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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+48−18 shell.nix+1−1 src/Rel8.hs+319−33 src/Rel8/Aggregate.hs+37−109 src/Rel8/Column.hs+5−77 src/Rel8/Column/ADT.hs+3−68 src/Rel8/Column/Either.hs+4−140 src/Rel8/Column/Lift.hs+3−67 src/Rel8/Column/List.hs+6−126 src/Rel8/Column/Maybe.hs+4−105 src/Rel8/Column/NonEmpty.hs+6−127 src/Rel8/Column/Null.hs+26 src/Rel8/Column/These.hs+5−142 src/Rel8/Expr.hs+17−47 src/Rel8/Expr.hs-boot+6−8 src/Rel8/Expr/Aggregate.hs+25−64 src/Rel8/Expr/Default.hs+35 src/Rel8/Expr/Eq.hs+1−1 src/Rel8/Expr/Num.hs+39−6 src/Rel8/Expr/Opaleye.hs+12−3 src/Rel8/Expr/Sequence.hs+2−1 src/Rel8/Expr/Text.hs+23−2 src/Rel8/Expr/Window.hs+121 src/Rel8/FCF.hs+3−3 src/Rel8/Generic/Construction.hs+146−165 src/Rel8/Generic/Construction/ADT.hs+32−47 src/Rel8/Generic/Construction/Record.hs+6−11 src/Rel8/Generic/Map.hs+20−64 src/Rel8/Generic/Record.hs+2 src/Rel8/Generic/Reify.hs−24 src/Rel8/Generic/Rel8able.hs+178−72 src/Rel8/Generic/Table.hs+24−109 src/Rel8/Generic/Table/ADT.hs+61−203 src/Rel8/Generic/Table/Record.hs+74−99 src/Rel8/Kind/Context.hs+8−33 src/Rel8/Kind/Labels.hs−57 src/Rel8/Order.hs+2−9 src/Rel8/Query.hs+181−7 src/Rel8/Query.hs-boot+3−1 src/Rel8/Query/Aggregate.hs+19 src/Rel8/Query/Distinct.hs+4−9 src/Rel8/Query/Each.hs+3−3 src/Rel8/Query/Either.hs+9−21 src/Rel8/Query/Evaluate.hs+28−61 src/Rel8/Query/Exists.hs+14−16 src/Rel8/Query/Indexed.hs+21 src/Rel8/Query/List.hs+19−15 src/Rel8/Query/Maybe.hs+24−44 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+52−46 src/Rel8/Query/Window.hs+26 src/Rel8/Schema/Context.hs−20 src/Rel8/Schema/Context/Label.hs−62 src/Rel8/Schema/Context/Nullify.hs+105−149 src/Rel8/Schema/Field.hs+50 src/Rel8/Schema/HTable.hs+51−24 src/Rel8/Schema/HTable/Either.hs+2−3 src/Rel8/Schema/HTable/Identity.hs+16−28 src/Rel8/Schema/HTable/Label.hs+37−50 src/Rel8/Schema/HTable/MapTable.hs+22−12 src/Rel8/Schema/HTable/Maybe.hs+2−3 src/Rel8/Schema/HTable/Nullify.hs+47−32 src/Rel8/Schema/HTable/These.hs+2−3 src/Rel8/Schema/HTable/Vectorize.hs+37−45 src/Rel8/Schema/Kind.hs+6−15 src/Rel8/Schema/Name.hs+34−56 src/Rel8/Schema/Reify.hs−74 src/Rel8/Schema/Result.hs+16−41 src/Rel8/Schema/Spec.hs+17−37 src/Rel8/Schema/Spec/ConstrainDBType.hs−89 src/Rel8/Schema/Table.hs+20 src/Rel8/Statement/Delete.hs+35−48 src/Rel8/Statement/Insert.hs+43−72 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+38−56 src/Rel8/Statement/Using.hs+36 src/Rel8/Statement/View.hs+43−28 src/Rel8/Statement/Where.hs+31 src/Rel8/Table.hs+88−252 src/Rel8/Table/ADT.hs+33−65 src/Rel8/Table/Aggregate.hs+24−13 src/Rel8/Table/Bool.hs+5−6 src/Rel8/Table/Cols.hs+50 src/Rel8/Table/Either.hs+126−131 src/Rel8/Table/Eq.hs+12−39 src/Rel8/Table/HKD.hs+65−105 src/Rel8/Table/List.hs+65−55 src/Rel8/Table/Maybe.hs+111−120 src/Rel8/Table/Name.hs+17−22 src/Rel8/Table/NonEmpty.hs+66−54 src/Rel8/Table/Null.hs+147 src/Rel8/Table/Nullify.hs+211 src/Rel8/Table/Opaleye.hs+78−64 src/Rel8/Table/Ord.hs+16−45 src/Rel8/Table/Order.hs+13−16 src/Rel8/Table/Projection.hs+73 src/Rel8/Table/Recontextualize.hs−90 src/Rel8/Table/Rel8able.hs+29−85 src/Rel8/Table/Serialize.hs+22−122 src/Rel8/Table/Tag.hs−97 src/Rel8/Table/These.hs+164−148 src/Rel8/Table/Transpose.hs+46 src/Rel8/Table/Undefined.hs+5−5 src/Rel8/Table/Unreify.hs−102 src/Rel8/Table/Window.hs+43 src/Rel8/Tabulate.hs+640 src/Rel8/Type.hs+9−8 src/Rel8/Type/Composite.hs+20−19 src/Rel8/Type/Enum.hs+1 src/Rel8/Type/JSONBEncoded.hs+4 src/Rel8/Type/JSONEncoded.hs+4 src/Rel8/Type/Num.hs+4−1 src/Rel8/Type/Ord.hs−2 src/Rel8/Type/ReadShow.hs+3 src/Rel8/Type/Tag.hs+2−1 src/Rel8/Window.hs+97 tests/Main.hs+320−161 src/Rel8/Generic/Rel8able/Test.hs → tests/Rel8/Generic/Rel8able/Test.hs+47−16
.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+48−18
@@ -1,38 +1,52 @@
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
27+ , comonad
1728 , contravariant
18− , hasql ^>= 1.4.5.1
19− , 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
2032 , profunctors
33+ , product-profunctors
2134 , scientific
2235 , semialign
2336 , semigroupoids
2437 , text
2538 , these
2639 , time
27− , transformers
2840 , uuid
2941 default-language:
3042 Haskell2010
3143 ghc-options:
44+ -Werror=missing-methods -Werror=incomplete-patterns -Werror=missing-fields
3245 -Weverything -Wno-unsafe -Wno-safe -Wno-missing-safe-haskell-mode
3346 -Wno-missing-import-lists -Wno-prepositive-qualified-module
3447 -Wno-monomorphism-restriction
3548 -Wno-missing-local-signatures
49+ -Wno-missing-kind-signatures
3650 hs-source-dirs:
3751 src
3852 exposed-modules:
@@ -40,6 +54,7 @@ library
4054 Rel8.Expr.Num
4155 Rel8.Expr.Text
4256 Rel8.Expr.Time
57+ Rel8.Tabulate
4358
4459 other-modules:
4560 Rel8.Aggregate
@@ -51,12 +66,14 @@ library
5166 Rel8.Column.List
5267 Rel8.Column.Maybe
5368 Rel8.Column.NonEmpty
69+ Rel8.Column.Null
5470 Rel8.Column.These
5571
5672 Rel8.Expr
5773 Rel8.Expr.Aggregate
5874 Rel8.Expr.Array
5975 Rel8.Expr.Bool
76+ Rel8.Expr.Default
6077 Rel8.Expr.Eq
6178 Rel8.Expr.Function
6279 Rel8.Expr.Null
@@ -65,21 +82,19 @@ library
6582 Rel8.Expr.Order
6683 Rel8.Expr.Sequence
6784 Rel8.Expr.Serialize
85+ Rel8.Expr.Window
6886
6987 Rel8.FCF
7088
7189 Rel8.Kind.Algebra
7290 Rel8.Kind.Context
73− Rel8.Kind.Labels
7491
7592 Rel8.Generic.Construction
7693 Rel8.Generic.Construction.ADT
7794 Rel8.Generic.Construction.Record
7895 Rel8.Generic.Map
7996 Rel8.Generic.Record
80− Rel8.Generic.Reify
8197 Rel8.Generic.Rel8able
82− Rel8.Generic.Rel8able.Test
8398 Rel8.Generic.Table
8499 Rel8.Generic.Table.ADT
85100 Rel8.Generic.Table.Record
@@ -94,21 +109,23 @@ library
94109 Rel8.Query.Evaluate
95110 Rel8.Query.Exists
96111 Rel8.Query.Filter
112+ Rel8.Query.Indexed
97113 Rel8.Query.Limit
98114 Rel8.Query.List
99115 Rel8.Query.Maybe
100116 Rel8.Query.Null
101117 Rel8.Query.Opaleye
102118 Rel8.Query.Order
119+ Rel8.Query.Rebind
103120 Rel8.Query.Set
104121 Rel8.Query.SQL
105122 Rel8.Query.These
106123 Rel8.Query.Values
124+ Rel8.Query.Window
107125
108− Rel8.Schema.Context
109− Rel8.Schema.Context.Label
110126 Rel8.Schema.Context.Nullify
111127 Rel8.Schema.Dict
128+ Rel8.Schema.Field
112129 Rel8.Schema.HTable
113130 Rel8.Schema.HTable.Either
114131 Rel8.Schema.HTable.Identity
@@ -124,24 +141,28 @@ library
124141 Rel8.Schema.Kind
125142 Rel8.Schema.Name
126143 Rel8.Schema.Null
127− Rel8.Schema.Reify
128144 Rel8.Schema.Result
129145 Rel8.Schema.Spec
130− Rel8.Schema.Spec.ConstrainDBType
131146 Rel8.Schema.Table
132147
133148 Rel8.Statement.Delete
134149 Rel8.Statement.Insert
150+ Rel8.Statement.OnConflict
135151 Rel8.Statement.Returning
136152 Rel8.Statement.Select
153+ Rel8.Statement.Set
154+ Rel8.Statement.SQL
137155 Rel8.Statement.Update
156+ Rel8.Statement.Using
138157 Rel8.Statement.View
158+ Rel8.Statement.Where
139159
140160 Rel8.Table
141161 Rel8.Table.ADT
142162 Rel8.Table.Aggregate
143163 Rel8.Table.Alternative
144164 Rel8.Table.Bool
165+ Rel8.Table.Cols
145166 Rel8.Table.Either
146167 Rel8.Table.Eq
147168 Rel8.Table.HKD
@@ -149,16 +170,18 @@ library
149170 Rel8.Table.Maybe
150171 Rel8.Table.Name
151172 Rel8.Table.NonEmpty
173+ Rel8.Table.Null
174+ Rel8.Table.Nullify
152175 Rel8.Table.Opaleye
153176 Rel8.Table.Ord
154177 Rel8.Table.Order
155− Rel8.Table.Recontextualize
178+ Rel8.Table.Projection
156179 Rel8.Table.Rel8able
157180 Rel8.Table.Serialize
158− Rel8.Table.Tag
159181 Rel8.Table.These
182+ Rel8.Table.Transpose
160183 Rel8.Table.Undefined
161− Rel8.Table.Unreify
184+ Rel8.Table.Window
162185
163186 Rel8.Type
164187 Rel8.Type.Array
@@ -177,6 +200,9 @@ library
177200 Rel8.Type.Sum
178201 Rel8.Type.Tag
179202
203+ Rel8.Window
204+
205+
180206test-suite tests
181207 type: exitcode-stdio-1.0
182208 build-depends:
@@ -185,9 +211,9 @@ test-suite tests
185211 , case-insensitive
186212 , containers
187213 , hasql
188− , hedgehog ^>=1.0.2
189− , lifted-base ^>=0.2.3.12
190− , monad-control ^>=1.0.2.3
214+ , hasql-transaction
215+ , hedgehog ^>= 1.0 || ^>= 1.1
216+ , mmorph
191217 , rel8
192218 , scientific
193219 , tasty
@@ -195,8 +221,12 @@ test-suite tests
195221 , text
196222 , time
197223 , tmp-postgres ^>=1.34.1.0
224+ , transformers
198225 , uuid
199226
227+ other-modules:
228+ Rel8.Generic.Rel8able.Test
229+
200230 main-is: Main.hs
201231 hs-source-dirs: tests
202232 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+319−33
@@ -38,26 +38,31 @@ module Rel8
3838 , HMaybe
3939 , HList
4040 , HNonEmpty
41+ , HNull
4142 , HThese
4243 , Lift
4344
4445 , Table(..)
46+ , HTable
47+ , Transposes
4548 , AltTable((<|>:))
4649 , AlternativeTable( emptyTable )
47− , EqTable, (==:), (/=:)
48− , OrdTable, ascTable, descTable
50+ , EqTable(..), (==:), (/=:)
51+ , OrdTable(..), (<:), (<=:), (>:), (>=:), ascTable, descTable, greatest, least
4952 , lit
5053 , bool
5154 , case_
55+ , castTable
5256
5357 -- ** @MaybeTable@
5458 , MaybeTable
5559 , maybeTable, ($?), nothingTable, justTable
5660 , isNothingTable, isJustTable
61+ , fromMaybeTable
5762 , optional
5863 , catMaybeTable
59− , bindMaybeTable
6064 , traverseMaybeTable
65+ , aggregateMaybeTable
6166 , nameMaybeTable
6267
6368 -- ** @EitherTable@
@@ -66,8 +71,8 @@ module Rel8
6671 , isLeftTable, isRightTable
6772 , keepLeftTable
6873 , keepRightTable
69− , bindEitherTable
7074 , bitraverseEitherTable
75+ , aggregateEitherTable
7176 , nameEitherTable
7277
7378 -- ** @TheseTable@
@@ -76,19 +81,20 @@ module Rel8
7681 , isThisTable, isThatTable, isThoseTable
7782 , hasHereTable, hasThereTable
7883 , justHereTable, justThereTable
84+ , alignMaybeTable
7985 , alignBy
8086 , keepHereTable, loseHereTable
8187 , keepThereTable, loseThereTable
8288 , keepThisTable, loseThisTable
8389 , keepThatTable, loseThatTable
8490 , keepThoseTable, loseThoseTable
85− , bindTheseTable
8691 , bitraverseTheseTable
92+ , aggregateTheseTable
8793 , nameTheseTable
8894
8995 -- ** @ListTable@
9096 , ListTable
91− , listTable
97+ , listTable, ($*)
9298 , nameListTable
9399 , many
94100 , manyExpr
@@ -97,21 +103,44 @@ module Rel8
97103
98104 -- ** @NonEmptyTable@
99105 , NonEmptyTable
100− , nonEmptyTable
106+ , nonEmptyTable, ($+)
101107 , nameNonEmptyTable
102108 , some
103109 , someExpr
104110 , catNonEmptyTable
105111 , catNonEmpty
106112
107− -- ** @ADT@
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
108127 , ADT, ADTable
128+
129+ -- *** Deconstruction of ADTs
130+ -- $deconstruction
131+ , DeconstructADT, deconstructADT
132+
133+ -- *** Construction of ADTs
134+ -- $construction
109135 , BuildADT, buildADT
110136 , ConstructADT, constructADT
111− , DeconstructADT, deconstructADT
112− , NameADT, nameADT
137+
138+ -- *** Other ADT operations
113139 , AggregateADT, aggregateADT
114140
141+ -- *** Miscellaneous notes
142+ -- $misc-notes
143+
115144 -- ** @HKD@
116145 , HKD, HKDable
117146 , BuildHKD, buildHKD
@@ -134,6 +163,9 @@ module Rel8
134163 , unsafeLiteral
135164
136165 -- ** @null@
166+ , NotNull
167+ , Nullable
168+ , Homonullable
137169 , null
138170 , nullify
139171 , nullable
@@ -152,6 +184,7 @@ module Rel8
152184 , (==.), (/=.), (==?), (/=?)
153185 , in_
154186 , boolExpr, caseExpr
187+ , like, ilike
155188
156189 -- ** Ordering
157190 , DBOrd
@@ -169,6 +202,13 @@ module Rel8
169202 , Query
170203 , showQuery
171204
205+ -- ** Projection
206+ , Projection
207+ , Projectable( project )
208+ , Biprojectable( biproject )
209+ , Projecting
210+ , Field
211+
172212 -- ** Selecting rows
173213 , Selects
174214 , each
@@ -177,8 +217,8 @@ module Rel8
177217 -- ** Filtering
178218 , filter
179219 , where_
180− , whereExists
181− , whereNotExists
220+ , present
221+ , absent
182222 , distinct
183223 , distinctOn
184224 , distinctOnBy
@@ -213,10 +253,11 @@ module Rel8
213253 , countRows
214254 , groupBy
215255 , listAgg, listAggExpr
256+ , mode
216257 , nonEmptyAgg, nonEmptyAggExpr
217258 , DBMax, max
218259 , DBMin, min
219− , DBSum, sum, sumWhere
260+ , DBSum, sum, sumWhere, avg
220261 , DBString, stringAgg
221262 , count
222263 , countStar
@@ -233,52 +274,71 @@ module Rel8
233274 , nullsFirst
234275 , nullsLast
235276
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+
236303 -- * IO
237304 , Serializable
305+ , ToExprs
306+ , Result
238307
239308 -- * Running statements
309+ -- $running
310+
240311 -- ** @SELECT@
241312 , select
242313
243314 -- ** @INSERT@
244315 , Insert(..)
245316 , OnConflict(..)
317+ , Upsert(..)
246318 , insert
319+ , unsafeDefault
320+ , showInsert
247321
248322 -- ** @DELETE@
249323 , Delete(..)
250324 , delete
325+ , showDelete
251326
252327 -- ** @UPDATE@
253− , update
254328 , Update(..)
329+ , update
330+ , showUpdate
255331
256332 -- ** @.. RETURNING@
257333 , Returning(..)
258334
259335 -- ** @CREATE VIEW@
260336 , createView
337+ , createOrReplaceView
261338
262339 -- ** Sequences
263340 , nextval
264−
265− , Evaluate
266− , eval
267341 , evaluate
268−
269− -- * TODO
270− -- TODO
271− -- These need organizing, but are reachable from Rel8's documentation so we
272− -- do need to export and document them.
273− , Recontextualize
274− , Nullable
275− , NotNull
276− , HTable
277− , Labelable
278− , ToExprs(..)
279− , FromExprs
280− , Result
281− , HKDT(..)
282342 ) where
283343
284344-- base
@@ -293,10 +353,12 @@ import Rel8.Column.Lift
293353import Rel8.Column.List
294354import Rel8.Column.Maybe
295355import Rel8.Column.NonEmpty
356+import Rel8.Column.Null
296357import Rel8.Column.These
297358import Rel8.Expr
298359import Rel8.Expr.Aggregate
299360import Rel8.Expr.Bool
361+import Rel8.Expr.Default
300362import Rel8.Expr.Eq
301363import Rel8.Expr.Function
302364import Rel8.Expr.Null
@@ -305,6 +367,8 @@ import Rel8.Expr.Ord
305367import Rel8.Expr.Order
306368import Rel8.Expr.Serialize
307369import Rel8.Expr.Sequence
370+import Rel8.Expr.Text ( like, ilike )
371+import Rel8.Expr.Window hiding ( cumulative )
308372import Rel8.Generic.Rel8able ( KRel8able, Rel8able )
309373import Rel8.Order
310374import Rel8.Query
@@ -315,16 +379,19 @@ import Rel8.Query.Either
315379import Rel8.Query.Evaluate
316380import Rel8.Query.Exists
317381import Rel8.Query.Filter
382+import Rel8.Query.Indexed
318383import Rel8.Query.Limit
319384import Rel8.Query.List
320385import Rel8.Query.Maybe
321386import Rel8.Query.Null
322387import Rel8.Query.Order
388+import Rel8.Query.Rebind
323389import Rel8.Query.SQL (showQuery)
324390import Rel8.Query.Set
325391import Rel8.Query.These
326392import Rel8.Query.Values
327−import Rel8.Schema.Context.Label
393+import Rel8.Query.Window
394+import Rel8.Schema.Field
328395import Rel8.Schema.HTable
329396import Rel8.Schema.Name
330397import Rel8.Schema.Null hiding ( nullable )
@@ -332,8 +399,10 @@ import Rel8.Schema.Result ( Result )
332399import Rel8.Schema.Table
333400import Rel8.Statement.Delete
334401import Rel8.Statement.Insert
402+import Rel8.Statement.OnConflict
335403import Rel8.Statement.Returning
336404import Rel8.Statement.Select
405+import Rel8.Statement.SQL
337406import Rel8.Statement.Update
338407import Rel8.Statement.View
339408import Rel8.Table
@@ -348,12 +417,16 @@ import Rel8.Table.List
348417import Rel8.Table.Maybe
349418import Rel8.Table.Name
350419import Rel8.Table.NonEmpty
420+import Rel8.Table.Null
421+import Rel8.Table.Opaleye ( castTable )
351422import Rel8.Table.Ord
352423import Rel8.Table.Order
353−import Rel8.Table.Recontextualize
424+import Rel8.Table.Projection
354425import Rel8.Table.Rel8able ()
355426import Rel8.Table.Serialize
356427import Rel8.Table.These
428+import Rel8.Table.Transpose
429+import Rel8.Table.Window
357430import Rel8.Type
358431import Rel8.Type.Composite
359432import Rel8.Type.Eq
@@ -368,3 +441,216 @@ import Rel8.Type.ReadShow
368441import Rel8.Type.Semigroup
369442import Rel8.Type.String
370443import 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+37−109
@@ -1,155 +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( A, unA )
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
3432import Rel8.Expr ( Expr )
35−import Rel8.Schema.Context ( Interpretation(..) )
36−import Rel8.Schema.Context.Label ( Labelable(..) )
37−import Rel8.Schema.HTable.Identity ( HIdentity(..), HType )
38−import Rel8.Schema.Name ( Name )
33+import Rel8.Schema.HTable.Identity ( HIdentity(..) )
34+import qualified Rel8.Schema.Kind as K
3935import Rel8.Schema.Null ( Sql )
40−import Rel8.Schema.Reify ( notReify )
41−import Rel8.Schema.Result ( Result )
42−import Rel8.Schema.Spec ( Spec( Spec ) )
4336import Rel8.Table
4437 ( Table, Columns, Context, fromColumns, toColumns
45− , reify, unreify
38+ , FromExprs, fromResult, toResult
39+ , Transpose
4640 )
47−import Rel8.Table.Recontextualize ( Recontextualize )
41+import Rel8.Table.Transpose ( Transposes )
4842import Rel8.Type ( DBType )
4943
5044
51−-- | An @Aggregate a@ describes how to aggregate @Table@s of type @a@. You can
52−-- unpack an @Aggregate@ back to @a@ by running it with 'Rel8.aggregate'. As
53−-- @Aggregate@ is almost an 'Applicative' functor - but there is no 'pure'
54−-- operation. This means 'Aggregate' is an instance of 'Apply', and you can
55−-- combine @Aggregate@s using the @<.>@ combinator.
56−type Aggregate :: k -> Type
57−data Aggregate a where
58− Aggregate :: !(Opaleye.Aggregator () (Expr a)) -> Aggregate a
59−
60−
61−instance Interpretation Aggregate where
62− data Col Aggregate _spec where
63− A :: ()
64− => { unA :: !(Aggregate a) }
65− -> Col Aggregate ('Spec labels a)
45+-- | 'Aggregate' is a special context used by 'Rel8.aggregate'.
46+type Aggregate :: K.Context
47+newtype Aggregate a = Aggregate (Opaleye.Aggregator () (Expr a))
6648
6749
6850instance Sql DBType a => Table Aggregate (Aggregate a) where
69− type Columns (Aggregate a) = HType a
51+ type Columns (Aggregate a) = HIdentity a
7052 type Context (Aggregate a) = Aggregate
53+ type FromExprs (Aggregate a) = a
54+ type Transpose to (Aggregate a) = to a
7155
72− toColumns = HIdentity . A
73− fromColumns (HIdentity (A a)) = a
74−
75− reify = notReify
76− unreify = notReify
77−
78−
79−instance Sql DBType a =>
80− Recontextualize Aggregate Aggregate (Aggregate a) (Aggregate a)
81−
82−
83−instance Sql DBType a =>
84− Recontextualize Aggregate Expr (Aggregate a) (Expr a)
85−
86−
87−instance Sql DBType a =>
88− Recontextualize Aggregate Result (Aggregate a) (Identity a)
89−
90−
91−instance Sql DBType a =>
92− Recontextualize Aggregate Name (Aggregate a) (Name a)
56+ toColumns = HIdentity
57+ fromColumns (HIdentity a) = a
58+ toResult = HIdentity . Identity
59+ fromResult (HIdentity (Identity a)) = a
9360
9461
95−instance Sql DBType a =>
96− Recontextualize Expr Aggregate (Expr a) (Aggregate a)
97−
98−
99−instance Sql DBType a =>
100− Recontextualize Result Aggregate (Identity a) (Aggregate a)
101−
102−
103−instance Sql DBType a =>
104− Recontextualize Name Aggregate (Name a) (Aggregate a)
105−
106−
107−instance Labelable Aggregate where
108− labeler (A aggregate) = A aggregate
109− unlabeler (A aggregate) = A aggregate
110−
111−
112−-- | @Aggregates a b@ means that the columns in @a@ are all 'Aggregate' 'Expr's
113−-- 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@.
