }
70− {-# INLINABLE tempty #-}
71−
72−
73−instance (KnownSymbol label, Taggable a) => Semigroup (Tag label a) where
74− (<>) = tappend
75−
76−
77−instance (KnownSymbol label, Taggable a) => Monoid (Tag label a) where
78− mempty = tempty
79−
80−
81−fromAggregate :: forall a label. (KnownSymbol label, Taggable a)
82− => Aggregate (Expr a) -> Tag label a
83−fromAggregate = fold . getFirst . foldInputs go
84− where
85− go aggregator primExpr = pure $ (tempty @a @label)
86− { expr = fromPrimExpr primExpr
87− , aggregator
88− }
89−
90−
91−fromExpr :: forall label a. (KnownSymbol label, Taggable a)
92− => Expr a -> Tag label a
93−fromExpr expr = (tempty @a @label) {expr}
94−
95−
96−fromName :: forall a label. Taggable a => Name a -> Tag label a
97−fromName name = (tempty @a @"") {name}
src/Rel8/Table/These.hs+212−141
@@ -5,7 +5,6 @@
55{-# language FlexibleInstances #-}
66{-# language MultiParamTypeClasses #-}
77{-# language NamedFieldPuns #-}
8−{-# language RecordWildCards #-}
98{-# language ScopedTypeVariables #-}
109{-# language StandaloneKindSignatures #-}
1110{-# language TupleSections #-}
@@ -13,88 +12,115 @@
1312{-# language TypeFamilies #-}
1413{-# language UndecidableInstances #-}
1514
15+{-# options_ghc -fno-warn-orphans #-}
16+
1617module Rel8.Table.These
1718 ( TheseTable(..)
1819 , theseTable, thisTable, thatTable, thoseTable
1920 , isThisTable, isThatTable, isThoseTable
2021 , hasHereTable, hasThereTable
2122 , justHereTable, justThereTable
22− , aggregateTheseTable, nameTheseTable
23+ , alignMaybeTable
24+ , aggregateTheseTable
25+ , nameTheseTable
2326 )
2427where
2528
2629-- base
2730import Data.Bifunctor ( Bifunctor, bimap )
28−import Data.Functor.Identity ( runIdentity )
2931import Data.Kind ( Type )
30−import Prelude hiding ( undefined )
32+import Data.Maybe ( isJust )
33+import Prelude hiding ( null, undefined )
3134
3235-- rel8
3336import Rel8.Aggregate ( Aggregate )
3437import Rel8.Expr ( Expr )
35−import Rel8.Expr.Bool ( (&&.), not_ )
36−import Rel8.Expr.Null ( isNonNull )
37−import Rel8.Schema.Context.Label
38− ( Labelable
39− , HLabelable, hlabeler, hunlabeler
40− )
41−import Rel8.Schema.Context.Nullify
42− ( Nullifiable, ConstrainTag
43− , HNullifiable, HConstrainTag
44− , hencodeTag, hdecodeTag
45− , hnullifier, hunnullifier
46− )
47−import Rel8.Schema.HTable ( HTable )
48−import Rel8.Schema.HTable.Label ( hlabel, hunlabel )
38+import Rel8.Expr.Bool ( (&&.), (||.), boolExpr, not_ )
39+import Rel8.Expr.Null ( null, isNonNull )
40+import Rel8.Kind.Context ( Reifiable )
41+import Rel8.Schema.Context.Nullify ( Nullifiable )
42+import Rel8.Schema.Dict ( Dict( Dict ) )
43+import Rel8.Schema.HTable.Label ( hlabel, hrelabel, hunlabel )
4944import Rel8.Schema.HTable.Identity ( HIdentity(..) )
50−import Rel8.Schema.HTable.Nullify ( hnullify, hunnullify )
45+import Rel8.Schema.HTable.Maybe ( HMaybeTable(..) )
5146import Rel8.Schema.HTable.These ( HTheseTable(..) )
52−import Rel8.Schema.Name ( Name )
53−import Rel8.Table ( Table, Columns, Context, fromColumns, toColumns )
47+import qualified Rel8.Schema.Kind as K
48+import Rel8.Schema.Name ( Name )
49+import Rel8.Table
50+ ( Table, Columns, Context, fromColumns, toColumns
51+ , FromExprs, fromResult, toResult
52+ , Transpose
53+ )
5454import Rel8.Table.Eq ( EqTable, eqTable )
5555import Rel8.Table.Maybe
5656 ( MaybeTable(..)
5757 , maybeTable, justTable, nothingTable
5858 , isJustTable
59− , aggregateMaybeTable, nameMaybeTable
59+ , aggregateMaybeTable
60+ , nameMaybeTable
6061 )
62+import Rel8.Table.Nullify ( Nullify, guard )
6163import Rel8.Table.Ord ( OrdTable, ordTable )
62−import Rel8.Table.Recontextualize ( Recontextualize )
63−import Rel8.Table.Tag ( Tag(..) )
64+import Rel8.Table.Projection ( Biprojectable, Projectable, biproject, project )
65+import Rel8.Table.Serialize ( ToExprs )
6466import Rel8.Table.Undefined ( undefined )
6567import Rel8.Type.Tag ( MaybeTag )
6668
6769-- semigroupoids
68−import Data.Functor.Apply ( Apply, (<.>), liftF2 )
70+import Data.Functor.Apply ( Apply, (<.>) )
6971import Data.Functor.Bind ( Bind, (>>-) )
7072
71−
72−type TheseTable :: Type -> Type -> Type
73−data TheseTable a b = TheseTable
74− { here :: MaybeTable a
75− , there :: MaybeTable b
73+-- these
74+import Data.These ( These( This, That, These ) )
75+import Data.These.Combinators ( justHere, justThere )
76+
77+
78+-- | @TheseTable a b@ is a Rel8 table that contains either the table @a@, the
79+-- table @b@, or both tables @a@ and @b@. You can construct @TheseTable@s using
80+-- 'thisTable', 'thatTable' and 'thoseTable'. @TheseTable@s can be
81+-- eliminated/pattern matched using 'theseTable'.
82+--
83+-- @TheseTable@ is operationally the same as Haskell's 'These' type, but
84+-- adapted to work with Rel8.
85+type TheseTable :: K.Context -> Type -> Type -> Type
86+data TheseTable context a b = TheseTable
87+ { here :: MaybeTable context a
88+ , there :: MaybeTable context b
7689 }
7790 deriving stock Functor
7891
7992
80−instance Bifunctor TheseTable where
93+instance Biprojectable (TheseTable context) where
94+ biproject f g (TheseTable a b) = TheseTable (project f a) (project g b)
95+
96+
97+instance Nullifiable context => Bifunctor (TheseTable context) where
8198 bimap f g (TheseTable a b) = TheseTable (fmap f a) (fmap g b)
8299
83100
84−instance (Table Expr a, Semigroup a) => Apply (TheseTable a) where
101+instance Projectable (TheseTable context a) where
102+ project f (TheseTable a b) = TheseTable a (project f b)
103+
104+
105+instance (context ~ Expr, Table Expr a, Semigroup a) =>
106+ Apply (TheseTable context a)
107+ where
85108 fs <.> as = TheseTable
86109 { here = here fs <> here as
87110 , there = there fs <.> there as
88111 }
89112
90113
91−instance (Table Expr a, Semigroup a) => Applicative (TheseTable a)
114+instance (context ~ Expr, Table Expr a, Semigroup a) =>
115+ Applicative (TheseTable context a)
92116 where
93117 pure = thatTable
94118 (<*>) = (<.>)
95119
96120
97−instance (Table Expr a, Semigroup a) => Bind (TheseTable a) where
121+instance (context ~ Expr, Table Expr a, Semigroup a) =>
122+ Bind (TheseTable context a)
123+ where
98124 TheseTable here1 ma >>- f = case ma >>- f' of
99125 mtb -> TheseTable
100126 { here = maybeTable here1 ((here1 <>) . fst) mtb
@@ -105,12 +131,14 @@ instance (Table Expr a, Semigroup a) => Bind (TheseTable a) where
105131 TheseTable here2 mb -> (here2,) <$> mb
106132
107133
108−instance (Table Expr a, Semigroup a) => Monad (TheseTable a) where
134+instance (context ~ Expr, Table Expr a, Semigroup a) =>
135+ Monad (TheseTable context a)
136+ where
109137 (>>=) = (>>-)
110138
111139
112−instance (Table Expr a, Table Expr b, Semigroup a, Semigroup b) =>
113− Semigroup (TheseTable a b)
140+instance (context ~ Expr, Table Expr a, Table Expr b, Semigroup a, Semigroup b) =>
141+ Semigroup (TheseTable context a b)
114142 where
115143 a <> b = TheseTable
116144 { here = here a <> here b
@@ -120,83 +148,175 @@ instance (Table Expr a, Table Expr b, Semigroup a, Semigroup b) =>
120148
121149instance
122150 ( Table context a, Table context b
123− , Labelable context, Nullifiable context, ConstrainTag context MaybeTag
124− ) => Table context (TheseTable a b)
151+ , Reifiable context, context ~ context'
152+ )
153+ => Table context' (TheseTable context a b)
125154 where
126− type Columns (TheseTable a b) = HTheseTable (Columns a) (Columns b)
127− type Context (TheseTable a b) = Context a
128−
129− toColumns = toColumns2 toColumns toColumns
130− fromColumns = fromColumns2 fromColumns fromColumns
131−
132−
133−instance
134− ( Labelable from, Nullifiable from, ConstrainTag from MaybeTag
135− , Labelable to, Nullifiable to, ConstrainTag to MaybeTag
136− , Recontextualize from to a1 b1
137− , Recontextualize from to a2 b2
138− ) =>
139− Recontextualize from to (TheseTable a1 a2) (TheseTable b1 b2)
140−
141−
142−instance (EqTable a, EqTable b) => EqTable (TheseTable a b) where
143− eqTable = toColumns2 id id (thoseTable (eqTable @a) (eqTable @b))
155+ type Columns (TheseTable context a b) = HTheseTable (Columns a) (Columns b)
156+ type Context (TheseTable context a b) = Context a
157+ type FromExprs (TheseTable context a b) =
158+ These (FromExprs a) (FromExprs b)
159+ type Transpose to (TheseTable context a b) =
160+ TheseTable to (Transpose to a) (Transpose to b)
161+
162+ toColumns TheseTable {here, there} = HTheseTable
163+ { hhereTag = hlabel $ HIdentity $ tag here
164+ , hhere =
165+ hlabel $ guard (tag here) isJust isNonNull $ toColumns $ just here
166+ , hthereTag = hlabel $ HIdentity $ tag there
167+ , hthere =
168+ hlabel $ guard (tag there) isJust isNonNull $ toColumns $ just there
169+ }
144170
171+ fromColumns HTheseTable {hhereTag, hhere, hthereTag, hthere} = TheseTable
172+ { here = MaybeTable
173+ { tag = unHIdentity $ hunlabel hhereTag
174+ , just = fromColumns $ hunlabel hhere
175+ }
176+ , there = MaybeTable
177+ { tag = unHIdentity $ hunlabel hthereTag
178+ , just = fromColumns $ hunlabel hthere
179+ }
180+ }
145181
146−instance (OrdTable a, OrdTable b) => OrdTable (TheseTable a b) where
147− ordTable = toColumns2 id id (thoseTable (ordTable @a) (ordTable @b))
182+ toResult tables = HTheseTable
183+ { hhereTag = hrelabel hhereTag
184+ , hhere = hrelabel hhere
185+ , hthereTag = hrelabel hthereTag
186+ , hthere = hrelabel hthere
187+ }
188+ where
189+ HMaybeTable
190+ { htag = hhereTag
191+ , hjust = hhere
192+ } = toResult @_ @(MaybeTable context a) (justHere tables)
193+ HMaybeTable
194+ { htag = hthereTag
195+ , hjust = hthere
196+ } = toResult @_ @(MaybeTable context b) (justThere tables)
197+
198+ fromResult HTheseTable {hhereTag, hhere, hthereTag, hthere} =
199+ case (here, there) of
200+ (Just a, Nothing) -> This a
201+ (Nothing, Just b) -> That b
202+ (Just a, Just b) -> These a b
203+ _ -> error "These.fromColumns: mismatch between tags and data"
204+ where
205+ here = fromResult @_ @(MaybeTable context a) mhere
206+ there = fromResult @_ @(MaybeTable context b) mthere
207+ mhere = HMaybeTable
208+ { htag = hrelabel hhereTag
209+ , hjust = hrelabel hhere
210+ }
211+ mthere = HMaybeTable
212+ { htag = hrelabel hthereTag
213+ , hjust = hrelabel hthere
214+ }
215+
216+
217+instance (EqTable a, EqTable b, context ~ Expr) =>
218+ EqTable (TheseTable context a b)
219+ where
220+ eqTable = HTheseTable
221+ { hhereTag = hlabel (HIdentity Dict)
222+ , hhere = hlabel (eqTable @(Nullify context a))
223+ , hthereTag = hlabel (HIdentity Dict)
224+ , hthere = hlabel (eqTable @(Nullify context b))
225+ }
148226
149227
150−toHereTag :: Tag "isJust" a -> Tag "hasHere" a
151−toHereTag Tag {..} = Tag {..}
228+instance (OrdTable a, OrdTable b, context ~ Expr) =>
229+ OrdTable (TheseTable context a b)
230+ where
231+ ordTable = HTheseTable
232+ { hhereTag = hlabel (HIdentity Dict)
233+ , hhere = hlabel (ordTable @(Nullify context a))
234+ , hthereTag = hlabel (HIdentity Dict)
235+ , hthere = hlabel (ordTable @(Nullify context b))
236+ }
152237
153238
154−toThereTag :: Tag "isJust" a -> Tag "hasThere" a
155−toThereTag Tag {..} = Tag {..}
239+instance (ToExprs exprs1 a, ToExprs exprs2 b, x ~ TheseTable Expr exprs1 exprs2) =>
240+ ToExprs x (These a b)
156241
157242
158−isThisTable :: TheseTable a b -> Expr Bool
243+-- | Test if a 'TheseTable' was constructed with 'thisTable'.
244+--
245+-- Corresponds to 'Data.These.Combinators.isThis'.
246+isThisTable :: TheseTable Expr a b -> Expr Bool
159247isThisTable a = hasHereTable a &&. not_ (hasThereTable a)
160248
161249
162−isThatTable :: TheseTable a b -> Expr Bool
250+-- | Test if a 'TheseTable' was constructed with 'thatTable'.
251+--
252+-- Corresponds to 'Data.These.Combinators.isThat'.
253+isThatTable :: TheseTable Expr a b -> Expr Bool
163254isThatTable a = not_ (hasHereTable a) &&. hasThereTable a
164255
165256
166−isThoseTable :: TheseTable a b -> Expr Bool
257+-- | Test if a 'TheseTable' was constructed with 'thoseTable'.
258+--
259+-- Corresponds to 'Data.These.Combinators.isThese'.
260+isThoseTable :: TheseTable Expr a b -> Expr Bool
167261isThoseTable a = hasHereTable a &&. hasThereTable a
168262
169263
170−hasHereTable :: TheseTable a b -> Expr Bool
264+-- | Test if the @a@ side of @TheseTable a b@ is present.
265+--
266+-- Corresponds to 'Data.These.Combinators.hasHere'.
267+hasHereTable :: TheseTable Expr a b -> Expr Bool
171268hasHereTable TheseTable {here} = isJustTable here
172269
173270
174−hasThereTable :: TheseTable a b -> Expr Bool
271+-- | Test if the @b@ table of @TheseTable a b@ is present.
272+--
273+-- Corresponds to 'Data.These.Combinators.hasThere'.
274+hasThereTable :: TheseTable Expr a b -> Expr Bool
175275hasThereTable TheseTable {there} = isJustTable there
176276
177277
178−justHereTable :: TheseTable a b -> MaybeTable a
278+-- | Attempt to project out the @a@ table of a @TheseTable a b@.
279+--
280+-- Corresponds to 'Data.These.Combinators.justHere'.
281+justHereTable :: TheseTable context a b -> MaybeTable context a
179282justHereTable = here
180283
181284
182−justThereTable :: TheseTable a b -> MaybeTable b
285+-- | Attempt to project out the @b@ table of a @TheseTable a b@.
286+--
287+-- Corresponds to 'Data.These.Combinators.justThere'.
288+justThereTable :: TheseTable context a b -> MaybeTable context b
183289justThereTable = there
184290
185291
186−thisTable :: Table Expr b => a -> TheseTable a b
292+-- | Construct a @TheseTable@ from two 'MaybeTable's.
293+alignMaybeTable :: ()
294+ => MaybeTable Expr a
295+ -> MaybeTable Expr b
296+ -> MaybeTable Expr (TheseTable Expr a b)
297+alignMaybeTable a b = MaybeTable tag (pure (TheseTable a b))
298+ where
299+ tag = boolExpr null mempty (isJustTable a ||. isJustTable b)
300+
301+
302+-- | Construct a @TheseTable@. Corresponds to 'This'.
303+thisTable :: Table Expr b => a -> TheseTable Expr a b
187304thisTable a = TheseTable (justTable a) nothingTable
188305
189306
190−thatTable :: Table Expr a => b -> TheseTable a b
307+-- | Construct a @TheseTable@. Corresponds to 'That'.
308+thatTable :: Table Expr a => b -> TheseTable Expr a b
191309thatTable b = TheseTable nothingTable (justTable b)
192310
193311
194−thoseTable :: a -> b -> TheseTable a b
312+-- | Construct a @TheseTable@. Corresponds to 'These'.
313+thoseTable :: a -> b -> TheseTable Expr a b
195314thoseTable a b = TheseTable (justTable a) (justTable b)
196315
197316
317+-- | Pattern match on a 'TheseTable'. Corresponds to 'these'.
198318theseTable :: Table Expr c
199− => (a -> c) -> (b -> c) -> (a -> b -> c) -> TheseTable a b -> c
319+ => (a -> c) -> (b -> c) -> (a -> b -> c) -> TheseTable Expr a b -> c
200320theseTable f g h TheseTable {here, there} =
201321 maybeTable
202322 (maybeTable undefined f here)
@@ -204,83 +324,34 @@ theseTable f g h TheseTable {here, there} =
204324 there
205325
206326
327+-- | Lift a pair of aggregating functions to operate on an 'TheseTable'.