11464type Aggregates :: Type -> Type -> Constraint
115−class Recontextualize Aggregate Expr aggregates exprs => Aggregates aggregates exprs
116−instance Recontextualize Aggregate Expr aggregates exprs => Aggregates aggregates exprs
117−
118−
119−foldInputs :: Monoid b
120− => (Maybe Aggregator -> Opaleye.PrimExpr -> b) -> Aggregate a -> b
121−foldInputs f (Aggregate (Opaleye.Aggregator (Opaleye.PackMap agg))) =
122− getConst $ flip agg () $ \(aggregator, a) ->
123− Const $ f (detuplize <$> aggregator) a
124− where
125− detuplize (operation, ordering, distinction) =
126− Aggregator {operation, ordering, distinction}
127−
128−
129−mapInputs :: ()
130− => (Opaleye.PrimExpr -> Opaleye.PrimExpr) -> Aggregate a -> Aggregate a
131−mapInputs transform (Aggregate (Opaleye.Aggregator (Opaleye.PackMap agg))) =
132− Aggregate $ Opaleye.Aggregator $ Opaleye.PackMap $ agg . \f input ->
133− f (fmap transform input)
65+class Transposes Aggregate Expr aggregates exprs => Aggregates aggregates exprs
66+instance Transposes Aggregate Expr aggregates exprs => Aggregates aggregates exprs
13467
13568
136−type Aggregator :: Type
137−data Aggregator = Aggregator
138− { operation :: Opaleye.AggrOp
139− , ordering :: [Opaleye.OrderExpr]
140− , distinction :: Opaleye.AggrDistinct
141− }
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)
14272
14373
144−unsafeMakeAggregate :: ()
74+unsafeMakeAggregate :: forall (input :: Type) (output :: Type) n n' a a'. ()
14575 => (Expr input -> Opaleye.PrimExpr)
14676 -> (Opaleye.PrimExpr -> Expr output)
147− -> Maybe Aggregator
77+ -> Opaleye.Aggregator (Opaleye.Field_ n a) (Opaleye.Field_ n' a')
14878 -> Expr input
14979 -> Aggregate output
15080unsafeMakeAggregate input output aggregator expr =
151− Aggregate $ Opaleye.Aggregator $ Opaleye.PackMap $ \f _ ->
152− output <$> f (tuplize <$> aggregator, input expr)
153− where
154− tuplize Aggregator {operation, ordering, distinction} =
155− (operation, ordering, distinction)
81+ Aggregate $ dimap in_ out aggregator
82+ where out = output . Opaleye.unColumn
83+ in_ = Opaleye.Column . input . const expr
src/Rel8/Column.hs+5−77
@@ -1,38 +1,21 @@
11{-# language DataKinds #-}
2−{-# language FlexibleContexts #-}
3−{-# language LambdaCase #-}
4−{-# language MultiParamTypeClasses #-}
52{-# language StandaloneKindSignatures #-}
63{-# language TypeFamilies #-}
74
85module Rel8.Column
9− ( Column, AColumn(..)
6+ ( Column
107 , TColumn
118 )
129where
1310
1411-- base
1512import Data.Kind ( Type )
16−import Prelude
13+import Prelude ()
1714
1815-- rel8
19−import Rel8.Aggregate ( Aggregate, Col( A ) )
20−import Rel8.Expr ( Expr, Col( E ) )
2116import Rel8.FCF ( Eval, Exp )
22−import Rel8.Kind.Context ( SContext(..), Reifiable( contextSing ) )
23−import Rel8.Schema.HTable.Identity ( HIdentity( HIdentity ) )
2417import qualified Rel8.Schema.Kind as K
25−import Rel8.Schema.Name ( Name(..), Col( N ) )
26−import Rel8.Schema.Null ( Sql )
27−import Rel8.Schema.Reify ( Reify, Col(..) )
28−import Rel8.Schema.Result ( Col( R ), Result )
29−import Rel8.Schema.Spec ( Spec( Spec ) )
30−import Rel8.Table
31− ( Table, Columns, Context, fromColumns, toColumns
32− , Unreify, reify, unreify
33− )
34−import Rel8.Table.Recontextualize ( Recontextualize )
35−import Rel8.Type ( DBType )
18+import Rel8.Schema.Result ( Result )
3619
3720
3821-- | This type family is used to specify columns in 'Rel8able's. In @Column f
@@ -40,63 +23,8 @@ import Rel8.Type ( DBType )
4023-- 'Rel8able' definitions), and @a@ is the type of the column.
4124type Column :: K.Context -> Type -> Type
4225type family Column context a where
43− Column (Reify context) a = AColumn context a
44− Column Aggregate a = Aggregate a
45− Column Expr a = Expr a
46− Column Name a = Name a
47− Column Result a = a
48−
49−
50−type AColumn :: K.Context -> Type -> Type
51−newtype AColumn context a = AColumn (Column context a)
52−
53−
54−instance (Reifiable context, Sql DBType a) =>
55− Table (Reify context) (AColumn context a)
56− where
57− type Context (AColumn context a) = Reify context
58− type Columns (AColumn context a) = HIdentity ('Spec '[] a)
59− type Unreify (AColumn context a) = Column context a
60−
61− fromColumns (HIdentity (Reify a)) = sfromColumn contextSing a
62− toColumns = HIdentity . Reify . stoColumn contextSing
63− reify _ = AColumn
64− unreify _ (AColumn a) = a
65−
66−
67−instance
68− ( Reifiable context, Reifiable context'
69− , Sql DBType a
70− ) =>
71− Recontextualize
72− (Reify context)
73− (Reify context')
74− (AColumn context a)
75− (AColumn context' a)
76−
77−
78−sfromColumn :: ()
79− => SContext context
80− -> Col context ('Spec labels a)
81− -> AColumn context a
82−sfromColumn = \case
83− SAggregate -> \(A a) -> AColumn a
84− SExpr -> \(E a) -> AColumn a
85− SName -> \(N a) -> AColumn a
86− SResult -> \(R a) -> AColumn a
87− SReify context -> \(Reify a) -> AColumn (sfromColumn context a)
88−
89−
90−stoColumn :: ()
91− => SContext context
92− -> AColumn context a
93− -> Col context ('Spec labels a)
94−stoColumn = \case
95− SAggregate -> \(AColumn a) -> A a
96− SExpr -> \(AColumn a) -> E a
97− SName -> \(AColumn a) -> N a
98− SResult -> \(AColumn a) -> R a
99− SReify context -> \(AColumn a) -> Reify (stoColumn context a)
26+ Column Result a = a
27+ Column context a = context a
10028
10129
10230data TColumn :: K.Context -> Type -> Exp Type
src/Rel8/Column/ADT.hs+3−68
@@ -1,88 +1,23 @@
11{-# language DataKinds #-}
2−{-# language LambdaCase #-}
3−{-# language MultiParamTypeClasses #-}
42{-# language StandaloneKindSignatures #-}
53{-# language TypeFamilies #-}
6−{-# language UndecidableInstances #-}
74
85module Rel8.Column.ADT
9− ( HADT, AHADT(..)
6+ ( HADT
107 )
118where
129
1310-- base
1411import Data.Kind ( Type )
15−import Prelude
12+import Prelude ()
1613
1714-- rel8
18−import Rel8.Generic.Rel8able ( GColumns )
19−import Rel8.Kind.Context ( SContext(..), Reifiable, contextSing )
20−import Rel8.Schema.Context ( Col )
2115import qualified Rel8.Schema.Kind as K
22−import Rel8.Schema.Reify ( Reify, hreify, hunreify )
2316import Rel8.Schema.Result ( Result )
24−import Rel8.Table
25− ( Table, Columns, Context, fromColumns, toColumns
26− , Unreify, reify, unreify
27− )
28−import Rel8.Table.ADT ( ADT( ADT ), ADTable, fromADT, toADT )
29−import Rel8.Table.Recontextualize ( Recontextualize )
17+import Rel8.Table.ADT ( ADT )
3018
3119
3220type HADT :: K.Context -> K.Rel8able -> Type
3321type family HADT context t where
34− HADT (Reify context) t = AHADT context t
3522 HADT Result t = t Result
3623 HADT context t = ADT t context
37−
38−
39−type AHADT :: K.Context -> K.Rel8able -> Type
40−newtype AHADT context t = AHADT (HADT context t)
41−
42−
43−instance (ADTable t, Reifiable context) =>
44− Table (Reify context) (AHADT context t)
45− where
46− type Context (AHADT context t) = Reify context
47− type Columns (AHADT context t) = GColumns (ADT t)
48− type Unreify (AHADT context t) = HADT context t
49−
50− fromColumns = sfromColumnsADT contextSing
51− toColumns = stoColumnsADT contextSing
52− reify _ = AHADT
53− unreify _ (AHADT a) = a
54−
55−
56−instance
57− ( Reifiable context, Reifiable context'
58− , ADTable t, t ~ t'
59− )
60− => Recontextualize
61− (Reify context)
62− (Reify context')
63− (AHADT context t)
64− (AHADT context' t')
65−
66−
67−sfromColumnsADT :: ADTable t
68− => SContext context
69− -> GColumns (ADT t) (Col (Reify context))
70− -> AHADT context t
71−sfromColumnsADT = \case
72− SAggregate -> AHADT . ADT . hunreify
73− SExpr -> AHADT . ADT . hunreify
74− SName -> AHADT . ADT . hunreify
75− SResult -> AHADT . fromADT . ADT . hunreify
76− SReify context -> AHADT . sfromColumnsADT context . hunreify
77−
78−
79−stoColumnsADT :: ADTable t
80− => SContext context
81− -> AHADT context t
82− -> GColumns (ADT t) (Col (Reify context))
83−stoColumnsADT = \case
84− SAggregate -> hreify . (\(AHADT (ADT a)) -> a)
85− SExpr -> hreify . (\(AHADT (ADT a)) -> a)
86− SName -> hreify . (\(AHADT (ADT a)) -> a)
87− SResult -> hreify . (\(ADT a) -> a) . toADT . (\(AHADT a) -> a)
88− SReify context -> hreify . stoColumnsADT context . (\(AHADT a) -> a)
src/Rel8/Column/Either.hs+4−140
@@ -1,162 +1,26 @@
11{-# language DataKinds #-}
2−{-# language FlexibleContexts #-}
3−{-# language LambdaCase #-}
4−{-# language MultiParamTypeClasses #-}
52{-# language StandaloneKindSignatures #-}
6−{-# language TypeFamilies #-}
7−{-# language UndecidableInstances #-}
3+{-# language TypeFamilyDependencies #-}
84
95module Rel8.Column.Either
10− ( HEither, AHEither(..)
6+ ( HEither
117 )
128where
139
1410-- base
15−import Control.Applicative ( liftA2 )
16−import Data.Bifunctor ( Bifunctor, bimap )
1711import Data.Kind ( Type )
1812import Prelude
1913
2014-- rel8
21−import Rel8.Aggregate ( Aggregate )
22−import Rel8.Expr ( Expr )
23−import Rel8.Kind.Context ( SContext(..), Reifiable( contextSing ) )
24−import Rel8.Schema.Context ( Col )
25−import Rel8.Schema.HTable.Either ( HEitherTable )
2615import qualified Rel8.Schema.Kind as K
27−import Rel8.Schema.Name ( Name(..) )
28−import Rel8.Schema.Reify ( Reify, hreify, hunreify )
2916import Rel8.Schema.Result ( Result )
30−import Rel8.Table
31− ( Table, Columns, Context, fromColumns, toColumns
32− , Unreify, reify, unreify
33− )
3417import Rel8.Table.Either ( EitherTable )
35−import Rel8.Table.Recontextualize ( Recontextualize )
3618
3719
3820-- | Nest an 'Either' value within a 'Rel8able'. @HEither f a b@ will produce a
3921-- 'EitherTable' @a b@ in the 'Expr' context, and a 'Either' @a b@ in the
4022-- 'Result' context.
4123type HEither :: K.Context -> Type -> Type -> Type
42−type family HEither context where
43− HEither (Reify context) = AHEither context
44− HEither Aggregate = EitherTable
45− HEither Expr = EitherTable
46− HEither Name = EitherTable
24+type family HEither context = either | either -> context where
4725 HEither Result = Either
48−
49−
50−type AHEither :: K.Context -> Type -> Type -> Type
51−newtype AHEither context a b = AHEither (HEither context a b)
52−
53−
54−instance Reifiable context => Bifunctor (AHEither context) where
55− bimap = sbimapEither contextSing
56−
57−
58−instance Reifiable context => Functor (AHEither context a) where
59− fmap = bimap id
60−
61−
62−instance (Reifiable context, Table (Reify context) a, Table (Reify context) b)
63− => Table (Reify context) (AHEither context a b)
64− where
65− type Context (AHEither context a b) = Reify context
66− type Columns (AHEither context a b) = HEitherTable (Columns a) (Columns b)
67− type Unreify (AHEither context a b) = HEither context (Unreify a) (Unreify b)
68−
69− fromColumns = sfromColumnsEither contextSing
70− toColumns = stoColumnsEither contextSing
71− reify proof = liftA2 bimap reify reify proof . AHEither
72− unreify proof = (\(AHEither a) -> a) . liftA2 bimap unreify unreify proof
73−
74−
75−instance
76− ( Reifiable context, Reifiable context'
77− , Recontextualize (Reify context) (Reify context') a a'
78− , Recontextualize (Reify context) (Reify context') b b'
79− ) =>
80− Recontextualize
81− (Reify context)
82− (Reify context')
83− (AHEither context a b)
84− (AHEither context' a' b')
85−
86−
87−sbimapEither :: ()
88− => SContext context
89− -> (a -> c)
90− -> (b -> d)
91− -> AHEither context a b
92− -> AHEither context c d
93−sbimapEither = \case
94− SAggregate -> \f g (AHEither a) -> AHEither (bimap f g a)
95− SExpr -> \f g (AHEither a) -> AHEither (bimap f g a)
96− SResult -> \f g (AHEither a) -> AHEither (bimap f g a)
97− SName -> \f g (AHEither a) -> AHEither (bimap f g a)
98− SReify context -> \f g (AHEither a) -> AHEither (sbimapEither context f g a)
99−
100−
101−sfromColumnsEither :: (Table (Reify context) a, Table (Reify context) b)
102− => SContext context
103− -> HEitherTable (Columns a) (Columns b) (Col (Reify context))
104− -> AHEither context a b
105−sfromColumnsEither = \case
106− SAggregate ->
107− AHEither .
108− bimap (fromColumns . hreify) (fromColumns . hreify) .
109− fromColumns .
110− hunreify
111− SExpr ->
112− AHEither .
113− bimap (fromColumns . hreify) (fromColumns . hreify) .
114− fromColumns .
115− hunreify
116− SResult ->
117− AHEither .
118− bimap (fromColumns . hreify) (fromColumns . hreify) .
119− fromColumns .
120− hunreify
121− SName ->
122− AHEither .
123− bimap (fromColumns . hreify) (fromColumns . hreify) .
124− fromColumns .
125− hunreify
126− SReify context ->
127− AHEither .
128− sbimapEither context (fromColumns . hreify) (fromColumns . hreify) .
129− sfromColumnsEither context .
130− hunreify
131−
132−
133−stoColumnsEither :: (Table (Reify context) a, Table (Reify context) b)
134− => SContext context
135− -> AHEither context a b
136− -> HEitherTable (Columns a) (Columns b) (Col (Reify context))
137−stoColumnsEither = \case
138− SAggregate ->
139− hreify .
140− toColumns .
141− bimap (hunreify . toColumns) (hunreify . toColumns) .
142− (\(AHEither a) -> a)
143− SExpr ->
144− hreify .
145− toColumns .
146− bimap (hunreify . toColumns) (hunreify . toColumns) .
147− (\(AHEither a) -> a)
148− SResult ->
149− hreify .
150− toColumns .
151− bimap (hunreify . toColumns) (hunreify . toColumns) .
152− (\(AHEither a) -> a)
153− SName ->
154− hreify .
155− toColumns .
156− bimap (hunreify . toColumns) (hunreify . toColumns) .
157− (\(AHEither a) -> a)
158− SReify context ->
159− hreify .
160− stoColumnsEither context .
161− sbimapEither context (hunreify . toColumns) (hunreify . toColumns) .
162− (\(AHEither a) -> a)
26+ HEither context = EitherTable context
src/Rel8/Column/Lift.hs+3−67
@@ -1,87 +1,23 @@
11{-# language DataKinds #-}
2−{-# language LambdaCase #-}
3−{-# language MultiParamTypeClasses #-}
42{-# language StandaloneKindSignatures #-}
53{-# language TypeFamilies #-}
64
75module Rel8.Column.Lift
8− ( Lift, ALift(..)
6+ ( Lift
97 )
108where
119
1210-- base
1311import Data.Kind ( Type )
14−import Prelude
12+import Prelude ()
1513
1614-- rel8
17−import Rel8.Generic.Rel8able ( GColumns )
18−import Rel8.Kind.Context ( Reifiable(..), SContext(..) )
19−import Rel8.Schema.Context ( Col )
2015import qualified Rel8.Schema.Kind as K
21−import Rel8.Schema.Reify ( Reify, hreify, hunreify )
2216import Rel8.Schema.Result ( Result )
23−import Rel8.Table
24− ( Table, Columns, Context, fromColumns, toColumns
25− , Unreify, reify, unreify
26− )
27−import Rel8.Table.Rel8able ()
28−import Rel8.Table.HKD ( HKD( HKD ), HKDable, fromHKD, toHKD )
29−import Rel8.Table.Recontextualize ( Recontextualize )
17+import Rel8.Table.HKD ( HKD )
3018
3119
3220type Lift :: K.Context -> Type -> Type
3321type family Lift context a where
34− Lift (Reify context) a = ALift context a
3522 Lift Result a = a
3623 Lift context a = HKD a context
37−
38−
39−type ALift :: K.Context -> Type -> Type
40−newtype ALift context a = ALift
41− { unALift :: Lift context a
42− }
43−
44−
45−instance (Reifiable context, HKDable a) =>
46− Table (Reify context) (ALift context a)
47− where
48− type Context (ALift context a) = Reify context
49− type Columns (ALift context a) = GColumns (HKD a)
50− type Unreify (ALift context a) = Lift context a
51−
52− fromColumns = sfromColumnsLift contextSing
53− toColumns = stoColumnsLift contextSing
54− reify _ = ALift
55− unreify _ (ALift a) = a
56−
57−
58−instance (Reifiable context, Reifiable context', HKDable a) =>
59− Recontextualize
60− (Reify context)
61− (Reify context')
62− (ALift context a)
63− (ALift context' a)
64−
65−
66−sfromColumnsLift :: HKDable a
67− => SContext context
68− -> GColumns (HKD a) (Col (Reify context))
69− -> ALift context a
70−sfromColumnsLift = \case
71− SAggregate -> ALift . fromColumns . hunreify
72− SExpr -> ALift . fromColumns . hunreify
73− SName -> ALift . fromColumns . hunreify
74− SResult -> ALift . fromHKD . HKD . hunreify
75− SReify context -> ALift . sfromColumnsLift context . hunreify
76−
77−
78−stoColumnsLift :: HKDable a
79− => SContext context
80− -> ALift context a
81− -> GColumns (HKD a) (Col (Reify context))
82−stoColumnsLift = \case
83− SAggregate -> hreify . toColumns . unALift
84− SExpr -> hreify . toColumns . unALift
85− SName -> hreify . toColumns . unALift
86− SResult -> hreify . (\(HKD a) -> a) . toHKD . unALift
87− SReify context -> hreify . stoColumnsLift context . unALift
src/Rel8/Column/List.hs+6−126
@@ -1,145 +1,25 @@
11{-# language DataKinds #-}
2−{-# language FlexibleContexts #-}
3−{-# language LambdaCase #-}
4−{-# language MultiParamTypeClasses #-}
52{-# language StandaloneKindSignatures #-}
6−{-# language TypeFamilies #-}
7−{-# language UndecidableInstances #-}
3+{-# language TypeFamilyDependencies #-}
84
95module Rel8.Column.List
10− ( HList, AHList(..)
6+ ( HList
117 )
128where
139
1410-- base
1511import Data.Kind ( Type )
16−import Data.Type.Equality ( (:~:)( Refl ) )
17−import Prelude
12+import Prelude ()
1813
1914-- rel8
20−import Rel8.Aggregate ( Aggregate )
21−import Rel8.Expr ( Expr )
22−import Rel8.Kind.Context ( SContext(..), Reifiable( contextSing ) )
23−import Rel8.Schema.Context ( Col )
24−import Rel8.Schema.HTable.List ( HListTable )
2515import qualified Rel8.Schema.Kind as K
26−import Rel8.Schema.Name ( Name )
27−import Rel8.Schema.Reify ( Reify, hreify, hunreify )
2816import Rel8.Schema.Result ( Result )
29−import Rel8.Table
30− ( Table, Columns, Congruent, Context, fromColumns, toColumns
31− , Unreify, reify, unreify
32− )
33−import Rel8.Table.List ( ListTable( ListTable ) )
34−import Rel8.Table.Recontextualize ( Recontextualize )
35−import Rel8.Table.Unreify ( Unreifiability(..), Unreifiable, unreifiability )
17+import Rel8.Table.List ( ListTable )
3618
3719
3820-- | Nest a list within a 'Rel8able'. @HList f a@ will produce a 'ListTable'
3921-- @a@ in the 'Expr' context, and a @[a]@ in the 'Result' context.
4022type HList :: K.Context -> Type -> Type
41−type family HList context where
42− HList (Reify context) = AHList context
43− HList Aggregate = ListTable
44− HList Expr = ListTable
45− HList Name = ListTable
23+type family HList context = list | list -> context where
4624 HList Result = []
47−
48−
49−type AHList :: K.Context -> Type -> Type
50−newtype AHList context a = AHList (HList context a)
51−
52−
53−instance (Reifiable context, Unreifiable a, Table (Reify context) a) =>
54− Table (Reify context) (AHList context a)
55− where
56− type Context (AHList context a) = Reify context
57− type Columns (AHList context a) = HListTable (Columns a)
58− type Unreify (AHList context a) = HList context (Unreify a)
59−
60− fromColumns = sfromColumnsList contextSing
61− toColumns = stoColumnsList contextSing
62−
63− reify _ = sreifyList (unreifiability contextSing)
64− unreify _ = sunreifyList (unreifiability contextSing)
65−
66−
67−instance
68− ( Reifiable context, Reifiable context'
69− , Unreifiable a, Unreifiable a'
70− , Recontextualize (Reify context) (Reify context') a a'
71− )
72− => Recontextualize
73− (Reify context)
74− (Reify context')
75− (AHList context a)
76− (AHList context' a')
77−
78−
79−smapList :: Congruent a b
80− => SContext context
81− -> (a -> b)
82− -> (HListTable (Columns a) (Col (Context a)) -> HListTable (Columns b) (Col (Context b)))
83− -> AHList context a
84− -> AHList context b
85−smapList = \case
86− SAggregate -> \_ f (AHList (ListTable a)) -> AHList (ListTable (f a))
87− SExpr -> \_ f (AHList (ListTable a)) -> AHList (ListTable (f a))
88− SResult -> \f _ (AHList as) -> AHList (fmap f as)
89− SName -> \_ f (AHList (ListTable a)) -> AHList (ListTable (f a))
90− SReify context -> \f g (AHList as) -> AHList (smapList context f g as)
91−
92−
93−sfromColumnsList :: Table (Reify context) a
94− => SContext context
95− -> HListTable (Columns a) (Col (Reify context))
96− -> AHList context a
97−sfromColumnsList = \case
98− SAggregate -> AHList . ListTable
99− SExpr -> AHList . ListTable
100− SResult -> AHList . fmap (fromColumns . hreify) . fromColumns . hunreify
101− SName -> AHList . ListTable
102− SReify context ->
103− AHList .
104− smapList context (fromColumns . hreify) hreify .
105− sfromColumnsList context .
106− hunreify
107−
108−
109−stoColumnsList :: Table (Reify context) a
110− => SContext context
111− -> AHList context a
112− -> HListTable (Columns a) (Col (Reify context))
113−stoColumnsList = \case
114− SAggregate -> \(AHList (ListTable a)) -> a
115− SExpr -> \(AHList (ListTable a)) -> a
116− SResult ->
117− hreify . toColumns . fmap (hunreify . toColumns) . (\(AHList a) -> a)
118− SName -> \(AHList (ListTable a)) -> a
119− SReify context ->
120− hreify .
121− stoColumnsList context .
122− smapList context (hunreify . toColumns) hunreify .
123− (\(AHList a) -> a)
124−
125−
126−sreifyList :: Table (Reify context) a
127− => Unreifiability context a
128− -> HList context (Unreify a)
129− -> AHList context a
130−sreifyList = \case
131− UResult -> AHList . fmap (reify Refl)
132− Unreifiability context ->
133− smapList context (reify Refl) hreify .
134− AHList
135−
136−
137−sunreifyList :: Table (Reify context) a
138− => Unreifiability context a
139− -> AHList context a
140− -> HList context (Unreify a)
141−sunreifyList = \case
142− UResult -> fmap (unreify Refl) . (\(AHList a) -> a)
143− Unreifiability context ->
144− (\(AHList a) -> a) .
145− smapList context (unreify Refl) hunreify
25+ HList context = ListTable context
src/Rel8/Column/Maybe.hs+4−105
@@ -1,14 +1,9 @@
11{-# language DataKinds #-}
2−{-# language FlexibleContexts #-}
3−{-# language GADTs #-}
4−{-# language LambdaCase #-}
5−{-# language MultiParamTypeClasses #-}
62{-# language StandaloneKindSignatures #-}
7−{-# language TypeFamilies #-}
8−{-# language UndecidableInstances #-}
3+{-# language TypeFamilyDependencies #-}
94
105module Rel8.Column.Maybe
11− ( HMaybe, AHMaybe(..)
6+ ( HMaybe
127 )
138where
149
@@ -17,111 +12,15 @@ import Data.Kind ( Type )
1712import Prelude
1813
1914-- rel8
20−import Rel8.Aggregate ( Aggregate )
21−import Rel8.Expr ( Expr )
22−import Rel8.Kind.Context ( SContext(..), Reifiable( contextSing ) )
23−import Rel8.Schema.Context ( Col )
24−import Rel8.Schema.HTable.Maybe ( HMaybeTable )
2515import qualified Rel8.Schema.Kind as K
26−import Rel8.Schema.Name ( Name )
27−import Rel8.Schema.Reify ( Reify, hreify, hunreify )
2816import Rel8.Schema.Result ( Result )
29−import Rel8.Table
30− ( Table, Columns, Context, fromColumns, toColumns
31− , Unreify, reify, unreify
32− )
3317import Rel8.Table.Maybe ( MaybeTable )
34−import Rel8.Table.Recontextualize ( Recontextualize )
3518
3619
3720-- | Nest a 'Maybe' value within a 'Rel8able'. @HMaybe f a@ will produce a
3821-- 'MaybeTable' @a@ in the 'Expr' context, and a 'Maybe' @a@ in the 'Result'
3922-- context.
4023type HMaybe :: K.Context -> Type -> Type
41−type family HMaybe context where
42− HMaybe (Reify context) = AHMaybe context
43− HMaybe Aggregate = MaybeTable
44− HMaybe Expr = MaybeTable
45− HMaybe Name = MaybeTable
24+type family HMaybe context = maybe | maybe -> context where
4625 HMaybe Result = Maybe
47−
48−
49−type AHMaybe :: K.Context -> Type -> Type
50−newtype AHMaybe context a = AHMaybe (HMaybe context a)
51−
52−
53−instance Reifiable context => Functor (AHMaybe context) where
54− fmap = smapMaybe contextSing
55−
56−
57−instance (Reifiable context, Table (Reify context) a) =>
58− Table (Reify context) (AHMaybe context a)
59− where
60− type Context (AHMaybe context a) = Reify context
61− type Columns (AHMaybe context a) = HMaybeTable (Columns a)
62− type Unreify (AHMaybe context a) = HMaybe context (Unreify a)
63−
64− fromColumns = sfromColumnsMaybe contextSing
65− toColumns = stoColumnsMaybe contextSing
66− reify proof = fmap fmap reify proof . AHMaybe
67− unreify proof = (\(AHMaybe a) -> a) . fmap fmap unreify proof
68−
69−
70−instance
71− ( Reifiable context, Reifiable context'
72− , Recontextualize (Reify context) (Reify context') a a'
73− ) =>
74− Recontextualize
75− (Reify context)
76− (Reify context')
77− (AHMaybe context a)
78− (AHMaybe context' a')
79−
80−
81−smapMaybe :: ()
82− => SContext context
83− -> (a -> b)
84− -> AHMaybe context a
85− -> AHMaybe context b
86−smapMaybe = \case
87− SAggregate -> \f (AHMaybe a) -> AHMaybe (fmap f a)
88− SExpr -> \f (AHMaybe a) -> AHMaybe (fmap f a)
89− SResult -> \f (AHMaybe a) -> AHMaybe (fmap f a)
90− SName -> \f (AHMaybe a) -> AHMaybe (fmap f a)
91− SReify context -> \f (AHMaybe a) -> AHMaybe (smapMaybe context f a)
92−
93−
94−sfromColumnsMaybe :: Table (Reify context) a
95− => SContext context
96− -> HMaybeTable (Columns a) (Col (Reify context))
97− -> AHMaybe context a
98−sfromColumnsMaybe = \case
99− SAggregate -> AHMaybe . fmap (fromColumns . hreify) . fromColumns . hunreify
100− SExpr -> AHMaybe . fmap (fromColumns . hreify) . fromColumns . hunreify
101− SResult -> AHMaybe . fmap (fromColumns . hreify) . fromColumns . hunreify
102− SName -> AHMaybe . fmap (fromColumns . hreify) . fromColumns . hunreify
103− SReify context ->
104− AHMaybe .
105− smapMaybe context (fromColumns . hreify) .
106− sfromColumnsMaybe context .
107− hunreify
108−
109−
110−stoColumnsMaybe :: Table (Reify context) a
111− => SContext context
112− -> AHMaybe context a
113− -> HMaybeTable (Columns a) (Col (Reify context))
114−stoColumnsMaybe = \case
115− SAggregate ->
116− hreify . toColumns . fmap (hunreify . toColumns) . (\(AHMaybe a) -> a)
117− SExpr ->
118− hreify . toColumns . fmap (hunreify . toColumns) . (\(AHMaybe a) -> a)
119− SResult ->
120− hreify . toColumns . fmap (hunreify . toColumns) . (\(AHMaybe a) -> a)
121− SName ->
122− hreify . toColumns . fmap (hunreify . toColumns) . (\(AHMaybe a) -> a)
123− SReify context ->
124− hreify .
125− stoColumnsMaybe context .
126− smapMaybe context (hunreify . toColumns) .
127− (\(AHMaybe a) -> a)
26+ HMaybe context = MaybeTable context
src/Rel8/Column/NonEmpty.hs+6−127
@@ -1,148 +1,27 @@
11{-# language DataKinds #-}
2−{-# language FlexibleContexts #-}
3−{-# language LambdaCase #-}
4−{-# language MultiParamTypeClasses #-}
52{-# language StandaloneKindSignatures #-}
6−{-# language TypeFamilies #-}
7−{-# language UndecidableInstances #-}
3+{-# language TypeFamilyDependencies #-}
84
95module Rel8.Column.NonEmpty
10− ( HNonEmpty, AHNonEmpty(..)
6+ ( HNonEmpty
117 )
128where
139
1410-- base
1511import Data.Kind ( Type )
1612import Data.List.NonEmpty ( NonEmpty )
17−import Data.Type.Equality ( (:~:)( Refl ) )
18−import Prelude
13+import Prelude ()
1914
2015-- rel8
21−import Rel8.Aggregate ( Aggregate )
22−import Rel8.Expr ( Expr )
23−import Rel8.Kind.Context ( SContext(..), Reifiable( contextSing ) )
24−import Rel8.Schema.Context ( Col )
25−import Rel8.Schema.HTable.NonEmpty ( HNonEmptyTable )
2616import qualified Rel8.Schema.Kind as K
27−import Rel8.Schema.Name ( Name )
28−import Rel8.Schema.Reify ( Reify, hreify, hunreify )
2917import Rel8.Schema.Result ( Result )
30−import Rel8.Table
31− ( Table, Columns, Congruent, Context, fromColumns, toColumns
32− , Unreify, reify, unreify
33− )
34−import Rel8.Table.NonEmpty ( NonEmptyTable( NonEmptyTable ) )
35−import Rel8.Table.Recontextualize ( Recontextualize )
36−import Rel8.Table.Unreify ( Unreifiability(..), Unreifiable, unreifiability )
18+import Rel8.Table.NonEmpty ( NonEmptyTable )
3719
3820
3921-- | Nest a 'NonEmpty' list within a 'Rel8able'. @HNonEmpty f a@ will produce a
4022-- 'NonEmptyTable' @a@ in the 'Expr' context, and a 'NonEmpty' @a@ in the
4123-- 'Result' context.
4224type HNonEmpty :: K.Context -> Type -> Type
43−type family HNonEmpty context where
44− HNonEmpty (Reify context) = AHNonEmpty context
45− HNonEmpty Aggregate = NonEmptyTable
46− HNonEmpty Expr = NonEmptyTable
47− HNonEmpty Name = NonEmptyTable
25+type family HNonEmpty context = nonEmpty | nonEmpty -> context where
4826 HNonEmpty Result = NonEmpty
49−
50−
51−type AHNonEmpty :: K.Context -> Type -> Type
52−newtype AHNonEmpty context a = AHNonEmpty (HNonEmpty context a)
53−
54−
55−instance (Reifiable context, Unreifiable a, Table (Reify context) a) =>
56− Table (Reify context) (AHNonEmpty context a)
57− where
58− type Context (AHNonEmpty context a) = Reify context
59− type Columns (AHNonEmpty context a) = HNonEmptyTable (Columns a)
60− type Unreify (AHNonEmpty context a) = HNonEmpty context (Unreify a)
61−
62− fromColumns = sfromColumnsNonEmpty contextSing
63− toColumns = stoColumnsNonEmpty contextSing
64−
65− reify _ = sreifyNonEmpty (unreifiability contextSing)
66− unreify _ = sunreifyNonEmpty (unreifiability contextSing)
67−
68−
69−instance
70− ( Reifiable context, Reifiable context'
71− , Unreifiable a, Unreifiable a'
72− , Recontextualize (Reify context) (Reify context') a a'
73− )
74− => Recontextualize
75− (Reify context)
76− (Reify context')
77− (AHNonEmpty context a)
78− (AHNonEmpty context' a')
79−
80−
81−smapNonEmpty :: Congruent a b
82− => SContext context
83− -> (a -> b)
84− -> (HNonEmptyTable (Columns a) (Col (Context a)) -> HNonEmptyTable (Columns b) (Col (Context b)))
85− -> AHNonEmpty context a
86− -> AHNonEmpty context b
87−smapNonEmpty = \case
88− SAggregate -> \_ f (AHNonEmpty (NonEmptyTable a)) -> AHNonEmpty (NonEmptyTable (f a))
89− SExpr -> \_ f (AHNonEmpty (NonEmptyTable a)) -> AHNonEmpty (NonEmptyTable (f a))
90− SResult -> \f _ (AHNonEmpty as) -> AHNonEmpty (fmap f as)
91− SName -> \_ f (AHNonEmpty (NonEmptyTable a)) -> AHNonEmpty (NonEmptyTable (f a))
92− SReify context -> \f g (AHNonEmpty as) -> AHNonEmpty (smapNonEmpty context f g as)
93−
94−
95−sfromColumnsNonEmpty :: Table (Reify context) a
96− => SContext context
97− -> HNonEmptyTable (Columns a) (Col (Reify context))
98− -> AHNonEmpty context a
99−sfromColumnsNonEmpty = \case
100− SAggregate -> AHNonEmpty . NonEmptyTable
101− SExpr -> AHNonEmpty . NonEmptyTable
102− SResult ->
103− AHNonEmpty . fmap (fromColumns . hreify) . fromColumns . hunreify
104− SName -> AHNonEmpty . NonEmptyTable
105− SReify context ->
106− AHNonEmpty .
107− smapNonEmpty context (fromColumns . hreify) hreify .
108− sfromColumnsNonEmpty context .
109− hunreify
110−
111−
112−stoColumnsNonEmpty :: Table (Reify context) a
113− => SContext context
114− -> AHNonEmpty context a
115− -> HNonEmptyTable (Columns a) (Col (Reify context))
116−stoColumnsNonEmpty = \case
117− SAggregate -> \(AHNonEmpty (NonEmptyTable a)) -> a
118− SExpr -> \(AHNonEmpty (NonEmptyTable a)) -> a
119− SResult ->
120− hreify . toColumns . fmap (hunreify . toColumns) . (\(AHNonEmpty a) -> a)
121− SName -> \(AHNonEmpty (NonEmptyTable a)) -> a
122− SReify context ->
123− hreify .
124− stoColumnsNonEmpty context .
125− smapNonEmpty context (hunreify . toColumns) hunreify .
126− (\(AHNonEmpty a) -> a)
127−
128−
129−sreifyNonEmpty :: Table (Reify context) a
130− => Unreifiability context a
131− -> HNonEmpty context (Unreify a)
132− -> AHNonEmpty context a
133−sreifyNonEmpty = \case
134− UResult -> AHNonEmpty . fmap (reify Refl)
135− Unreifiability context ->
136− smapNonEmpty context (reify Refl) hreify .
137− AHNonEmpty
138−
139−
140−sunreifyNonEmpty :: Table (Reify context) a
141− => Unreifiability context a
142− -> AHNonEmpty context a
143− -> HNonEmpty context (Unreify a)
144−sunreifyNonEmpty = \case
145− UResult -> fmap (unreify Refl) . (\(AHNonEmpty a) -> a)
146− Unreifiability context ->
147− (\(AHNonEmpty a) -> a) .
148− smapNonEmpty context (unreify Refl) hunreify
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.hs+5−142
@@ -1,38 +1,19 @@
11{-# language DataKinds #-}
2−{-# language FlexibleContexts #-}
3−{-# language GADTs #-}
4−{-# language LambdaCase #-}
5−{-# language MultiParamTypeClasses #-}
62{-# language StandaloneKindSignatures #-}
7−{-# language TypeFamilies #-}
8−{-# language UndecidableInstances #-}
3+{-# language TypeFamilyDependencies #-}
94
105module Rel8.Column.These
11− ( HThese, AHThese(..)
6+ ( HThese
127 )
138where
149
1510-- base
16−import Control.Applicative ( liftA2 )
17−import Data.Bifunctor ( Bifunctor, bimap )
1811import Data.Kind ( Type )
19−import Prelude
12+import Prelude ()
2013
2114-- rel8
22−import Rel8.Aggregate ( Aggregate )
23−import Rel8.Expr ( Expr )
24−import Rel8.Kind.Context ( SContext(..), Reifiable( contextSing ) )
25−import Rel8.Schema.Context ( Col )
26−import Rel8.Schema.HTable.These ( HTheseTable )
2715import qualified Rel8.Schema.Kind as K
28−import Rel8.Schema.Name ( Name )
29−import Rel8.Schema.Reify ( Reify, hreify, hunreify )
3016import Rel8.Schema.Result ( Result )
31−import Rel8.Table
32− ( Table, Columns, Context, fromColumns, toColumns
33− , Unreify, reify, unreify
34− )
35−import Rel8.Table.Recontextualize ( Recontextualize )
3617import Rel8.Table.These ( TheseTable )
3718
3819-- these
@@ -43,124 +24,6 @@ import Data.These ( These )
4324-- 'TheseTable' @a b@ in the 'Expr' context, and a 'These' @a b@ in the
4425-- 'Result' context.
4526type HThese :: K.Context -> Type -> Type -> Type
46−type family HThese context where
47− HThese (Reify context) = AHThese context
48− HThese Aggregate = TheseTable
49− HThese Expr = TheseTable
50− HThese Name = TheseTable
27+type family HThese context = these | these -> context where
5128 HThese Result = These
52−
53−
54−type AHThese :: K.Context -> Type -> Type -> Type
55−newtype AHThese context a b = AHThese (HThese context a b)
56−
57−
58−instance Reifiable context => Bifunctor (AHThese context) where
59− bimap = sbimapThese contextSing
60−
61−
62−instance Reifiable context => Functor (AHThese context a) where
63− fmap = bimap id
64−
65−
66−instance (Reifiable context, Table (Reify context) a, Table (Reify context) b)
67− => Table (Reify context) (AHThese context a b)
68− where
69− type Context (AHThese context a b) = Reify context
70− type Columns (AHThese context a b) = HTheseTable (Columns a) (Columns b)
71− type Unreify (AHThese context a b) = HThese context (Unreify a) (Unreify b)
72−
73− fromColumns = sfromColumnsThese contextSing
74− toColumns = stoColumnsThese contextSing
75− reify proof = liftA2 bimap reify reify proof . AHThese
76− unreify proof = (\(AHThese a) -> a) . liftA2 bimap unreify unreify proof
77−
78−
79−instance
80− ( Reifiable context, Reifiable context'
81− , Recontextualize (Reify context) (Reify context') a a'
82− , Recontextualize (Reify context) (Reify context') b b'
83− ) =>
84− Recontextualize
85− (Reify context)
86− (Reify context')
87− (AHThese context a b)
88− (AHThese context' a' b')
89−
90−
91−sbimapThese :: ()
92− => SContext context
93− -> (a -> c)
94− -> (b -> d)
95− -> AHThese context a b
96− -> AHThese context c d
97−sbimapThese = \case
98− SAggregate -> \f g (AHThese a) -> AHThese (bimap f g a)
99− SExpr -> \f g (AHThese a) -> AHThese (bimap f g a)
100− SResult -> \f g (AHThese a) -> AHThese (bimap f g a)
101− SName -> \f g (AHThese a) -> AHThese (bimap f g a)
102− SReify context -> \f g (AHThese a) -> AHThese (sbimapThese context f g a)
103−
104−
105−sfromColumnsThese :: (Table (Reify context) a, Table (Reify context) b)
106− => SContext context
107− -> HTheseTable (Columns a) (Columns b) (Col (Reify context))
108− -> AHThese context a b
109−sfromColumnsThese = \case
110− SAggregate ->
111− AHThese .
112− bimap (fromColumns . hreify) (fromColumns . hreify) .
113− fromColumns .
114− hunreify
115− SExpr ->
116− AHThese .
117− bimap (fromColumns . hreify) (fromColumns . hreify) .
118− fromColumns .
119− hunreify
120− SResult ->
121− AHThese .
122− bimap (fromColumns . hreify) (fromColumns . hreify) .
123− fromColumns .
124− hunreify
125− SName ->
126− AHThese .
127− bimap (fromColumns . hreify) (fromColumns . hreify) .
128− fromColumns .
129− hunreify
130− SReify context ->
131− AHThese .
132− sbimapThese context (fromColumns . hreify) (fromColumns . hreify) .
133− sfromColumnsThese context .
134− hunreify
135−
136−
137−stoColumnsThese :: (Table (Reify context) a, Table (Reify context) b)
138− => SContext context
139− -> AHThese context a b
140− -> HTheseTable (Columns a) (Columns b) (Col (Reify context))
141−stoColumnsThese = \case
142− SAggregate ->
143− hreify .
144− toColumns .
145− bimap (hunreify . toColumns) (hunreify . toColumns) .
146− (\(AHThese a) -> a)
147− SExpr ->
148− hreify .
149− toColumns .
150− bimap (hunreify . toColumns) (hunreify . toColumns) .
151− (\(AHThese a) -> a)
152− SResult ->
153− hreify .
154− toColumns .
155− bimap (hunreify . toColumns) (hunreify . toColumns) .
156− (\(AHThese a) -> a)
157− SName ->
158− hreify .
159− toColumns .
160− bimap (hunreify . toColumns) (hunreify . toColumns) .
161− (\(AHThese a) -> a)
162− SReify context ->
163− hreify .
164− stoColumnsThese context .
165− sbimapThese context (hunreify . toColumns) (hunreify . toColumns) .
166− (\(AHThese a) -> a)
29+ HThese context = TheseTable context
src/Rel8/Expr.hs+17−47
@@ -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( E, unE )
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
@@ -38,17 +32,14 @@ import Rel8.Expr.Opaleye
3832 , zipPrimExprsWith
3933 )
4034import Rel8.Expr.Serialize ( litExpr )
41−import Rel8.Schema.Context ( Interpretation, Col )
42−import Rel8.Schema.Context.Label ( Labelable, labeler, unlabeler )
43−import Rel8.Schema.HTable.Identity ( HIdentity( HType ), HType )
35+import Rel8.Schema.HTable.Identity ( HIdentity( HIdentity ) )
36+import qualified Rel8.Schema.Kind as K
4437import Rel8.Schema.Null ( Nullity( Null, NotNull ), Sql, nullable )
45−import Rel8.Schema.Reify ( notReify )
46−import Rel8.Schema.Result ( Result )
47−import Rel8.Schema.Spec ( Spec( Spec ) )
4838import Rel8.Table
49− ( Table, Columns, Context, fromColumns, toColumns, reify, unreify
39+ ( Table, Columns, Context, fromColumns, toColumns
40+ , FromExprs, fromResult, toResult
41+ , Transpose
5042 )
51−import Rel8.Table.Recontextualize ( Recontextualize )
5243import Rel8.Type ( DBType )
5344import Rel8.Type.Monoid ( DBMonoid, memptyExpr )
5445import Rel8.Type.Num ( DBFloating, DBFractional, DBNum )
@@ -56,13 +47,9 @@ import Rel8.Type.Semigroup ( DBSemigroup, (<>.) )
5647
5748
5849-- | Typed SQL expressions.
59−type role Expr representational
60−type Expr :: k -> Type
61−data Expr a where
62− Expr :: k ~ Type => !Opaleye.PrimExpr -> Expr (a :: k)
63−
64−
65−deriving stock instance Show (Expr a)
50+type Expr :: K.Context
51+newtype Expr a = Expr Opaleye.PrimExpr
52+ deriving stock Show
6653
6754
6855instance Sql DBSemigroup a => Semigroup (Expr a) where
@@ -126,30 +113,13 @@ instance Sql DBFloating a => Floating (Expr a) where
126113 atanh = function "atanh"
127114
128115
129−instance Interpretation Expr where
130− data Col Expr _spec where
131− E :: {unE :: !(Expr a)} -> Col Expr ('Spec labels a)
132−
133−
134116instance Sql DBType a => Table Expr (Expr a) where
135− type Columns (Expr a) = HType a
117+ type Columns (Expr a) = HIdentity a
136118 type Context (Expr a) = Expr
119+ type FromExprs (Expr a) = a
120+ type Transpose to (Expr a) = to a
137121
138− toColumns a = HType (E a)
139− fromColumns (HType (E a)) = a
140− reify = notReify
141− unreify = notReify
142−
143−
144−instance Sql DBType a => Recontextualize Expr Expr (Expr a) (Expr a)
145−
146−
147−instance Sql DBType a => Recontextualize Expr Result (Expr a) (Identity a)
148−
149−
150−instance Sql DBType a => Recontextualize Result Expr (Identity a) (Expr a)
151−
152−
153−instance Labelable Expr where
154− labeler (E a) = E a
155− unlabeler (E a) = E 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+25−64
@@ -10,6 +10,7 @@ module Rel8.Expr.Aggregate
1010 , and, or
1111 , min, max
1212 , sum, sumWhere
13+ , avg
1314 , stringAgg
1415 , groupByExpr
1516 , listAggExpr, nonEmptyAggExpr
@@ -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
@@ -50,23 +53,13 @@ import Rel8.Type.Sum ( DBSum )
5053
5154-- | Count the occurances of a single column. Corresponds to @COUNT(a)@
5255count :: Expr a -> Aggregate Int64
53−count = unsafeMakeAggregate toPrimExpr fromPrimExpr $
54− Just Aggregator
55− { operation = Opaleye.AggrCount
56− , ordering = []
57− , distinction = Opaleye.AggrAll
58− }
59−
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)@
6360countDistinct :: 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(*)@.
@@ -81,56 +74,39 @@ countWhere condition = count (caseExpr [(condition, litExpr (Just True))] null)
8174
8275-- | Corresponds to @bool_and@.
8376and :: Expr Bool -> Aggregate Bool
84−and = unsafeMakeAggregate toPrimExpr fromPrimExpr $
85− Just Aggregator
86− { operation = Opaleye.AggrBoolAnd
87− , ordering = []
88− , distinction = Opaleye.AggrAll
89− }
77+and = unsafeMakeAggregate toPrimExpr fromPrimExpr Opaleye.boolAnd
9078
9179
9280-- | Corresponds to @bool_or@.
9381or :: Expr Bool -> Aggregate Bool
94−or = unsafeMakeAggregate toPrimExpr fromPrimExpr $
95− Just Aggregator
96− { operation = Opaleye.AggrBoolOr
97− , ordering = []
98− , distinction = Opaleye.AggrAll
99− }
82+or = unsafeMakeAggregate toPrimExpr fromPrimExpr Opaleye.boolOr
10083
10184
10285-- | Produce an aggregation for @Expr a@ using the @max@ function.
10386max :: Sql DBMax a => Expr a -> Aggregate a
104−max = unsafeMakeAggregate toPrimExpr fromPrimExpr $
105− Just Aggregator
106− { operation = Opaleye.AggrMax
107− , ordering = []
108− , distinction = Opaleye.AggrAll
109− }
87+max = unsafeMakeAggregate toPrimExpr fromPrimExpr Opaleye.unsafeMax
11088
11189
11290-- | Produce an aggregation for @Expr a@ using the @max@ function.
11391min :: Sql DBMin a => Expr a -> Aggregate a
114−min = unsafeMakeAggregate toPrimExpr fromPrimExpr $
115− Just Aggregator
116− { operation = Opaleye.AggrMin
117− , ordering = []
118− , distinction = Opaleye.AggrAll
119− }
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.
12699sum :: Sql DBSum a => Expr a -> Aggregate a
127−sum = unsafeMakeAggregate toPrimExpr (castExpr . fromPrimExpr) $
128− Just Aggregator
129− { operation = Opaleye.AggrSum
130− , ordering = []
131− , distinction = Opaleye.AggrAll
132− }
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)
@@ -142,17 +118,12 @@ sumWhere condition a = sum (caseExpr [(condition, a)] 0)
142118stringAgg :: Sql DBString a
143119 => 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.
154125groupByExpr :: Sql DBEq a => Expr a -> Aggregate a
155−groupByExpr = unsafeMakeAggregate toPrimExpr fromPrimExpr Nothing
126+groupByExpr = unsafeMakeAggregate toPrimExpr fromPrimExpr Opaleye.groupBy
156127
157128
158129-- | Collect expressions values as a list.
@@ -167,23 +138,13 @@ nonEmptyAggExpr = snonEmptyAggExpr typeInformation
167138
168139slistAggExpr :: ()
169140 => TypeInformation (Unnullify a) -> Expr a -> Aggregate [a]
170−slistAggExpr info = unsafeMakeAggregate to fromPrimExpr $ Just
171− Aggregator
172− { operation = Opaleye.AggrArr
173− , ordering = []
174− , distinction = Opaleye.AggrAll
175− }
141+slistAggExpr info = unsafeMakeAggregate to fromPrimExpr Opaleye.arrayAgg
176142 where
177143 to = encodeArrayElement info . toPrimExpr
178144
179145
180146snonEmptyAggExpr :: ()
181147 => TypeInformation (Unnullify a) -> Expr a -> Aggregate (NonEmpty a)
182−snonEmptyAggExpr info = unsafeMakeAggregate to fromPrimExpr $ Just
183− Aggregator
184− { operation = Opaleye.AggrArr
185− , ordering = []
186− , distinction = Opaleye.AggrAll
187− }
148+snonEmptyAggExpr info = unsafeMakeAggregate to fromPrimExpr Opaleye.arrayAgg
188149 where
189150 to = encodeArrayElement info . toPrimExpr
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/Num.hs+39−6
@@ -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
@@ -42,14 +48,41 @@ ceiling :: (Sql DBFractional a, Sql DBIntegral b, Homonullable a b)
4248ceiling = 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
src/Rel8/Expr/Opaleye.hs+12−3
@@ -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
@@ -80,9 +83,15 @@ traversePrimExpr :: Functor f
8083traversePrimExpr f = fmap fromPrimExpr . f . toPrimExpr
8184
8285
83−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
8493toColumn = Opaleye.Column
8594
8695
87−fromColumn :: Opaleye.Column b -> Opaleye.PrimExpr
96+fromColumn :: Opaleye.Field_ n b -> Opaleye.PrimExpr
8897fromColumn (Opaleye.Column a) = a
src/Rel8/Expr/Sequence.hs+2−1
@@ -11,6 +11,7 @@ import Prelude
1111import Rel8.Expr ( Expr )
1212import Rel8.Expr.Function ( function )
1313import Rel8.Expr.Serialize ( litExpr )
14+import Rel8.Expr.Text ( quoteIdent )
1415
1516-- text
1617import Data.Text ( pack )
@@ -18,4 +19,4 @@ import Data.Text ( pack )
1819
1920-- | See https://www.postgresql.org/docs/current/functions-sequence.html
2021nextval :: String -> Expr Int64
21−nextval = function "nextval" . litExpr . pack
22+nextval = function "nextval" . quoteIdent . litExpr . pack
src/Rel8/Expr/Text.hs+23−2
@@ -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 )
@@ -49,7 +52,7 @@ infixr 6 ++.
4952
5053
5154-- | Matches regular expression, case sensitive
52−--
55+--
5356-- Corresponds to the @~.@ operator.
5457(~.) :: Expr Text -> Expr Text -> Expr Bool
5558(~.) = binaryOperator "~."
@@ -273,3 +276,21 @@ substr a b Nothing = function "substr" a b
273276-- | Corresponds to the @translate@ function.