328+-- @thisTable@s, @thatTable@s and @thoseTable@s are grouped separately.
207329aggregateTheseTable :: ()
208− => (a -> Aggregate c)
209− -> (b -> Aggregate d)
210− -> TheseTable a b
211− -> Aggregate (TheseTable c d)
212−aggregateTheseTable f g TheseTable {here, there} =
213− liftF2 TheseTable (aggregateMaybeTable f here) (aggregateMaybeTable g there)
330+ => (exprs -> aggregates)
331+ -> (exprs' -> aggregates')
332+ -> TheseTable Expr exprs exprs'
333+ -> TheseTable Aggregate aggregates aggregates'
334+aggregateTheseTable f g (TheseTable here there) = TheseTable
335+ { here = aggregateMaybeTable f here
336+ , there = aggregateMaybeTable g there
337+ }
214338
215339
340+-- | Construct a 'TheseTable' in the 'Name' context. This can be useful if you
341+-- have a 'TheseTable' that you are storing in a table and need to construct a
342+-- 'TableSchema'.
216343nameTheseTable :: ()
217344 => Name (Maybe MaybeTag)
345+ -- ^ The name of the column to track the presence of the @a@ table.
218346 -> Name (Maybe MaybeTag)
347+ -- ^ The name of the column to track the presence of the @b@ table.
219348 -> a
349+ -- ^ Names of the columns in the @a@ table.
220350 -> b
221− -> TheseTable a b
351+ -- ^ Names of the columns in the @b@ table.
352+ -> TheseTable Name a b
222353nameTheseTable here there a b =
223354 TheseTable
224355 { here = nameMaybeTable here a
225356 , there = nameMaybeTable there b
226357 }
227−
228−
229−toColumns2 ::
230− ( HTable t
231− , HTable u
232− , HConstrainTag context MaybeTag
233− , HLabelable context
234− , HNullifiable context
235− )
236− => (a -> t context)
237− -> (b -> u context)
238− -> TheseTable a b
239− -> HTheseTable t u context
240−toColumns2 f g TheseTable {here, there} = HTheseTable
241− { hhereTag = HIdentity $ hencodeTag (toHereTag (tag here))
242− , hhere =
243− hlabel hlabeler $ hnullify (hnullifier (tag here) isNonNull) $ f (just here)
244− , hthereTag = HIdentity $ hencodeTag (toThereTag (tag there))
245− , hthere =
246− hlabel hlabeler $ hnullify (hnullifier (tag there) isNonNull) $ g (just there)
247− }
248−
249−
250−fromColumns2 ::
251− ( HTable t
252− , HTable u
253− , HConstrainTag context MaybeTag
254− , HLabelable context
255− , HNullifiable context
256− )
257− => (t context -> a)
258− -> (u context -> b)
259− -> HTheseTable t u context
260− -> TheseTable a b
261−fromColumns2 f g HTheseTable {hhereTag, hhere, hthereTag, hthere} = TheseTable
262− { here =
263− let
264− tag = hdecodeTag $ unHIdentity hhereTag
265− in
266− MaybeTable
267− { tag
268− , just = f $
269− runIdentity $
270− hunnullify (\a -> pure . hunnullifier a) $
271− hunlabel hunlabeler
272− hhere
273− }
274− , there =
275− let
276− tag = hdecodeTag $ unHIdentity hthereTag
277− in
278− MaybeTable
279− { tag
280− , just = g $
281− runIdentity $
282− hunnullify (\a -> pure . hunnullifier a) $
283− hunlabel hunlabeler
284− hthere
285− }
286− }
src/Rel8/Table/Transpose.hsnew file+46
@@ -0,0 +1,46 @@
1+{-# language DataKinds #-}
2+{-# language FlexibleInstances #-}
3+{-# language FunctionalDependencies #-}
4+{-# language StandaloneKindSignatures #-}
5+{-# language TypeFamilies #-}
6+{-# language UndecidableInstances #-}
7+
8+module Rel8.Table.Transpose
9+ ( Transposes
10+ )
11+where
12+
13+-- base
14+import Data.Kind ( Constraint, Type )
15+import Prelude ()
16+
17+-- rel8
18+import qualified Rel8.Schema.Kind as K
19+import Rel8.Table ( Table, Transpose, Congruent )
20+
21+
22+-- | @'Transposes' from to a b@ means that @a@ and @b@ are 'Table's, in the
23+-- @from@ and @to@ contexts respectively, which share the same underlying
24+-- structure. In other words, @b@ is a version of @a@ transposed from the
25+-- @from@ context to the @to@ context (and vice versa).
26+type Transposes :: K.Context -> K.Context -> Type -> Type -> Constraint
27+class
28+ ( Table from a
29+ , Table to b
30+ , Congruent a b
31+ , b ~ Transpose to a
32+ , a ~ Transpose from b
33+ )
34+ => Transposes from to a b
35+ | a -> from
36+ , b -> to
37+ , a to -> b
38+ , b from -> a
39+instance
40+ ( Table from a
41+ , Table to b
42+ , Congruent a b
43+ , b ~ Transpose to a
44+ , a ~ Transpose from b
45+ )
46+ => Transposes from to a b
src/Rel8/Table/Undefined.hs+5−5
@@ -11,16 +11,16 @@ where
1111import Prelude hiding ( undefined )
1212
1313-- rel8
14−import Rel8.Expr ( Expr, Col(..) )
14+import Rel8.Expr ( Expr )
1515import Rel8.Expr.Null ( snull, unsafeUnnullify )
1616import Rel8.Schema.HTable ( htabulate, hfield, hspecs )
1717import Rel8.Schema.Null ( Nullity( Null, NotNull ) )
18−import Rel8.Schema.Spec ( SSpec(..) )
18+import Rel8.Schema.Spec ( Spec(..) )
1919import Rel8.Table ( Table, fromColumns )
2020
2121
2222undefined :: Table Expr a => a
2323undefined = fromColumns $ htabulate $ \field -> case hfield hspecs field of
24− SSpec {nullity, info} -> case nullity of
25− Null -> DB (snull info)
26− NotNull -> DB (unsafeUnnullify (snull info))
24+ Spec {nullity, info} -> case nullity of
25+ Null -> snull info
26+ NotNull -> unsafeUnnullify (snull info)
src/Rel8/Table/Window.hsnew file+43
@@ -0,0 +1,43 @@
1+{-# language MonoLocalBinds #-}
2+
3+module Rel8.Table.Window
4+ ( cumulative
5+ , cumulative_
6+ , currentRow
7+ )
8+where
9+
10+-- base
11+import Prelude
12+
13+-- opaleye
14+import qualified Opaleye.Window as Opaleye
15+
16+-- rel8
17+import Rel8.Aggregate ( Aggregates )
18+import qualified Rel8.Expr.Window as Expr
19+import Rel8.Schema.HTable ( hfield, htabulateA )
20+import Rel8.Table ( fromColumns, toColumns )
21+import Rel8.Window ( Window( Window ) )
22+
23+
24+-- | 'cumulative' allows the use of aggregation functions in 'Window'
25+-- expressions. In particular, @'cumulative' 'Rel8.sum'@
26+-- (when combined with 'Rel8.Window.orderPartitionBy') gives a running total,
27+-- also known as a \"cumulative sum\", hence the name @cumulative@.
28+cumulative :: Aggregates aggregates exprs => (a -> aggregates) -> Window a exprs
29+cumulative f =
30+ fmap fromColumns $
31+ htabulateA $ \field ->
32+ Expr.cumulative ((`hfield` field) . toColumns . f)
33+
34+
35+-- | A version of 'cumulative' for use with nullary aggregators like
36+-- 'Rel8.Expr.Aggregate.countStar'.
37+cumulative_ :: Aggregates aggregates exprs => aggregates -> Window a exprs
38+cumulative_ = cumulative . const
39+
40+
41+-- | Return every column of the current row of a window query.
42+currentRow :: Window a a
43+currentRow = Window $ Opaleye.over (Opaleye.noWindowFunction id) mempty mempty
src/Rel8/Tabulate.hs+530−228
@@ -1,338 +1,640 @@
1−{-# language DeriveFunctor #-}
2−{-# language DerivingStrategies #-}
31{-# language FlexibleContexts #-}
2+{-# language MonoLocalBinds #-}
3+{-# language ScopedTypeVariables #-}
4+{-# language StandaloneKindSignatures #-}
5+{-# language TypeApplications #-}
46{-# language TupleSections #-}
7+{-# language UndecidableInstances #-}
8+
9+-- | "Rel8.Tabulate" provides an alternative API ('Tabulation') for writing
10+-- queries that complements the main "Rel8" API ('Query').
511
612module Rel8.Tabulate
7− ( Tabulation
8− , runTabulation
9− , tabulate
10− , tabulateA
13+ (
14+ Tabulation
15+
16+ -- * Interfacing with 'Query's
1117 , fromQuery
18+ , toQuery
1219 , liftQuery
13− , prebind
14− , postbind
15− , indexed
16− , ifilter
20+ , through
1721 , lookup
22+
23+ -- * Aggregation and Ordering
24+ , aggregate
25+ , distinct
26+ , order
27+
28+ -- ** Magic 'Tabulation's
29+ -- $magic
30+ , count
31+ , optional
32+ , many
33+ , some
34+ , exists
35+ , present
36+ , absent
37+
38+ -- * Natural joins
1839 , align
1940 , alignWith
2041 , leftAlign
2142 , leftAlignWith
43+ , rightAlign
44+ , rightAlignWith
2245 , zip
2346 , zipWith
2447 , similarity
2548 , difference
26− , aggregateTabulation
27− , optionalTabulation
2849 )
2950where
3051
3152-- base
32−import Control.Applicative ( liftA2 )
33−import Control.Monad ( join, liftM2 )
34−import Data.Bifunctor ( bimap, first )
53+import Control.Applicative ( (<|>), empty, liftA2 )
54+import Control.Monad ( liftM2 )
55+import Data.Bifunctor ( Bifunctor, bimap, first, second )
3556import Data.Foldable ( traverse_ )
36−import Data.Maybe ( fromMaybe )
37−import Prelude hiding ( filter, lookup, undefined, zip, zipWith )
57+import Data.Function ( on )
58+import Data.Functor.Contravariant ( Contravariant, (>$<), contramap )
59+import Data.Int ( Int64 )
60+import Data.Kind ( Type )
61+import Data.Maybe ( fromJust, fromMaybe )
62+import Prelude hiding ( lookup, zip, zipWith )
63+
64+-- bifunctors
65+import Data.Bifunctor.Clown ( Clown( Clown ), runClown )
66+
67+-- comonad
68+import Control.Comonad ( extract )
69+
70+-- opaleye
71+import qualified Opaleye.Aggregate as Opaleye
72+import qualified Opaleye.Order as Opaleye ( orderBy, distinctOnExplicit )
73+
74+-- profunctors
75+import Data.Profunctor ( dimap, lmap )
76+
77+-- product-profunctors
78+import Data.Profunctor.Product
79+ ( ProductProfunctor, (***!)
80+ , SumProfunctor, (+++!)
81+ )
82+import qualified Data.Profunctor.Product as PP
3883
3984-- rel8
40−import Rel8.Aggregate ( Aggregate )
85+import Rel8.Aggregate ( Aggregates )
4186import Rel8.Expr ( Expr )
42−import Rel8.Expr.Bool ( not_, true )
87+import Rel8.Expr.Aggregate ( countStar )
88+import Rel8.Expr.Bool ( true )
89+import Rel8.Order ( Order( Order ) )
4390import Rel8.Query ( Query )
44−import Rel8.Query.Aggregate ( aggregate )
45−import Rel8.Query.Exists ( withBy, withoutBy )
46−import Rel8.Query.Filter ( filter, where_ )
47−import Rel8.Query.Maybe ( optional )
91+import qualified Rel8.Query.Exists as Q ( exists, present, absent )
92+import Rel8.Query.Filter ( where_ )
93+import Rel8.Query.List ( catNonEmptyTable )
94+import qualified Rel8.Query.Maybe as Q ( optional )
95+import Rel8.Query.Opaleye ( mapOpaleye, unsafePeekQuery )
96+import Rel8.Query.Rebind ( rebind )
4897import Rel8.Query.These ( alignBy )
49−import Rel8.Table ( Table )
50−import Rel8.Table.Aggregate ( groupBy )
51−import Rel8.Table.Eq ( EqTable, (==:) )
52−import Rel8.Table.Maybe ( MaybeTable )
53−import Rel8.Table.These ( TheseTable, theseTable )
54−import Rel8.Table.Undefined ( undefined )
98+import Rel8.Table ( Table, fromColumns, toColumns )
99+import Rel8.Table.Aggregate ( hgroupBy, listAgg, nonEmptyAgg )
100+import Rel8.Table.Alternative
101+ ( AltTable, (<|>:)
102+ , AlternativeTable, emptyTable
103+ )
104+import Rel8.Table.Cols ( fromCols, toCols )
105+import Rel8.Table.Eq ( EqTable, (==:), eqTable )
106+import Rel8.Table.List ( ListTable( ListTable ) )
107+import Rel8.Table.Maybe ( MaybeTable( MaybeTable ), maybeTable )
108+import Rel8.Table.NonEmpty ( NonEmptyTable( NonEmptyTable ) )
109+import Rel8.Table.Opaleye ( aggregator, unpackspec )
110+import Rel8.Table.Ord ( OrdTable )
111+import Rel8.Table.Order ( ascTable )
112+import Rel8.Table.Projection
113+ ( Biprojectable, biproject
114+ , Projectable, project
115+ , apply
116+ )
117+import Rel8.Table.These ( TheseTable( TheseTable ), theseTable )
55118
56119-- semigroupoids
57120import Data.Functor.Apply ( Apply, liftF2 )
58−import Data.Functor.Bind ( Bind )
59−import qualified Data.Functor.Bind
60−import Data.Semigroup.Traversable.Class ( bitraverse1 )
121+import Data.Functor.Bind ( Bind, (>>-) )
122+
123+
124+type Key :: Type -> Type
125+type Key = Maybe
126+
127+
128+cat :: Table Expr k => Key k -> Query k
129+cat = maybe emptyTable pure
130+
131+
132+key :: (ProductProfunctor p, SumProfunctor p)
133+ => p a b -> p (Key a) (Key b)
134+key a = dimap from to (PP.empty +++! a)
135+ where
136+ from = maybe (Left ()) Right
137+ to = either (const Nothing) Just
138+
139+
140+keyed :: (ProductProfunctor p, SumProfunctor p)
141+ => p k l -> p a b -> p (Key k, a) (Key l, b)
142+keyed k a = key k ***! a
143+
144+
145+type Predicate :: Type -> Type
146+newtype Predicate a = Predicate (Maybe (a -> Expr Bool))
147+
148+
149+instance Contravariant Predicate where
150+ contramap f (Predicate a) = Predicate (lmap f <$> a)
151+
152+
153+instance Semigroup (Predicate k) where
154+ Predicate ma <> Predicate mb = Predicate $ ma <|> mb
155+
156+
157+instance Monoid (Predicate k) where
158+ mempty = Predicate Nothing
159+
160+
161+match :: EqTable k => Key k -> Predicate k
162+match = Predicate . fmap (==:)
163+
164+
165+ensure :: Predicate k -> Key k -> Query ()
166+ensure (Predicate mp) = traverse_ (\k -> traverse_ (\p -> where_ (p k)) mp)
61167
62168
63−-- | @'Tabulation' k a@ is denotionally a @MultiMap k a@ — a @Map@ where each
64−-- key @k@ corresponds to potentially multiple @a@ (i.e., @'Query' a@). This
65−-- @MultiMap@ supports 'lookup' and other operations you would expect it to.
169+-- | A @'Tabulation' k a@ is like a @'Query' a@, except that each row also
170+-- has a key @k@ in addition to the value @a@. 'Tabulation's can be composed
171+-- monadically just like 'Query's, but the resulting join is more like a
172+-- @NATURAL JOIN@ (based on the common key column(s) @k@) than the
173+-- @CROSS JOIN@ given by 'Query'.
66174--
67−-- \"Identity\" 'Tabulation's are created using 'tabulate'. 'Tabulation's can
68−-- be composed with 'Query's with 'prebind' or 'postbind' to form new
69−-- 'Tabulation's.
70−newtype Tabulation k a = Tabulation (k -> Query (Maybe k, a))
71− deriving stock Functor
175+-- Another way to think of @'Tabulation' k a@ is as analogous to @Map k a@ in
176+-- the same way @'Query' a@ is analogous to @[a]@. However, there's nothing
177+-- stopping a 'Tabulation' from containing multiple rows with the same key, so
178+-- technically @Map k (NonEmpty a)@ is more accurate.
179+--
180+-- 'Tabulation's can be created from 'Query's with 'fromQuery' and 'liftQuery'
181+-- and converted back to 'Query's with 'lookup' and 'toQuery' (though note the
182+-- caveats that come with the latter).
183+type Tabulation :: Type -> Type -> Type
184+newtype Tabulation k a = Tabulation (Predicate k -> Query (Key k, a))
185+
186+
187+instance Biprojectable Tabulation where
188+ biproject f g =
189+ bimap
190+ (fromColumns . apply f . toColumns)
191+ (fromColumns . apply g . toColumns)
192+
193+
194+instance Bifunctor Tabulation where
195+ bimap f g (Tabulation a) = Tabulation $ \p ->
196+ bimap (fmap f) g <$> a (f >$< p)
197+
198+
199+instance Functor (Tabulation k) where
200+ fmap = second
72201
73202
203+instance Projectable (Tabulation k) where
204+ project f = fmap (fromColumns . apply f . toColumns)
205+
206+
207+-- | If @'Tabulation' k a@ is @Map k (NonEmpty a)@, then @(<.>)@ is
208+-- @intersectionWith (liftA2 (<*>))@
74209instance EqTable k => Apply (Tabulation k) where
75210 liftF2 = liftA2
76211
77212
213+-- | @pure = 'liftQuery' . pure@
78214instance EqTable k => Applicative (Tabulation k) where
79215 pure = liftQuery . pure
80216 liftA2 = liftM2
81217
82218
83219instance EqTable k => Bind (Tabulation k) where
84− join = join
220+ Tabulation as >>- f = Tabulation $ \p -> do
221+ (k, a) <- as p
222+ case f a of
223+ Tabulation bs -> do
224+ let p' = match k
225+ (k', b) <- bs (p' <> p)
226+ ensure p' k'
227+ pure (k' <|> k, b)
85228
86229
87230instance EqTable k => Monad (Tabulation k) where
88− Tabulation as >>= f = Tabulation $ \i -> do
89− (mk, a) <- as i
90− case mk of
91− Nothing -> case f a of
92− Tabulation bs -> bs i
93− Just k -> case f a of
94− Tabulation bs -> do
95− (mk', b) <- bs k
96− case mk' of
97− Nothing -> pure (mk, b)
98− Just k' -> do
99− where_ $ k ==: k'
100− pure (mk', b)
101−
102−
103−-- | This "undoes" 'fromQuery'.