274277translate :: Expr Text -> Expr Text -> Expr Text -> Expr Text
275278translate = 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/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+3−3
@@ -5,7 +5,7 @@
55
66module Rel8.FCF
77 ( Exp, Eval
8− , Compose
8+ , Id
99 )
1010where
1111
@@ -22,5 +22,5 @@ type Eval :: Exp e -> e
2222type family Eval a
2323
2424
25−data Compose :: (Type -> Type) -> (Type -> Exp Type) -> Type -> Exp Type
26−type instance Eval (Compose f g a) = f (Eval (g a))
25+data Id :: a -> Exp a
26+type instance Eval (Id a) = a
src/Rel8/Generic/Construction.hs+146−165
@@ -2,9 +2,6 @@
22{-# language ConstraintKinds #-}
33{-# language DataKinds #-}
44{-# language FlexibleContexts #-}
5−{-# language FlexibleInstances #-}
6−{-# language LambdaCase #-}
7−{-# language MultiParamTypeClasses #-}
85{-# language NamedFieldPuns #-}
96{-# language ScopedTypeVariables #-}
107{-# language StandaloneKindSignatures #-}
@@ -28,18 +25,17 @@ where
2825import Data.Bifunctor ( first )
2926import Data.Kind ( Constraint, Type )
3027import Data.List.NonEmpty ( NonEmpty( (:|) ) )
31−import Data.Type.Equality ( (:~:)( Refl ) )
3228import GHC.TypeLits ( Symbol )
3329import Prelude
3430
3531-- rel8
36−import Rel8.Aggregate ( Col( A ), Aggregate( Aggregate ) )
37−import Rel8.Expr ( Col( E ), Expr )
32+import Rel8.Aggregate ( Aggregate( Aggregate ) )
33+import Rel8.Expr ( Expr )
3834import Rel8.Expr.Aggregate ( groupByExpr )
3935import Rel8.Expr.Eq ( (==.) )
4036import Rel8.Expr.Null ( nullify, snull, unsafeUnnullify )
4137import Rel8.Expr.Serialize ( litExpr )
42−import Rel8.FCF ( Eval, Exp )
38+import Rel8.FCF ( Eval, Exp, Id )
4339import Rel8.Generic.Construction.ADT
4440 ( GConstructorADT, GMakeableADT, gmakeADT
4541 , GConstructableADT
@@ -59,18 +55,16 @@ import Rel8.Kind.Algebra
5955 , KnownAlgebra, algebraSing
6056 )
6157import qualified Rel8.Kind.Algebra as K
62−import Rel8.Schema.Context.Nullify ( runTag )
58+import Rel8.Schema.Context.Nullify ( sguard, snullify )
6359import Rel8.Schema.HTable ( HTable )
64−import Rel8.Schema.HTable.Identity ( HIdentity( HType ) )
60+import Rel8.Schema.HTable.Identity ( HIdentity( HIdentity ) )
6561import qualified Rel8.Schema.Kind as K
66−import Rel8.Schema.Name ( Col( N ), Name( Name ) )
62+import Rel8.Schema.Name ( Name( Name ) )
6763import Rel8.Schema.Null ( Nullity( Null, NotNull ) )
68−import Rel8.Schema.Spec ( SSpec( SSpec, nullity, info ) )
69−import Rel8.Schema.Reify ( Col( Reify ), Reify, hreify, hunreify )
70−import Rel8.Schema.Result ( Result )
64+import Rel8.Schema.Spec ( Spec( Spec, nullity, info ) )
7165import Rel8.Table
72− ( TTable, TColumns, TUnreify
73− , Table, fromColumns, toColumns, reify, unreify
66+ ( TTable, TColumns
67+ , Table, fromColumns, toColumns
7468 )
7569import Rel8.Table.Bool ( case_ )
7670import Rel8.Type.Tag ( Tag )
@@ -79,10 +73,10 @@ import Rel8.Type.Tag ( Tag )
7973type GGBuildable :: K.Algebra -> Symbol -> (K.Context -> Exp (Type -> Type)) -> Constraint
8074type GGBuildable algebra name rep =
8175 ( KnownAlgebra algebra
82− , Eval (GGColumns algebra TColumns (Eval (rep (Reify Aggregate)))) ~ Eval (GGColumns algebra TColumns (Eval (rep (Reify Result))))
83− , Eval (GGColumns algebra TColumns (Eval (rep (Reify Expr)))) ~ Eval (GGColumns algebra TColumns (Eval (rep (Reify Result))))
84− , Eval (GGColumns algebra TColumns (Eval (rep (Reify Name)))) ~ Eval (GGColumns algebra TColumns (Eval (rep (Reify Result))))
85− , HTable (Eval (GGColumns algebra TColumns (Eval (rep (Reify Result)))))
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))))
8680 , GGBuildable' algebra name rep
8781 )
8882
@@ -90,65 +84,63 @@ type GGBuildable algebra name rep =
9084type GGBuildable' :: K.Algebra -> Symbol -> (K.Context -> Exp (Type -> Type)) -> Constraint
9185type family GGBuildable' algebra name rep where
9286 GGBuildable' 'K.Product name rep =
93− ( name ~ GConstructor (Eval (rep (Reify Expr)))
94− , Representable TUnreify (Eval (rep (Reify Expr)))
95− , GConstructable (TTable (Reify Expr)) TColumns TUnreify (Col (Reify Expr)) (Eval (rep (Reify Expr)))
87+ ( name ~ GConstructor (Eval (rep Expr))
88+ , Representable Id (Eval (rep Expr))
89+ , GConstructable (TTable Expr) TColumns Id Expr (Eval (rep Expr))
9690 )
9791 GGBuildable' 'K.Sum name rep =
98− ( Representable TUnreify (GConstructorADT name (Eval (rep (Reify Expr))))
99− , GMakeableADT (TTable (Reify Expr)) TColumns TUnreify (Col (Reify Expr)) name (Eval (rep (Reify Expr)))
92+ ( Representable Id (GConstructorADT name (Eval (rep Expr)))
93+ , GMakeableADT (TTable Expr) TColumns Id Expr name (Eval (rep Expr))
10094 )
10195
10296
10397type GGBuild :: K.Algebra -> Symbol -> (K.Context -> Exp (Type -> Type)) -> Type -> Type
10498type family GGBuild algebra name rep r where
10599 GGBuild 'K.Product _name rep r =
106− GConstruct TUnreify (Eval (rep (Reify Expr))) r
100+ GConstruct Id (Eval (rep Expr)) r
107101 GGBuild 'K.Sum name rep r =
108− GConstruct TUnreify (GConstructorADT name (Eval (rep (Reify Expr)))) r
102+ GConstruct Id (GConstructorADT name (Eval (rep Expr))) r
109103
110104
111105ggbuild :: forall algebra name rep a. GGBuildable algebra name rep
112− => (Eval (GGColumns algebra TColumns (Eval (rep (Reify Result)))) (Col Expr) -> a)
106+ => (Eval (GGColumns algebra TColumns (Eval (rep Expr))) Expr -> a)
113107 -> GGBuild algebra name rep a
114108ggbuild gfromColumns = case algebraSing @algebra of
115109 SProduct ->
116− gtabulate @TUnreify @(Eval (rep (Reify Expr))) @a $
110+ gtabulate @Id @(Eval (rep Expr)) @a $
117111 gfromColumns .
118− hunreify .
119112 gconstruct
120− @(TTable (Reify Expr))
113+ @(TTable Expr)
121114 @TColumns
122− @TUnreify
123− @(Col (Reify Expr))
124− @(Eval (rep (Reify Expr)))
125− (\(_ :: proxy x) -> toColumns . reify @_ @x Refl)
115+ @Id
116+ @Expr
117+ @(Eval (rep Expr))
118+ (const toColumns)
126119 SSum ->
127− gtabulate @TUnreify @(GConstructorADT name (Eval (rep (Reify Expr)))) @a $
120+ gtabulate @Id @(GConstructorADT name (Eval (rep Expr))) @a $
128121 gfromColumns .
129− hunreify .
130122 gmakeADT
131− @(TTable (Reify Expr))
123+ @(TTable Expr)
132124 @TColumns
133− @TUnreify
134− @(Col (Reify Expr))
125+ @Id
126+ @Expr
135127 @name
136− @(Eval (rep (Reify Expr)))
137− (\(_ :: proxy x) -> toColumns . reify @_ @x Refl)
138− (\SSpec {info} -> Reify (E (snull info)))
139− (\SSpec {nullity} -> case nullity of
128+ @(Eval (rep Expr))
129+ (const toColumns)
130+ (\Spec {info} -> snull info)
131+ (\Spec {nullity} -> case nullity of
140132 Null -> id
141− NotNull -> \(Reify (E a)) -> Reify (E (nullify a)))
142− (HType . Reify . E . litExpr)
133+ NotNull -> nullify)
134+ (HIdentity . litExpr)
143135
144136
145137type GGConstructable :: K.Algebra -> (K.Context -> Exp (Type -> Type)) -> Constraint
146138type GGConstructable algebra rep =
147139 ( KnownAlgebra algebra
148− , Eval (GGColumns algebra TColumns (Eval (rep (Reify Aggregate)))) ~ Eval (GGColumns algebra TColumns (Eval (rep (Reify Result))))
149− , Eval (GGColumns algebra TColumns (Eval (rep (Reify Expr)))) ~ Eval (GGColumns algebra TColumns (Eval (rep (Reify Result))))
150− , Eval (GGColumns algebra TColumns (Eval (rep (Reify Name)))) ~ Eval (GGColumns algebra TColumns (Eval (rep (Reify Result))))
151− , HTable (Eval (GGColumns algebra TColumns (Eval (rep (Reify Result)))))
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))))
152144 , GGConstructable' algebra rep
153145 )
154146
@@ -156,105 +148,100 @@ type GGConstructable algebra rep =
156148type GGConstructable' :: K.Algebra -> (K.Context -> Exp (Type -> Type)) -> Constraint
157149type family GGConstructable' algebra rep where
158150 GGConstructable' 'K.Product rep =
159− ( Representable TUnreify (Eval (rep (Reify Aggregate)))
160− , Representable TUnreify (Eval (rep (Reify Expr)))
161− , Representable TUnreify (Eval (rep (Reify Name)))
162− , GConstructable (TTable (Reify Aggregate)) TColumns TUnreify (Col (Reify Aggregate)) (Eval (rep (Reify Aggregate)))
163− , GConstructable (TTable (Reify Expr)) TColumns TUnreify (Col (Reify Expr)) (Eval (rep (Reify Expr)))
164− , GConstructable (TTable (Reify Name)) TColumns TUnreify (Col (Reify Name)) (Eval (rep (Reify Name)))
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))
165157 )
166158 GGConstructable' 'K.Sum rep =
167− ( RepresentableConstructors TUnreify (Eval (rep (Reify Expr)))
168− , RepresentableFields TUnreify (Eval (rep (Reify Aggregate)))
169− , RepresentableFields TUnreify (Eval (rep (Reify Expr)))
170− , RepresentableFields TUnreify (Eval (rep (Reify Name)))
171− , Functor (GConstructors TUnreify (Eval (rep (Reify Expr))))
172− , GConstructableADT (TTable (Reify Aggregate)) TColumns TUnreify (Col (Reify Aggregate)) (Eval (rep (Reify Aggregate)))
173− , GConstructableADT (TTable (Reify Expr)) TColumns TUnreify (Col (Reify Expr)) (Eval (rep (Reify Expr)))
174− , GConstructableADT (TTable (Reify Name)) TColumns TUnreify (Col (Reify Name)) (Eval (rep (Reify Name)))
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))
175167 )
176168
177169
178170type GGConstruct :: K.Algebra -> (K.Context -> Exp (Type -> Type)) -> Type -> Type
179171type family GGConstruct algebra rep r where
180− GGConstruct 'K.Product rep r =
181− GConstruct TUnreify (Eval (rep (Reify Expr))) r -> r
182− GGConstruct 'K.Sum rep r =
183− GConstructADT TUnreify (Eval (rep (Reify Expr))) r r
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
184174
185175
186176ggconstruct :: forall algebra rep a. GGConstructable algebra rep
187− => (Eval (GGColumns algebra TColumns (Eval (rep (Reify Result)))) (Col Expr) -> a)
177+ => (Eval (GGColumns algebra TColumns (Eval (rep Expr))) Expr -> a)
188178 -> GGConstruct algebra rep a -> a
189179ggconstruct gfromColumns f = case algebraSing @algebra of
190180 SProduct ->
191181 f $
192− gtabulate @TUnreify @(Eval (rep (Reify Expr))) @a $
182+ gtabulate @Id @(Eval (rep Expr)) @a $
193183 gfromColumns .
194− hunreify .
195184 gconstruct
196− @(TTable (Reify Expr))
185+ @(TTable Expr)
197186 @TColumns
198− @TUnreify
199− @(Col (Reify Expr))
200− @(Eval (rep (Reify Expr)))
201− (\(_ :: proxy x) -> toColumns . reify @_ @x Refl)
187+ @Id
188+ @Expr
189+ @(Eval (rep Expr))
190+ (const toColumns)
202191 SSum ->
203− gcindex @TUnreify @(Eval (rep (Reify Expr))) @a f $
204− fmap (gfromColumns . hunreify) $
192+ gcindex @Id @(Eval (rep Expr)) @a f $
193+ fmap gfromColumns $
205194 gconstructADT
206− @(TTable (Reify Expr))
195+ @(TTable Expr)
207196 @TColumns
208− @TUnreify
209− @(Col (Reify Expr))
210− @(Eval (rep (Reify Expr)))
211− (\(_ :: proxy x) -> toColumns . reify @_ @x Refl)
212− (\SSpec {info} -> Reify (E (snull info)))
213− (\SSpec {nullity} -> case nullity of
197+ @Id
198+ @Expr
199+ @(Eval (rep Expr))
200+ (const toColumns)
201+ (\Spec {info} -> snull info)
202+ (\Spec {nullity} -> case nullity of
214203 Null -> id
215− NotNull -> \(Reify (E a)) -> Reify (E (nullify a)))
216− (HType . Reify . E . litExpr)
204+ NotNull -> nullify)
205+ (HIdentity . litExpr)
217206
218207
219208type GGDeconstruct :: K.Algebra -> (K.Context -> Exp (Type -> Type)) -> Type -> Type -> Type
220209type family GGDeconstruct algebra rep a r where
221210 GGDeconstruct 'K.Product rep a r =
222− GConstruct TUnreify (Eval (rep (Reify Expr))) r -> a -> r
211+ GConstruct Id (Eval (rep Expr)) r -> a -> r
223212 GGDeconstruct 'K.Sum rep a r =
224− GConstructADT TUnreify (Eval (rep (Reify Expr))) r (a -> r)
213+ GConstructADT Id (Eval (rep Expr)) r (a -> r)
225214
226215
227216ggdeconstruct :: forall algebra rep a r. (GGConstructable algebra rep, Table Expr r)
228− => (a -> Eval (GGColumns algebra TColumns (Eval (rep (Reify Result)))) (Col Expr))
217+ => (a -> Eval (GGColumns algebra TColumns (Eval (rep Expr))) Expr)
229218 -> GGDeconstruct algebra rep a r
230219ggdeconstruct gtoColumns = case algebraSing @algebra of
231220 SProduct -> \build ->
232− gindex @TUnreify @(Eval (rep (Reify Expr))) @r build .
221+ gindex @Id @(Eval (rep Expr)) @r build .
233222 gdeconstruct
234− @(TTable (Reify Expr))
223+ @(TTable Expr)
235224 @TColumns
236− @TUnreify
237− @(Col (Reify Expr))
238− @(Eval (rep (Reify Expr)))
239− (\(_ :: proxy x) -> unreify @_ @x Refl . fromColumns) .
240− hreify .
225+ @Id
226+ @Expr
227+ @(Eval (rep Expr))
228+ (const fromColumns) .
241229 gtoColumns
242230 SSum ->
243− gctabulate @TUnreify @(Eval (rep (Reify Expr))) @r @(a -> r) $ \constructors as ->
231+ gctabulate @Id @(Eval (rep Expr)) @r @(a -> r) $ \constructors as ->
244232 let
245− (HType (Reify (E tag)), cases) =
233+ (HIdentity tag, cases) =
246234 gdeconstructADT
247− @(TTable (Reify Expr))
235+ @(TTable Expr)
248236 @TColumns
249− @TUnreify
250− @(Col (Reify Expr))
251− @(Eval (rep (Reify Expr)))
252− (\(_ :: proxy x) -> unreify @_ @x Refl . fromColumns)
253− (\SSpec {nullity} -> case nullity of
237+ @Id
238+ @Expr
239+ @(Eval (rep Expr))
240+ (const fromColumns)
241+ (\Spec {nullity} -> case nullity of
254242 Null -> id
255− NotNull -> \(Reify (E a)) -> Reify (E (unsafeUnnullify a)))
243+ NotNull -> unsafeUnnullify)
256244 constructors $
257− hreify $
258245 gtoColumns as
259246 in
260247 case cases of
@@ -264,108 +251,102 @@ ggdeconstruct gtoColumns = case algebraSing @algebra of
264251
265252type GGName :: K.Algebra -> (K.Context -> Exp (Type -> Type)) -> Type -> Type
266253type family GGName algebra rep a where
267− GGName 'K.Product rep a = GConstruct TUnreify (Eval (rep (Reify Name))) a
268− GGName 'K.Sum rep a = Name Tag -> GBuildADT TUnreify (Eval (rep (Reify Name))) a
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
269256
270257
271258ggname :: forall algebra rep a. GGConstructable algebra rep
272− => (Eval (GGColumns algebra TColumns (Eval (rep (Reify Result)))) (Col Name) -> a)
259+ => (Eval (GGColumns algebra TColumns (Eval (rep Expr))) Name -> a)
273260 -> GGName algebra rep a
274261ggname gfromColumns = case algebraSing @algebra of
275262 SProduct ->
276− gtabulate @TUnreify @(Eval (rep (Reify Name))) @a $
263+ gtabulate @Id @(Eval (rep Name)) @a $
277264 gfromColumns .
278− hunreify .
279265 gconstruct
280− @(TTable (Reify Name))
266+ @(TTable Name)
281267 @TColumns
282− @TUnreify
283− @(Col (Reify Name))
284− @(Eval (rep (Reify Name)))
285− (\(_ :: proxy x) -> toColumns . reify @_ @x Refl)
268+ @Id
269+ @Name
270+ @(Eval (rep Name))
271+ (const toColumns)
286272 SSum -> \tag ->
287− gftabulate @TUnreify @(Eval (rep (Reify Name))) @a $
273+ gftabulate @Id @(Eval (rep Name)) @a $
288274 gfromColumns .
289− hunreify .
290275 gbuildADT
291− @(TTable (Reify Name))
276+ @(TTable Name)
292277 @TColumns
293− @TUnreify
294− @(Col (Reify Name))
295− @(Eval (rep (Reify Name)))
296− (\(_ :: proxy x) -> toColumns . reify @_ @x Refl)
297− (\_ _ (Reify (N (Name a))) -> Reify (N (Name a)))
298− (HType (Reify (N tag)))
278+ @Id
279+ @Name
280+ @(Eval (rep Name))
281+ (const toColumns)
282+ (\_ _ (Name a) -> Name a)
283+ (HIdentity tag)
299284
300285
301286type GGAggregate :: K.Algebra -> (K.Context -> Exp (Type -> Type)) -> Type -> Type
302287type family GGAggregate algebra rep r where
303288 GGAggregate 'K.Product rep r =
304− GConstruct TUnreify (Eval (rep (Reify Aggregate))) r ->
305− GConstruct TUnreify (Eval (rep (Reify Expr))) r
289+ GConstruct Id (Eval (rep Aggregate)) r ->
290+ GConstruct Id (Eval (rep Expr)) r
306291 GGAggregate 'K.Sum rep r =
307− GBuildADT TUnreify (Eval (rep (Reify Aggregate))) r ->
308− GBuildADT TUnreify (Eval (rep (Reify Expr))) r
292+ GBuildADT Id (Eval (rep Aggregate)) r ->
293+ GBuildADT Id (Eval (rep Expr)) r
309294
310295
311296ggaggregate :: forall algebra rep exprs agg. GGConstructable algebra rep
312− => (Eval (GGColumns algebra TColumns (Eval (rep (Reify Result)))) (Col Aggregate) -> agg)
313− -> (exprs -> Eval (GGColumns algebra TColumns (Eval (rep (Reify Result)))) (Col Expr))
297+ => (Eval (GGColumns algebra TColumns (Eval (rep Expr))) Aggregate -> agg)
298+ -> (exprs -> Eval (GGColumns algebra TColumns (Eval (rep Expr))) Expr)
314299 -> GGAggregate algebra rep agg -> exprs -> agg
315300ggaggregate gfromColumns gtoColumns agg es = case algebraSing @algebra of
316301 SProduct -> flip f exprs $
317302 gfromColumns .
318− hunreify .
319303 gconstruct
320− @(TTable (Reify Aggregate))
304+ @(TTable Aggregate)
321305 @TColumns
322− @TUnreify
323− @(Col (Reify Aggregate))
324− @(Eval (rep (Reify Aggregate)))
325− (\(_ :: proxy x) -> toColumns . reify @_ @x Refl)
306+ @Id
307+ @Aggregate
308+ @(Eval (rep Aggregate))
309+ (const toColumns)
326310 where
327311 f =
328− gindex @TUnreify @(Eval (rep (Reify Expr))) @agg .
312+ gindex @Id @(Eval (rep Expr)) @agg .
329313 agg .
330− gtabulate @TUnreify @(Eval (rep (Reify Aggregate))) @agg
314+ gtabulate @Id @(Eval (rep Aggregate)) @agg
331315 exprs =
332316 gdeconstruct
333− @(TTable (Reify Expr))
317+ @(TTable Expr)
334318 @TColumns
335− @TUnreify
336− @(Col (Reify Expr))
337− @(Eval (rep (Reify Expr)))
338− (\(_ :: proxy x) -> unreify @_ @x Refl . fromColumns) $
339− hreify $
319+ @Id
320+ @Expr
321+ @(Eval (rep Expr))
322+ (const fromColumns) $
340323 gtoColumns es
341324 SSum -> flip f exprs $
342325 gfromColumns .
343− hunreify .
344326 gbuildADT
345− @(TTable (Reify Aggregate))
327+ @(TTable Aggregate)
346328 @TColumns
347− @TUnreify
348− @(Col (Reify Aggregate))
349− @(Eval (rep (Reify Aggregate)))
350− (\(_ :: proxy x) -> toColumns . reify @_ @x Refl)
351− (\tag' SSpec {nullity} (Reify (A (Aggregate a))) ->
352− Reify $ A $ Aggregate $ runTag nullity (tag ==. litExpr tag') <$> a)
353− (HType (Reify (A (groupByExpr tag))))
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))
354336 where
355337 f =
356− gfindex @TUnreify @(Eval (rep (Reify Expr))) @agg .
338+ gfindex @Id @(Eval (rep Expr)) @agg .
357339 agg .
358− gftabulate @TUnreify @(Eval (rep (Reify Aggregate))) @agg
359− (HType (Reify (E tag)), exprs) =
340+ gftabulate @Id @(Eval (rep Aggregate)) @agg
341+ (HIdentity tag, exprs) =
360342 gunbuildADT
361− @(TTable (Reify Expr))
343+ @(TTable Expr)
362344 @TColumns
363− @TUnreify
364− @(Col (Reify Expr))
365− @(Eval (rep (Reify Expr)))
366− (\(_ :: proxy x) -> unreify @_ @x Refl . fromColumns)
367− (\SSpec {nullity} -> case nullity of
345+ @Id
346+ @Expr
347+ @(Eval (rep Expr))
348+ (const fromColumns)
349+ (\Spec {nullity} -> case nullity of
368350 Null -> id
369− NotNull -> \(Reify (E a)) -> Reify (E (unsafeUnnullify a))) $
370− hreify $
351+ NotNull -> unsafeUnnullify) $
371352 gtoColumns es
src/Rel8/Generic/Construction/ADT.hs+32−47
@@ -1,6 +1,7 @@
11{-# language AllowAmbiguousTypes #-}
22{-# language BlockArguments #-}
33{-# language DataKinds #-}
4+{-# language FlexibleContexts #-}
45{-# language FlexibleInstances #-}
56{-# language MultiParamTypeClasses #-}
67{-# language RankNTypes #-}
@@ -48,14 +49,13 @@ import Rel8.Generic.Construction.Record
4849 )
4950import Rel8.Generic.Table.ADT ( GColumnsADT, GColumnsADT' )
5051import Rel8.Generic.Table.Record ( GColumns )
51−import Rel8.Schema.Context.Label ( HLabelable, hlabeler, hunlabeler )
5252import Rel8.Schema.HTable ( HTable )
53−import Rel8.Schema.HTable.Identity ( HType )
53+import Rel8.Schema.HTable.Identity ( HIdentity )
5454import Rel8.Schema.HTable.Label ( HLabel, hlabel, hunlabel )
5555import Rel8.Schema.HTable.Nullify ( HNullify, hnulls, hnullify, hunnullify )
5656import Rel8.Schema.HTable.Product ( HProduct( HProduct ) )
5757import Rel8.Schema.Null ( Nullify )
58−import Rel8.Schema.Spec ( Spec( Spec ), SSpec )
58+import Rel8.Schema.Spec ( Spec )
5959import qualified Rel8.Schema.Kind as K
6060import Rel8.Type.Tag ( Tag( Tag ) )
6161
@@ -63,24 +63,16 @@ import Rel8.Type.Tag ( Tag( Tag ) )
6363import Data.Text ( pack )
6464
6565
66−type Null :: K.HContext -> Type
67−type Null context = forall labels a. ()
68− => SSpec ('Spec labels a)
69− -> context ('Spec labels (Nullify a))
66+type Null :: K.Context -> Type
67+type Null context = forall a. Spec a -> context (Nullify a)
7068
7169
72−type Nullifier :: K.HContext -> Type
73−type Nullifier context = forall labels a. ()
74− => SSpec ('Spec labels a)
75− -> context ('Spec labels a)
76− -> context ('Spec labels (Nullify a))
70+type Nullifier :: K.Context -> Type
71+type Nullifier context = forall a. Spec a -> context a -> context (Nullify a)
7772
7873
79−type Unnullifier :: K.HContext -> Type
80−type Unnullifier context = forall labels a. ()
81− => SSpec ('Spec labels a)
82− -> context ('Spec labels (Nullify a))
83− -> context ('Spec labels a)
74+type Unnullifier :: K.Context -> Type
75+type Unnullifier context = forall a. Spec a -> context (Nullify a) -> context a
8476
8577
8678type NoConstructor :: Symbol -> Symbol -> ErrorMessage
@@ -189,12 +181,12 @@ type GConstructableADT
189181 :: (Type -> Exp Constraint)
190182 -> (Type -> Exp K.HTable)
191183 -> (Type -> Exp Type)
192− -> K.HContext -> (Type -> Type) -> Constraint
184+ -> K.Context -> (Type -> Type) -> Constraint
193185class GConstructableADT _Table _Columns f context rep where
194186 gbuildADT :: ()
195187 => ToColumns _Table _Columns f context
196188 -> (Tag -> Nullifier context)
197− -> HType Tag context
189+ -> HIdentity Tag context
198190 -> GFieldsADT f rep
199191 -> GColumnsADT _Columns rep context
200192
@@ -202,13 +194,13 @@ class GConstructableADT _Table _Columns f context rep where
202194 => FromColumns _Table _Columns f context
203195 -> Unnullifier context
204196 -> GColumnsADT _Columns rep context
205− -> (HType Tag context, GFieldsADT f rep)
197+ -> (HIdentity Tag context, GFieldsADT f rep)
206198
207199 gconstructADT :: ()
208200 => ToColumns _Table _Columns f context
209201 -> Null context
210202 -> Nullifier context
211− -> (Tag -> HType Tag context)
203+ -> (Tag -> HIdentity Tag context)
212204 -> GConstructors f rep (GColumnsADT _Columns rep context)
213205
214206 gdeconstructADT :: ()
@@ -216,30 +208,29 @@ class GConstructableADT _Table _Columns f context rep where
216208 -> Unnullifier context
217209 -> GConstructors f rep r
218210 -> GColumnsADT _Columns rep context
219− -> (HType Tag context, NonEmpty (Tag, r))
211+ -> (HIdentity Tag context, NonEmpty (Tag, r))
220212
221213
222214instance
223− ( htable ~ HLabel "tag" (HType Tag)
215+ ( htable ~ HLabel "tag" (HIdentity Tag)
224216 , GConstructableADT' _Table _Columns f context htable rep
225− , HLabelable context
226217 )
227218 => GConstructableADT _Table _Columns f context (M1 D meta rep)
228219 where
229220 gbuildADT toColumns nullifier =
230221 gbuildADT' @_Table @_Columns @f @context @htable @rep toColumns nullifier .
231− hlabel hlabeler
222+ hlabel
232223
233224 gunbuildADT fromColumns unnullifier =
234− first (hunlabel hunlabeler) .
225+ first hunlabel .
235226 gunbuildADT' @_Table @_Columns @f @context @htable @rep fromColumns unnullifier
236227
237228 gconstructADT toColumns null nullifier mk =
238229 gconstructADT' @_Table @_Columns @f @context @htable @rep toColumns null nullifier
239− (hlabel hlabeler . mk)
230+ (hlabel . mk)
240231
241232 gdeconstructADT fromColumns unnullifier cases =
242− first (hunlabel hunlabeler) .
233+ first hunlabel .
243234 gdeconstructADT' @_Table @_Columns @f @context @htable @rep fromColumns unnullifier cases
244235
245236
@@ -247,7 +238,7 @@ type GConstructableADT'
247238 :: (Type -> Exp Constraint)
248239 -> (Type -> Exp K.HTable)
249240 -> (Type -> Exp Type)
250− -> K.HContext -> K.HTable -> (Type -> Type) -> Constraint
241+ -> K.Context -> K.HTable -> (Type -> Type) -> Constraint
251242class GConstructableADT' _Table _Columns f context htable rep where
252243 gbuildADT' :: ()
253244 => ToColumns _Table _Columns f context
@@ -334,7 +325,6 @@ instance {-# OVERLAPPABLE #-}
334325 ( HTable (GColumns _Columns rep)
335326 , KnownSymbol label
336327 , meta ~ 'MetaCons label _fixity _isRecord
337− , HLabelable context
338328 , GConstructable _Table _Columns f context rep
339329 , GColumnsADT' _Columns htable (M1 C meta rep) ~
340330 HProduct htable (HLabel label (HNullify (GColumns _Columns rep)))
@@ -343,7 +333,7 @@ instance {-# OVERLAPPABLE #-}
343333 where
344334 gbuildADT' toColumns nullifier htable =
345335 HProduct htable .
346− hlabel hlabeler .
336+ hlabel .
347337 hnullify (nullifier tag) .
348338 gconstruct @_Table @_Columns @f @context @rep toColumns
349339 where
@@ -354,13 +344,13 @@ instance {-# OVERLAPPABLE #-}
354344 , gdeconstruct @_Table @_Columns @f @context @rep fromColumns $
355345 runIdentity $
356346 hunnullify (\spec -> pure . unnullifier spec) $
357− hunlabel hunlabeler
347+ hunlabel
358348 a
359349 )
360350
361351 gconstructADT' toColumns _ nullifier mk =
362352 HProduct htable .
363− hlabel hlabeler .
353+ hlabel .
364354 hnullify nullifier .
365355 gconstruct @_Table @_Columns @f @context @rep toColumns
366356 where
@@ -375,35 +365,34 @@ instance {-# OVERLAPPABLE #-}
375365 a = gdeconstruct @_Table @_Columns @f @context @rep fromColumns $
376366 runIdentity $
377367 hunnullify (\spec -> pure . unnullifier spec) $
378− hunlabel hunlabeler
368+ hunlabel
379369 columns
380370 tag = Tag $ pack $ symbolVal (Proxy @label)
381371
382− gfill null htable = HProduct htable (hlabel hlabeler (hnulls null))
372+ gfill null htable = HProduct htable (hlabel (hnulls null))
383373
384374
385375type GMakeableADT
386376 :: (Type -> Exp Constraint)
387377 -> (Type -> Exp K.HTable)
388378 -> (Type -> Exp Type)
389− -> K.HContext -> Symbol -> (Type -> Type) -> Constraint
379+ -> K.Context -> Symbol -> (Type -> Type) -> Constraint
390380class GMakeableADT _Table _Columns f context name rep where
391381 gmakeADT :: ()
392382 => ToColumns _Table _Columns f context
393383 -> Null context
394384 -> Nullifier context
395− -> (Tag -> HType Tag context)
385+ -> (Tag -> HIdentity Tag context)
396386 -> GFields f (GConstructorADT name rep)
397387 -> GColumnsADT _Columns rep context
398388
399389
400390instance
401− ( htable ~ HLabel "tag" (HType Tag)
391+ ( htable ~ HLabel "tag" (HIdentity Tag)
402392 , meta ~ 'MetaData datatype _module _package _newtype
403393 , fallback ~ TypeError (NoConstructor datatype name)
404394 , fields ~ GFields f (GConstructorADT' name rep fallback)
405395 , GMakeableADT' _Table _Columns f context htable name rep fields
406− , HLabelable context
407396 , KnownSymbol name
408397 )
409398 => GMakeableADT _Table _Columns f context name (M1 D meta rep)
@@ -414,14 +403,14 @@ instance
414403 toColumns null nullifier htable
415404 where
416405 tag = Tag $ pack $ symbolVal (Proxy @name)
417− htable = hlabel hlabeler (wrap tag)
406+ htable = hlabel (wrap tag)
418407
419408
420409type GMakeableADT'
421410 :: (Type -> Exp Constraint)
422411 -> (Type -> Exp K.HTable)
423412 -> (Type -> Exp Type)
424− -> K.HContext -> K.HTable -> Symbol -> (Type -> Type) -> Type -> Constraint
413+ -> K.Context -> K.HTable -> Symbol -> (Type -> Type) -> Type -> Constraint
425414class GMakeableADT' _Table _Columns f context htable name rep fields where
426415 gmakeADT' :: ()
427416 => ToColumns _Table _Columns f context
@@ -462,8 +451,6 @@ instance {-# OVERLAPS #-}
462451
463452instance {-# OVERLAPS #-}
464453 ( HTable (GColumns _Columns rep)
465− , KnownSymbol name
466− , HLabelable context
467454 , GConstructable _Table _Columns f context rep
468455 , fields ~ GFields f rep
469456 , GColumnsADT' _Columns htable (M1 C ('MetaCons name _fixity _isRecord) rep) ~
@@ -473,15 +460,13 @@ instance {-# OVERLAPS #-}
473460 where
474461 gmakeADT' toColumns _ nullifier htable =
475462 HProduct htable .
476− hlabel hlabeler .
463+ hlabel .
477464 hnullify nullifier .
478465 gconstruct @_Table @_Columns @f @context @rep toColumns
479466
480467
481468instance {-# OVERLAPPABLE #-}
482469 ( HTable (GColumns _Columns rep)
483− , KnownSymbol label
484− , HLabelable context
485470 , GColumnsADT' _Columns htable (M1 C ('MetaCons label _fixity _isRecord) rep) ~
486471 HProduct htable (HLabel label (HNullify (GColumns _Columns rep)))
487472 )
@@ -489,5 +474,5 @@ instance {-# OVERLAPPABLE #-}
489474 where
490475 gmakeADT' _ null _ htable _ =
491476 HProduct htable $
492− hlabel hlabeler $
477+ hlabel $
493478 hnulls null
src/Rel8/Generic/Construction/Record.hs+6−11
@@ -27,15 +27,13 @@ import GHC.Generics
2727 )
2828import GHC.TypeLits
2929 ( ErrorMessage( (:<>:), Text ), TypeError
30− , Symbol, KnownSymbol
30+ , Symbol
3131 )
3232import Prelude
3333
3434-- rel8
3535import Rel8.FCF ( Eval, Exp )
3636import Rel8.Generic.Table.Record ( GColumns )
37−import Rel8.Schema.Context.Label ( HLabelable, hlabeler, hunlabeler )
38−import Rel8.Schema.HTable ( HTable )
3937import Rel8.Schema.HTable.Label ( hlabel, hunlabel )
4038import Rel8.Schema.HTable.Product ( HProduct( HProduct ) )
4139import qualified Rel8.Schema.Kind as K
@@ -45,7 +43,7 @@ type FromColumns
4543 :: (Type -> Exp Constraint)
4644 -> (Type -> Exp K.HTable)
4745 -> (Type -> Exp Type)
48− -> K.HContext
46+ -> K.Context
4947 -> Type
5048type FromColumns _Table _Columns f context = forall proxy x.
5149 Eval (_Table x) => proxy x -> Eval (_Columns x) context -> Eval (f x)
@@ -55,7 +53,7 @@ type ToColumns
5553 :: (Type -> Exp Constraint)
5654 -> (Type -> Exp K.HTable)
5755 -> (Type -> Exp Type)
58− -> K.HContext
56+ -> K.Context
5957 -> Type
6058type ToColumns _Table _Columns f context = forall proxy x.
6159 Eval (_Table x) => proxy x -> Eval (f x) -> Eval (_Columns x) context
@@ -119,7 +117,7 @@ type GConstructable
119117 :: (Type -> Exp Constraint)
120118 -> (Type -> Exp K.HTable)
121119 -> (Type -> Exp Type)
122− -> K.HContext -> (Type -> Type) -> Constraint
120+ -> K.Context -> (Type -> Type) -> Constraint
123121class GConstructable _Table _Columns f context rep where
124122 gconstruct :: ()
125123 => ToColumns _Table _Columns f context
@@ -162,12 +160,9 @@ instance
162160
163161instance
164162 ( Eval (_Table a)
165− , HTable (Eval (_Columns a))
166− , HLabelable context
167− , KnownSymbol label
168163 , meta ~ 'MetaSel ('Just label) _su _ss _ds
169164 )
170165 => GConstructable _Table _Columns f context (M1 S meta (K1 i a))
171166 where
172− gconstruct toColumns = hlabel hlabeler . toColumns (Proxy @a)
173− gdeconstruct fromColumns = fromColumns (Proxy @a) . hunlabel hunlabeler
167+ gconstruct toColumns = hlabel . toColumns (Proxy @a)
168+ gdeconstruct fromColumns = fromColumns (Proxy @a) . hunlabel
src/Rel8/Generic/Map.hs+20−64
@@ -1,26 +1,19 @@
1−{-# language AllowAmbiguousTypes #-}
21{-# language DataKinds #-}
3−{-# language EmptyCase #-}
4−{-# language FlexibleInstances #-}
5−{-# language LambdaCase #-}
6−{-# language MultiParamTypeClasses #-}
7−{-# language RankNTypes #-}
8−{-# language ScopedTypeVariables #-}
92{-# language StandaloneKindSignatures #-}
10−{-# language TypeApplications #-}
113{-# language TypeFamilies #-}
124{-# language TypeOperators #-}
135{-# language UndecidableInstances #-}
146
157module Rel8.Generic.Map
16− ( GMap, GMappable (gmap, gunmap)
8+ ( GMap
9+ , Map
1710 )
1811where
1912
2013-- base
21−import Data.Kind ( Constraint, Type )
14+import Data.Kind ( Type )
2215import GHC.Generics
23− ( (:+:)( L1, R1 ), (:*:)( (:*:) ), K1( K1 ), M1( M1 ), U1( U1 ), V1
16+ ( (:+:), (:*:), K1, M1, U1, V1
2417 )
2518import Prelude ()
2619
@@ -38,56 +31,19 @@ type family GMap f rep where
3831 GMap f (K1 i a) = K1 i (Eval (f a))
3932
4033
41−type GMappable :: (Type -> Exp Constraint) -> (Type -> Type) -> Constraint
42−class GMappable constraint rep where
43− gmap :: ()
44− => proxy f
45− -> (forall a. Eval (constraint a) => a -> Eval (f a))
46− -> rep x
47− -> GMap f rep x
48−
49− gunmap :: ()
50− => proxy f
51− -> (forall a. Eval (constraint a) => Eval (f a) -> a)
52− -> GMap f rep x
53− -> rep x
54−
55−
56−instance GMappable constraint rep => GMappable constraint (M1 i c rep) where
57− gmap proxy f (M1 a) = M1 (gmap @constraint proxy f a)
58− gunmap proxy f (M1 a) = M1 (gunmap @constraint proxy f a)
59−
60−
61−instance GMappable constraint V1 where
62− gmap _ _ = \case
63− gunmap _ _ = \case
64−
65−
66−instance (GMappable constraint rep1, GMappable constraint rep2) =>
67− GMappable constraint (rep1 :+: rep2)
68− where
69− gmap proxy f = \case
70− L1 a -> L1 (gmap @constraint proxy f a)
71− R1 a -> R1 (gmap @constraint proxy f a)
72− gunmap proxy f = \case
73− L1 a -> L1 (gunmap @constraint proxy f a)
74− R1 a -> R1 (gunmap @constraint proxy f a)
75−
76−
77−instance GMappable constraint U1 where
78− gmap _ _ U1 = U1
79− gunmap _ _ U1 = U1
80−
81−
82−instance (GMappable constraint rep1, GMappable constraint rep2) =>
83− GMappable constraint (rep1 :*: rep2)
84− where
85− gmap proxy f (a :*: b) =
86− gmap @constraint proxy f a :*: gmap @constraint proxy f b
87− gunmap proxy f (a :*: b) =
88− gunmap @constraint proxy f a :*: gunmap @constraint proxy f b
89−
90−
91−instance Eval (constraint a) => GMappable constraint (K1 i a) where
92− gmap _ f (K1 a) = K1 (f a)
93− gunmap _ f (K1 a) = K1 (f a)
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+2
@@ -1,5 +1,6 @@
11{-# language AllowAmbiguousTypes #-}
22{-# language DataKinds #-}
3+{-# language FlexibleContexts #-}
34{-# language FlexibleInstances #-}
45{-# language MultiParamTypeClasses #-}
56{-# language PolyKinds #-}
@@ -141,6 +142,7 @@ instance {-# OVERLAPPABLE #-} Snd (Count n rep) ~ rep => Countable n rep where
141142 uncount = id
142143
143144
145+type Record :: Type -> Type
144146newtype Record a = Record
145147 { unrecord :: a
146148 }
src/Rel8/Generic/Reify.hsdeleted−24
@@ -1,24 +0,0 @@
1−{-# language StandaloneKindSignatures #-}
2−{-# language TypeFamilies #-}
3−
4−module Rel8.Generic.Reify
5− ( ARep
6− )
7−where
8−
9−-- base
10−import Data.Functor.Contravariant ( Contravariant, contramap )
11−import Data.Kind ( Type )
12−import Data.Void ( Void, absurd )
13−import GHC.Generics ( Generic, Rep, from, to )
14−import Prelude
15−
16−
17−type ARep :: (Type -> Type) -> Type
18−newtype ARep rep = ARep (rep Void)
19−
20−
21−instance (Contravariant rep, Functor rep) => Generic (ARep rep) where
22− type Rep (ARep rep) = rep
23− from (ARep a) = fmap absurd a
24− to = ARep . contramap absurd
src/Rel8/Generic/Rel8able.hs+178−72
@@ -1,13 +1,18 @@
11{-# language AllowAmbiguousTypes #-}
2+{-# language ConstraintKinds #-}
23{-# language DataKinds #-}
34{-# language DefaultSignatures #-}
45{-# language FlexibleContexts #-}
56{-# language FlexibleInstances #-}
7+{-# language LambdaCase #-}
68{-# language MultiParamTypeClasses #-}
9+{-# language PolyKinds #-}
10+{-# language QuantifiedConstraints #-}
711{-# language ScopedTypeVariables #-}
812{-# language StandaloneKindSignatures #-}
913{-# language TypeApplications #-}
10−{-# language TypeFamilies #-}
14+{-# language TypeFamilyDependencies #-}
15+{-# language TypeOperators #-}
1116{-# language UndecidableInstances #-}
1217
1318module Rel8.Generic.Rel8able
@@ -15,36 +20,39 @@ module Rel8.Generic.Rel8able
1520 , Algebra
1621 , GRep
1722 , GColumns, gfromColumns, gtoColumns
18− , greify, gunreify
19− , TUnreifyContext
23+ , GFromExprs, gfromResult, gtoResult
24+ , TSerialize, serialize, deserialize
2025 )
2126where
2227
2328-- base
29+import Data.Functor.Identity ( Identity )
2430import Data.Kind ( Constraint, Type )
25−import Data.Proxy ( Proxy( Proxy ) )
26−import Data.Type.Equality ( (:~:)( Refl ) )
31+import Data.Type.Bool ( type (&&) )
2732import GHC.Generics ( Generic, Rep, from, to )
2833import Prelude
2934
3035-- rel8
31−import Rel8.Kind.Context ( Reifiable )
32−import Rel8.FCF ( Eval, Exp )
33−import Rel8.Generic.Map ( GMap, GMappable, gmap, gunmap )
36+import Rel8.Aggregate ( Aggregate )
37+import Rel8.Expr ( Expr )
38+import Rel8.FCF ( Exp, Eval )
3439import Rel8.Generic.Record ( Record(..) )
3540import Rel8.Generic.Table ( GAlgebra )
3641import qualified Rel8.Generic.Table.Record as G
3742import qualified Rel8.Kind.Algebra as K ( Algebra(..) )
38−import Rel8.Schema.Context ( Col )
39−import Rel8.Schema.Context.Label ( Labelable )
43+import Rel8.Kind.Context ( SContext(..) )
44+import Rel8.Schema.Field ( Field )
4045import Rel8.Schema.HTable ( HTable )
4146import qualified Rel8.Schema.Kind as K
42−import Rel8.Schema.Reify ( Reify, UnwrapReify )
47+import Rel8.Schema.Name ( Name )
4348import Rel8.Schema.Result ( Result )
4449import Rel8.Table
45− ( fromColumns, toColumns, reify, unreify
46− , TTable, TColumns, TContext, TUnreify
50+ ( Table, Columns, Context, fromColumns, toColumns
51+ , FromExprs, fromResult, toResult
52+ , Transpose
53+ , TTable, TColumns
4754 )
55+import Rel8.Table.Transpose ( Transposes )
4856
4957
5058-- | The kind of 'Rel8able' types
@@ -52,6 +60,59 @@ type KRel8able :: Type
5260type KRel8able = K.Rel8able
5361
5462
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+
55116-- | This type class allows you to define custom 'Table's using higher-kinded
56117-- data types. Higher-kinded data types are data types of the pattern:
57118--
@@ -85,7 +146,7 @@ type KRel8able = K.Rel8able
85146-- [Supplying @Rel8able@ instances]
86147--
87148-- This type class should be derived generically for all table types in your
88−-- project. To do this, enable the @DeriveAnyType@ and @DeriveGeneric@ language
149+-- project. To do this, enable the @DeriveAnyClass@ and @DeriveGeneric@ language
89150-- extensions:
90151--
91152-- @
@@ -97,79 +158,124 @@ type KRel8able = K.Rel8able
97158type Rel8able :: K.Rel8able -> Constraint
98159class HTable (GColumns t) => Rel8able t where
99160 type GColumns t :: K.HTable
161+ type GFromExprs t :: Type
100162
101− gfromColumns :: (Labelable context, Reifiable context)
102− => GColumns t (Col (Reify context)) -> t (Reify context)
103−
104− gtoColumns :: (Labelable context, Reifiable context)
105− => t (Reify context) -> GColumns t (Col (Reify context))
163+ gfromColumns :: SContext context -> GColumns t context -> t context
164+ gtoColumns :: SContext context -> t context -> GColumns t context
106165
107− greify :: (Labelable context, Reifiable context)
108− => t context -> t (Reify context)
166+ gfromResult :: GColumns t Result -> GFromExprs t
167+ gtoResult :: GFromExprs t -> GColumns t Result
109168
110− gunreify :: (Labelable context, Reifiable context)
111− => t (Reify context) -> t context
112−
113− type GColumns t = G.GColumns TColumns (GRep t (Reify Result))
169+ type GColumns t = G.GColumns TColumns (GRep t Expr)
170+ type GFromExprs t = t Result
114171
115172 default gfromColumns :: forall context.
116− ( Generic (Record (t (Reify context)))
117− , G.GTable (TTable (Reify context)) TColumns (Col (Reify context)) (GRep t (Reify context))
118− , G.GColumns TColumns (GRep t (Reify context)) ~ GColumns t
173+ ( SRel8able t Aggregate
174+ , SRel8able t Expr
175+ , forall table. SRel8able t (Field table)
176+ , SRel8able t Name
177+ , SSerialize t
119178 )
120− => GColumns t (Col (Reify context)) -> t (Reify context)
121− gfromColumns =
122− unrecord .
123− to .
124− G.gfromColumns @(TTable (Reify context)) @TColumns fromColumns
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
125186
126187 default gtoColumns :: forall context.
127− ( Generic (Record (t (Reify context)))
128− , G.GTable (TTable (Reify context)) TColumns (Col (Reify context)) (GRep t (Reify context))
129− , G.GColumns TColumns (GRep t (Reify context)) ~ GColumns t
130− )
131− => t (Reify context) -> GColumns t (Col (Reify context))
132− gtoColumns =
133− G.gtoColumns @(TTable (Reify context)) @TColumns toColumns .
134− from .
135− Record
136−
137− default greify :: forall context.
138− ( Generic (Record (t context))
139− , Generic (Record (t (Reify context)))
140− , GMappable (TTable (Reify context)) (GRep t (Reify context))
141− , GRep t context ~ GMap TUnreify (GRep t (Reify context))
188+ ( SRel8able t Aggregate
189+ , SRel8able t Expr
190+ , forall table. SRel8able t (Field table)
191+ , SRel8able t Name
192+ , SSerialize t
142193 )
143− => t context -> t (Reify context)
144− greify =
145− unrecord .
146− to .
147− gunmap @(TTable (Reify context)) (Proxy @TUnreify) (reify Refl) .
148− from .
149− Record
150−
151− default gunreify :: forall context.
152− ( Generic (Record (t context))
153− , Generic (Record (t (Reify context)))
154− , GMappable (TTable (Reify context)) (GRep t (Reify context))
155− , GRep t context ~ GMap TUnreify (GRep t (Reify context))
156− )
157− => t (Reify context) -> t context
158− gunreify =
159− unrecord .
160− to .
161− gmap @(TTable (Reify context)) (Proxy @TUnreify) (unreify Refl) .
162− from .
163− Record
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
164209
165210
166211type Algebra :: K.Rel8able -> K.Algebra
167−type Algebra t = GAlgebra (GRep t (Reify Result))
212+type Algebra t = GAlgebra (GRep t Expr)
168213
169214
170215type GRep :: K.Rel8able -> K.Context -> Type -> Type
171216type GRep t context = Rep (Record (t context))
172217
173218
174−data TUnreifyContext :: Type -> Exp K.Context
175−type instance Eval (TUnreifyContext a) = UnwrapReify (Eval (TContext a))
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+24−109
@@ -12,8 +12,7 @@
1212{-# language UndecidableInstances #-}
1313
1414module Rel8.Generic.Table
15− ( GGTable, GGColumns, GGContext, ggfromColumns, ggtoColumns, ggtable
16− , GGToExprs, ggfromResult, ggtoResult
15+ ( GGSerialize, GGColumns, ggfromResult, ggtoResult
1716 , GAlgebra
1817 )
1918where
@@ -26,43 +25,19 @@ import Prelude ()
2625-- rel8
2726import Rel8.FCF ( Eval, Exp )
2827import Rel8.Generic.Table.ADT
29− ( GTableADT, GColumnsADT, gfromColumnsADT, gtoColumnsADT, gtableADT
30− , GToExprsADT, gtoResultADT, gfromResultADT
31− )
32−import Rel8.Generic.Table.Record
33− ( GTable, GColumns, GContext, gfromColumns, gtoColumns, gtable
34− , GToExprs, gtoResult, gfromResult
28+ ( GSerializeADT, GColumnsADT, gtoResultADT, gfromResultADT
3529 )
30+import Rel8.Generic.Table.Record ( GSerialize, GColumns, gtoResult, gfromResult )
3631import Rel8.Kind.Algebra
3732 ( Algebra( Product, Sum )
3833 , SAlgebra( SProduct, SSum )
3934 , KnownAlgebra, algebraSing
4035 )
41−import Rel8.Schema.Context ( Col )
4236import qualified Rel8.Schema.Kind as K
43−import Rel8.Schema.Null ( Nullify )
44−import Rel8.Schema.Spec ( Spec( Spec ), SSpec )
4537import Rel8.Schema.Result ( Result )
4638
4739
48−data GGTable
49− :: Algebra
50− -> (Type -> Exp Constraint)
51− -> (Type -> Exp K.HTable)
52− -> K.HContext
53− -> (Type -> Type)
54− -> Exp Constraint
55−
56−
57−type instance Eval (GGTable 'Product _Table _Columns context rep) =
58− GTable _Table _Columns context rep
59−
60−
61−type instance Eval (GGTable 'Sum _Table _Columns context rep) =
62− GTableADT _Table _Columns context rep
63−
64−
65−data GGToExprs
40+data GGSerialize
6641 :: Algebra
6742 -> (Type -> Type -> Exp Constraint)
6843 -> (Type -> Exp K.HTable)
@@ -71,12 +46,12 @@ data GGToExprs
7146 -> Exp Constraint
7247
7348
74−type instance Eval (GGToExprs 'Product _ToExprs _Columns exprs rep) =
75− GToExprs _ToExprs _Columns exprs rep
49+type instance Eval (GGSerialize 'Product _Serialize _Columns exprs rep) =
50+ GSerialize _Serialize _Columns exprs rep
7651
7752
78−type instance Eval (GGToExprs 'Sum _ToExprs _Columns exprs rep) =
79− GToExprsADT _ToExprs _Columns exprs rep
53+type instance Eval (GGSerialize 'Sum _Serialize _Columns exprs rep) =
54+ GSerializeADT _Serialize _Columns exprs rep
8055
8156
8257data GGColumns
@@ -92,19 +67,6 @@ type instance Eval (GGColumns 'Product _Columns rep) = GColumns _Columns rep
9267type instance Eval (GGColumns 'Sum _Columns rep) = GColumnsADT _Columns rep
9368
9469
95−data GGContext
96− :: Algebra
97− -> (Type -> Exp K.Context)
98− -> (Type -> Type)
99− -> Exp K.Context
100−
101−
102−type instance Eval (GGContext 'Product _Context rep) = GContext _Context rep
103−
104−
105−type instance Eval (GGContext 'Sum _Context _rep) = Result
106−
107−
10870type GAlgebra :: (Type -> Type) -> Algebra
10971type family GAlgebra rep where
11072 GAlgebra (M1 _ _ rep) = GAlgebra rep
@@ -115,74 +77,27 @@ type family GAlgebra rep where
11577 GAlgebra (K1 _ _) = 'Product
11678
11779
118−ggfromColumns :: forall algebra _Table _Columns rep context x.