104−--
105−-- @
106−-- 'runTabulation' . 'fromQuery' = id
107−-- 'fromQuery' . 'runTabulation' = id
108−-- @
109−--
110−-- Note however that it produces nonsense when passed a 'Tabulation' that was
111−-- made with from 'liftQuery' or 'pure'. In such cases the returned 'Query'
112−-- will always produce zero rows.
113−runTabulation :: EqTable k => Tabulation k a -> Query (k, a)
114−runTabulation (Tabulation f) = do
115− (mk, a) <- f i
116− case mk of
117− Nothing -> do
118− -- Opaleye tries to be too clever optimising "WHERE FALSE" and generates
119− -- invalid SQL, so we use "WHERE NOT TRUE" instead
120− where_ $ not_ true
121− pure (i, a)
122− Just k -> pure (k, a)
123− where
124− i = undefined
231+ (>>=) = (>>-)
125232
126233
127−liftQuery :: Query a -> Tabulation k a
128−liftQuery query = Tabulation $ const $ fmap (Nothing,) query
234+-- | If @'Tabulation' k a@ is @Map k (NonEmpty a)@, then @(<|>:)@ is
235+-- @unionWith (<>)@.
236+instance EqTable k => AltTable (Tabulation k) where
237+ tas <|>: tbs = do
238+ eas <- peek tas
239+ ebs <- peek tbs
240+ case (eas, ebs) of
241+ (Left as, Left bs) -> liftQuery $ as <|>: bs
242+ (Right as, Right bs) -> fromQuery $ as <|>: bs
243+ _ -> catNonEmptyTable `through` ((<>) `on` some) tas tbs
244+
245+
246+instance EqTable k => AlternativeTable (Tabulation k) where
247+ emptyTable = Tabulation $ const $ fmap (empty,) emptyTable
248+
249+
250+-- | If @'Tabulation' k a@ is @Map k (NonEmpty a)@, then @(<>)@ is
251+-- @unionWith (liftA2 (<>))@.
252+instance (EqTable k, Table Expr a, Semigroup a) => Semigroup (Tabulation k a)
253+ where
254+ (<>) = alignWith (theseTable id id (<>))
255+
256+
257+instance (EqTable k, Table Expr a, Semigroup a) => Monoid (Tabulation k a)
258+ where
259+ mempty = emptyTable
129260
130261
131−-- | 'tabulate' creates an \"identity\" @'Tabulation' k a@ that allows @a@ be
132−-- indexed by one or more of its columns @k@. Some examples:
262+-- | Any 'Query' of key-value pairs @(k, a)@ can be a @'Tabulation' k a@.
263+fromQuery :: Query (k, a) -> Tabulation k a
264+fromQuery = Tabulation . const . fmap (first pure)
265+
266+
267+-- | Convert a @'Tabulation' k a@ back into a 'Query' of key-value pairs.
133268--
134−-- [Tabulation by primary key]:
135−-- @
136−-- projectsById :: Project 'Expr' -> 'Tabulation' ('Expr' ProjectId) (Project 'Expr')
137−-- projectsById = 'tabulate' projectId
138−-- @
269+-- Note that the result of a 'toQuery' is undefined (will always return zero
270+-- rows) on 'Tabulation's constructed with 'liftQuery' or 'pure'. So while
271+-- @toQuery . fromQuery@ is always @id@, @fromQuery . toQuery@ is not.
272+--
273+-- A safer, more predictable alternative to 'toQuery' is to use 'lookup' with
274+-- an explicit set of keys:
275+--
276+-- @
277+-- do
278+-- k <- keys
279+-- a <- lookup k tabulation
280+-- pure (k, a)
281+-- @
139282--
140−-- Note: the nature of primary keys means that each key will be mapped to a
141−-- singleton value in this case.
283+-- Having said that, in practice, most legitimate uses of 'Tabulation' will
284+-- have a well-defined 'toQuery'. It would be possible in theory to encode
285+-- the necessary invariants at the type level using an indexed monad, but we
286+-- would lose the ability to use @do@-notation, which is the main benefit
287+-- of having 'Tabulation' as a monad in the first place.
142288--
143−-- [Tabulation by other unique key]:
144−-- @
145−-- projectsByName :: Project 'Expr' -> 'Tabulation' ('Expr' Text) (Project 'Expr')
146−-- projectsByName = 'tabulate' projectName
147−-- @
289+-- In particular, @'toQuery' t@ is well-defined for any 'Tabulation' @t@
290+-- defined as @t = fromQuery _@. @'toQuery' t@ is also well-defined for any
291+-- 'Tabulation' @t@ defined as @t = t' >>= _@ or @t = t' *> _@ where
292+-- @'toQuery' t'@ is well-defined. There are other valid permutations too.
293+-- Generally, anything that uses 'fromQuery' at some point, unless wrapped in
294+-- a top-level 'present' or 'absent', will have a well-defined 'toQuery'.
295+toQuery :: Table Expr k => Tabulation k a -> Query (k, a)
296+toQuery (Tabulation f) = do
297+ (mk, a) <- f mempty
298+ k <- cat mk
299+ pure (k, a)
300+
301+
302+-- | A @'Query' a@ can be treated as a @'Tabulation' k a@ where the given @a@
303+-- values exist at every possible key @k@.
304+liftQuery :: Query a -> Tabulation k a
305+liftQuery = Tabulation . const . fmap (empty,)
306+
307+
308+-- | Run a Kleisli arrow in the the 'Query' monad \"through\" a 'Tabulation'.
309+-- Useful for 'Rel8.filter'ing a 'Tabulation'.
148310--
149−-- [Tabulation by foreign key (tabulate a child table by parent key)]:
150−-- @
151−-- revisionsByProjectId :: Revision 'Expr' -> 'Tabulation' ('Expr' ProjectId) (Revision 'Expr')
152−-- revisionsByProjectId = 'tabulate' revisionProjectId
153−-- @
154−tabulate :: (a -> k) -> a -> Tabulation k a
155−tabulate key a = fromQuery $ pure (key a, a)
311+-- @
312+-- 'Rel8.filter' ((>=. 30) . userAge) `'through'` usersById
313+-- @
314+through :: (a -> Query b) -> Tabulation k a -> Tabulation k b
315+through f (Tabulation as) = Tabulation $ \p -> do
316+ (k, a) <- as p
317+ b <- f a
318+ pure (k, b)
319+infixr 1 `through`
156320
157321
158−-- | Like 'tabulate' but takes a monadic 'Query' function instead of a pure
159−-- one. This means you can filter rows while calculating the key, which is
160−-- useful in conjunction with 'Rel8.Extra.catNulls'.
161−tabulateA :: (a -> Query k) -> a -> Tabulation k a
162−tabulateA key a = fromQuery $ (,a) <$> key a
322+-- | @'lookup' k t@ returns the value(s) at the key @k@ in the tabulation @t@.
323+lookup :: EqTable k => k -> Tabulation k a -> Query a
324+lookup k (Tabulation f) = do
325+ (k', a) <- f p
326+ ensure p k'
327+ pure a
328+ where
329+ p = match (pure k)
163330
164331
165−-- | Analgous to 'Data.Map.Strict.fromList'.
166−fromQuery :: Query (k, a) -> Tabulation k a
167−fromQuery = Tabulation . const . fmap (first Just)
332+-- | 'aggregate' aggregates the values within each key of a
333+-- 'Tabulation'. There is an implicit @GROUP BY@ on all the key columns.
334+aggregate :: forall k aggregates exprs.
335+ ( EqTable k
336+ , Aggregates aggregates exprs
337+ )
338+ => Tabulation k aggregates -> Tabulation k exprs
339+aggregate (Tabulation f) = Tabulation $
340+ mapOpaleye (Opaleye.aggregate (keyed haggregator aggregator)) .
341+ fmap (first (fmap (hgroupBy (eqTable @k) . toColumns))) .
342+ f
343+ where
344+ haggregator = dimap fromColumns fromCols aggregator
168345
169346
170−indexed :: Tabulation k a -> Tabulation k (k, a)
171−indexed (Tabulation query) = Tabulation $ \i ->
172− (\(mk, a) -> (mk, (fromMaybe i mk, a))) <$> query i
347+-- | 'distinct' ensures a 'Tabulation' has at most one value for
348+-- each key, i.e., it drops duplicates. In general it keeps only the
349+-- \"first\" value it encounters for each key, but note that \"first\" is
350+-- undefined unless you first call 'order'.
351+distinct :: EqTable k => Tabulation k a -> Tabulation k a
352+distinct (Tabulation f) = Tabulation $
353+ mapOpaleye (Opaleye.distinctOnExplicit (key unpackspec) fst) . f
173354
174355
175−ifilter :: (k -> a -> Expr Bool) -> Tabulation k a -> Tabulation k a
176−ifilter f tabulation = snd <$> do
177− filter (uncurry f) `postbind` indexed tabulation
356+-- | 'order' orders the /values/ of a 'Tabulation' within their
357+-- respective keys. This specifies a defined order for 'distinct'.
358+-- It also defines the order of the lists produced by 'many' and
359+-- 'some'.
360+order :: OrdTable k => Order a -> Tabulation k a -> Tabulation k a
361+order ordering (Tabulation f) =
362+ Tabulation $ mapOpaleye (Opaleye.orderBy ordering') . f
363+ where
364+ Order ordering' = runClown (keyed (Clown ascTable) (Clown ordering))
178365
179366
180−-- | Map a 'Query' over the input side of a 'Tabulation'.
181−prebind :: (a -> Tabulation k b) -> Query a -> Tabulation k b
182−prebind f as = Tabulation $ \k -> do
183− a <- as
184− case f a of
185− Tabulation query -> query k
186−infixr 1 `prebind`
367+-- $magic
368+--
369+-- Some of the following combinators produce \"magic\" 'Tabulation's. Let's
370+-- use 'count' as an example to demonstrate this concept. Consider
371+-- the following:
372+--
373+-- @
374+-- count $ fromQuery $ values
375+-- [ (lit 'a', lit True)
376+-- , (lit 'a', lit False)
377+-- , (lit 'b', lit True)
378+-- ]
379+-- @
380+--
381+-- You might expect this to be equivalent to the following 'Tabulation':
382+--
383+-- @
384+-- fromQuery $ values
385+-- [ (lit 'a', 2)
386+-- , (lit 'b', 1)
387+-- ]
388+-- @
389+--
390+-- However, it isn't quite. While the resulting 'Tabulation' does effectively
391+-- contain the above entries, it also behaves as though it contained the value
392+-- @0@ at every other possible key.
393+--
394+-- This means you can do:
395+--
396+-- @
397+-- do
398+-- user <- usersById
399+-- orderCount <- count ordersByUserId
400+-- @
401+--
402+-- To see how many orders a user has (getting @0@ if they have no orders).
187403
188404
189−-- | Map a 'Query' over the output side of a 'Tabulation'.
190−postbind :: (a -> Query b) -> Tabulation k a -> Tabulation k b
191−postbind f (Tabulation as) = Tabulation $ \i -> do
192− (k, a) <- as i
193− case f a of
194− bs -> do
195− b <- bs
196− pure (k, b)
197−infixr 1 `postbind`
405+-- | 'count' returns a count of how many entries are in the given
406+-- 'Tabulation' at each key.
407+--
408+-- The resulting 'Tabulation' is \"magic\" in that the value @0@ exists at
409+-- every possible key that wasn't in the given 'Tabulation'.
410+count :: EqTable k => Tabulation k a -> Tabulation k (Expr Int64)
411+count =
412+ fmap (maybeTable 0 id) .
413+ optional .
414+ aggregate .
415+ fmap (const countStar)
416+
417+
418+-- | 'optional' produces a \"magic\" 'Tabulation' whereby each
419+-- entry in the given 'Tabulation' is wrapped in 'Rel8.justTable', and every
420+-- other possible key contains a single 'Rel8.nothingTable'.
421+--
422+-- This is used to implement 'leftAlignWith'.
423+optional :: Tabulation k a -> Tabulation k (MaybeTable Expr a)
424+optional (Tabulation f) = Tabulation $ \p -> case p of
425+ Predicate Nothing -> fmap pure <$> f p
426+ _ -> fmap (\m -> (empty, snd <$> m)) $ Q.optional $ do
427+ (k, a) <- f p
428+ ensure p k
429+ pure (k, a)
430+
431+
432+-- | 'many' aggregates each entry with a particular key into a
433+-- single entry with all of the values contained in a 'ListTable'.
434+--
435+-- 'order' can be used to give this 'ListTable' a defined order.
436+--
437+-- The resulting 'Tabulation' is \"magic\" in that the value
438+-- @'Rel8.listTable []'@ exists at every possible key that wasn't in the given
439+-- 'Tabulation'.
440+many :: (EqTable k, Table Expr a)
441+ => Tabulation k a -> Tabulation k (ListTable Expr a)
442+many =
443+ fmap (maybeTable mempty (\(ListTable a) -> ListTable a)) .
444+ optional .
445+ aggregate .
446+ fmap (listAgg . toCols)
447+
448+
449+-- | 'some' aggregates each entry with a particular key into a
450+-- single entry with all of the values contained in a 'NonEmptyTable'.
451+--
452+-- 'order' can be used to give this 'NonEmptyTable' a defined order.
453+some :: (EqTable k, Table Expr a)
454+ => Tabulation k a -> Tabulation k (NonEmptyTable Expr a)
455+some =
456+ fmap (\(NonEmptyTable a) -> NonEmptyTable a) .
457+ aggregate .
458+ fmap (nonEmptyAgg . toCols)
459+
460+
461+-- | 'exists' produces a \"magic\" 'Tabulation' which contains the
462+-- value 'Rel8.true' at each key in the given 'Tabulation', and the value
463+-- 'Rel8.false' at every other possible key.
464+exists :: Tabulation k a -> Tabulation k (Expr Bool)
465+exists (Tabulation f) = Tabulation $ \p -> case p of
466+ Predicate Nothing -> (true <$) <$> f p
467+ _ -> fmap (empty,) $ Q.exists $ do
468+ (k, _) <- f p
469+ ensure p k
470+
471+
472+-- | 'present' produces a 'Tabulation' where a single @()@ row
473+-- exists for every key that was present in the given 'Tabulation'.
474+--
475+-- This is used to implement 'similarity'.
476+present :: Tabulation k a -> Tabulation k ()
477+present (Tabulation f) = Tabulation $ \p -> do
478+ Q.present $ do
479+ (k, _) <- f p
480+ ensure p k
481+ pure (empty, ())
198482
199483
200−-- | Note that because 'Tabulation' is a @MultiMap@, the 'Query' returned by
201−-- 'lookup' can and often does contain multiple results.
202−lookup :: EqTable k => k -> Tabulation k a -> Query a
203−lookup key (Tabulation query) = do
204− (mk, a) <- query key
205− traverse_ (where_ . (key ==:)) mk
206− pure a
484+-- | 'absent' produces a 'Tabulation' where a single @()@ row exists
485+-- at every possible key that absent from the given 'Tabulation'.
486+--
487+-- This is used to implement 'difference'.
488+absent :: Tabulation k a -> Tabulation k ()
489+absent (Tabulation f) = Tabulation $ \p -> do
490+ Q.absent $ do
491+ (k, _) <- f p
492+ ensure p k
493+ pure (empty, ())
207494
208495
209−-- | Analagous to
210−-- [@align@](https://hackage.haskell.org/package/semialign/docs/Data-Semialign.html#v:align).
496+-- | Performs a @NATURAL FULL OUTER JOIN@ based on the common key columns.
211497--
212−-- If 'zip' makes an @INNER JOIN@, then 'align' makes a @FULL OUTER JOIN@.
213−align :: (EqTable k, Table Expr a, Table Expr b)
214− => Tabulation k a -> Tabulation k b -> Tabulation k (TheseTable a b)
498+-- Analogous to 'Data.Semialign.align'.
499+align :: EqTable k
500+ => Tabulation k a -> Tabulation k b -> Tabulation k (TheseTable Expr a b)
215501align = alignWith id
216502
217503
218−-- | Analagous to
219−-- [@alignWith@](https://hackage.haskell.org/package/semialign/docs/Data-Semialign.html#v:alignWith).
504+-- | Performs a @NATURAL FULL OUTER JOIN@ based on the common key columns.
220505--
221−-- See 'zipWith' and 'align'.
222−alignWith :: (EqTable k, Table Expr a, Table Expr b)
223− => (TheseTable a b -> c)
506+-- Analogous to 'Data.Semialign.alignWith'.
507+alignWith :: EqTable k
508+ => (TheseTable Expr a b -> c)
224509 -> Tabulation k a -> Tabulation k b -> Tabulation k c
225−alignWith f kas kbs = do
226− as <- toQuery kas
227− bs <- toQuery kbs
228− fromQuery $ do
229− tkab <- alignBy (\(l, _) (m, _) -> l ==: m) as bs
230− let
231− k' = theseTable fst fst (const fst) tkab
232− tab = bimap snd snd tkab
233− pure (k', f tab)
234−
235−
236−-- | If 'zip' makes an @INNER JOIN@, then 'leftAlign' makes a @LEFT JOIN@.
237−-- This means it will return at least one row for every row in the left
238−-- 'Tabulation', even if there is no corresponding row in the right (hence the
239−-- 'Rel8.MaybeTable').
240−--
241−-- Analagous to
242−-- [@rpadZip@](https://hackage.haskell.org/package/semialign/docs/Data-Semialign.html#v:rpadZip).