119− ( KnownAlgebra algebra
120− , Eval (GGTable algebra _Table _Columns context rep)
121− )
122− => (forall spec. algebra ~ 'Sum => context spec -> Col Result spec)
123− -> (forall spec. algebra ~ 'Sum => Col Result spec -> context spec)
124− -> (forall a. Eval (_Table a) => Eval (_Columns a) context -> a)
125− -> Eval (GGColumns algebra _Columns rep) context
126− -> rep x
127−ggfromColumns = case algebraSing @algebra of
128− SProduct -> \_ _ -> gfromColumns @_Table @_Columns
129− SSum -> gfromColumnsADT @_Table @_Columns
130−
131−
132−ggtoColumns :: forall algebra _Table _Columns rep context x.
133− ( KnownAlgebra algebra
134− , Eval (GGTable algebra _Table _Columns context rep)
135− )
136− => (forall spec. algebra ~ 'Sum => context spec -> Col Result spec)
137− -> (forall spec. algebra ~ 'Sum => Col Result spec -> context spec)
138− -> (forall a. Eval (_Table a) => a -> Eval (_Columns a) context)
139− -> rep x
140− -> Eval (GGColumns algebra _Columns rep) context
141−ggtoColumns = case algebraSing @algebra of
142− SProduct -> \_ _ -> gtoColumns @_Table @_Columns
143− SSum -> gtoColumnsADT @_Table @_Columns
144−
145−
146−ggtable :: forall algebra _Table _Columns rep context.
147− ( KnownAlgebra algebra
148− , Eval (GGTable algebra _Table _Columns context rep)
149− )
150− => (forall a proxy. Eval (_Table a) => proxy a -> Eval (_Columns a) context)
151− -> (forall a labels. ()
152− => SSpec ('Spec labels a)
153− -> context ('Spec labels a)
154− -> context ('Spec labels (Nullify a)))
155− -> Eval (GGColumns algebra _Columns rep) context
156−ggtable = case algebraSing @algebra of
157− SProduct -> \table _ -> gtable @_Table @_Columns @_ @rep table
158− SSum -> gtableADT @_Table @_Columns @_ @rep
159−
160−
161−ggfromResult :: forall algebra _ToExprs _Columns exprs rep x.
80+ggfromResult :: forall algebra _Serialize _Columns exprs rep x.
16281 ( KnownAlgebra algebra
163− , Eval (GGToExprs algebra _ToExprs _Columns exprs rep)
82+ , Eval (GGSerialize algebra _Serialize _Columns exprs rep)
16483 )
165− => (forall expr a proxy. Eval (_ToExprs expr a)
166− => proxy expr
167− -> Eval (_Columns expr) (Col Result)
168− -> a)
169− -> Eval (GGColumns algebra _Columns exprs) (Col Result)
84+ => (forall expr a proxy. Eval (_Serialize expr a)
85+ => proxy expr -> Eval (_Columns expr) Result -> a)
86+ -> Eval (GGColumns algebra _Columns exprs) Result
17087 -> rep x
171−ggfromResult = case algebraSing @algebra of
172− SProduct -> gfromResult @_ToExprs @_Columns @exprs
173− SSum -> gfromResultADT @_ToExprs @_Columns @exprs
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
17491
17592
176−ggtoResult :: forall algebra _ToExprs _Columns exprs rep x.
93+ggtoResult :: forall algebra _Serialize _Columns exprs rep x.
17794 ( KnownAlgebra algebra
178− , Eval (GGToExprs algebra _ToExprs _Columns exprs rep)
95+ , Eval (GGSerialize algebra _Serialize _Columns exprs rep)
17996 )
180− => (forall expr a proxy. Eval (_ToExprs expr a)
181− => proxy expr
182− -> a
183− -> Eval (_Columns expr) (Col Result))
97+ => (forall expr a proxy. Eval (_Serialize expr a)
98+ => proxy expr -> a -> Eval (_Columns expr) Result)
18499 -> rep x
185− -> Eval (GGColumns algebra _Columns exprs) (Col Result)
186−ggtoResult = case algebraSing @algebra of
187− SProduct -> gtoResult @_ToExprs @_Columns @exprs
188− SSum -> gtoResultADT @_ToExprs @_Columns @exprs
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.hs+61−203
@@ -4,7 +4,6 @@
44{-# language FlexibleInstances #-}
55{-# language LambdaCase #-}
66{-# language MultiParamTypeClasses #-}
7−{-# language PolyKinds #-}
87{-# language RankNTypes #-}
98{-# language ScopedTypeVariables #-}
109{-# language StandaloneKindSignatures #-}
@@ -14,13 +13,13 @@
1413{-# language UndecidableInstances #-}
1514
1615module Rel8.Generic.Table.ADT
17− ( GTableADT, GColumnsADT, gfromColumnsADT, gtoColumnsADT, gtableADT
18− , GTableADT', GColumnsADT'
19− , GToExprsADT, gfromResultADT, gtoResultADT
16+ ( GSerializeADT, GColumnsADT, gfromResultADT, gtoResultADT
17+ , GSerializeADT', GColumnsADT'
2018 )
2119where
2220
2321-- base
22+import Data.Functor.Identity ( Identity( Identity ) )
2423import Data.Kind ( Constraint, Type )
2524import Data.Proxy ( Proxy( Proxy ) )
2625import GHC.Generics
@@ -33,23 +32,14 @@ import Prelude hiding ( null )
3332
3433-- rel8
3534import Rel8.FCF ( Eval, Exp )
36−import Rel8.Generic.Table.Record
37− ( GTable, GColumns, gtable
38− , GToExprs, gfromResult, gtoResult
39− )
40−import Rel8.Schema.Context.Label ( HLabelable, hlabeler, labeler, unlabeler )
41−import Rel8.Schema.HTable ( HTable, hmap )
42−import Rel8.Schema.HTable.Identity ( HIdentity( HType ), HType )
35+import Rel8.Generic.Table.Record ( GSerialize, GColumns, gfromResult, gtoResult )
36+import Rel8.Schema.HTable ( HTable )
37+import Rel8.Schema.HTable.Identity ( HIdentity( HIdentity ) )
4338import Rel8.Schema.HTable.Label ( HLabel, hlabel, hunlabel )
4439import Rel8.Schema.HTable.Nullify ( HNullify, hnulls, hnullify, hunnullify )
4540import Rel8.Schema.HTable.Product ( HProduct( HProduct ) )
4641import qualified Rel8.Schema.Kind as K
47−import Rel8.Schema.Null ( Nullify )
48−import Rel8.Schema.Spec ( Spec( Spec ), SSpec )
49−import Rel8.Schema.Result
50− ( Col( R ), Result
51− , null, nullifier, unnullifier
52− )
42+import Rel8.Schema.Result ( Result, null, nullifier, unnullifier )
5343import Rel8.Type.Tag ( Tag( Tag ) )
5444
5545-- text
@@ -61,7 +51,7 @@ type GColumnsADT
6151 -> (Type -> Type) -> K.HTable
6252type family GColumnsADT _Columns rep where
6353 GColumnsADT _Columns (M1 D _ rep) =
64− GColumnsADT' _Columns (HLabel "tag" (HType Tag)) rep
54+ GColumnsADT' _Columns (HLabel "tag" (HIdentity Tag)) rep
6555
6656
6757type GColumnsADT'
@@ -75,246 +65,118 @@ type family GColumnsADT' _Columns htable rep where
7565 HProduct htable (HLabel label (HNullify (GColumns _Columns rep)))
7666
7767
78−type GTableADT
79− :: (Type -> Exp Constraint)
80− -> (Type -> Exp K.HTable)
81− -> K.HContext -> (Type -> Type) -> Constraint
82−class GTableADT _Table _Columns context rep where
83− gfromColumnsADT :: ()
84− => (forall spec. context spec -> Col Result spec)
85− -> (forall spec. Col Result spec -> context spec)
86− -> (forall a. Eval (_Table a) => Eval (_Columns a) context -> a)
87− -> GColumnsADT _Columns rep context
88− -> rep x
89−
90− gtoColumnsADT :: ()
91− => (forall spec. context spec -> Col Result spec)
92− -> (forall spec. Col Result spec -> context spec)
93− -> (forall a. Eval (_Table a) => a -> Eval (_Columns a) context)
94− -> rep x
95− -> GColumnsADT _Columns rep context
96−
97− gtableADT :: ()
98− => (forall a proxy. Eval (_Table a) => proxy a -> Eval (_Columns a) context)
99− -> (forall a labels. ()
100− => SSpec ('Spec labels a)
101− -> context ('Spec labels a)
102− -> context ('Spec labels (Nullify a)))
103− -> GColumnsADT _Columns rep context
104−
105−
106−instance
107− ( htable ~ HLabel "tag" (HType Tag)
108− , HTable (GColumnsADT _Columns (M1 D meta rep))
109− , Eval (_Table (htable context))
110− , Eval (_Columns (htable context)) ~ htable
111− , GTableADT' _Table _Columns htable context rep
112− , GToExprsADT' (Const _Table) _Columns htable rep rep
113− )
114− => GTableADT _Table _Columns context (M1 D meta rep)
115− where
116− gfromColumnsADT fromContext toContext fromColumns =
117− gfromResultADT @(Const _Table) @_Columns @(M1 D meta rep) @(M1 D meta rep)
118− (const (fromColumns . hmap toContext)) .
119− hmap fromContext
120−
121− gtoColumnsADT fromContext toContext toColumns =
122− hmap toContext .
123− gtoResultADT @(Const _Table) @_Columns @(M1 D meta rep) @(M1 D meta rep)
124− (const (hmap fromContext . toColumns))
125−
126− gtableADT table hnullifier =
127− gtableADT' @_Table @_Columns @htable @context @rep table hnullifier htable
128− where
129− htable = table (Proxy @(htable context))
130−
131−
132−type GTableADT'
133− :: (Type -> Exp Constraint)
134− -> (Type -> Exp K.HTable)
135− -> K.HTable -> K.HContext -> (Type -> Type) -> Constraint
136−class GTableADT' _Table _Columns htable context rep where
137− gtableADT' :: ()
138− => (forall a proxy. Eval (_Table a) => proxy a -> Eval (_Columns a) context)
139− -> (forall a labels. ()
140− => SSpec ('Spec labels a)
141− -> context ('Spec labels a)
142− -> context ('Spec labels (Nullify a)))
143− -> htable context
144− -> GColumnsADT' _Columns htable rep context
145−
146−
147−instance
148− ( htable' ~ GColumnsADT' _Columns htable a
149− , GTableADT' _Table _Columns htable context a
150− , GTableADT' _Table _Columns htable' context b
151− )
152− => GTableADT' _Table _Columns htable context (a :+: b)
153− where
154− gtableADT' table hnullifier =
155− gtableADT' @_Table @_Columns @_ @_ @b table hnullifier .
156− gtableADT' @_Table @_Columns @_ @_ @a table hnullifier
157−
158−
159−instance meta ~ 'MetaCons label _fixity _isRecord =>
160− GTableADT' _Table _Columns htable context (M1 C meta U1)
161− where
162− gtableADT' _ _ = id
163−
164−
165−instance {-# OVERLAPPABLE #-}
166− ( HTable (GColumns _Columns rep)
167− , GTable _Table _Columns context rep
168− , HLabelable context
169− , meta ~ 'MetaCons label _fixity _isRecord
170− , KnownSymbol label
171− , GColumnsADT' _Columns htable (M1 C ('MetaCons label _fixity _isRecord) rep) ~
172− HProduct htable (HLabel label (HNullify (GColumns _Columns rep)))
173− )
174− => GTableADT' _Table _Columns htable context (M1 C meta rep)
175− where
176− gtableADT' table hnullifier htable =
177− HProduct htable $
178− hlabel hlabeler $
179− hnullify hnullifier $
180− gtable @_Table @_Columns @_ @rep table
181−
182−
183−type GToExprsADT
68+type GSerializeADT
18469 :: (Type -> Type -> Exp Constraint)
18570 -> (Type -> Exp K.HTable)
18671 -> (Type -> Type) -> (Type -> Type) -> Constraint
187−class GToExprsADT _ToExprs _Columns exprs rep where
72+class GSerializeADT _Serialize _Columns exprs rep where
18873 gfromResultADT :: ()
189− => (forall expr a proxy.
190− ( Eval (_ToExprs expr a)
191− , HTable (Eval (_Columns expr))
192− )
193− => proxy expr
194− -> Eval (_Columns expr) (Col Result)
195− -> a)
196− -> GColumnsADT _Columns exprs (Col Result)
74+ => (forall expr a proxy. Eval (_Serialize expr a)
75+ => proxy expr -> Eval (_Columns expr) Result -> a)
76+ -> GColumnsADT _Columns exprs Result
19777 -> rep x
19878
19979 gtoResultADT :: ()
200− => (forall expr a proxy.
201− ( Eval (_ToExprs expr a)
202− , HTable (Eval (_Columns expr))
203− )
204− => proxy expr
205− -> a
206− -> Eval (_Columns expr) (Col Result))
80+ => (forall expr a proxy. Eval (_Serialize expr a)
81+ => proxy expr -> a -> Eval (_Columns expr) Result)
20782 -> rep x
208− -> GColumnsADT _Columns exprs (Col Result)
83+ -> GColumnsADT _Columns exprs Result
20984
21085
21186instance
212− ( htable ~ HLabel "tag" (HType Tag)
213− , GToExprsADT' _ToExprs _Columns htable exprs rep
87+ ( htable ~ HLabel "tag" (HIdentity Tag)
88+ , GSerializeADT' _Serialize _Columns htable exprs rep
21489 )
215− => GToExprsADT _ToExprs _Columns (M1 D meta exprs) (M1 D meta rep)
90+ => GSerializeADT _Serialize _Columns (M1 D meta exprs) (M1 D meta rep)
21691 where
21792 gfromResultADT fromResult columns =
218− case gfromResultADT' @_ToExprs @_Columns @_ @exprs fromResult tag columns of
93+ case gfromResultADT' @_Serialize @_Columns @htable @exprs @rep fromResult tag columns of
21994 Just rep -> M1 rep
22095 _ -> error "ADT.fromColumns: mismatch between tag and data"
22196 where
222− tag = (\(HType (R a)) -> a) . hunlabel @_ @"tag" unlabeler
97+ tag = (\(HIdentity (Identity a)) -> a) . hunlabel @"tag"
22398
22499 gtoResultADT toResult (M1 rep) =
225− gtoResultADT' @_ToExprs @_Columns @_ @exprs toResult tag (Just rep)
100+ gtoResultADT' @_Serialize @_Columns @htable @exprs @rep toResult tag (Just rep)
226101 where
227− tag = hlabel @_ @"tag" labeler . HType . R
102+ tag = hlabel @"tag" . HIdentity . Identity
228103
229104
230−type GToExprsADT'
105+type GSerializeADT'
231106 :: (Type -> Type -> Exp Constraint)
232107 -> (Type -> Exp K.HTable)
233108 -> K.HTable -> (Type -> Type) -> (Type -> Type) -> Constraint
234−class GToExprsADT' _ToExprs _Columns htable exprs rep where
235− gfromResultADT' :: ()
236− => (forall expr a proxy.
237− ( Eval (_ToExprs expr a)
238− , HTable (Eval (_Columns expr))
239− )
240− => proxy expr
241− -> Eval (_Columns expr) (Col Result)
242− -> a)
243− -> (htable (Col Result) -> Tag)
244− -> GColumnsADT' _Columns htable exprs (Col Result)
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
245115 -> Maybe (rep x)
246116
247− gtoResultADT' :: ()
248− => (forall expr a proxy.
249− ( Eval (_ToExprs expr a)
250− , HTable (Eval (_Columns expr))
251− )
252− => proxy expr
253− -> a
254− -> Eval (_Columns expr) (Col Result))
255− -> (Tag -> htable (Col Result))
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)
256121 -> Maybe (rep x)
257− -> GColumnsADT' _Columns htable exprs (Col Result)
122+ -> GColumnsADT' _Columns htable exprs context
258123
259124 extract :: GColumnsADT' _Columns htable exprs context -> htable context
260125
261126
262127instance
263− ( htable' ~ GColumnsADT' _Columns htable a
264− , GToExprsADT' _ToExprs _Columns htable a rep1
265− , GToExprsADT' _ToExprs _Columns htable' b rep2
128+ ( htable' ~ GColumnsADT' _Columns htable exprs1
129+ , GSerializeADT' _Serialize _Columns htable exprs1 a
130+ , GSerializeADT' _Serialize _Columns htable' exprs2 b
266131 )
267− => GToExprsADT' _ToExprs _Columns htable (a :+: b) (rep1 :+: rep2)
132+ => GSerializeADT' _Serialize _Columns htable (exprs1 :+: exprs2) (a :+: b)
268133 where
269134 gfromResultADT' fromResult f columns =
270135 case ma of
271136 Just a -> Just (L1 a)
272137 Nothing -> R1 <$>
273− gfromResultADT' @_ToExprs @_Columns @_ @b @rep2
138+ gfromResultADT' @_Serialize @_Columns @_ @exprs2 @b
274139 fromResult
275− (f . extract @_ToExprs @_Columns @_ @a @rep1)
140+ (f . extract @_Serialize @_Columns @_ @exprs1 @a)
276141 columns
277142 where
278143 ma =
279− gfromResultADT' @_ToExprs @_Columns @_ @a @rep1
144+ gfromResultADT' @_Serialize @_Columns @_ @exprs1 @a
280145 fromResult
281146 f
282− (extract @_ToExprs @_Columns @_ @b @rep2 columns)
147+ (extract @_Serialize @_Columns @_ @exprs2 @b columns)
283148
284149 gtoResultADT' toResult tag = \case
285150 Just (L1 a) ->
286− gtoResultADT' @_ToExprs @_Columns @_ @b @rep2
151+ gtoResultADT' @_Serialize @_Columns @_ @exprs2 @b
287152 toResult
288− (\_ -> gtoResultADT' @_ToExprs @_Columns @_ @a @rep1
153+ (\_ -> gtoResultADT' @_Serialize @_Columns @_ @exprs1 @a
289154 toResult
290155 tag
291156 (Just a))
292157 Nothing
293158 Just (R1 b) ->
294− gtoResultADT' @_ToExprs @_Columns @_ @b @rep2
159+ gtoResultADT' @_Serialize @_Columns @_ @exprs2 @b
295160 toResult
296161 (\tag' ->
297− gtoResultADT' @_ToExprs @_Columns @_ @a @rep1
162+ gtoResultADT' @_Serialize @_Columns @_ @exprs1 @a
298163 toResult
299164 (\_ -> tag tag')
300165 Nothing)
301166 (Just b)
302167 Nothing ->
303− gtoResultADT' @_ToExprs @_Columns @_ @b @rep2
168+ gtoResultADT' @_Serialize @_Columns @_ @exprs2 @b
304169 toResult
305− (\_ -> gtoResultADT' @_ToExprs @_Columns @_ @a @rep1 toResult tag Nothing)
170+ (\_ -> gtoResultADT' @_Serialize @_Columns @_ @exprs1 @a toResult tag Nothing)
306171 Nothing
307172
308173 extract =
309− extract @_ToExprs @_Columns @_ @a @rep1 .
310− extract @_ToExprs @_Columns @_ @b @rep2
174+ extract @_Serialize @_Columns @_ @exprs1 @a .
175+ extract @_Serialize @_Columns @_ @exprs2 @b
311176
312177
313−instance
314− ( meta ~ 'MetaCons label _fixity _isRecord
315− , KnownSymbol label
316− )
317− => GToExprsADT' _ToExprs _Columns htable (M1 C meta U1) (M1 C meta U1)
178+instance (meta ~ 'MetaCons label _fixity _isRecord, KnownSymbol label) =>
179+ GSerializeADT' _Serialize _Columns _htable (M1 C meta U1) (M1 C meta U1)
318180 where
319181 gfromResultADT' _ tag columns
320182 | tag columns == tag' = Just (M1 U1)
@@ -331,33 +193,29 @@ instance
331193
332194instance {-# OVERLAPPABLE #-}
333195 ( HTable (GColumns _Columns exprs)
334− , GToExprs _ToExprs _Columns exprs rep
196+ , GSerialize _Serialize _Columns exprs rep
335197 , meta ~ 'MetaCons label _fixity _isRecord
336198 , KnownSymbol label
337− , GColumnsADT' _Columns htable (M1 C meta exprs) ~
199+ , GColumnsADT' _Columns htable (M1 C ('MetaCons label _fixity _isRecord) exprs) ~
338200 HProduct htable (HLabel label (HNullify (GColumns _Columns exprs)))
339201 )
340− => GToExprsADT' _ToExprs _Columns htable (M1 C meta exprs) (M1 C meta rep)
202+ => GSerializeADT' _Serialize _Columns htable (M1 C meta exprs) (M1 C meta rep)
341203 where
342204 gfromResultADT' fromResult tag (HProduct a b)
343205 | tag a == tag' =
344− M1 . gfromResult @_ToExprs @_Columns @exprs fromResult <$>
345− hunnullify unnullifier (hunlabel unlabeler b)
206+ M1 . gfromResult @_Serialize @_Columns @exprs @rep fromResult <$>
207+ hunnullify unnullifier (hunlabel b)
346208 | otherwise = Nothing
347209 where
348210 tag' = Tag $ pack $ symbolVal (Proxy @label)
349211
350212 gtoResultADT' toResult tag = \case
351− Nothing -> HProduct (tag tag') (hlabel labeler (hnulls (const null)))
213+ Nothing -> HProduct (tag tag') (hlabel (hnulls (const null)))
352214 Just (M1 rep) -> HProduct (tag tag') $
353− hlabel labeler $
215+ hlabel $
354216 hnullify nullifier $
355− gtoResult @_ToExprs @_Columns @exprs toResult rep
217+ gtoResult @_Serialize @_Columns @exprs @rep toResult rep
356218 where
357219 tag' = Tag $ pack $ symbolVal (Proxy @label)
358220
359221 extract (HProduct a _) = a
360−
361−
362−data Const :: (a -> Exp Constraint) -> a -> a -> Exp Constraint
363−type instance Eval (Const f x a) = (Eval (f a), x ~ a)
src/Rel8/Generic/Table/Record.hs+74−99
@@ -14,7 +14,7 @@
1414
1515module Rel8.Generic.Table.Record
1616 ( GTable, GColumns, GContext, gfromColumns, gtoColumns, gtable
17− , GToExprs, gfromResult, gtoResult
17+ , GSerialize, gfromResult, gtoResult
1818 )
1919where
2020
@@ -26,18 +26,13 @@ import GHC.Generics
2626 , C, D, S
2727 , Meta( MetaSel )
2828 )
29−import GHC.TypeLits ( KnownSymbol )
3029import Prelude hiding ( null )
3130
3231-- rel8
3332import Rel8.FCF ( Eval, Exp )
34−import Rel8.Schema.Context ( Col )
35−import Rel8.Schema.Context.Label ( HLabelable, hlabeler, hunlabeler )
36−import Rel8.Schema.HTable ( HTable )
3733import Rel8.Schema.HTable.Label ( HLabel, hlabel, hunlabel )
3834import Rel8.Schema.HTable.Product ( HProduct(..) )
3935import qualified Rel8.Schema.Kind as K
40−import Rel8.Schema.Result ( Result )
4136
4237
4338type GColumns :: (Type -> Exp K.HTable) -> (Type -> Type) -> K.HTable
@@ -60,8 +55,8 @@ type family GContext _Context rep where
6055type GTable
6156 :: (Type -> Exp Constraint)
6257 -> (Type -> Exp K.HTable)
63− -> K.HContext -> (Type -> Type) -> Constraint
64−class GTable _Table _Columns context rep
58+ -> (Type -> Type) -> Constraint
59+class GTable _Table _Columns rep
6560 where
6661 gfromColumns :: ()
6762 => (forall a. Eval (_Table a) => Eval (_Columns a) context -> a)
@@ -78,129 +73,109 @@ class GTable _Table _Columns context rep
7873 -> GColumns _Columns rep context
7974
8075
81−instance GTable _Table _Columns context rep =>
82− GTable _Table _Columns context (M1 D c rep)
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
8381 where
84− gfromColumns fromColumns =
85− M1 . gfromColumns @_Table @_Columns @context @rep fromColumns
86− gtoColumns toColumns (M1 a) =
87− gtoColumns @_Table @_Columns @context @rep toColumns a
88− gtable = gtable @_Table @_Columns @context @rep
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
8993
9094
91−instance GTable _Table _Columns context rep =>
92− GTable _Table _Columns context (M1 C c rep)
95+instance GTable _Table _Columns rep => GTable _Table _Columns (M1 D c rep)
9396 where
9497 gfromColumns fromColumns =
95− M1 . gfromColumns @_Table @_Columns @context @rep fromColumns
98+ M1 . gfromColumns @_Table @_Columns @rep fromColumns
9699 gtoColumns toColumns (M1 a) =
97− gtoColumns @_Table @_Columns @context @rep toColumns a
98− gtable = gtable @_Table @_Columns @context @rep
100+ gtoColumns @_Table @_Columns @rep toColumns a
101+ gtable = gtable @_Table @_Columns @rep
99102
100103
101−instance
102− ( GTable _Table _Columns context rep1
103− , GTable _Table _Columns context rep2
104− )
105− => GTable _Table _Columns context (rep1 :*: rep2)
104+instance GSerialize _Serialize _Columns exprs rep =>
105+ GSerialize _Serialize _Columns (M1 D c exprs) (M1 D c rep)
106106 where
107− gfromColumns fromColumns (HProduct a b) =
108− gfromColumns @_Table @_Columns @context @rep1 fromColumns a :*:
109− gfromColumns @_Table @_Columns @context @rep2 fromColumns b
110− gtoColumns toColumns (a :*: b) = HProduct
111− (gtoColumns @_Table @_Columns @context @rep1 toColumns a)
112− (gtoColumns @_Table @_Columns @context @rep2 toColumns b)
113− gtable table = HProduct
114− (gtable @_Table @_Columns @context @rep1 table)
115− (gtable @_Table @_Columns @context @rep2 table)
107+ gfromResult fromResult =
108+ M1 . gfromResult @_Serialize @_Columns @exprs @rep fromResult
109+ gtoResult toResult (M1 a) =
110+ gtoResult @_Serialize @_Columns @exprs @rep toResult a
116111
117112
118−instance
119− ( HTable (Eval (_Columns a))
120− , Eval (_Table a)
121− , HLabelable context
122− , KnownSymbol label
123− , meta ~ 'MetaSel ('Just label) _su _ss _ds
124− , k1 ~ K1 i a
125− )
126− => GTable _Table _Columns context (M1 S meta k1)
113+instance GTable _Table _Columns rep => GTable _Table _Columns (M1 C c rep)
127114 where
128− gfromColumns fromColumns = M1 . K1 . fromColumns . hunlabel hunlabeler
129− gtoColumns toColumns (M1 (K1 a)) = hlabel hlabeler (toColumns a)
130− gtable table = hlabel hlabeler (table (Proxy @a))
131−
132−
133−type GToExprs
134− :: (Type -> Type -> Exp Constraint)
135− -> (Type -> Exp K.HTable)
136− -> (Type -> Type) -> (Type -> Type) -> Constraint
137−class GToExprs _ToExprs _Columns exprs rep where
138− gfromResult :: ()
139− => (forall expr a proxy.
140− ( Eval (_ToExprs expr a)
141− , HTable (Eval (_Columns expr))
142− )
143− => proxy expr
144− -> Eval (_Columns expr) (Col Result)
145− -> a)
146− -> GColumns _Columns exprs (Col Result)
147− -> rep x
148− gtoResult :: ()
149− => (forall expr a proxy.
150− ( Eval (_ToExprs expr a)
151− , HTable (Eval (_Columns expr))
152− )
153− => proxy expr
154− -> a
155− -> Eval (_Columns expr) (Col Result))
156− -> rep x
157− -> GColumns _Columns exprs (Col Result)
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
158120
159121
160−instance GToExprs _ToExprs _Columns exprs rep =>
161− GToExprs _ToExprs _Columns (M1 D c exprs) (M1 D c rep)
122+instance GSerialize _Serialize _Columns exprs rep =>
123+ GSerialize _Serialize _Columns (M1 C c exprs) (M1 C c rep)
162124 where
163125 gfromResult fromResult =
164− M1 . gfromResult @_ToExprs @_Columns @exprs fromResult
126+ M1 . gfromResult @_Serialize @_Columns @exprs @rep fromResult
165127 gtoResult toResult (M1 a) =
166− gtoResult @_ToExprs @_Columns @exprs toResult a
128+ gtoResult @_Serialize @_Columns @exprs @rep toResult a
167129
168130
169−instance GToExprs _ToExprs _Columns exprs rep =>
170− GToExprs _ToExprs _Columns (M1 C c exprs) (M1 C c rep)
131+instance (GTable _Table _Columns rep1, GTable _Table _Columns rep2) =>
132+ GTable _Table _Columns (rep1 :*: rep2)
171133 where
172− gfromResult fromResult =
173− M1 . gfromResult @_ToExprs @_Columns @exprs fromResult
174− gtoResult toResult (M1 a) =
175− gtoResult @_ToExprs @_Columns @exprs toResult a
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)
176143
177144
178145instance
179− ( GToExprs _ToExprs _Columns exprs1 rep1
180− , GToExprs _ToExprs _Columns exprs2 rep2
146+ ( GSerialize _Serialize _Columns expr1 rep1
147+ , GSerialize _Serialize _Columns expr2 rep2
181148 )
182− => GToExprs _ToExprs _Columns (exprs1 :*: exprs2) (rep1 :*: rep2)
149+ => GSerialize _Serialize _Columns (expr1 :*: expr2) (rep1 :*: rep2)
183150 where
184151 gfromResult fromResult (HProduct a b) =
185− gfromResult @_ToExprs @_Columns @exprs1 fromResult a :*:
186− gfromResult @_ToExprs @_Columns @exprs2 fromResult b
152+ gfromResult @_Serialize @_Columns @expr1 @rep1 fromResult a :*:
153+ gfromResult @_Serialize @_Columns @expr2 @rep2 fromResult b
187154 gtoResult toResult (a :*: b) =
188155 HProduct
189− (gtoResult @_ToExprs @_Columns @exprs1 toResult a)
190− (gtoResult @_ToExprs @_Columns @exprs2 toResult b)
156+ (gtoResult @_Serialize @_Columns @expr1 @rep1 toResult a)
157+ (gtoResult @_Serialize @_Columns @expr2 @rep2 toResult b)
191158
192159
193160instance
194− ( Eval (_ToExprs exprs a)
195− , HTable (Eval (_Columns exprs))
196− , KnownSymbol label
161+ ( Eval (_Table a)
197162 , meta ~ 'MetaSel ('Just label) _su _ss _ds
198− , k1 ~ K1 i exprs
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
199176 , k1' ~ K1 i a
200177 )
201− => GToExprs _ToExprs _Columns (M1 S meta k1) (M1 S meta k1')
178+ => GSerialize _Serialize _Columns (M1 S meta k1) (M1 S meta k1')
202179 where
203− gfromResult fromResult =
204− M1 . K1 . fromResult (Proxy @exprs) . hunlabel hunlabeler
205− gtoResult toResult (M1 (K1 a)) =
206− hlabel hlabeler (toResult (Proxy @exprs) a)
180+ gfromResult fromResult = M1 . K1 . fromResult (Proxy @expr) . hunlabel
181+ gtoResult toResult (M1 (K1 a)) = hlabel (toResult (Proxy @expr) a)
src/Rel8/Kind/Context.hs+8−33
@@ -1,13 +1,11 @@
11{-# language DataKinds #-}
22{-# language GADTs #-}
3−{-# language LambdaCase #-}
43{-# language StandaloneKindSignatures #-}
4+{-# language TypeSynonymInstances #-}
55
66module Rel8.Kind.Context
77 ( Reifiable( contextSing )
88 , SContext(..)
9− , sReifiable
10− , sLabelable
119 )
1210where
1311
@@ -18,12 +16,9 @@ import Prelude ()
1816-- rel8
1917import Rel8.Aggregate ( Aggregate )
2018import Rel8.Expr ( Expr )
21−import Rel8.Schema.Dict ( Dict( Dict ) )
22−import Rel8.Schema.Context ( Interpretation )
23−import Rel8.Schema.Context.Label ( Labelable )
19+import Rel8.Schema.Field ( Field )
2420import Rel8.Schema.Kind ( Context )
2521import Rel8.Schema.Name ( Name )
26−import Rel8.Schema.Reify ( Reify )
2722import Rel8.Schema.Result ( Result )
2823
2924
@@ -31,13 +26,13 @@ type SContext :: Context -> Type
3126data SContext context where
3227 SAggregate :: SContext Aggregate
3328 SExpr :: SContext Expr
29+ SField :: SContext (Field table)
3430 SName :: SContext Name
3531 SResult :: SContext Result
36− SReify :: SContext context -> SContext (Reify context)
3732
3833
3934type Reifiable :: Context -> Constraint
40−class Interpretation context => Reifiable context where
35+class Reifiable context where
4136 contextSing :: SContext context
4237
4338
@@ -49,33 +44,13 @@ instance Reifiable Expr where
4944 contextSing = SExpr
5045
5146
47+instance Reifiable (Field table) where
48+ contextSing = SField
49+
50+
5251instance Reifiable Result where
5352 contextSing = SResult
5453
5554
5655instance Reifiable Name where
5756 contextSing = SName
58−
59−
60−instance Reifiable context => Reifiable (Reify context) where
61− contextSing = SReify contextSing
62−
63−
64−sReifiable :: SContext context -> Dict Reifiable context
65−sReifiable = \case
66− SAggregate -> Dict
67− SExpr -> Dict
68− SName -> Dict
69− SResult -> Dict
70− SReify context -> case sReifiable context of
71− Dict -> Dict
72−
73−
74−sLabelable :: SContext context -> Dict Labelable context
75−sLabelable = \case
76− SAggregate -> Dict
77− SExpr -> Dict
78− SName -> Dict
79− SResult -> Dict
80− SReify context -> case sLabelable context of
81− Dict -> Dict
src/Rel8/Kind/Labels.hsdeleted−57
@@ -1,57 +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( SNil, SCons )
12− , KnownLabels( labelsSing )
13− , renderLabels
14− )
15−where
16−
17−-- base
18−import Data.Kind ( Constraint, Type )
19−import Data.List.NonEmpty ( NonEmpty, nonEmpty )
20−import Data.Maybe ( fromMaybe )
21−import Data.Proxy ( Proxy( Proxy ) )
22−import GHC.TypeLits ( KnownSymbol, Symbol, symbolVal )
23−import Prelude
24−
25−
26−type Labels :: Type
27−type Labels = [Symbol]
28−
29−
30−type SLabels :: Labels -> Type
31−data SLabels labels where
32− SNil :: SLabels '[]
33− SCons :: KnownSymbol label => Proxy label -> SLabels labels -> SLabels (label ': labels)
34−
35−
36−type KnownLabels :: Labels -> Constraint
37−class KnownLabels labels where
38− labelsSing :: SLabels labels
39−
40−
41−instance KnownLabels '[] where
42− labelsSing = SNil
43−
44−
45−instance (KnownSymbol label, KnownLabels labels) =>
46− KnownLabels (label ': labels)
47− where
48− labelsSing = SCons Proxy labelsSing
49−
50−
51−renderLabels :: SLabels labels -> NonEmpty String
52−renderLabels = fromMaybe (pure "anon") . nonEmpty . go
53− where
54− go :: SLabels labels -> [String]
55− go = \case
56− SNil -> []
57− SCons label labels -> symbolVal label : go labels
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+19
@@ -1,13 +1,17 @@
11{-# language FlexibleContexts #-}
22{-# language MonoLocalBinds #-}
3+{-# language ScopedTypeVariables #-}
4+{-# language TypeApplications #-}
35
46module Rel8.Query.Aggregate
57 ( aggregate
68 , countRows
9+ , mode
710 )
811where
912
1013-- base
14+import Data.Functor.Contravariant ( (>$<) )
1115import Data.Int ( Int64 )
1216import Prelude
1317
@@ -18,9 +22,16 @@ import qualified Opaleye.Aggregate as Opaleye
1822import Rel8.Aggregate ( Aggregates )
1923import Rel8.Expr ( Expr )
2024import Rel8.Expr.Aggregate ( countStar )
25+import Rel8.Expr.Order ( desc )
2126import Rel8.Query ( Query )
27+import Rel8.Query.Limit ( limit )
2228import Rel8.Query.Maybe ( optional )
2329import 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 )
2435import Rel8.Table.Opaleye ( aggregator )
2536import Rel8.Table.Maybe ( maybeTable )
2637
@@ -35,3 +46,11 @@ aggregate = mapOpaleye (Opaleye.aggregate aggregator)
3546-- will return @0@.
3647countRows :: Query a -> Query (Expr Int64)
3748countRows = 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+9−21
@@ -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
@@ -28,28 +27,17 @@ import Rel8.Table.Maybe ( MaybeTable( MaybeTable ), isJustTable )
2827
2928
3029-- | Filter 'EitherTable's, keeping only 'leftTable's.
31−keepLeftTable :: EitherTable a b -> Query a
30+keepLeftTable :: EitherTable Expr a b -> Query a
3231keepLeftTable e@(EitherTable _ a _) = do
3332 where_ $ isLeftTable e
34− pure a
33+ pure (extract a)
3534
3635
3736-- | Filter 'EitherTable's, keeping only 'rightTable's.
38−keepRightTable :: EitherTable a b -> Query b
37+keepRightTable :: EitherTable Expr a b -> Query b
3938keepRightTable e@(EitherTable _ _ b) = do
4039 where_ $ isRightTable e
41− pure b
42−
43−
44−-- | Extend an 'EitherTable' with a 'Query' if it's a 'rightTable'. If the
45−-- @EitherTable@ is a 'leftTable', the original value is preserved.
46−--
47−-- This is like the '>>=' implementation for @ExceptT@.
48−bindEitherTable :: (Table Expr a, Functor m)
49− => (i -> m (EitherTable a b)) -> EitherTable a i -> m (EitherTable a b)
50−bindEitherTable query e@(EitherTable input a i) = do
51− query i <&> \(EitherTable output a' b) ->
52− EitherTable (input <> output) (bool a a' (isRightTable e)) b
40+ pure (extract b)
5341
5442
5543-- | @bitraverseEitherTable f g x@ will pass all @leftTable@s through @f@ and
@@ -71,8 +59,8 @@ bindEitherTable query e@(EitherTable input a i) = do
7159bitraverseEitherTable :: ()
7260 => (a -> Query c)
7361 -> (b -> Query d)
74− -> EitherTable a b
75− -> Query (EitherTable c d)
62+ -> EitherTable Expr a b
63+ -> Query (EitherTable Expr c d)
7664bitraverseEitherTable f g e@(EitherTable tag _ _) = do
7765 mc@(MaybeTable _ c) <- optional (f =<< keepLeftTable e)
7866 md@(MaybeTable _ d) <- optional (g =<< keepRightTable e)
src/Rel8/Query/Evaluate.hs+28−61
@@ -1,82 +1,49 @@
1−{-# language DerivingStrategies #-}
21{-# language FlexibleContexts #-}
3−{-# language GeneralizedNewtypeDeriving #-}
4−{-# language NamedFieldPuns #-}
5−{-# language StandaloneKindSignatures #-}
2+{-# language TupleSections #-}
63
74module Rel8.Query.Evaluate
8− ( Evaluate
9− , eval
10− , evaluate
5+ ( evaluate
116 )
127where
138
149-- base
15−import Data.Kind ( Type )
16−import Data.Monoid ( Endo ( Endo ), appEndo )
17−import Prelude
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 )
1815
1916-- opaleye
2017import qualified Opaleye.Internal.HaskellDB.PrimQuery as Opaleye
21−import qualified Opaleye.Internal.PackMap as Opaleye
22−import qualified Opaleye.Internal.PrimQuery as Opaleye
23−import qualified Opaleye.Internal.QueryArr as Opaleye
24−import qualified Opaleye.Internal.Tag as Opaleye
25−import qualified Opaleye.Internal.Unpackspec as Opaleye
2618
2719-- rel8
2820import Rel8.Expr ( Expr )
21+import Rel8.Expr.Bool ( (&&.) )
22+import Rel8.Expr.Opaleye ( fromPrimExpr )
2923import Rel8.Query ( Query( Query ) )
24+import Rel8.Query.Rebind ( rebind )
3025import Rel8.Table ( Table )
31−import Rel8.Table.Opaleye ( unpackspec )
26+import Rel8.Table.Bool ( case_ )
27+import Rel8.Table.Undefined ( undefined )
3228
33−-- semigroupoids
34−import Data.Functor.Apply ( Apply )
35−import Data.Functor.Bind ( Bind, (>>-) )
3629
37−-- transformers
38−import Control.Monad.Trans.State.Strict ( State, get, put, runState )
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"
3935
4036
41−type Evaluations :: Type
42−data Evaluations = Evaluations
43− { tag :: !Opaleye.Tag
44− , bindings :: !(Endo (Opaleye.Bindings Opaleye.PrimExpr))
45− }
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
4646
4747
48−-- | Some PostgreSQL functions, such as 'Rel8.nextval', have side effects,
49−-- breaking the referential transparency we would otherwise enjoy.
50−--
51−-- To try to recover our ability to reason about such expressions, 'Rel8'
52−-- provides the 'Evaluate' monad, which allows us to control the evaluation
53−-- order of side-effects by sequencing them monadically.
54−type Evaluate :: Type -> Type
55−newtype Evaluate a = Evaluate (State Evaluations a)
56− deriving newtype (Functor, Apply, Applicative, Monad)
57−
58−
59−instance Bind Evaluate where
60− (>>-) = (>>=)
61−
62−
63−-- | 'eval' takes expressions that could potentially have side effects and
64−-- lifts them into the 'Evaluate' monad. The resulting expressions has no side
65−-- effetcs and can safely be reused.
66−eval :: Table Expr a => a -> Evaluate a
67−eval a = Evaluate $ do
68− Evaluations {tag, bindings} <- get
69− let
70− tag' = Opaleye.next tag
71− (a', bindings') = Opaleye.run $
72− Opaleye.runUnpackspec unpackspec (Opaleye.extractAttr "eval" tag') a
73− put Evaluations {tag = tag', bindings = bindings <> Endo (bindings' ++)}
74− pure a'
75−
76−
77−-- | 'evaluate' runs an 'Evaluate' inside the 'Query' monad.
78−evaluate :: Evaluate a -> Query a
79−evaluate (Evaluate m) = Query $ Opaleye.QueryArr $ \(_, query, tag) ->
80− case runState m (Evaluations tag mempty) of
81− (a, Evaluations {tag = tag', bindings}) ->
82− (a, Opaleye.Rebind True (appEndo bindings mempty) query, tag')
48+foldl1' :: (a -> a -> a) -> NonEmpty a -> a
49+foldl1' f (a :| as) = foldl' f a as
src/Rel8/Query/Exists.hs+14−16
@@ -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
@@ -11,46 +11,44 @@ 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.
@@ -60,7 +58,7 @@ withBy predicate bs = with $ \a -> bs >>= filter (predicate a)
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+19−15
@@ -19,16 +19,18 @@ import Prelude
1919import qualified Opaleye.Internal.HaskellDB.PrimQuery as Opaleye
2020
2121-- rel8
22−import Rel8.Expr ( Col( E, unE ), Expr )
22+import Rel8.Expr ( Expr )
2323import Rel8.Expr.Aggregate ( listAggExpr, nonEmptyAggExpr )
2424import Rel8.Expr.Opaleye ( mapPrimExpr )
2525import Rel8.Query ( Query )
2626import Rel8.Query.Aggregate ( aggregate )
2727import Rel8.Query.Maybe ( optional )
28+import Rel8.Query.Rebind ( rebind )
2829import Rel8.Schema.HTable.Vectorize ( hunvectorize )
2930import Rel8.Schema.Null ( Sql, Unnullify )
30−import Rel8.Schema.Spec ( SSpec( SSpec, info ) )
31−import Rel8.Table ( Table, fromColumns, toColumns )
31+import Rel8.Schema.Spec ( Spec( Spec, info ) )
32+import Rel8.Table ( Table, fromColumns )
33+import Rel8.Table.Cols ( toCols )
3234import Rel8.Table.Aggregate ( listAgg, nonEmptyAgg )
3335import Rel8.Table.List ( ListTable( ListTable ) )
3436import Rel8.Table.Maybe ( maybeTable )
@@ -45,12 +47,12 @@ import Rel8.Type.Information ( TypeInformation )
4547--
4648-- @many@ is analogous to 'Control.Applicative.many' from
4749-- @Control.Applicative@.
48−many :: Table Expr a => Query a -> Query (ListTable a)
50+many :: Table Expr a => Query a -> Query (ListTable Expr a)
4951many =
5052 fmap (maybeTable mempty (\(ListTable a) -> ListTable a)) .
5153 optional .
5254 aggregate .
53− fmap (listAgg . toColumns)
55+ fmap (listAgg . toCols)
5456
5557
5658-- | Aggregate a 'Query' into a 'NonEmptyTable'. If the supplied query returns
@@ -61,11 +63,11 @@ many =
6163--
6264-- @some@ is analogous to 'Control.Applicative.some' from
6365-- @Control.Applicative@.
64−some :: Table Expr a => Query a -> Query (NonEmptyTable a)
66+some :: Table Expr a => Query a -> Query (NonEmptyTable Expr a)
6567some =
6668 fmap (\(NonEmptyTable a) -> NonEmptyTable a) .
6769 aggregate .
68− fmap (nonEmptyAgg . toColumns)
70+ fmap (nonEmptyAgg . toCols)
6971
7072
7173-- | A version of 'many' specialised to single expressions.
@@ -82,18 +84,20 @@ someExpr = aggregate . fmap nonEmptyAggExpr
8284-- element of the given @ListTable@.
8385--
8486-- @catListTable@ is an inverse to 'many'.
85−catListTable :: Table Expr a => ListTable a -> Query a
86−catListTable (ListTable as) = pure $ fromColumns $ runIdentity $
87− hunvectorize (\SSpec {info} -> pure . E . sunnest info . unE) as
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
8891
8992
9093-- | Expand a 'NonEmptyTable' into a 'Query', where each row in the query is an
9194-- element of the given @NonEmptyTable@.
9295--
9396-- @catNonEmptyTable@ is an inverse to 'some'.
94−catNonEmptyTable :: Table Expr a => NonEmptyTable a -> Query a
95−catNonEmptyTable (NonEmptyTable as) = pure $ fromColumns $ runIdentity $
96− hunvectorize (\SSpec {info} -> pure . E . sunnest info . unE) as
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
97101
98102
99103-- | Expand an expression that contains a list into a 'Query', where each row
@@ -101,7 +105,7 @@ catNonEmptyTable (NonEmptyTable as) = pure $ fromColumns $ runIdentity $
101105--
102106-- @catList@ is an inverse to 'manyExpr'.
103107catList :: Sql DBType a => Expr [a] -> Query (Expr a)
104−catList = pure . sunnest typeInformation
108+catList = rebind "unnest" . sunnest typeInformation
105109
106110
107111-- | Expand an expression that contains a non-empty list into a 'Query', where
@@ -109,7 +113,7 @@ catList = pure . sunnest typeInformation
109113--
110114-- @catNonEmpty@ is an inverse to 'someExpr'.
111115catNonEmpty :: Sql DBType a => Expr (NonEmpty a) -> Query (Expr a)
112−catNonEmpty = pure . sunnest typeInformation
116+catNonEmpty = rebind "unnest" . sunnest typeInformation
113117
114118
115119sunnest :: TypeInformation (Unnullify a) -> Expr (list a) -> Expr a
src/Rel8/Query/Maybe.hs+24−44
@@ -1,32 +1,31 @@
1+{-# language GADTs #-}
2+{-# language LambdaCase #-}
3+{-# language NamedFieldPuns #-}
4+
15module Rel8.Query.Maybe
26 ( optional
37 , catMaybeTable
4− , bindMaybeTable
58 , traverseMaybeTable
69 )
710where
811
912-- base
10−import Data.Functor ( (<&>) )
1113import Prelude
1214
15+-- comonad
16+import Control.Comonad ( extract )
17+
1318-- opaleye
14−import qualified Opaleye.Internal.PackMap as Opaleye
15−import qualified Opaleye.Internal.PrimQuery as Opaleye
16−import qualified Opaleye.Internal.QueryArr as Opaleye
17−import qualified Opaleye.Internal.Tag as Opaleye
18−import qualified Opaleye.Internal.Unpackspec as Opaleye
19+import qualified Opaleye.Internal.MaybeFields as Opaleye
1920
2021-- rel8
21−import Rel8.Expr.Bool ( true )
22+import Rel8.Expr ( Expr )
2223import Rel8.Expr.Eq ( (==.) )
23−import Rel8.Expr.Opaleye ( toPrimExpr )
24+import Rel8.Expr.Opaleye ( fromColumn, fromPrimExpr )
2425import Rel8.Query ( Query )
2526import Rel8.Query.Filter ( where_ )
2627import Rel8.Query.Opaleye ( mapOpaleye )
27−import Rel8.Table.Maybe ( MaybeTable( MaybeTable ), isJustTable )
28−import Rel8.Table.Opaleye ( unpackspec )
29−import Rel8.Table.Tag ( Tag(..), fromExpr )
28+import Rel8.Table.Maybe ( MaybeTable(..), isJustTable )
3029
3130
3231-- | Convert a query that might return zero rows to a query that always returns
@@ -34,18 +33,11 @@ import Rel8.Table.Tag ( Tag(..), fromExpr )
3433--
3534-- To speak in more concrete terms, 'optional' is most useful to write @LEFT
3635-- JOIN@s.
37−optional :: Query a -> Query (MaybeTable a)
38−optional = mapOpaleye $ Opaleye.QueryArr . go
39− where
40− go query (i, left, tag) =
41− (MaybeTable (fromExpr t') a, join, Opaleye.next tag')
42− where
43− (MaybeTable Tag {expr = t} a, right, tag') =
44− Opaleye.runSimpleQueryArr (pure <$> query) (i, tag)
45− (t', bindings) = Opaleye.run $
46− Opaleye.runUnpackspec unpackspec (Opaleye.extractAttr "maybe" tag') t
47− join = Opaleye.Join Opaleye.LeftJoin condition [] bindings left right
48− 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+ }
4941
5042
5143-- | Filter out 'MaybeTable's, returning only the tables that are not-null.
@@ -53,36 +45,24 @@ optional = mapOpaleye $ Opaleye.QueryArr . go
5345-- This operation can be used to "undo" the effect of 'optional', which
5446-- operationally is like turning a @LEFT JOIN@ back into a full @JOIN@. You
5547-- can think of this as analogous to 'Data.Maybe.catMaybes'.
56−catMaybeTable :: MaybeTable a -> Query a
48+catMaybeTable :: MaybeTable Expr a -> Query a
5749catMaybeTable ma@(MaybeTable _ a) = do
5850 where_ $ isJustTable ma
59− pure a
60−
61−
62−-- | @bindMaybeTable f x@ is similar to the monadic bind (@>>=@) operation. It
63−-- allows you to "extend" an optional query with another query. If either the
64−-- input or output are 'Rel8.nothingTable', then the result is
65−-- 'Rel8.nothingTable'.
66−--
67−-- This is similar to 'traverseMaybeTable', followed by a @join@ on the
68−-- resulting @MaybeTable@s.