510+alignWith f (Tabulation as) (Tabulation bs) = Tabulation $ \p -> do
511+ tkab <- liftF2 (alignBy condition) as bs p
512+ k <- traverse (rebind "key") $ recover $ bimap fst fst tkab
513+ let
514+ tab = bimap snd snd tkab
515+ pure (k, f tab)
516+ where
517+ condition (k, _) (k', _) = fromMaybe true (liftA2 (==:) k k')
518+ recover (TheseTable mma@(MaybeTable _ ma) mmb@(MaybeTable _ mb)) =
519+ case extract ma of
520+ Nothing -> extract mb
521+ Just a -> case extract mb of
522+ Nothing -> extract ma
523+ Just b -> case a <$ mma <|>: b <$ mmb of
524+ MaybeTable _ c -> pure (extract c)
525+
526+
527+-- | Performs a @NATURAL LEFT OUTER JOIN@ based on the common key columns.
528+--
529+-- Analogous to 'Data.Semialign.rpadZip'.
530+--
531+-- Note that you can achieve the same effect with 'optional' and the
532+-- 'Applicative' instance for 'Tabulation', i.e., this is just
533+-- @\left right -> liftA2 (,) left (optional right). You can also
534+-- use @do@-notation.
243535leftAlign :: EqTable k
244− => Tabulation k a -> Tabulation k b -> Tabulation k (a, MaybeTable b)
536+ => Tabulation k a -> Tabulation k b -> Tabulation k (a, MaybeTable Expr b)
245537leftAlign = leftAlignWith (,)
246538
247539
248−-- | See 'zipWith' and 'leftAlign'.
540+-- | Performs a @NATURAL LEFT OUTER JOIN@ based on the common key columns.
249541--
250−-- Analagous to
251−-- [@rpadZipWith@](https://hackage.haskell.org/package/semialign/docs/Data-Semialign.html#v:rpadZipWith).
542+-- Analogous to 'Data.Semialign.rpadZipWith'.
543+--
544+-- Note that you can achieve the same effect with 'optional' and the
545+-- 'Applicative' instance for 'Tabulation', i.e., this is just
546+-- @\f left right -> liftA2 f left (optional right). You can also
547+-- use @do@-notation.
252548leftAlignWith :: EqTable k
253− => (a -> MaybeTable b -> c)
549+ => (a -> MaybeTable Expr b -> c)
254550 -> Tabulation k a -> Tabulation k b -> Tabulation k c
255−leftAlignWith f left right = liftA2 f left (optionalTabulation right)
551+leftAlignWith f left right = liftA2 f left (optional right)
256552
257553
258−-- | Analagous to
259−-- [@zip@](https://hackage.haskell.org/package/semialign/docs/Data-Semialign.html#v:zip).
554+-- | Performs a @NATURAL RIGHT OUTER JOIN@ based on the common key columns.
555+--
556+-- Analogous to 'Data.Semialign.lpadZip'.
260557--
261−-- There are multiple correct ways of understanding what this does.
558+-- Note that you can achieve the same effect with 'optional' and the
559+-- 'Applicative' instance for 'Tabulation', i.e., this is just
560+-- @\left right -> liftA2 (flip (,)) right (optional left). You can
561+-- also use @do@-notation.
562+rightAlign :: EqTable k
563+ => Tabulation k a -> Tabulation k b -> Tabulation k (MaybeTable Expr a, b)
564+rightAlign = rightAlignWith (,)
565+
566+
567+-- | Performs a @NATURAL RIGHT OUTER JOIN@ based on the common key columns.
262568--
263−-- You can think of it as @'Data.Map.Strict.intersectionWith'
264−-- ('Control.Applicative.liftA2' (,))@. That is, @intersect@ the two
265−-- `Tabulation`s by matching their keys together (with 'Rel8.==:'), and combine
266−-- their values (remembering that 'Tabulation' is a 'MultiMap' so that the
267−-- values are keys) by getting their cartesian product.
569+-- Analogous to 'Data.Semialign.lpadZipWith'.
268570--
269−-- You can think of it as performing a cross product of the underlying 'Query's
270−-- of the given 'Tabulation's and filtering the results for 'match'ing keys.
571+-- Note that you can achieve the same effect with 'optional' and the
572+-- 'Applicative' instance for 'Tabulation', i.e., this is just
573+-- @\f left right -> liftA2 (flip f) right (optional left). You can
574+-- also use @do@-notation.
575+rightAlignWith :: EqTable k
576+ => (MaybeTable Expr a -> b -> c)
577+ -> Tabulation k a -> Tabulation k b -> Tabulation k c
578+rightAlignWith f left right = liftA2 (flip f) right (optional left)
579+
580+
581+-- | Performs a @NATURAL INNER JOIN@ based on the common key columns.
271582--
272−-- You can think of it as a natural join in SQL terms.
583+-- Analagous to 'Data.Semialign.zip'.
273584--
274−-- The size of the resulting 'Tabulation' will be \(\sum_{k} min(n_k, m_k) \)
275−-- in terms of the number of keys, but \(\sum_{k} n_k \times m_k\) in terms of
276−-- the number of values.
585+-- Note that you can achieve the same effect with the 'Applicative' instance
586+-- of 'Tabulation', i.e., this is just @'liftA2 (,)'@. You can also use
587+-- @do@-notation.
277588zip :: EqTable k
278589 => Tabulation k a -> Tabulation k b -> Tabulation k (a, b)
279590zip = zipWith (,)
280591
281592
282−-- | Analagous to
283−-- [@zipWith@](https://hackage.haskell.org/package/semialign/docs/Data-Semialign.html#v:zipWith).
593+-- | Performs a @NATURAL INNER JOIN@ based on the common key columns.
284594--
285−-- See 'zip'.
595+-- Analagous to 'Data.Semialign.zipWith'.
596+--
597+-- Note that you can achieve the same effect with the 'Applicative' instance
598+-- of 'Tabulation', i.e., this is just @'liftA2'@. You can also use
599+-- @do@-notation.
286600zipWith :: EqTable k
287601 => (a -> b -> c) -> Tabulation k a -> Tabulation k b -> Tabulation k c
288602zipWith = liftA2
289603
290604
291−-- | 'similarity' returns all the entries in the left 'Tabulation' that have a
292−-- corresponding entry in the right 'Tabulation'. This corresponds to a
293−-- semijoin in relational algebra.
605+-- | Performs a [@NATURAL SEMI JOIN@](https://en.wikipedia.org/wiki/Relational_algebra#Semijoin_%28%E2%8B%89%29%28%E2%8B%8A%29)
606+-- based on the common key columns.
294607--
295−-- This differs from @'zipWith' const x y@ when the right 'Tabulation' @y@
296−-- contains an entry with multiple rows. For 'similarity', the entries in the
297−-- resulting 'Tabulation' will contain the same number of rows as their
298−-- respective entries in the left 'Tabulation' @x@. With `zipWith const x y`,
299−-- each entry would contain the /product/ of the number of rows of their
300−-- respective entries in @x@ and @y@.
608+-- The result is a subset of the left tabulation where only entries which have
609+-- a corresponding entry in the right tabulation are kept.
301610--
302−-- See 'Rel8.with'.
611+-- Note that you can achieve a similar effect with 'present' and the
612+-- 'Applicative' instance of 'Tabulation', i.e., this is just
613+-- @\left right -> left <* present right@. You can also use
614+-- @do@-notation.
303615similarity :: EqTable k => Tabulation k a -> Tabulation k b -> Tabulation k a
304−similarity kas kbs = do
305− as <- toQuery kas
306− bs <- toQuery kbs
307− fromQuery $ as >>= withBy (\(k, _) (l, _) -> k ==: l) bs
616+similarity a b = a <* present b
308617
309618
310−-- | 'difference' returns all the entries in the left 'Tabulation' that don't
311−-- exist in the right 'Tabulation'. This corresponds to an antijoin in
312−-- relational algebra.
619+-- | Performs a [@NATURAL ANTI JOIN@](https://en.wikipedia.org/wiki/Relational_algebra#Antijoin_%28%E2%96%B7%29)
620+-- based on the common key columns.
621+--
622+-- The result is a subset of the left tabulation where only entries which do
623+-- not have a corresponding entry in the right tabulation are kept.
313624--
314−-- See 'Rel8.without'.
625+-- Note that you can achieve a similar effect with 'absent' and the
626+-- 'Applicative' instance of 'Tabulation', i.e., this is just
627+-- @\left right -> left <* absent right@. You can also use
628+-- @do@-notation.
315629difference :: EqTable k => Tabulation k a -> Tabulation k b -> Tabulation k a
316−difference kas kbs = do
317− as <- toQuery kas
318− bs <- toQuery kbs
319− fromQuery $ as >>= withoutBy (\(k, _) (l, _) -> k ==: l) bs
320−
321−
322−aggregateTabulation :: EqTable k
323− => Tabulation k (Aggregate a) -> Tabulation k a
324−aggregateTabulation kas = do
325− as <- toQuery kas
326− fromQuery $ aggregate $ bitraverse1 groupBy id <$> as
327−
328−
329−optionalTabulation :: EqTable k
330− => Tabulation k a -> Tabulation k (MaybeTable a)
331−optionalTabulation as = Tabulation $ \k -> do
332− ma <- optional $ lookup k as
333− pure (Just k, ma)
630+difference a b = a <* absent b
334631
335632
336−toQuery :: Tabulation k a -> Tabulation k (Query (k, a))
337−toQuery (Tabulation as) = Tabulation $ \k ->
338− pure (Nothing, first (fromMaybe k) <$> as k)
633+-- | 'Tabulation's can be produced with either 'fromQuery' or 'liftQuery', and
634+-- in some cases we might want to treat these differently. 'peek' uses
635+-- 'unsafePeekQuery' to determine which type of 'Tabulation' we have.
636+peek :: Tabulation k a -> Tabulation k (Either (Query a) (Query (k, a)))
637+peek (Tabulation f) = Tabulation $ \p ->
638+ pure $ (empty,) $ case unsafePeekQuery (f p) of
639+ (Nothing, _) -> Left $ fmap snd (f p)
640+ (Just _, _) -> Right $ fmap (first fromJust) (f p)
src/Rel8/Type.hs+9−8
@@ -1,3 +1,4 @@
1+{-# language FlexibleContexts #-}
12{-# language FlexibleInstances #-}
23{-# language MonoLocalBinds #-}
34{-# language MultiWayIf #-}
@@ -127,10 +128,10 @@ instance DBType Int64 where
127128instance DBType Float where
128129 typeInformation = TypeInformation
129130 { encode = \x -> Opaleye.ConstExpr
130− if | x == (1 /0) -> Opaleye.OtherLit "'Infinity'"
131− | isNaN x -> Opaleye.OtherLit "'NaN'"
132− | x == (-1/0) -> Opaleye.OtherLit "'-Infinity'"
133− | otherwise -> Opaleye.NumericLit $ realToFrac x
131+ if | x == (1 / 0) -> Opaleye.OtherLit "'Infinity'"
132+ | isNaN x -> Opaleye.OtherLit "'NaN'"
133+ | x == (-1 / 0) -> Opaleye.OtherLit "'-Infinity'"
134+ | otherwise -> Opaleye.NumericLit $ realToFrac x
134135 , decode = Hasql.float4
135136 , typeName = "float4"
136137 }
@@ -140,10 +141,10 @@ instance DBType Float where
140141instance DBType Double where
141142 typeInformation = TypeInformation
142143 { encode = \x -> Opaleye.ConstExpr
143− if | x == (1 /0) -> Opaleye.OtherLit "'Infinity'"
144− | isNaN x -> Opaleye.OtherLit "'NaN'"
145− | x == (-1/0) -> Opaleye.OtherLit "'-Infinity'"
146− | otherwise -> Opaleye.NumericLit $ realToFrac x
144+ if | x == (1 / 0) -> Opaleye.OtherLit "'Infinity'"
145+ | isNaN x -> Opaleye.OtherLit "'NaN'"
146+ | x == (-1 / 0) -> Opaleye.OtherLit "'-Infinity'"
147+ | otherwise -> Opaleye.NumericLit $ realToFrac x
147148 , decode = Hasql.float8
148149 , typeName = "float8"
149150 }
src/Rel8/Type/Array.hs+46−26
@@ -1,12 +1,13 @@
11{-# language GADTs #-}
2+{-# language LambdaCase #-}
23{-# language NamedFieldPuns #-}
34{-# language OverloadedStrings #-}
5+{-# language ViewPatterns #-}
46
57module Rel8.Type.Array
6− ( array
8+ ( array, encodeArrayElement, extractArrayElement
79 , listTypeInformation
810 , nonEmptyTypeInformation
9− , fromPrimArray, toPrimArray, zipPrimArraysWith
1011 )
1112where
1213
@@ -28,10 +29,9 @@ import Rel8.Type.Information ( TypeInformation(..), parseTypeInformation )
2829
2930array :: Foldable f
3031 => TypeInformation a -> f Opaleye.PrimExpr -> Opaleye.PrimExpr
31−array TypeInformation {typeName} =
32− fromPrimArray .
33− Opaleye.CastExpr (typeName <> "[]") .
34− Opaleye.ArrayExpr . toList
32+array info =
33+ Opaleye.CastExpr (arrayType info <> "[]") .
34+ Opaleye.ArrayExpr . map (encodeArrayElement info) . toList
3535{-# INLINABLE array #-}
3636
3737
@@ -39,19 +39,23 @@ listTypeInformation :: ()
3939 => Nullity a
4040 -> TypeInformation (Unnullify a)
4141 -> TypeInformation [a]
42−listTypeInformation nullity info =
43− case info of
44− TypeInformation{ encode, decode } -> TypeInformation
45− { decode = row $ case nullity of
46− Null -> Hasql.listArray (Hasql.nullable decode)
47− NotNull -> Hasql.listArray (Hasql.nonNullable decode)
48− , encode = case nullity of
49− Null -> array info . fmap (maybe null encode)
50− NotNull -> array info . fmap encode
51− , typeName = "record"
52− }
42+listTypeInformation nullity info@TypeInformation {encode, decode} =
43+ TypeInformation
44+ { decode = case nullity of
45+ Null ->
46+ Hasql.listArray (decodeArrayElement info (Hasql.nullable decode))
47+ NotNull ->
48+ Hasql.listArray (decodeArrayElement info (Hasql.nonNullable decode))
49+ , encode = case nullity of
50+ Null ->
51+ Opaleye.ArrayExpr .
52+ fmap (encodeArrayElement info . maybe null encode)
53+ NotNull ->
54+ Opaleye.ArrayExpr .
55+ fmap (encodeArrayElement info . encode)
56+ , typeName = arrayType info <> "[]"
57+ }
5358 where
54− row = Hasql.composite . Hasql.field . Hasql.nonNullable
5559 null = Opaleye.ConstExpr Opaleye.NullLit
5660
5761
@@ -66,15 +70,31 @@ nonEmptyTypeInformation nullity =
6670 message = "failed to decode NonEmptyList: got empty list"
6771
6872
69−fromPrimArray :: Opaleye.PrimExpr -> Opaleye.PrimExpr
70−fromPrimArray = Opaleye.UnExpr (Opaleye.UnOpOther "ROW")
73+isArray :: TypeInformation a -> Bool
74+isArray = \case
75+ (reverse . typeName -> ']' : '[' : _) -> True
76+ _ -> False
7177
7278
73−toPrimArray :: Opaleye.PrimExpr -> Opaleye.PrimExpr
74−toPrimArray a = Opaleye.CompositeExpr a "f1"
79+arrayType :: TypeInformation a -> String
80+arrayType info
81+ | isArray info = "record"
82+ | otherwise = typeName info
7583
7684
77−zipPrimArraysWith :: ()
78− => (Opaleye.PrimExpr -> Opaleye.PrimExpr -> Opaleye.PrimExpr)
79− -> Opaleye.PrimExpr -> Opaleye.PrimExpr -> Opaleye.PrimExpr
80−zipPrimArraysWith f a b = fromPrimArray (f (toPrimArray a) (toPrimArray b))
85+decodeArrayElement :: TypeInformation a -> Hasql.NullableOrNot Hasql.Value x -> Hasql.NullableOrNot Hasql.Value x
86+decodeArrayElement info
87+ | isArray info = Hasql.nonNullable . Hasql.composite . Hasql.field
88+ | otherwise = id
89+
90+
91+encodeArrayElement :: TypeInformation a -> Opaleye.PrimExpr -> Opaleye.PrimExpr
92+encodeArrayElement info
93+ | isArray info = Opaleye.UnExpr (Opaleye.UnOpOther "ROW")
94+ | otherwise = id
95+
96+
97+extractArrayElement :: TypeInformation a -> Opaleye.PrimExpr -> Opaleye.PrimExpr
98+extractArrayElement info
99+ | isArray info = flip Opaleye.CompositeExpr "f1"
100+ | otherwise = id
src/Rel8/Type/Array1D.hsdeleted−139
@@ -1,139 +0,0 @@
1−{-# language DataKinds #-}
2−{-# language DeriveTraversable #-}
3−{-# language DerivingStrategies #-}
4−{-# language FlexibleContexts #-}
5−{-# language FlexibleInstances #-}
6−{-# language GeneralizedNewtypeDeriving #-}
7−{-# language NamedFieldPuns #-}
8−{-# language StandaloneKindSignatures #-}
9−{-# language TypeFamilies #-}
10−{-# language UndecidableInstances #-}
11−
12−{-# options_ghc -fno-warn-redundant-constraints #-}
13−
14−module Rel8.Type.Array1D
15− ( Array1D( Array1D )
16− , NotArray
17− , getArray1D
18− )
19−where
20−
21−-- aeson
22−import Data.Aeson
23− ( ToJSON
24− , ToJSON1
25− , ToJSONKey
26− , FromJSON
27− , FromJSON1
28− , FromJSONKey
29− )
30−
31−-- base
32−import Control.Applicative ( Alternative, (<|>) )
33−import Control.Monad ( MonadPlus )
34−import Data.Functor.Classes ( Eq1, Ord1, Read1, Show1 )
35−import Data.Kind ( Type )
36−import GHC.Exts ( IsList )
37−import Prelude hiding ( null )
38−
39−-- hasql
40−import qualified Hasql.Decoders as Hasql
41−
42−-- opaleye
43−import qualified Opaleye.Internal.HaskellDB.PrimQuery as Opaleye
44−
45−-- rel8
46−import Rel8.Expr.Opaleye ( zipPrimExprsWith )
47−import Rel8.Expr.Serialize ( litExpr )
48−import Rel8.Schema.Null ( Unnullify, Nullity( Null, NotNull ), Sql, nullable )
49−import Rel8.Type ( DBType, typeInformation )
50−import Rel8.Type.Eq ( DBEq )
51−import Rel8.Type.Information ( TypeInformation(..) )
52−import Rel8.Type.Monoid ( DBMonoid, memptyExpr )
53−import Rel8.Type.Ord ( DBMax, DBMin, DBOrd )
54−import Rel8.Type.Semigroup ( DBSemigroup, (<>.) )
55−
56−-- semigroupoids
57−import Data.Functor.Alt ( Alt, (<!>) )
58−import Data.Functor.Apply ( Apply )
59−import Data.Functor.Bind ( Bind )
60−import Data.Functor.Plus ( Plus )
61−
62−-- semialign
63−import Data.Align ( Align )
64−import Data.Semialign ( Semialign )
65−import Data.Zip ( Repeat, Unzip, Zip )
66−
67−
68−-- | A one dimensional array.
69−newtype Array1D a = Array1D [a]
70− deriving stock Traversable
71− deriving newtype
72− ( Eq, Ord, Read, Show, Semigroup, Monoid, IsList
73− , Functor, Foldable
74− , Eq1, Ord1, Read1, Show1
75− , FromJSON1, ToJSON1, FromJSON, FromJSONKey, ToJSON, ToJSONKey
76− , Apply, Applicative, Alternative, Plus, Bind, Monad, MonadPlus
77− , Align, Semialign, Repeat, Unzip, Zip
78− )
79−
80−
81−instance Alt Array1D where
82− (<!>) = (<|>)
83−
84−
85−getArray1D :: Array1D a -> [a]
86−getArray1D (Array1D a) = a
87−
88−
89−type IsArray1D :: Type -> Bool
90−type family IsArray1D a where
91− IsArray1D (Array1D _) = 'True
92− IsArray1D _ = 'False
93−
94−
95−class IsArray1D a ~ 'False => NotArray a
96−instance IsArray1D a ~ 'False => NotArray a
97−
98−
99−array1DTypeInformation :: Sql NotArray a
100− => Nullity a
101− -> TypeInformation (Unnullify a)
102− -> TypeInformation (Array1D a)
103−array1DTypeInformation nullity info =
104− case info of
105− TypeInformation{ encode, decode, typeName } -> TypeInformation
106− { decode = case nullity of
107− Null -> Array1D <$> Hasql.listArray (Hasql.nullable decode)
108− NotNull -> Array1D <$> Hasql.listArray (Hasql.nonNullable decode)
109− , encode = case nullity of
110− Null -> Opaleye.ArrayExpr . fmap (maybe null encode) . getArray1D
111− NotNull -> Opaleye.ArrayExpr . fmap encode . getArray1D
112− , typeName = typeName <> "[]"
113− }
114− where
115− null = Opaleye.ConstExpr Opaleye.NullLit
116−
117−
118−instance (Sql DBType a, Sql NotArray a) => DBType (Array1D a) where
119− typeInformation = array1DTypeInformation nullable typeInformation
120−
121−
122−instance (Sql DBEq a, Sql NotArray a) => DBEq (Array1D a)
123−
124−
125−instance (Sql DBOrd a, Sql NotArray a) => DBOrd (Array1D a)
126−
127−
128−instance (Sql DBMax a, Sql NotArray a) => DBMax (Array1D a)
129−
130−
131−instance (Sql DBMin a, Sql NotArray a) => DBMin (Array1D a)
132−
133−
134−instance (Sql DBType a, Sql NotArray a) => DBSemigroup (Array1D a) where
135− (<>.) = zipPrimExprsWith (Opaleye.BinExpr (Opaleye.:||))
136−
137−
138−instance (Sql DBType a, Sql NotArray a) => DBMonoid (Array1D a) where
139− memptyExpr = litExpr mempty
src/Rel8/Type/Composite.hs+90−39
@@ -1,27 +1,28 @@
1+{-# language AllowAmbiguousTypes #-}
2+{-# language BlockArguments #-}
13{-# language DataKinds #-}
24{-# language FlexibleContexts #-}
35{-# language GADTs #-}
6+{-# language NamedFieldPuns #-}
47{-# language ScopedTypeVariables #-}
58{-# language StandaloneKindSignatures #-}
69{-# language TypeApplications #-}
7−{-# language TypeOperators #-}
810{-# language UndecidableInstances #-}
11+{-# language UndecidableSuperClasses #-}
12+{-# language ViewPatterns #-}
913
1014module Rel8.Type.Composite
1115 ( Composite( Composite )
16+ , DBComposite( compositeFields, compositeTypeName )
17+ , compose, decompose
1218 )
1319where
1420
1521-- base
16−import Control.Applicative ( liftA2 )
22+import Data.Functor.Const ( Const( Const ), getConst )
23+import Data.Functor.Identity ( Identity( Identity ) )
1724import Data.Kind ( Constraint, Type )
18−import Data.Proxy ( Proxy( Proxy ) )
19−import GHC.Generics
20− ( Generic, Rep, from, to
21− , (:*:)( (:*:) ), K1( K1 ), M1( M1 )
22− )
23−import GHC.TypeLits ( KnownSymbol, Symbol, symbolVal )
24−import Prelude hiding ( null )
25+import Prelude
2526
2627-- hasql
2728import qualified Hasql.Decoders as Hasql
@@ -30,55 +31,105 @@ import qualified Hasql.Decoders as Hasql
3031import qualified Opaleye.Internal.HaskellDB.PrimQuery as Opaleye
3132
3233-- rel8
33−import Rel8.Schema.Null ( Nullity( Null, NotNull ), Sql, nullable )
34+import Rel8.Expr ( Expr )
35+import Rel8.Expr.Opaleye ( castExpr, fromPrimExpr, toPrimExpr )
36+import Rel8.Schema.HTable ( HTable, hfield, hspecs, htabulate, htabulateA )
37+import Rel8.Schema.Name ( Name( Name ) )
38+import Rel8.Schema.Null ( Nullity( Null, NotNull ) )
39+import Rel8.Schema.Result ( Result )
40+import Rel8.Schema.Spec ( Spec( Spec, nullity, info ) )
41+import Rel8.Table ( fromColumns, toColumns, fromResult, toResult )
42+import Rel8.Table.Eq ( EqTable )
43+import Rel8.Table.HKD ( HKD, HKDable )
44+import Rel8.Table.Ord ( OrdTable )
45+import Rel8.Table.Rel8able ()
46+import Rel8.Table.Serialize ( litHTable )
3447import Rel8.Type ( DBType, typeInformation )
48+import Rel8.Type.Eq ( DBEq )
3549import Rel8.Type.Information ( TypeInformation(..) )
50+import Rel8.Type.Ord ( DBOrd, DBMax, DBMin )
51+
52+-- semigroupoids
53+import Data.Functor.Apply ( WrappedApplicative(..) )
3654
3755
3856-- | A deriving-via helper type for column types that store a Haskell product
3957-- type in a single Postgres column using a Postgres composite type.
4058--
4159-- Note that this must map to a specific extant type in your database's schema
42−-- (created with @CREATE TYPE@). The @name@ parameter of @Composite@ should be
43−-- the name of this type.
44−type Composite :: Symbol -> Type -> Type
45−newtype Composite name a = Composite
60+-- (created with @CREATE TYPE@). Use 'DBComposite' to specify the name of this
61+-- Postgres type and the names of the individual fields (for projecting with
62+-- 'decompose').
63+type Composite :: Type -> Type
64+newtype Composite a = Composite
4665 { unComposite :: a
4766 }
4867
4968
50−instance (KnownSymbol name, Generic a, GComposite (Rep a)) =>
51− DBType (Composite name a)
52− where
69+instance DBComposite a => DBType (Composite a) where
5370 typeInformation = TypeInformation
54− { decode = Hasql.composite (Composite . to <$> gdecode @(Rep a))
55− , encode = Opaleye.FunExpr "ROW" . gencode @(Rep a) . from . unComposite
56− , typeName = symbolVal (Proxy @name)
71+ { decode = Hasql.composite (Composite . fromResult @_ @(HKD a Expr) <$> decoder)
72+ , encode = encoder . litHTable . toResult @_ @(HKD a Expr) . unComposite
73+ , typeName = compositeTypeName @a
5774 }
5875
5976
60−type GComposite :: (Type -> Type) -> Constraint
61−class GComposite rep where
62− gdecode :: Hasql.Composite (rep x)
63− gencode :: rep x -> [Opaleye.PrimExpr]
77+instance (DBComposite a, EqTable (HKD a Expr)) => DBEq (Composite a)
78+
79+
80+instance (DBComposite a, OrdTable (HKD a Expr)) => DBOrd (Composite a)
81+
82+
83+instance (DBComposite a, OrdTable (HKD a Expr)) => DBMax (Composite a)
6484
6585
66−instance GComposite rep => GComposite (M1 i c rep) where
67− gdecode = M1 <$> gdecode
68− gencode (M1 a) = gencode a
86+instance (DBComposite a, OrdTable (HKD a Expr)) => DBMin (Composite a)
6987
7088
71−instance (GComposite a, GComposite b) => GComposite (a :*: b) where
72− gdecode = liftA2 (:*:) gdecode gdecode
73− gencode (a :*: b) = gencode a <> gencode b
89+-- | 'DBComposite' is used to associate composite type metadata with a Haskell
90+-- type.
91+type DBComposite :: Type -> Constraint
92+class (DBType a, HKDable a) => DBComposite a where
93+ -- | The names of all fields in the composite type that @a@ maps to.
94+ compositeFields :: HKD a Name
7495
96+ -- | The name of the composite type that @a@ maps to.
97+ compositeTypeName :: String
7598
76−instance Sql DBType a => GComposite (K1 i a) where
77− gdecode = fmap K1 $ Hasql.field $ case nullable @a of
78− Null -> Hasql.nullable (decode typeInformation)
79− NotNull -> Hasql.nonNullable (decode typeInformation)
80− gencode (K1 a) = case nullable @a of
81− Null -> [maybe null (encode typeInformation) a]
82− NotNull -> [encode typeInformation a]
83− where
84− null = Opaleye.ConstExpr Opaleye.NullLit
99+
100+-- | Collapse a 'HKD' into a PostgreSQL composite type.
101+--
102+-- 'HKD' values are represented in queries by having a column for each field in
103+-- the corresponding Haskell type. 'compose' collapses these columns into a
104+-- single column expression, by combining them into a PostgreSQL composite
105+-- type.
106+compose :: DBComposite a => HKD a Expr -> Expr a
107+compose = castExpr . fromPrimExpr . encoder . toColumns
108+
109+
110+-- | Expand a composite type into a 'HKD'.
111+--
112+-- 'decompose' is the inverse of 'compose'.
113+decompose :: forall a. DBComposite a => Expr a -> HKD a Expr
114+decompose (toPrimExpr -> a) = fromColumns $ htabulate \field ->
115+ case hfield names field of
116+ Name name -> case hfield hspecs field of
117+ Spec {} -> fromPrimExpr $ Opaleye.CompositeExpr a name
118+ where
119+ names = toColumns (compositeFields @a)
120+
121+
122+decoder :: HTable t => Hasql.Composite (t Result)
123+decoder = unwrapApplicative $ htabulateA \field ->
124+ case hfield hspecs field of
125+ Spec {nullity, info} -> WrapApplicative $ Identity <$>
126+ case nullity of
127+ Null -> Hasql.field $ Hasql.nullable $ decode info
128+ NotNull -> Hasql.field $ Hasql.nonNullable $ decode info
129+
130+
131+encoder :: HTable t => t Expr -> Opaleye.PrimExpr
132+encoder a = Opaleye.FunExpr "ROW" exprs
133+ where
134+ exprs = getConst $ htabulateA \field -> case hfield a field of
135+ expr -> Const [toPrimExpr expr]
src/Rel8/Type/Enum.hs+86−33
@@ -1,27 +1,34 @@
1+{-# language AllowAmbiguousTypes #-}
12{-# language DataKinds #-}
23{-# language FlexibleContexts #-}
34{-# language FlexibleInstances #-}
4−{-# language GADTs #-}
5+{-# language LambdaCase #-}
6+{-# language RankNTypes #-}
57{-# language ScopedTypeVariables #-}
68{-# language StandaloneKindSignatures #-}
79{-# language TypeApplications #-}
10+{-# language TypeFamilies #-}
811{-# language TypeOperators #-}
912{-# language UndecidableInstances #-}
1013
1114module Rel8.Type.Enum
12− ( Enum(..)
15+ ( Enum( Enum )
16+ , DBEnum( enumValue, enumTypeName )
17+ , Enumable
1318 )
1419where
1520
1621-- base
22+import Control.Applicative ( (<|>) )
23+import Control.Arrow ( (&&&) )
1724import Data.Kind ( Constraint, Type )
1825import Data.Proxy ( Proxy( Proxy ) )
1926import GHC.Generics
2027 ( Generic, Rep, from, to
21− , (:+:)( L1, R1 ), M1( M1 ), U1( U1 ), Meta( MetaCons )
22− , D, C
28+ , (:+:)( L1, R1 ), M1( M1 ), U1( U1 )
29+ , D, C, Meta( MetaCons )
2330 )
24−import GHC.TypeLits ( KnownSymbol, Symbol, symbolVal )
31+import GHC.TypeLits ( KnownSymbol, symbolVal )
2532import Prelude hiding ( Enum )
2633
2734-- hasql
@@ -32,55 +39,101 @@ import qualified Opaleye.Internal.HaskellDB.PrimQuery as Opaleye
3239
3340-- rel8
3441import Rel8.Type ( DBType, typeInformation )
42+import Rel8.Type.Eq ( DBEq )
3543import Rel8.Type.Information ( TypeInformation(..) )
44+import Rel8.Type.Ord ( DBOrd, DBMax, DBMin )
3645
3746-- text
38−import Data.Text ( unpack )
47+import Data.Text ( pack )
3948
4049
4150-- | A deriving-via helper type for column types that store an \"enum\" type
4251-- (in Haskell terms, a sum type where all constructors are nullary) using a
4352-- Postgres @enum@ type.
4453--
45−-- Note that this must map to a specific type in your database's schema
46−-- (explicitly created with @CREATE TYPE ... AS ENUM@). The @name@ parameter
47−-- of @Enum@ should be the name of this type. Note also the names of the
48−-- Postgres @enum@'s values are assumed to match exactly the names of the
49−-- constructors of the Haskell type (up to and including case sensitivity).
50−type Enum :: Symbol -> Type -> Type
51−newtype Enum name a = Enum
54+-- Note that this should map to a specific type in your database's schema
55+-- (explicitly created with @CREATE TYPE ... AS ENUM@). Use 'DBEnum' to
56+-- specify the name of this Postgres type and the names of the individual
57+-- values. If left unspecified, the names of the values of the Postgres
58+-- @enum@ are assumed to match exactly exactly the names of the constructors
59+-- of the Haskell type (up to and including case sensitivity).
60+type Enum :: Type -> Type
61+newtype Enum a = Enum
5262 { unEnum :: a
5363 }
5464
5565
56−instance (KnownSymbol name, Generic a, GEnum (Rep a)) => DBType (Enum name a)
57− where
66+instance DBEnum a => DBType (Enum a) where
5867 typeInformation = TypeInformation
59− { decode = Hasql.enum ((`lookup` (fmap (Enum . to) <$> gdecode)) . unpack)
60− , encode = Opaleye.ConstExpr . Opaleye.StringLit . gencode . from . unEnum
61− , typeName = symbolVal (Proxy @name)
68+ { decode =
69+ Hasql.enum $
70+ flip lookup $
71+ map ((pack . enumValue &&& Enum) . to) $
72+ genumerate @(Rep a)
73+ , encode =
74+ Opaleye.ConstExpr .
75+ Opaleye.StringLit .
76+ enumValue @a .
77+ unEnum
78+ , typeName = enumTypeName @a
6279 }
6380
6481
65−type GEnum :: (Type -> Type) -> Constraint
66−class GEnum rep where
67− gdecode :: [(String, rep x)]
68− gencode :: rep x -> String
82+instance DBEnum a => DBEq (Enum a)
83+
84+
85+instance DBEnum a => DBOrd (Enum a)
86+
87+
88+instance DBEnum a => DBMax (Enum a)
89+
90+
91+instance DBEnum a => DBMin (Enum a)
92+
6993
94+-- | @DBEnum@ contains the necessary metadata to describe a PostgreSQL @enum@ type.
95+type DBEnum :: Type -> Constraint
96+class (DBType a, Enumable a) => DBEnum a where
97+ -- | Map Haskell values to the corresponding element of the @enum@ type. The
98+ -- default implementation of this method will use the exact name of the
99+ -- Haskell constructors.
100+ enumValue :: a -> String
101+ enumValue = gshow @(Rep a) . from
70102
71−instance GEnum rep => GEnum (M1 D c rep) where
72− gdecode = fmap M1 <$> gdecode
73− gencode (M1 a) = gencode a
103+ -- | The name of the PostgreSQL @enum@ type that @a@ maps to.
104+ enumTypeName :: String
74105
75106
76−instance (GEnum a, GEnum b) => GEnum (a :+: b) where
77− gdecode = (fmap L1 <$> gdecode) <> (fmap R1 <$> gdecode)
78− gencode (L1 a) = gencode a
79− gencode (R1 a) = gencode a
107+-- | Types that are sum types, where each constructor is unary (that is, has no
108+-- fields).
109+type Enumable :: Type -> Constraint
110+class (Generic a, GEnumable (Rep a)) => Enumable a
111+instance (Generic a, GEnumable (Rep a)) => Enumable a
80112
81113
82−instance (KnownSymbol name, a ~ U1) =>
83− GEnum (M1 C ('MetaCons name f r) a)
114+type GEnumable :: (Type -> Type) -> Constraint
115+class GEnumable rep where
116+ genumerate :: [rep x]
117+ gshow :: rep x -> String
118+
119+
120+instance GEnumable rep => GEnumable (M1 D meta rep) where
121+ genumerate = M1 <$> genumerate
122+ gshow (M1 rep) = gshow rep
123+
124+
125+instance (GEnumable a, GEnumable b) => GEnumable (a :+: b) where
126+ genumerate = L1 <$> genumerate <|> R1 <$> genumerate
127+ gshow = \case
128+ L1 a -> gshow a
129+ R1 a -> gshow a
130+
131+
132+instance
133+ ( meta ~ 'MetaCons name _fixity _isRecord
134+ , KnownSymbol name
135+ )
136+ => GEnumable (M1 C meta U1)
84137 where
85− gdecode = [(symbolVal (Proxy @name), M1 U1)]
86− gencode _ = symbolVal (Proxy @name)
138+ genumerate = [M1 U1]
139+ gshow (M1 U1) = symbolVal (Proxy @name)
src/Rel8/Type/JSONBEncoded.hs+4
@@ -1,3 +1,5 @@
1+{-# language StandaloneKindSignatures #-}
2+
13module Rel8.Type.JSONBEncoded ( JSONBEncoded(..) ) where
24
35-- aeson
@@ -6,6 +8,7 @@ import Data.Aeson.Types ( parseEither )
68
79-- base
810import Data.Bifunctor ( first )
11+import Data.Kind ( Type )
912import Prelude
1013
1114-- hasql
@@ -20,6 +23,7 @@ import Data.Text ( pack )
2023
2124
2225-- | Like 'Rel8.JSONEncoded', but works for @jsonb@ columns.
26+type JSONBEncoded :: Type -> Type
2327newtype JSONBEncoded a = JSONBEncoded { fromJSONBEncoded :: a }
2428
2529
src/Rel8/Type/JSONEncoded.hs+4
@@ -1,3 +1,5 @@
1+{-# language StandaloneKindSignatures #-}
2+
13module Rel8.Type.JSONEncoded ( JSONEncoded(..) ) where
24
35-- aeson
@@ -5,6 +7,7 @@ import Data.Aeson ( FromJSON, ToJSON, parseJSON, toJSON )
57import Data.Aeson.Types ( parseEither )
68
79-- base
10+import Data.Kind ( Type )
811import Prelude
912
1013-- rel8
@@ -15,6 +18,7 @@ import Rel8.Type.Information ( parseTypeInformation )
1518-- | A deriving-via helper type for column types that store a Haskell value
1619-- using a JSON encoding described by @aeson@'s 'ToJSON' and 'FromJSON' type
1720-- classes.
21+type JSONEncoded :: Type -> Type
1822newtype JSONEncoded a = JSONEncoded { fromJSONEncoded :: a }
1923
2024
src/Rel8/Type/Monoid.hs+2−2
@@ -27,7 +27,7 @@ import Data.CaseInsensitive ( CI )
2727import {-# SOURCE #-} Rel8.Expr ( Expr )
2828import Rel8.Expr.Array ( sempty )
2929import Rel8.Expr.Serialize ( litExpr )
30−import Rel8.Schema.Null ( Sql, nullable )
30+import Rel8.Schema.Null ( Sql )
3131import Rel8.Type ( DBType, typeInformation )
3232import Rel8.Type.Semigroup ( DBSemigroup )
3333
@@ -48,7 +48,7 @@ class DBSemigroup a => DBMonoid a where
4848
4949
5050instance Sql DBType a => DBMonoid [a] where
51− memptyExpr = sempty nullable typeInformation
51+ memptyExpr = sempty typeInformation
5252
5353
5454instance DBMonoid CalendarDiffTime where
src/Rel8/Type/Num.hs+11−2
@@ -7,7 +7,7 @@
77{-# language UndecidableInstances #-}
88
99module Rel8.Type.Num
10− ( DBNum, DBIntegral, DBFractional
10+ ( DBNum, DBIntegral, DBFractional, DBFloating
1111 )
1212where
1313
@@ -18,6 +18,7 @@ import Prelude
1818
1919-- rel8
2020import Rel8.Type ( DBType )
21+import Rel8.Type.Ord ( DBOrd )
2122
2223-- scientific
2324import Data.Scientific ( Scientific )
@@ -39,14 +40,22 @@ instance DBNum Scientific
3940-- expressions. This is a Rel8 concept, and allows us to provide
4041-- 'fromIntegral'.
4142type DBIntegral :: Type -> Constraint
42−class DBNum a => DBIntegral a
43+class (DBNum a, DBOrd a) => DBIntegral a
4344instance DBIntegral Int16
4445instance DBIntegral Int32
4546instance DBIntegral Int64
4647
4748
4849-- | The class of database types that support the @/@ operator.
50+type DBFractional :: Type -> Constraint
4951class DBNum a => DBFractional a
5052instance DBFractional Float
5153instance DBFractional Double
5254instance DBFractional Scientific
55+
56+
57+-- | The class of database types that support the @/@ operator.
58+type DBFloating :: Type -> Constraint
59+class DBFractional a => DBFloating a
60+instance DBFloating Float
61+instance DBFloating Double
src/Rel8/Type/Ord.hs−2
@@ -75,7 +75,6 @@ instance Sql DBOrd a => DBOrd (NonEmpty a)
7575-- | The class of database types that support the @max@ aggregation function.
7676type DBMax :: Type -> Constraint
7777class DBOrd a => DBMax a
78−instance DBMax Bool
7978instance DBMax Char
8079instance DBMax Int16
8180instance DBMax Int32
@@ -101,7 +100,6 @@ instance Sql DBMax a => DBMax (NonEmpty a)
101100-- | The class of database types that support the @min@ aggregation function.
102101type DBMin :: Type -> Constraint
103102class DBOrd a => DBMin a
104−instance DBMin Bool
105103instance DBMin Char
106104instance DBMin Int16
107105instance DBMin Int32
src/Rel8/Type/ReadShow.hs+3
@@ -1,10 +1,12 @@
11{-# language ScopedTypeVariables #-}
2+{-# language StandaloneKindSignatures #-}
23{-# language TypeApplications #-}
34{-# language ViewPatterns #-}
45
56module Rel8.Type.ReadShow ( ReadShow(..) ) where
67
78-- base
9+import Data.Kind ( Type )
810import Data.Proxy ( Proxy( Proxy ) )
911import Data.Typeable ( Typeable, typeRep )
1012import Prelude
@@ -20,6 +22,7 @@ import qualified Data.Text as Text
2022
2123-- | A deriving-via helper type for column types that store a Haskell value
2224-- using a Haskell's 'Read' and 'Show' type classes.
25+type ReadShow :: Type -> Type
2326newtype ReadShow a = ReadShow { fromReadShow :: a }
2427
2528
src/Rel8/Type/Semigroup.hs+4−2
@@ -1,3 +1,4 @@
1+{-# language BlockArguments #-}
12{-# language DataKinds #-}
23{-# language FlexibleContexts #-}
34{-# language FlexibleInstances #-}
@@ -28,6 +29,7 @@ import qualified Opaleye.Internal.HaskellDB.PrimQuery as Opaleye
2829
2930-- rel8
3031import {-# SOURCE #-} Rel8.Expr ( Expr )
32+import Rel8.Expr.Array ( sappend, sappend1 )
3133import Rel8.Expr.Opaleye ( zipPrimExprsWith )
3234import Rel8.Schema.Null ( Sql )
3335import Rel8.Type ( DBType )
@@ -50,11 +52,11 @@ class DBType a => DBSemigroup a where
5052
5153
5254instance Sql DBType a => DBSemigroup [a] where
53− (<>.) = zipPrimExprsWith (Opaleye.BinExpr (Opaleye.:||))
55+ (<>.) = sappend
5456
5557
5658instance Sql DBType a => DBSemigroup (NonEmpty a) where
57− (<>.) = zipPrimExprsWith (Opaleye.BinExpr (Opaleye.:||))
59+ (<>.) = sappend1
5860
5961
6062instance DBSemigroup CalendarDiffTime where
src/Rel8/Type/Tag.hs+14−1
@@ -1,11 +1,13 @@
11{-# language DataKinds #-}
22{-# language DeriveAnyClass #-}
33{-# language DerivingVia #-}
4+{-# language GeneralizedNewtypeDeriving #-}
45{-# language StandaloneKindSignatures #-}
56
67module Rel8.Type.Tag
78 ( EitherTag( IsLeft, IsRight ), isLeft, isRight
89 , MaybeTag( IsJust )
10+ , Tag( Tag )
911 )
1012where
1113
@@ -19,7 +21,7 @@ import Prelude
1921import qualified Opaleye.Internal.HaskellDB.PrimQuery as Opaleye
2022
2123-- rel8
22−import {-# SOURCE #-} Rel8.Expr ( Expr )
24+import Rel8.Expr ( Expr )
2325import Rel8.Expr.Eq ( (==.) )
2426import Rel8.Expr.Opaleye ( zipPrimExprsWith )
2527import Rel8.Expr.Serialize ( litExpr )
@@ -30,6 +32,9 @@ import Rel8.Type.Monoid ( DBMonoid, memptyExpr )
3032import Rel8.Type.Ord ( DBOrd )
3133import Rel8.Type.Semigroup ( DBSemigroup, (<>.) )
3234
35+-- text
36+import Data.Text ( Text )
37+
3338
3439type EitherTag :: Type
3540data EitherTag = IsLeft | IsRight
@@ -83,3 +88,11 @@ instance DBSemigroup MaybeTag where
8388
8489instance DBMonoid MaybeTag where
8590 memptyExpr = litExpr mempty
91+
92+
93+type Tag :: Type
94+newtype Tag = Tag Text
95+ deriving newtype
96+ ( Eq, Ord, Read, Show
97+ , DBType, DBEq, DBOrd
98+ )
src/Rel8/Window.hsnew file+97
@@ -0,0 +1,97 @@
1+{-# language DerivingVia #-}
2+{-# language FlexibleContexts #-}
3+{-# language GeneralizedNewtypeDeriving #-}
4+{-# language ScopedTypeVariables #-}
5+{-# language StandaloneKindSignatures #-}
6+{-# language TypeApplications #-}
7+
8+module Rel8.Window
9+ ( Window(..)
10+ , Partition
11+ , over
12+ , partitionBy
13+ , orderPartitionBy
14+ )
15+where
16+
17+-- base
18+import Data.Functor.Const ( Const( Const ), getConst )
19+import Data.Functor.Contravariant ( Contravariant, contramap )
20+import Data.Kind ( Type )
21+import Prelude
22+
23+-- opaleye
24+import qualified Opaleye.Internal.Window as Opaleye
25+import qualified Opaleye.Internal.PackMap as Opaleye
26+
27+-- profunctors
28+import Data.Profunctor ( Profunctor )
29+
30+-- product-profunctors
31+import Data.Profunctor.Product ( ProductProfunctor, (****), purePP )
32+
33+-- rel8
34+import Rel8.Expr.Opaleye ( toColumn, toPrimExpr )
35+import Rel8.Order( Order( Order ) )
36+import Rel8.Schema.HTable ( hfield, htabulateA )
37+import Rel8.Table ( Columns, toColumns )
38+import Rel8.Table.Eq ( EqTable )
39+
40+-- semigroupoids
41+import Data.Functor.Apply ( Apply, WrappedApplicative(..) )
42+
43+
44+-- | 'Window' is an applicative functor that represents expressions that
45+-- contain
46+-- [window functions](https://www.postgresql.org/docs/current/tutorial-window.html).
47+-- 'Rel8.Query.Window.window' can be used to
48+-- evaluate these expressions over a particular query.
49+type Window :: Type -> Type -> Type
50+newtype Window a b = Window (Opaleye.Windows a b)
51+ deriving newtype (Profunctor)
52+ deriving newtype (Functor, Applicative)
53+ deriving (Apply) via (WrappedApplicative (Window a))
54+
55+
56+instance ProductProfunctor Window where
57+ purePP = pure
58+ (****) = (<*>)
59+
60+
61+-- | In PostgreSQL, window functions must specify the \"window\" or
62+-- \"partition\" over which they operate. The syntax for this looks like:
63+-- @SUM(salary) OVER (PARTITION BY department)@. The Rel8 type 'Partition'
64+-- represents everything that comes after @OVER@.
65+--
66+-- 'Partition' is a 'Monoid', so 'Window's created with 'partitionBy' and
67+-- 'orderWindowBy' can be combined using '<>'.
68+type Partition :: Type -> Type
69+newtype Partition a = Partition (Opaleye.Window a)
70+ deriving newtype (Contravariant, Semigroup, Monoid)
71+
72+
73+-- | 'over' adds a 'Partition' to a 'Window' expression.
74+--
75+-- @@@
76+-- 'Rel8.Table.Window.cumulative' ('Rel8.Expr.Aggregate.sum' . salary) `over` 'partitionBy' department <> 'orderPartitionBy' (salary >$< 'Rel8.desc')
77+-- @@@
78+over :: Window a b -> Partition a -> Window a b
79+over (Window (Opaleye.Windows (Opaleye.PackMap w))) (Partition p) =
80+ Window $ Opaleye.Windows $ Opaleye.PackMap $ \f ->
81+ w (\(o, p') -> f (o, p' <> p))
82+infixl 1 `over`
83+
84+
85+-- | Restricts a window function to operate only the group of rows that share
86+-- the same value(s) for the given expression(s).
87+partitionBy :: forall b a. EqTable b => (a -> b) -> Partition a
88+partitionBy f =
89+ Partition $ contramap (toColumns . f) $ getConst $
90+ htabulateA @(Columns b) $ \field ->
91+ Const $ Opaleye.partitionBy (toColumn . toPrimExpr . (`hfield` field))
92+
93+
94+-- | Controls the order in which rows are processed by window functions. This
95+-- does not need to match the ordering of the overall query.
96+orderPartitionBy :: Order a -> Partition a
97+orderPartitionBy (Order ordering) = Partition $ Opaleye.orderPartitionBy ordering
tests/Main.hs+323−159
@@ -1,12 +1,11 @@
1+{-# language BangPatterns #-}
12{-# language BlockArguments #-}
2−{-# language DataKinds #-}
33{-# language DeriveAnyClass #-}
44{-# language DeriveGeneric #-}
55{-# language DerivingStrategies #-}
6−{-# language DisambiguateRecordFields #-}
76{-# language FlexibleContexts #-}
87{-# language FlexibleInstances #-}
9−{-# language GADTs #-}
8+{-# language MonoLocalBinds #-}
109{-# language NamedFieldPuns #-}
1110{-# language OverloadedStrings #-}
1211{-# language RecordWildCards #-}
@@ -14,17 +13,15 @@
1413{-# language StandaloneDeriving #-}
1514{-# language TypeApplications #-}
1615
17−{-# options_ghc -fno-warn-redundant-constraints #-}
18−
1916module Main
2017 ( main
2118 )
2219where
2320
2421-- base
25−import Control.Applicative ( liftA2, liftA3 )
26−import Control.Monad (void)
27−import Control.Monad.IO.Class ( MonadIO, liftIO )
22+import Control.Applicative ( empty, liftA2, liftA3 )
23+import Control.Exception ( bracket, throwIO )
24+import Control.Monad ( (>=>), void )
2825import Data.Bifunctor ( bimap )
2926import Data.Foldable ( for_ )
3027import Data.Int ( Int32, Int64 )
@@ -38,25 +35,27 @@ import GHC.Generics ( Generic )
3835import qualified Data.ByteString.Lazy
3936
4037-- case-insensitive
41−import Data.CaseInsensitive (mk)
38+import Data.CaseInsensitive ( mk )
4239
4340-- containers
41+import Data.Containers.ListUtils ( nubOrdOn )
4442import qualified Data.Map.Strict as Map
4543
4644-- hasql
47−import Hasql.Connection ( Connection, acquire, release )
45+import Hasql.Connection ( Connection, acquire, release )
4846import Hasql.Session ( sql, run )
4947
48+-- hasql-transaction
49+import Hasql.Transaction ( Transaction, condemn, statement )
50+import qualified Hasql.Transaction.Sessions as Hasql
51+
5052-- hedgehog
5153import Hedgehog ( property, (===), forAll, cover, diff, evalM, PropertyT, TestT, test, Gen )
5254import qualified Hedgehog.Gen as Gen
5355import qualified Hedgehog.Range as Range
5456
55−-- lifted-base
56−import Control.Exception.Lifted ( bracket, throwIO, bracket_ )
57−
58−-- monad-control
59−import Control.Monad.Trans.Control ( MonadBaseControl )
57+-- mmorph
58+import Control.Monad.Morph ( hoist )
6059
6160-- rel8
6261import Rel8 ( Result )
@@ -72,12 +71,16 @@ import Test.Tasty
7271import Test.Tasty.Hedgehog ( testProperty )
7372
7473-- text
75−import Data.Text (Text, pack)
74+import Data.Text ( Text, pack, unpack )
7675import qualified Data.Text.Lazy
76+import Data.Text.Encoding ( decodeUtf8 )
7777
7878-- time
7979import Data.Time
8080
81+-- transformers
82+import Control.Monad.Trans.Class ( lift )
83+
8184-- tmp-postgres
8285import qualified Database.Postgres.Temp as TmpPostgres
8386
@@ -113,14 +116,17 @@ tests =
113116 , testCatMaybeTable getTestDatabase
114117 , testCatMaybe getTestDatabase
115118 , testMaybeTable getTestDatabase
119+ , testAggregateMaybeTable getTestDatabase
116120 , testNestedTables getTestDatabase
117121 , testMaybeTableApplicative getTestDatabase
118122 , testLogicalFixities getTestDatabase
119123 , testUpdate getTestDatabase
120124 , testDelete getTestDatabase
125+ , testUpsert getTestDatabase
121126 , testSelectNestedPairs getTestDatabase
122127 , testSelectArray getTestDatabase
123128 , testNestedMaybeTable getTestDatabase
129+ , testEvaluate getTestDatabase
124130 ]
125131
126132 where
@@ -132,25 +138,29 @@ tests =
132138 flip run conn do
133139 sql "CREATE EXTENSION citext"
134140 sql "CREATE TABLE test_table ( column1 text not null, column2 bool not null )"
141+ sql "CREATE TABLE unique_table ( \"key\" text not null unique, \"value\" text not null )"
142+ sql "CREATE SEQUENCE test_seq"
135143
136144 return db
137145
138146 stopTestDatabase = TmpPostgres.stop
139147
140148
149+connect :: TmpPostgres.DB -> IO Connection
150+connect = acquire . TmpPostgres.toConnectionString >=> either (maybe empty (fail . unpack . decodeUtf8)) pure
151+
152+
141153databasePropertyTest
142154 :: TestName
143− -> (((Connection -> TestT IO ()) -> PropertyT IO ()) -> PropertyT IO ())
155+ -> ((TestT Transaction () -> PropertyT IO ()) -> PropertyT IO ())
144156 -> IO TmpPostgres.DB -> TestTree
145157databasePropertyTest testName f getTestDatabase =
146− withResource connect release $ \c ->
158+ withResource (connect =<< getTestDatabase) release $ \c ->
147159 testProperty testName $ property do
148− connection <- liftIO c
149− f \g -> test $ rollingBack connection $ g connection
150−
151− where
152−
153− connect = either (error . show) return =<< acquire . TmpPostgres.toConnectionString =<< getTestDatabase
160+ connection <- lift c
161+ f $ test . hoist \m -> do
162+ e <- run (Hasql.transaction Hasql.Serializable Hasql.Write (m <* condemn)) connection
163+ either throwIO pure e
154164
155165
156166data TestTable f = TestTable
@@ -182,18 +192,17 @@ testSelectTestTable :: IO TmpPostgres.DB -> TestTree
182192testSelectTestTable = databasePropertyTest "Can SELECT TestTable" \transaction -> do
183193 rows <- forAll $ Gen.list (Range.linear 0 10) genTestTable
184194
185− transaction \connection -> do
186− void do
187− liftIO $ Rel8.insert connection
188− Rel8.Insert
189− { into = testTableSchema
190− , rows = map (Rel8.toInsert . Rel8.lit) rows
191− , onConflict = Rel8.DoNothing
192− , returning = Rel8.NumberOfRowsAffected
193− }
195+ transaction do
196+ selected <- lift do
197+ statement () $ Rel8.insert Rel8.Insert
198+ { into = testTableSchema
199+ , rows = Rel8.values $ map Rel8.lit rows
200+ , onConflict = Rel8.DoNothing
201+ , returning = pure ()
202+ }
194203
195− selected <- liftIO $ Rel8.select connection do
196− Rel8.each testTableSchema
204+ statement () $ Rel8.select do
205+ Rel8.each testTableSchema
197206
198207 sort selected === sort rows
199208
@@ -210,11 +219,12 @@ testWhere_ = databasePropertyTest "WHERE (Rel8.where_)" \transaction -> do
210219
211220 let expected = filter (\t -> testTableColumn2 t == magicBool) rows
212221
213− transaction \connection -> do
214− selected <- liftIO $ Rel8.select connection do
215− t <- Rel8.values $ Rel8.lit <$> rows
216− Rel8.where_ $ testTableColumn2 t Rel8.==. Rel8.lit magicBool
217− return t
222+ transaction do
223+ selected <- lift do
224+ statement () $ Rel8.select do
225+ t <- Rel8.values $ Rel8.lit <$> rows
226+ Rel8.where_ $ testTableColumn2 t Rel8.==. Rel8.lit magicBool
227+ return t
218228
219229 sort selected === sort expected
220230
@@ -227,11 +237,12 @@ testFilter :: IO TmpPostgres.DB -> TestTree
227237testFilter = databasePropertyTest "filter" \transaction -> do
228238 rows <- forAll $ Gen.list (Range.linear 1 10) genTestTable
229239
230− transaction \connection -> do
240+ transaction do
231241 let expected = filter testTableColumn2 rows
232242
233− selected <- liftIO $ Rel8.select connection
234− $ Rel8.filter testTableColumn2 =<< Rel8.values (Rel8.lit <$> rows)
243+ selected <- lift do
244+ statement () $ Rel8.select do
245+ Rel8.filter testTableColumn2 =<< Rel8.values (Rel8.lit <$> rows)
235246
236247 sort selected === sort expected
237248
@@ -246,9 +257,10 @@ testLimit = databasePropertyTest "LIMIT (Rel8.limit)" \transaction -> do
246257
247258 n <- forAll $ Gen.integral (Range.linear 0 10)
248259
249− transaction \connection -> do
250− selected <- liftIO $ Rel8.select connection do
251− Rel8.limit n $ Rel8.values (Rel8.lit <$> rows)
260+ transaction do
261+ selected <- lift do
262+ statement () $ Rel8.select do
263+ Rel8.limit n $ Rel8.values (Rel8.lit <$> rows)
252264
253265 diff (length selected) (<=) (fromIntegral n)
254266
@@ -266,9 +278,10 @@ testUnion = databasePropertyTest "UNION (Rel8.union)" \transaction -> evalM do
266278 left <- forAll $ Gen.list (Range.linear 0 10) genTestTable
267279 right <- forAll $ Gen.list (Range.linear 0 10) genTestTable
268280
269− transaction \connection -> do
270− selected <- liftIO $ Rel8.select connection do
271− Rel8.values (Rel8.lit <$> nub left) `Rel8.union` Rel8.values (Rel8.lit <$> nub right)
281+ transaction do
282+ selected <- lift do
283+ statement () $ Rel8.select do
284+ Rel8.values (Rel8.lit <$> nub left) `Rel8.union` Rel8.values (Rel8.lit <$> nub right)
272285
273286 sort selected === sort (nub (left ++ right))
274287
@@ -277,9 +290,11 @@ testDistinct :: IO TmpPostgres.DB -> TestTree
277290testDistinct = databasePropertyTest "DISTINCT (Rel8.distinct)" \transaction -> do
278291 rows <- forAll $ Gen.list (Range.linear 0 10) genTestTable
279292
280− transaction \connection -> do
281− selected <- liftIO $ Rel8.select connection $ Rel8.distinct do
282− Rel8.values (Rel8.lit <$> rows)
293+ transaction do
294+ selected <- lift do
295+ statement () $ Rel8.select do
296+ Rel8.distinct do
297+ Rel8.values (Rel8.lit <$> rows)
283298
284299 sort selected === nub (sort rows)
285300
@@ -292,8 +307,10 @@ testExists :: IO TmpPostgres.DB -> TestTree
292307testExists = databasePropertyTest "EXISTS (Rel8.exists)" \transaction -> do
293308 rows <- forAll $ Gen.list (Range.linear 0 10) genTestTable
294309
295− transaction \connection -> do
296− exists <- liftIO $ Rel8.select connection $ Rel8.exists $ Rel8.values $ Rel8.lit <$> rows
310+ transaction do
311+ exists <- lift do
312+ statement () $ Rel8.select do
313+ Rel8.exists $ Rel8.values $ Rel8.lit <$> rows
297314
298315 case rows of
299316 [] -> exists === [False]
@@ -304,9 +321,10 @@ testOptional :: IO TmpPostgres.DB -> TestTree
304321testOptional = databasePropertyTest "Rel8.optional" \transaction -> do
305322 rows <- forAll $ Gen.list (Range.linear 0 10) genTestTable
306323
307− transaction \connection -> do
308− selected <- liftIO $ Rel8.select connection do
309− Rel8.optional $ Rel8.values (Rel8.lit <$> rows)
324+ transaction do
325+ selected <- lift do
326+ statement () $ Rel8.select do
327+ Rel8.optional $ Rel8.values (Rel8.lit <$> rows)
310328
311329 case rows of
312330 [] -> selected === [Nothing]
@@ -317,9 +335,10 @@ testAnd :: IO TmpPostgres.DB -> TestTree
317335testAnd = databasePropertyTest "AND (&&.)" \transaction -> do
318336 (x, y) <- forAll $ liftA2 (,) Gen.bool Gen.bool
319337
320− transaction \connection -> do
321− [result] <- liftIO $ Rel8.select connection $ pure $
322− Rel8.lit x Rel8.&&. Rel8.lit y
338+ transaction do
339+ [result] <- lift do
340+ statement () $ Rel8.select do
341+ pure $ Rel8.lit x Rel8.&&. Rel8.lit y
323342
324343 result === (x && y)
325344
@@ -328,9 +347,10 @@ testOr :: IO TmpPostgres.DB -> TestTree
328347testOr = databasePropertyTest "OR (||.)" \transaction -> do
329348 (x, y) <- forAll $ liftA2 (,) Gen.bool Gen.bool
330349
331− transaction \connection -> do
332− [result] <- liftIO $ Rel8.select connection $ pure $
333− Rel8.lit x Rel8.||. Rel8.lit y
350+ transaction do
351+ [result] <- lift do
352+ statement () $ Rel8.select $ pure $
353+ Rel8.lit x Rel8.||. Rel8.lit y
334354
335355 result === (x || y)
336356
@@ -339,9 +359,10 @@ testLogicalFixities :: IO TmpPostgres.DB -> TestTree
339359testLogicalFixities = databasePropertyTest "Logical operator fixities" \transaction -> do
340360 (u, v, w, x) <- forAll $ (,,,) <$> Gen.bool <*> Gen.bool <*> Gen.bool <*> Gen.bool
341361
342− transaction \connection -> do
343− [result] <- liftIO $ Rel8.select connection $ pure $
344− Rel8.lit u Rel8.||. Rel8.lit v Rel8.&&. Rel8.lit w Rel8.==. Rel8.lit x
362+ transaction do
363+ [result] <- lift do
364+ statement () $ Rel8.select do
365+ pure $ Rel8.lit u Rel8.||. Rel8.lit v Rel8.&&. Rel8.lit w Rel8.==. Rel8.lit x
345366
346367 result === (u || v && w == x)
347368
@@ -350,9 +371,10 @@ testNot :: IO TmpPostgres.DB -> TestTree
350371testNot = databasePropertyTest "NOT (not_)" \transaction -> do
351372 x <- forAll Gen.bool
352373
353− transaction \connection -> do
354− [result] <- liftIO $ Rel8.select connection $ pure $
355− Rel8.not_ $ Rel8.lit x
374+ transaction do
375+ [result] <- lift do
376+ statement () $ Rel8.select do
377+ pure $ Rel8.not_ $ Rel8.lit x
356378
357379 result === not x
358380
@@ -361,9 +383,10 @@ testBool :: IO TmpPostgres.DB -> TestTree
361383testBool = databasePropertyTest "ifThenElse_" \transaction -> do
362384 (x, y, z) <- forAll $ liftA3 (,,) Gen.bool Gen.bool Gen.bool
363385
364− transaction \connection -> do
365− [result] <- liftIO $ Rel8.select connection $ pure $
366− Rel8.bool (Rel8.lit z) (Rel8.lit y) (Rel8.lit x)
386+ transaction do
387+ [result] <- lift do
388+ statement () $ Rel8.select do
389+ pure $ Rel8.bool (Rel8.lit z) (Rel8.lit y) (Rel8.lit x)
367390
368391 result === if x then y else z
369392
@@ -375,9 +398,10 @@ testAp = databasePropertyTest "Cartesian product (<*>)" \transaction -> do
375398 (Gen.list (Range.linear 1 10) genTestTable)
376399 (Gen.list (Range.linear 1 10) genTestTable)
377400
378− transaction \connection -> do
379− result <- liftIO $ Rel8.select connection $ do
380− liftA2 (,) (Rel8.values (Rel8.lit <$> rows1)) (Rel8.values (Rel8.lit <$> rows2))
401+ transaction do
402+ result <- lift do
403+ statement () $ Rel8.select do
404+ liftA2 (,) (Rel8.values (Rel8.lit <$> rows1)) (Rel8.values (Rel8.lit <$> rows2))
381405
382406 sort result === sort (liftA2 (,) rows1 rows2)
383407
@@ -406,21 +430,22 @@ testDBType getTestDatabase = testGroup "DBType instances"
406430 where
407431 dbTypeTest :: (Eq a, Show a, Rel8.DBType a) => TestName -> Gen a -> TestTree
408432 dbTypeTest name generator = testGroup name
409− [ databasePropertyTest name (t (==) generator) getTestDatabase
410− , databasePropertyTest ("Maybe " <> name) (t (==) (Gen.maybe generator)) getTestDatabase
433+ [ databasePropertyTest name (t generator) getTestDatabase
434+ , databasePropertyTest ("Maybe " <> name) (t (Gen.maybe generator)) getTestDatabase
411435 ]
412436
413− t :: forall a b. (Show a, Rel8.Sql Rel8.DBType a)
414− => (a -> a -> Bool)
415− -> Gen a
416− -> ((Connection -> TestT IO ()) -> PropertyT IO b)
437+ t :: forall a b. (Eq a, Show a, Rel8.Sql Rel8.DBType a)
438+ => Gen a
439+ -> (TestT Transaction () -> PropertyT IO b)
417440 -> PropertyT IO b
418− t eq generator transaction = do
441+ t generator transaction = do
419442 x <- forAll generator
420443
421− transaction \connection -> do
422− [res] <- liftIO $ Rel8.select connection $ pure (Rel8.litExpr x)
423− diff res eq x
444+ transaction do
445+ [res] <- lift do
446+ statement () $ Rel8.select do
447+ pure (Rel8.litExpr x)
448+ diff res (==) x
424449
425450 genDay :: Gen Day
426451 genDay = do
@@ -462,39 +487,38 @@ testDBEq getTestDatabase = testGroup "DBEq instances"
462487
463488 t :: forall a. (Eq a, Show a, Rel8.Sql Rel8.DBEq a)
464489 => Gen a
465− -> ((Connection -> TestT IO ()) -> PropertyT IO ())
490+ -> (TestT Transaction () -> PropertyT IO ())
466491 -> PropertyT IO ()
467492 t generator transaction = do
468493 (x, y) <- forAll (liftA2 (,) generator generator)
469494
470− transaction \connection -> do
471− [res] <- liftIO $ Rel8.select connection $ pure $ Rel8.litExpr x Rel8.==. Rel8.litExpr y
495+ transaction do
496+ [res] <- lift do
497+ statement () $ Rel8.select do
498+ pure $ Rel8.litExpr x Rel8.==. Rel8.litExpr y
472499 res === (x == y)
473500
474− cover 1 "Equal" $ x == y
475− cover 1 "Not Equal" $ x /= y
476−
477501
478502testTableEquality :: IO TmpPostgres.DB -> TestTree
479503testTableEquality = databasePropertyTest "TestTable equality" \transaction -> do
480504 (x, y) <- forAll $ liftA2 (,) genTestTable genTestTable
481505
482− transaction \connection -> do
483− [eq] <- liftIO $ Rel8.select connection do
484− pure $ Rel8.lit x Rel8.==: Rel8.lit y
506+ transaction do
507+ [eq] <- lift do
508+ statement () $ Rel8.select do
509+ pure $ Rel8.lit x Rel8.==: Rel8.lit y
485510
486511 eq === (x == y)
487512
488− cover 1 "Equal" $ x == y
489− cover 1 "Not Equal" $ x /= y
490−
491513
492514testFromString :: IO TmpPostgres.DB -> TestTree
493515testFromString = databasePropertyTest "FromString" \transaction -> do
494516 str <- forAll $ Gen.list (Range.linear 0 10) Gen.unicode
495517
496− transaction \connection -> do
497− [result] <- liftIO $ Rel8.select connection $ pure $ fromString str
518+ transaction do
519+ [result] <- lift do
520+ statement () $ Rel8.select do
521+ pure $ fromString str
498522 result === pack str
499523
500524
@@ -502,10 +526,11 @@ testCatMaybeTable :: IO TmpPostgres.DB -> TestTree
502526testCatMaybeTable = databasePropertyTest "catMaybeTable" \transaction -> do
503527 rows <- forAll $ Gen.list (Range.linear 0 10) genTestTable
504528
505− transaction \connection -> do
506− selected <- liftIO $ Rel8.select connection do
507− testTable <- Rel8.values $ Rel8.lit <$> rows
508− Rel8.catMaybeTable $ Rel8.bool Rel8.nothingTable (pure testTable) (testTableColumn2 testTable)
529+ transaction do
530+ selected <- lift do
531+ statement () $ Rel8.select do
532+ testTable <- Rel8.values $ Rel8.lit <$> rows
533+ Rel8.catMaybeTable $ Rel8.bool Rel8.nothingTable (pure testTable) (testTableColumn2 testTable)
509534
510535 sort selected === sort (filter testTableColumn2 rows)
511536
@@ -514,9 +539,10 @@ testCatMaybe :: IO TmpPostgres.DB -> TestTree
514539testCatMaybe = databasePropertyTest "catMaybe" \transaction -> evalM do
515540 rows <- forAll $ Gen.list (Range.linear 0 10) $ Gen.maybe Gen.bool
516541
517− transaction \connection -> do
518− selected <- evalM $ liftIO $ Rel8.select connection do
519− Rel8.catNull =<< Rel8.values (map Rel8.lit rows)
542+ transaction do
543+ selected <- lift do
544+ statement () $ Rel8.select do
545+ Rel8.catNull =<< Rel8.values (map Rel8.lit rows)
520546
521547 sort selected === sort (catMaybes rows)
522548
@@ -525,21 +551,44 @@ testMaybeTable :: IO TmpPostgres.DB -> TestTree
525551testMaybeTable = databasePropertyTest "maybeTable" \transaction -> evalM do
526552 (rows, def) <- forAll $ liftA2 (,) (Gen.list (Range.linear 0 10) genTestTable) genTestTable
527553
528− transaction \connection -> do
529− selected <- liftIO $ Rel8.select connection $
530− Rel8.maybeTable (Rel8.lit def) id <$> Rel8.optional (Rel8.values (Rel8.lit <$> rows))
554+ transaction do
555+ selected <- lift do
556+ statement () $ Rel8.select do
557+ Rel8.maybeTable (Rel8.lit def) id <$> Rel8.optional (Rel8.values (Rel8.lit <$> rows))
531558
532559 case rows of
533560 [] -> selected === [def]
534561 _ -> sort selected === sort rows
535562
536563
564+testAggregateMaybeTable :: IO TmpPostgres.DB -> TestTree
565+testAggregateMaybeTable = databasePropertyTest "aggregateMaybeTable" \transaction -> evalM do
566+ rows <- forAll $ Gen.list (Range.linear 0 10) (Gen.maybe (Gen.int64 (Range.linear 0 10)))
567+
568+ let
569+ aggregate = go 0 False False
570+ where
571+ go !n nothing _ (Just a : as) = go (n + a) nothing True as
572+ go n _ just (Nothing : as) = go n True just as
573+ go _ False False [] = []
574+ go _ True False [] = [Nothing]
575+ go n False True [] = [Just n]
576+ go n True True [] = [Nothing, Just n]
577+
578+ transaction do
579+ selected <- lift do
580+ statement () $ Rel8.select do
581+ Rel8.aggregate $ Rel8.aggregateMaybeTable Rel8.sum <$> Rel8.values (Rel8.lit <$> rows)
582+
583+ sort selected === aggregate rows
584+
585+
537586data TwoTestTables f =
538587 TwoTestTables
539588 { testTable1 :: TestTable f
540589 , testTable2 :: TestTable f
541590 }
542− deriving stock Generic
591+ deriving stock Generic
543592 deriving anyclass Rel8.Rel8able
544593
545594
@@ -554,9 +603,10 @@ testNestedTables = databasePropertyTest "Nested TestTables" \transaction -> eval
554603 Gen.list (Range.linear 0 10) $
555604 liftA2 TwoTestTables genTestTable genTestTable
556605
557− transaction \connection -> do
558− selected <- liftIO $ Rel8.select connection do
559− Rel8.values (Rel8.lit <$> rows)
606+ transaction do
607+ selected <- lift do
608+ statement () $ Rel8.select do
609+ Rel8.values (Rel8.lit <$> rows)
560610
561611 sort selected === sort rows
562612
@@ -566,11 +616,12 @@ testMaybeTableApplicative = databasePropertyTest "MaybeTable (<*>)" \transaction
566616 rows1 <- genRows
567617 rows2 <- genRows
568618
569− transaction \connection -> do
570− selected <- liftIO $ Rel8.select connection do
571− as <- Rel8.optional (Rel8.values (Rel8.lit <$> rows1))
572− bs <- Rel8.optional (Rel8.values (Rel8.lit <$> rows2))
573− pure $ liftA2 (,) as bs
619+ transaction do
620+ selected <- lift do
621+ statement () $ Rel8.select do
622+ as <- Rel8.optional (Rel8.values (Rel8.lit <$> rows1))
623+ bs <- Rel8.optional (Rel8.values (Rel8.lit <$> rows2))
624+ pure $ liftA2 (,) as bs
574625
575626 case (rows1, rows2) of
576627 ([], []) -> selected === [Nothing]
@@ -582,14 +633,6 @@ testMaybeTableApplicative = databasePropertyTest "MaybeTable (<*>)" \transaction
582633 genRows = forAll do
583634 Gen.list (Range.linear 0 10) $ liftA2 TestTable (Gen.text (Range.linear 0 10) Gen.unicode) (pure True)
584635
585−rollingBack
586− :: (MonadBaseControl IO m, MonadIO m)
587− => Connection -> m a -> m a
588−rollingBack connection =
589− bracket_
590− (liftIO (run (sql "BEGIN") connection))
591− (liftIO (run (sql "ROLLBACK") connection))
592−
593636
594637genTestTable :: Gen (TestTable Result)
595638genTestTable = do
@@ -602,19 +645,19 @@ testUpdate :: IO TmpPostgres.DB -> TestTree
602645testUpdate = databasePropertyTest "Can UPDATE TestTable" \transaction -> do
603646 rows <- forAll $ Gen.map (Range.linear 0 5) $ liftA2 (,) genTestTable genTestTable
604647
605− transaction \connection -> do
606− void $ liftIO $ Rel8.insert connection
607− Rel8.Insert
648+ transaction do
649+ selected <- lift do
650+ statement () $ Rel8.insert Rel8.Insert
608651 { into = testTableSchema
609− , rows = map (Rel8.toInsert . Rel8.lit) $ Map.keys rows
652+ , rows = Rel8.values $ map Rel8.lit $ Map.keys rows
610653 , onConflict = Rel8.DoNothing
611− , returning = Rel8.NumberOfRowsAffected
654+ , returning = pure ()
612655 }
613656
614− void $ liftIO $ Rel8.update connection
615− Rel8.Update
657+ statement () $ Rel8.update Rel8.Update
616658 { target = testTableSchema
617− , set = \r ->
659+ , from = pure ()
660+ , set = \_ r ->
618661 let updates = map (bimap Rel8.lit Rel8.lit) $ Map.toList rows
619662 in
620663 foldl
@@ -628,12 +671,12 @@ testUpdate = databasePropertyTest "Can UPDATE TestTable" \transaction -> do
628671 )
629672 r
630673 updates
631− , updateWhere = \_ -> Rel8.lit True
632− , returning = Rel8.NumberOfRowsAffected
674+ , updateWhere = \_ _ -> Rel8.lit True
675+ , returning = pure ()
633676 }
634677
635− selected <- liftIO $ Rel8.select connection do
636− Rel8.each testTableSchema
678+ statement () $ Rel8.select do
679+ Rel8.each testTableSchema
637680
638681 sort selected === sort (Map.elems rows)
639682
@@ -646,29 +689,96 @@ testDelete :: IO TmpPostgres.DB -> TestTree
646689testDelete = databasePropertyTest "Can DELETE TestTable" \transaction -> do
647690 rows <- forAll $ Gen.list (Range.linear 0 5) genTestTable
648691
649− transaction \connection -> do
650− void $ liftIO $ Rel8.insert connection
651− Rel8.Insert
692+ transaction do
693+ (deleted, selected) <- lift do
694+ statement () $ Rel8.insert Rel8.Insert
652695 { into = testTableSchema
653− , rows = map (Rel8.toInsert . Rel8.lit) rows
696+ , rows = Rel8.values $ map Rel8.lit rows
654697 , onConflict = Rel8.DoNothing
655− , returning = Rel8.NumberOfRowsAffected
698+ , returning = pure ()
656699 }
657700
658− deleted <-
659− liftIO $ Rel8.delete connection
660− Rel8.Delete
701+ deleted <- statement () $ Rel8.delete Rel8.Delete
661702 { from = testTableSchema
662− , deleteWhere = testTableColumn2
703+ , using = pure ()
704+ , deleteWhere = const testTableColumn2
663705 , returning = Rel8.Projection id
664706 }
665707
666− selected <- liftIO $ Rel8.select connection do
667− Rel8.each testTableSchema
708+ selected <- statement () $ Rel8.select do
709+ Rel8.each testTableSchema
710+
711+ pure (deleted, selected)
668712
669713 sort (deleted <> selected) === sort rows
670714
671715
716+data UniqueTable f = UniqueTable
717+ { uniqueTableKey :: Rel8.Column f Text
718+ , uniqueTableValue :: Rel8.Column f Text
719+ }
720+ deriving stock Generic
721+ deriving anyclass Rel8.Rel8able
722+
723+
724+deriving stock instance Eq (UniqueTable Result)
725+deriving stock instance Ord (UniqueTable Result)
726+deriving stock instance Show (UniqueTable Result)
727+
728+
729+uniqueTableSchema :: Rel8.TableSchema (UniqueTable Rel8.Name)
730+uniqueTableSchema =
731+ Rel8.TableSchema
732+ { name = "unique_table"
733+ , schema = Nothing
734+ , columns = UniqueTable
735+ { uniqueTableKey = "key"
736+ , uniqueTableValue = "value"
737+ }
738+ }
739+
740+
741+genUniqueTable :: Gen (UniqueTable Result)
742+genUniqueTable = do
743+ uniqueTableKey <- Gen.text (Range.linear 0 5) Gen.alphaNum
744+ uniqueTableValue <- Gen.text (Range.linear 0 5) Gen.alphaNum
745+ pure UniqueTable {..}
746+
747+
748+testUpsert :: IO TmpPostgres.DB -> TestTree
749+testUpsert = databasePropertyTest "Can UPSERT UniqueTable" \transaction -> do
750+ as <- unique $ forAll $ Gen.list (Range.linear 0 20) genUniqueTable
751+ bs <- unique $ forAll $ Gen.list (Range.linear 0 20) genUniqueTable
752+
753+ transaction do
754+ selected <- lift do
755+ statement () $ Rel8.insert Rel8.Insert
756+ { into = uniqueTableSchema
757+ , rows = Rel8.values $ Rel8.lit <$> as
758+ , onConflict = Rel8.DoNothing
759+ , returning = pure ()
760+ }
761+
762+ statement () $ Rel8.insert Rel8.Insert
763+ { into = uniqueTableSchema
764+ , rows = Rel8.values $ Rel8.lit <$> bs
765+ , onConflict = Rel8.DoUpdate Rel8.Upsert
766+ { index = uniqueTableKey
767+ , set = \UniqueTable {uniqueTableValue} old -> old {uniqueTableValue}
768+ , updateWhere = \_ _ -> Rel8.true
769+ }
770+ , returning = pure ()
771+ }
772+
773+ statement () $ Rel8.select do
774+ Rel8.each uniqueTableSchema
775+
776+ fromUniqueTables selected === fromUniqueTables bs <> fromUniqueTables as
777+ where
778+ unique = fmap (nubOrdOn uniqueTableKey)
779+ fromUniqueTables = Map.fromList . map \(UniqueTable key value) -> (key, value)
780+
781+
672782newtype HKNestedPair f = HKNestedPair { pairOne :: (TestTable f, TestTable f) }
673783 deriving stock Generic
674784 deriving anyclass Rel8.Rel8able
@@ -682,9 +792,10 @@ testSelectNestedPairs :: IO TmpPostgres.DB -> TestTree
682792testSelectNestedPairs = databasePropertyTest "Can SELECT nested pairs" \transaction -> do
683793 rows <- forAll $ Gen.list (Range.linear 0 10) $ HKNestedPair <$> liftA2 (,) genTestTable genTestTable
684794
685− transaction \connection -> do
686− selected <- liftIO $ Rel8.select connection do
687− Rel8.values $ map Rel8.lit rows
795+ transaction do
796+ selected <- lift do
797+ statement () $ Rel8.select do
798+ Rel8.values $ map Rel8.lit rows
688799
689800 sort selected === sort rows
690801
@@ -693,12 +804,23 @@ testSelectArray :: IO TmpPostgres.DB -> TestTree
693804testSelectArray = databasePropertyTest "Can SELECT Arrays (with aggregation)" \transaction -> do
694805 rows <- forAll $ Gen.list (Range.linear 1 10) Gen.bool
695806
696− transaction \connection -> do
697− selected <- liftIO $ Rel8.select connection $ Rel8.aggregate do
698− Rel8.listAgg <$> Rel8.values (map Rel8.lit rows)
807+ transaction do
808+ selected <- lift do
809+ statement () $ Rel8.select do
810+ Rel8.many $ Rel8.values (map Rel8.lit rows)
699811
700812 selected === [foldMap pure rows]
701813
814+ selected' <- lift do
815+ statement () $ Rel8.select do
816+ a <- Rel8.catListTable =<< do
817+ Rel8.many $ Rel8.values (map Rel8.lit rows)
818+ b <- Rel8.catListTable =<< do
819+ Rel8.many $ Rel8.values (map Rel8.lit rows)
820+ pure (a, b)
821+
822+ selected' === liftA2 (,) rows rows
823+
702824
703825data NestedMaybeTable f = NestedMaybeTable
704826 { nmt1 :: Rel8.Column f Bool
@@ -717,9 +839,51 @@ testNestedMaybeTable :: IO TmpPostgres.DB -> TestTree
717839testNestedMaybeTable = databasePropertyTest "Can nest MaybeTable within other tables" \transaction -> do
718840 let example = NestedMaybeTable { nmt1 = True, nmt2 = Just (TestTable "Hi" True) }
719841
720− transaction \connection -> do
721− selected <- liftIO $ Rel8.select connection do
722− x <- Rel8.values [Rel8.lit example]
723− pure $ Rel8.maybeTable (Rel8.lit False) (\_ -> Rel8.lit True) (nmt2 x)
842+ transaction do
843+ selected <- lift do
844+ statement () $ Rel8.select do
845+ x <- Rel8.values [Rel8.lit example]
846+ pure $ Rel8.maybeTable (Rel8.lit False) (\_ -> Rel8.lit True) (nmt2 x)
724847
725848 selected === [True]
849+
850+
851+testEvaluate :: IO TmpPostgres.DB -> TestTree
852+testEvaluate = databasePropertyTest "evaluate has the evaluation order we expect" \transaction -> do
853+
854+ transaction do
855+ selected <- lift do
856+ statement () $ Rel8.select do
857+ x <- Rel8.values (Rel8.lit <$> ['a', 'b', 'c'])
858+ y <- Rel8.evaluate (Rel8.nextval "test_seq")
859+ pure (x, (y, y))
860+
861+ normalize selected ===
862+ [ ('a', (0, 0))
863+ , ('b', (1, 1))
864+ , ('c', (2, 2))
865+ ]
866+
867+ selected' <- lift do
868+ statement () $ Rel8.select do
869+ x <- Rel8.values (Rel8.lit <$> ['a', 'b', 'c'])
870+ y <- Rel8.values (Rel8.lit <$> ['d', 'e', 'f'])
871+ z <- Rel8.evaluate (Rel8.nextval "test_seq")
872+ pure ((x, y), (z, z))
873+
874+ normalize selected' ===
875+ [ (('a', 'd'), (0, 0))
876+ , (('a', 'e'), (1, 1))
877+ , (('a', 'f'), (2, 2))
878+ , (('b', 'd'), (3, 3))
879+ , (('b', 'e'), (4, 4))
880+ , (('b', 'f'), (5, 5))
881+ , (('c', 'd'), (6, 6))
882+ , (('c', 'e'), (7, 7))
883+ , (('c', 'f'), (8, 8))
884+ ]
885+
886+ where
887+ normalize :: [(x, (Int64, Int64))] -> [(x, (Int64, Int64))]
888+ normalize [] = []
889+ normalize xs@((_, (i, _)) : _) = map (fmap (\(a, b) -> (a - i, b - i))) xs
src/Rel8/Schema/Generic/Test.hs → tests/Rel8/Generic/Rel8able/Test.hsrenamed+87−14
@@ -1,15 +1,18 @@
11{-# language DataKinds #-}
22{-# language DeriveAnyClass #-}
33{-# language DeriveGeneric #-}
4−{-# language DerivingVia #-}
4+{-# language DerivingStrategies #-}
55{-# language DuplicateRecordFields #-}
66{-# language FlexibleInstances #-}
77{-# language MultiParamTypeClasses #-}
8−{-# language StandaloneDeriving #-}
8+{-# language StandaloneKindSignatures #-}
99{-# language TypeFamilies #-}
10+{-# language UndecidableInstances #-}
1011
11−module Rel8.Schema.Generic.Test
12− ( module Rel8.Schema.Generic.Test
12+{-# options_ghc -O0 #-}
13+
14+module Rel8.Generic.Rel8able.Test
15+ ( module Rel8.Generic.Rel8able.Test
1316 )
1417where
1518
@@ -17,9 +20,6 @@ where
1720import GHC.Generics ( Generic )
1821import Prelude
1922
20−-- higgledy
21−import Data.Generic.HKD ( HKD )
22−
2323-- rel8
2424import Rel8
2525
@@ -27,7 +27,7 @@ import Rel8
2727import Data.Text ( Text )
2828
2929
30−data Table f = Table
30+data TableTest f = TableTest
3131 { foo :: Column f Bool
3232 , bar :: Column f (Maybe Bool)
3333 }
@@ -36,7 +36,7 @@ data Table f = Table
3636
3737
3838data TablePair f = TablePair
39− { foo :: Default f Bool
39+ { foo :: Column f Bool
4040 , bars :: (Column f Text, Column f Text)
4141 }
4242 deriving stock Generic
@@ -77,7 +77,15 @@ data TableList f = TableList
7777
7878data TableNonEmpty f = TableNonEmpty
7979 { foo :: Column f Bool
80− , bars :: HNonEmpty f (TableList f, Default f Char)
80+ , bars :: HNonEmpty f (TableList f, TableMaybe f)
81+ }
82+ deriving stock Generic
83+ deriving anyclass Rel8able
84+
85+
86+data TableNest f = TableNest
87+ { foo :: Column f Bool
88+ , bars :: HList f (HMaybe f (TablePair f))
8189 }
8290 deriving stock Generic
8391 deriving anyclass Rel8able
@@ -86,16 +94,24 @@ data TableNonEmpty f = TableNonEmpty
8694data S3Object = S3Object
8795 { bucketName :: Text
8896 , objectKey :: Text
89− } deriving stock Generic
97+ }
98+ deriving stock Generic
99+
90100
101+instance x ~ HKD S3Object Expr => ToExprs x S3Object
91102
92−deriving via HKDT S3Object
93− instance x ~ HKD S3Object Expr => ToExprs x S3Object
103+
104+data HKDSum = HKDSumA Text | HKDSumB Bool Char | HKDSumC
105+ deriving stock Generic
106+
107+
108+instance x ~ HKD HKDSum Expr => ToExprs x HKDSum
94109
95110
96111data HKDTest f = HKDTest
97112 { s3Object :: Lift f S3Object
98− }
113+ , hkdSum :: Lift f HKDSum
114+ }
99115 deriving stock Generic
100116 deriving anyclass Rel8able
101117
@@ -113,3 +129,60 @@ data NonRecord f = NonRecord
113129 (Column f Char)
114130 deriving stock Generic
115131 deriving anyclass Rel8able
132+
133+
134+data TableSum f
135+ = TableSumA (Column f Bool) (Column f Text)
136+ | TableSumB
137+ | TableSumC (Column f Text)
138+ deriving stock Generic
139+
140+
141+data BarbieSum f
142+ = BarbieSumA (f Bool) (f Text)
143+ | BarbieSumB
144+ | BarbieSumC (f Text)
145+ deriving stock Generic
146+
147+
148+data TableProduct f = TableProduct
149+ { sum :: HADT f BarbieSum
150+ , list :: TableList f
151+ , foos :: HList f (HADT f TableSum, Lift f HKDSum, HKDTest f)
152+ }
153+ deriving stock Generic
154+ deriving anyclass Rel8able
155+
156+
157+data TableTestB f = TableTestB
158+ { foo :: f Bool
159+ , bar :: f (Maybe Bool)
160+ }
161+ deriving stock Generic
162+ deriving anyclass Rel8able
163+
164+
165+data NestedTableTestB f = NestedTableTestB
166+ { foo :: f Bool
167+ , bar :: f (Maybe Bool)
168+ , baz :: Column f Char
169+ , nest :: TableTestB f
170+ }
171+ deriving stock Generic
172+ deriving anyclass Rel8able
173+
174+
175+newtype IdRecord a f = IdRecord { recordId :: Column f a }
176+ deriving stock Generic
177+
178+
179+instance DBType a => Rel8able (IdRecord a)
180+
181+
182+type Nest :: KRel8able -> KRel8able -> KRel8able
183+data Nest t u f = Nest
184+ { foo :: t f
185+ , bar :: u f
186+ }
187+ deriving stock Generic
188+ deriving anyclass Rel8able