69−bindMaybeTable :: Functor m
70− => (a -> m (MaybeTable b)) -> MaybeTable a -> m (MaybeTable b)
71−bindMaybeTable query (MaybeTable input a) =
72− query a <&> \(MaybeTable output b) -> 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
8261-- the input is @nothingTable@, you will always get exactly one @nothingTable@
8362-- back.
84−traverseMaybeTable :: (a -> Query b) -> MaybeTable a -> Query (MaybeTable b)
63+traverseMaybeTable :: (a -> Query b) -> MaybeTable Expr a -> Query (MaybeTable Expr b)
8564traverseMaybeTable query ma@(MaybeTable input _) = do
86− MaybeTable output b <- optional (query =<< catMaybeTable ma)
87− where_ $ expr output ==. expr input
88− 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( E ) )
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 ( Name( Name ), Selects, Col( N ) )
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− N (Name name) -> case hfield exprs field of
72− E (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+52−46
@@ -1,4 +1,5 @@
11{-# language FlexibleContexts #-}
2+{-# language GADTs #-}
23
34module Rel8.Query.These
45 ( alignBy
@@ -7,36 +8,36 @@ module Rel8.Query.These
78 , keepThisTable, loseThisTable
89 , keepThatTable, loseThatTable
910 , keepThoseTable, loseThoseTable
10− , bindTheseTable
1111 , bitraverseTheseTable
1212 )
1313where
1414
1515-- base
16−import Data.Functor ( (<&>) )
1716import Prelude
1817
18+-- comonad
19+import Control.Comonad ( extract )
20+
1921-- opaleye
20−import qualified Opaleye.Internal.Join as Opaleye
22+import qualified Opaleye.Internal.PackMap as Opaleye
2123import qualified Opaleye.Internal.PrimQuery as Opaleye
24+import qualified Opaleye.Internal.QueryArr as Opaleye
25+import qualified Opaleye.Internal.Tag as Opaleye
2226
2327-- rel8
2428import Rel8.Expr ( Expr )
2529import Rel8.Expr.Bool ( boolExpr, not_ )
2630import Rel8.Expr.Eq ( (==.) )
27−import Rel8.Expr.Opaleye ( toColumn, toPrimExpr )
31+import Rel8.Expr.Opaleye ( toPrimExpr, traversePrimExpr )
2832import Rel8.Expr.Serialize ( litExpr )
2933import Rel8.Query ( Query )
3034import Rel8.Query.Filter ( where_ )
3135import Rel8.Query.Maybe ( optional )
3236import Rel8.Query.Opaleye ( zipOpaleyeWith )
33−import Rel8.Table ( Table )
3437import Rel8.Table.Either ( EitherTable( EitherTable ) )
3538import Rel8.Table.Maybe ( MaybeTable( MaybeTable ), isJustTable )
36−import Rel8.Table.Opaleye ( unpackspec )
37−import Rel8.Table.Tag ( Tag(..) )
3839import Rel8.Table.These
39− ( TheseTable( TheseTable )
40+ ( TheseTable( TheseTable, here, there )
4041 , hasHereTable, hasThereTable
4142 , isThisTable, isThatTable, isThoseTable
4243 )
@@ -44,86 +45,91 @@ import Rel8.Type.Tag ( EitherTag( IsLeft, IsRight ) )
4445
4546
4647-- | Corresponds to a @FULL OUTER JOIN@ between two queries.
47−alignBy :: (Table Expr a, Table Expr b)
48+alignBy :: ()
4849 => (a -> b -> Expr Bool)
49− -> Query a -> Query b -> Query (TheseTable a b)
50−alignBy condition as bs =
51− uncurry TheseTable <$> zipOpaleyeWith fullOuterJoin as bs
52− where
53− fullOuterJoin a b =
54− Opaleye.joinExplicit unpackspec unpackspec pure pure full a b on
55− where
56− full = Opaleye.FullJoin
57− on = toColumn . toPrimExpr . uncurry condition
58−
59−
60−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)
6175keepHereTable = loseThatTable
6276
6377
64−loseHereTable :: TheseTable a b -> Query b
78+loseHereTable :: TheseTable Expr a b -> Query b
6579loseHereTable = keepThatTable
6680
6781
68−keepThereTable :: TheseTable a b -> Query (MaybeTable a, b)
82+keepThereTable :: TheseTable Expr a b -> Query (MaybeTable Expr a, b)
6983keepThereTable = loseThisTable
7084
7185
72−loseThereTable :: TheseTable a b -> Query a
86+loseThereTable :: TheseTable Expr a b -> Query a
7387loseThereTable = keepThisTable
7488
7589
76−keepThisTable :: TheseTable a b -> Query a
90+keepThisTable :: TheseTable Expr a b -> Query a
7791keepThisTable t@(TheseTable (MaybeTable _ a) _) = do
7892 where_ $ isThisTable t
79− pure a
93+ pure (extract a)
8094
8195
82−loseThisTable :: TheseTable a b -> Query (MaybeTable a, b)
96+loseThisTable :: TheseTable Expr a b -> Query (MaybeTable Expr a, b)
8397loseThisTable t@(TheseTable ma (MaybeTable _ b)) = do
8498 where_ $ not_ $ isThisTable t
85− pure (ma, b)
99+ pure (ma, extract b)
86100
87101
88−keepThatTable :: TheseTable a b -> Query b
102+keepThatTable :: TheseTable Expr a b -> Query b
89103keepThatTable t@(TheseTable _ (MaybeTable _ b)) = do
90104 where_ $ isThatTable t
91− pure b
105+ pure (extract b)
92106
93107
94−loseThatTable :: TheseTable a b -> Query (a, MaybeTable b)
108+loseThatTable :: TheseTable Expr a b -> Query (a, MaybeTable Expr b)
95109loseThatTable t@(TheseTable (MaybeTable _ a) mb) = do
96110 where_ $ not_ $ isThatTable t
97− pure (a, mb)
111+ pure (extract a, mb)
98112
99113
100−keepThoseTable :: TheseTable a b -> Query (a, b)
114+keepThoseTable :: TheseTable Expr a b -> Query (a, b)
101115keepThoseTable t@(TheseTable (MaybeTable _ a) (MaybeTable _ b)) = do
102116 where_ $ isThoseTable t
103− pure (a, b)
117+ pure (extract a, extract b)
104118
105119
106−loseThoseTable :: TheseTable a b -> Query (EitherTable a b)
120+loseThoseTable :: TheseTable Expr a b -> Query (EitherTable Expr a b)
107121loseThoseTable t@(TheseTable (MaybeTable _ a) (MaybeTable _ b)) = do
108122 where_ $ not_ $ isThoseTable t
109− pure $ EitherTable result a b
123+ pure $ EitherTable tag a b
110124 where
111125 tag = boolExpr (litExpr IsLeft) (litExpr IsRight) (isThatTable t)
112− result = (mempty `asTypeOf` result) {expr = tag}
113−
114−
115−bindTheseTable :: (Table Expr a, Semigroup a, Functor m)
116− => (i -> m (TheseTable a b)) -> TheseTable a i -> m (TheseTable a b)
117−bindTheseTable query (TheseTable here (MaybeTable input i)) =
118− query i <&> \(TheseTable here' (MaybeTable output b)) ->
119− TheseTable (here <> here') (MaybeTable (input <> output) b)
120126
121127
122128bitraverseTheseTable :: ()
123129 => (a -> Query c)
124130 -> (b -> Query d)
125− -> TheseTable a b
126− -> Query (TheseTable c d)
131+ -> TheseTable Expr a b
132+ -> Query (TheseTable Expr c d)
127133bitraverseTheseTable f g t = do
128134 mc <- optional (f . fst =<< keepHereTable t)
129135 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/Context.hsdeleted−20
@@ -1,20 +0,0 @@
1−{-# language DataKinds #-}
2−{-# language StandaloneKindSignatures #-}
3−{-# language TypeFamilies #-}
4−
5−module Rel8.Schema.Context
6− ( Interpretation( Col )
7− )
8−where
9−
10−-- base
11−import Data.Kind ( Constraint )
12−import Prelude ()
13−
14−-- rel8
15−import Rel8.Schema.Kind ( Context, HContext )
16−
17−
18−type Interpretation :: Context -> Constraint
19−class Interpretation context where
20− data Col context :: HContext
src/Rel8/Schema/Context/Label.hsdeleted−62
@@ -1,62 +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 )
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 ( Col( R ), Result )
23−import Rel8.Schema.Spec.ConstrainDBType ( ConstrainDBType )
24−
25−
26−-- | The @Labelable@ class is an internal implementation detail of Rel8, and
27−-- indicates that we can successfully "name" all columns in a type.
28−type Labelable :: Context -> Constraint
29−class Interpretation context => Labelable context where
30− labeler :: ()
31− => Col context ('Spec labels a)
32− -> Col context ('Spec (label ': labels) a)
33−
34− unlabeler :: ()
35− => Col context ('Spec (label ': labels) a)
36− -> Col context ('Spec labels a)
37−
38−
39−instance Labelable Result where
40− labeler (R a) = R a
41− unlabeler (R a) = R a
42−
43−
44−type HLabelable :: HContext -> Constraint
45−class HLabelable context where
46− hlabeler :: ()
47− => context ('Spec labels a)
48− -> context ('Spec (label ': labels) a)
49−
50− hunlabeler :: ()
51− => context ('Spec (label ': labels) a)
52− -> context ('Spec labels a)
53−
54−
55−instance Labelable context => HLabelable (Col context) where
56− hlabeler = labeler
57− hunlabeler = unlabeler
58−
59−
60−instance HLabelable (Dict (ConstrainDBType constraint)) where
61− hlabeler Dict = Dict
62− hunlabeler Dict = Dict
src/Rel8/Schema/Context/Nullify.hs+105−149
@@ -1,188 +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( Aggregate ), Col( A )
29− , mapInputs
30− , unsafeMakeAggregate
31− )
32−import Rel8.Expr ( Expr, Col( E ) )
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.Schema.Context ( Interpretation )
31+import Rel8.Expr.Opaleye ( fromPrimExpr )
32+import Rel8.Kind.Context ( SContext(..) )
33+import Rel8.Schema.Field ( Field )
3734import qualified Rel8.Schema.Kind as K
38−import Rel8.Schema.Name ( Name( Name ), Col( N ) )
39−import Rel8.Schema.Null ( Nullify, Nullity( Null, NotNull ), Sql )
40−import Rel8.Schema.Dict ( Dict( Dict ) )
41−import Rel8.Schema.Spec ( Spec( Spec ), SSpec(..) )
42−import Rel8.Schema.Spec.ConstrainDBType ( ConstrainDBType )
43−import qualified Rel8.Schema.Spec.ConstrainDBType as ConstrainDBType
44−import Rel8.Table.Tag ( Tag(..), Taggable, fromAggregate, fromExpr, fromName )
45−
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(..) )
4639
47−type Nullifiable :: K.Context -> Constraint
48−class Interpretation context => Nullifiable context where
49− type ConstrainTag context :: Type -> Constraint
50− type ConstrainTag _context = DefaultConstrainTag
51−
52− encodeTag ::
53− ( Sql (ConstrainTag context) a
54− , KnownSymbol label
55− , Taggable a
56− )
57− => Tag label a
58− -> Col context ('Spec labels a)
59−
60− decodeTag ::
61− ( Sql (ConstrainTag context) a
62− , KnownSymbol label
63− , Taggable a
64− )
65− => Col context ('Spec labels a)
66− -> Tag label a
67−
68− nullifier :: ()
69− => Tag label a
70− -> (Expr a -> Expr Bool)
71− -> SSpec ('Spec labels x)
72− -> Col context ('Spec labels x)
73− -> Col context ('Spec labels (Nullify x))
74−
75− unnullifier :: ()
76− => SSpec ('Spec labels x)
77− -> Col context ('Spec labels (Nullify x))
78− -> Col context ('Spec labels x)
7940
41+type Nullifiability :: K.Context -> Type
42+data Nullifiability context where
43+ NAggregate :: Nullifiability Aggregate
44+ NExpr :: Nullifiability Expr
45+ NName :: Nullifiability Name
8046
81−instance Nullifiable Aggregate where
82− encodeTag Tag {aggregator, expr} =
83− A $ unsafeMakeAggregate toPrimExpr fromPrimExpr aggregator expr
8447
85− decodeTag (A aggregate) = fromAggregate aggregate
86−
87− nullifier Tag {expr} test SSpec {nullity} (A (Aggregate a)) =
88− A $
89− mapInputs (toPrimExpr . runTag nullity condition . fromPrimExpr) $
90− Aggregate $
91− runTag nullity condition <$> a
92− where
93− condition = test expr
48+type Nullifiable :: K.Context -> Constraint
49+class Nullifiable context where
50+ nullifiability :: Nullifiability context
9451
95− unnullifier SSpec {nullity} (A (Aggregate a)) =
96− A (Aggregate (unnull nullity <$> a))
9752
98− {-# INLINABLE encodeTag #-}
99− {-# INLINABLE decodeTag #-}
100− {-# INLINABLE nullifier #-}
101− {-# INLINABLE unnullifier #-}
53+instance Nullifiable Aggregate where
54+ nullifiability = NAggregate
10255
10356
10457instance Nullifiable Expr where
105− encodeTag Tag {expr} = E expr
106− decodeTag (E a) = fromExpr a
107− nullifier Tag {expr} test SSpec {nullity} (E a) =
108− E $ runTag nullity (test expr) a
109− unnullifier SSpec {nullity} (E a) = E $ unnull nullity a
110−
111− {-# INLINABLE encodeTag #-}
112− {-# INLINABLE decodeTag #-}
113− {-# INLINABLE nullifier #-}
114− {-# INLINABLE unnullifier #-}
58+ nullifiability = NExpr
11559
11660
11761instance Nullifiable Name where
118− encodeTag Tag {name} = N name
119− decodeTag (N name) = fromName name
120− nullifier _ _ _ (N (Name name)) = N (Name name)
121− unnullifier _ (N (Name name)) = N (Name name)
122−
123− {-# INLINABLE encodeTag #-}
124− {-# INLINABLE decodeTag #-}
125− {-# INLINABLE nullifier #-}
126− {-# INLINABLE unnullifier #-}
127−
128−
129−runTag :: Nullity a -> Expr Bool -> Expr a -> Expr (Nullify a)
130−runTag nullity tag a = case nullity of
131− Null -> boolExpr null a tag
132− 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
133131 where
134132 null = fromPrimExpr $ Opaleye.ConstExpr Opaleye.NullLit
135133
136134
137−unnull :: Nullity a -> Expr (Nullify a) -> Expr a
138−unnull nullity a = case nullity of
135+snullify :: Nullity a -> Expr a -> Expr (Nullify a)
136+snullify nullity a = case nullity of
139137 Null -> a
140− NotNull -> unsafeUnnullify a
141−
138+ NotNull -> nullify a
142139
143−type HNullifiable :: K.HContext -> Constraint
144−class HNullifiable context where
145− type HConstrainTag context :: Type -> Constraint
146− type HConstrainTag _context = DefaultConstrainTag
147140
148− hencodeTag :: (Sql (HConstrainTag context) a, KnownSymbol label, Taggable a)
149− => Tag label a
150− -> context ('Spec labels a)
151−
152− hdecodeTag :: (Sql (HConstrainTag context) a, KnownSymbol label, Taggable a)
153− => context ('Spec labels a)
154− -> Tag label a
155−
156− hnullifier :: ()
157− => Tag label a
158− -> (Expr a -> Expr Bool)
159− -> SSpec ('Spec labels x)
160− -> context ('Spec labels x)
161− -> context ('Spec labels (Nullify x))
162−
163− hunnullifier :: ()
164− => SSpec ('Spec labels x)
165− -> context ('Spec labels (Nullify x))
166− -> context ('Spec labels x)
167−
168−
169−instance Nullifiable context => HNullifiable (Col context) where
170− type HConstrainTag (Col context) = ConstrainTag context
171− hencodeTag = encodeTag
172− hdecodeTag = decodeTag
173− hnullifier = nullifier
174− hunnullifier = unnullifier
175−
176−
177−instance HNullifiable (Dict (ConstrainDBType constraint)) where
178− type HConstrainTag (Dict (ConstrainDBType constraint)) = constraint
179−
180− hencodeTag _ = Dict
181− hdecodeTag = mempty
182− hnullifier _ _ = ConstrainDBType.nullifier
183− hunnullifier = ConstrainDBType.unnullifier
184−
185−
186−type DefaultConstrainTag :: Type -> Constraint
187−class DefaultConstrainTag a
188−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.hsnew file+50
@@ -0,0 +1,50 @@
1+{-# language DataKinds #-}
2+{-# language FlexibleContexts #-}
3+{-# language MultiParamTypeClasses #-}
4+{-# language StandaloneKindSignatures #-}
5+{-# language TypeFamilies #-}
6+
7+module Rel8.Schema.Field
8+ ( Field(..)
9+ , fields
10+ )
11+where
12+
13+-- base
14+import Data.Functor.Identity ( Identity( Identity ) )
15+import Data.Kind ( Type )
16+import Prelude
17+
18+-- rel8
19+import Rel8.Schema.HTable ( HField, htabulate )
20+import Rel8.Schema.HTable.Identity ( HIdentity( HIdentity ) )
21+import Rel8.Schema.Kind as K
22+import Rel8.Schema.Null ( Sql )
23+import Rel8.Table
24+ ( Table, Columns, Context, fromColumns, toColumns
25+ , FromExprs, fromResult, toResult
26+ , Transpose
27+ )
28+import Rel8.Table.Transpose ( Transposes )
29+import Rel8.Type ( DBType )
30+
31+
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)
35+
36+
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
42+
43+ toColumns = HIdentity
44+ fromColumns (HIdentity a) = a
45+ toResult a = HIdentity (Identity a)
46+ fromResult (HIdentity (Identity a)) = a
47+
48+
49+fields :: Transposes context (Field table) table fields => fields
50+fields = fromColumns $ htabulate Field
src/Rel8/Schema/HTable.hs+51−24
@@ -16,11 +16,12 @@
1616module Rel8.Schema.HTable
1717 ( HTable (HField, HConstrainTable)
1818 , hfield, htabulate, htraverse, hdicts, hspecs
19− , hmap, 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 #-}
@@ -114,22 +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+
117128hmap :: HTable t
118− => (forall spec. context spec -> context' spec) -> t context -> t context'
129+ => (forall a. context a -> context' a) -> t context -> t context'
119130hmap f a = htabulate $ \field -> f (hfield a field)
120131
121132
122133htabulateA :: (HTable t, Apply m)
123− => (forall spec. HField t spec -> m (context spec)) -> m (t context)
134+ => (forall a. HField t a -> m (context a)) -> m (t context)
124135htabulateA f = htraverse getCompose $ htabulate $ Compose . f
125136{-# INLINABLE htabulateA #-}
126137
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)
127154
128−type GHField :: K.HTable -> Spec -> Type
129−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)
130157
131158
132−type GHTable :: K.HContext -> (Type -> Type) -> Constraint
159+type GHTable :: K.Context -> (Type -> Type) -> Constraint
133160class HTable (GHColumns rep) => GHTable context rep | rep -> context where
134161 type GHColumns rep :: K.HTable
135162 toGHColumns :: rep x -> GHColumns rep context
@@ -155,10 +182,10 @@ instance (GHTable context a, GHTable context b) => GHTable context (a :*: b) whe
155182
156183
157184-- | A HField type for indexing into HProduct.
158−type HProductField :: K.HTable -> K.HTable -> Spec -> Type
159−data HProductField x y spec
160− = HFst (HField x spec)
161− | 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)
162189
163190
164191instance (HTable x, HTable y) => HTable (HProduct x y) where
src/Rel8/Schema/HTable/Either.hs+2−3
@@ -15,17 +15,16 @@ import Prelude ()
1515
1616-- rel8
1717import Rel8.Schema.HTable ( HTable )
18−import Rel8.Schema.HTable.Identity ( HIdentity(..) )
18+import Rel8.Schema.HTable.Identity ( HIdentity )
1919import Rel8.Schema.HTable.Label ( HLabel )
2020import Rel8.Schema.HTable.Nullify ( HNullify )
2121import qualified Rel8.Schema.Kind as K
22−import Rel8.Schema.Spec ( Spec( Spec ) )
2322import Rel8.Type.Tag ( EitherTag )
2423
2524
2625type HEitherTable :: K.HTable -> K.HTable -> K.HTable
2726data HEitherTable left right context = HEitherTable
28− { htag :: HIdentity ('Spec '["isRight"] EitherTag) context
27+ { htag :: HLabel "isRight" (HIdentity EitherTag) context
2928 , hleft :: HLabel "Left" (HNullify left) context
3029 , hright :: HLabel "Right" (HNullify right) context
3130 }
src/Rel8/Schema/HTable/Identity.hs+16−28
@@ -1,17 +1,17 @@
11{-# language DataKinds #-}
2−{-# language GADTs #-}
3−{-# language PatternSynonyms #-}
2+{-# language FlexibleContexts #-}
43{-# language StandaloneKindSignatures #-}
54{-# language TypeFamilies #-}
5+{-# language UndecidableInstances #-}
66
77module Rel8.Schema.HTable.Identity
8− ( HIdentity( HIdentity, HType, unHIdentity )
9− , HType
8+ ( HIdentity( HIdentity, unHIdentity )
109 )
1110where
1211
1312-- base
1413import Data.Kind ( Type )
14+import Data.Type.Equality ( (:~:)( Refl ) )
1515import Prelude
1616
1717-- rel8
@@ -21,35 +21,23 @@ import Rel8.Schema.HTable
2121 , hfield, htabulate, htraverse, hdicts, hspecs
2222 )
2323import qualified Rel8.Schema.Kind as K
24−import Rel8.Schema.Spec ( Spec( Spec ), KnownSpec, specSing )
24+import Rel8.Schema.Null ( Sql )
25+import Rel8.Schema.Spec ( specification )
26+import Rel8.Type ( DBType )
2527
2628
27−type HType :: Type -> K.HTable
28−type HType a = HIdentity ('Spec '[] a)
29−
30−
31−pattern HType :: context ('Spec '[] a) -> HType a context
32−pattern HType a = HIdentity a
33−{-# COMPLETE HType #-}
34−
35−
36−type HIdentity :: Spec -> K.HTable
37−newtype HIdentity spec context = HIdentity
38− { unHIdentity :: context spec
29+type HIdentity :: Type -> K.HTable
30+newtype HIdentity a context = HIdentity
31+ { unHIdentity :: context a
3932 }
4033
4134
42−type HIdentityField :: Spec -> Spec -> Type
43−data HIdentityField _spec spec where
44− HIdentityField :: HIdentityField spec spec
45−
46−
47−instance KnownSpec spec => HTable (HIdentity spec) where
48− type HConstrainTable (HIdentity spec) c = c spec
49− type HField (HIdentity spec) = HIdentityField spec
35+instance Sql DBType a => HTable (HIdentity a) where
36+ type HConstrainTable (HIdentity a) constraint = constraint a
37+ type HField (HIdentity a) = (:~:) a
5038
51− hfield (HIdentity a) HIdentityField = a
52− htabulate f = HIdentity $ f HIdentityField
39+ hfield (HIdentity a) Refl = a
40+ htabulate f = HIdentity $ f Refl
5341 htraverse f (HIdentity a) = HIdentity <$> f a
5442 hdicts = HIdentity Dict
55− 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( SCons ) )
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 a)) = 'Spec (label : labels) 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 = SCons Proxy labels, ..}
5851
59−
60−hlabel :: (HTable t, KnownSymbol label)
61− => (forall labels a. ()
62− => context ('Spec labels a)
63− -> context ('Spec (label ': labels) 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 a. ()
74− => context ('Spec (label ': labels) a)
75− -> context ('Spec labels 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+2−3
@@ -15,17 +15,16 @@ import Prelude
1515
1616-- rel8
1717import Rel8.Schema.HTable ( HTable )
18−import Rel8.Schema.HTable.Identity ( HIdentity(..) )
18+import Rel8.Schema.HTable.Identity ( HIdentity )
1919import Rel8.Schema.HTable.Label ( HLabel )
2020import Rel8.Schema.HTable.Nullify ( HNullify )
2121import qualified Rel8.Schema.Kind as K
22−import Rel8.Schema.Spec ( Spec( Spec ) )
2322import Rel8.Type.Tag ( MaybeTag )
2423
2524
2625type HMaybeTable :: K.HTable -> K.HTable
2726data HMaybeTable table context = HMaybeTable
28− { htag :: HIdentity ('Spec '["isJust"] (Maybe MaybeTag)) context
27+ { htag :: HLabel "isJust" (HIdentity (Maybe MaybeTag)) context
2928 , hjust :: HLabel "Just" (HNullify table) context
3029 }
3130 deriving stock Generic
src/Rel8/Schema/HTable/Nullify.hs+47−32
@@ -10,6 +10,7 @@
1010{-# 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 a)) =
54− 'Spec labels (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, info, nullity} -> SSpec
60− { labels
61− , info
62− , nullity = case nullity of
65+ Spec {nullity, ..} -> Spec
66+ { nullity = case nullity of
6367 Null -> Null
6468 NotNull -> Null
65− }
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
6682
6783
6884hnulls :: HTable t
69− => (forall labels a. ()
70− => SSpec ('Spec labels a)
71− -> context ('Spec labels (Type.Nullify 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− spec@SSpec {} -> null spec
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 a. ()
80− => SSpec ('Spec labels a)
81− -> context ('Spec labels a)
82− -> context ('Spec labels (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 a. ()
93− => SSpec ('Spec labels a)
94− -> context ('Spec labels (Type.Nullify a))
95− -> m (context ('Spec labels 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+2−3
@@ -19,15 +19,14 @@ import Rel8.Schema.HTable.Identity ( HIdentity )
1919import Rel8.Schema.HTable.Label ( HLabel )
2020import Rel8.Schema.HTable.Nullify ( HNullify )
2121import qualified Rel8.Schema.Kind as K
22−import Rel8.Schema.Spec ( Spec( Spec ) )
2322import Rel8.Type.Tag ( MaybeTag )
2423
2524
2625type HTheseTable :: K.HTable -> K.HTable -> K.HTable
2726data HTheseTable here there context = HTheseTable
28− { hhereTag :: HIdentity ('Spec '["hasHere"] (Maybe MaybeTag)) context
27+ { hhereTag :: HLabel "hereTag" (HIdentity (Maybe MaybeTag)) context
2928 , hhere :: HLabel "Here" (HNullify here) context
30− , hthereTag :: HIdentity ('Spec '["hasThere"] (Maybe MaybeTag)) context
29+ , hthereTag :: HLabel "thereTag" (HIdentity (Maybe MaybeTag)) context
3130 , hthere :: HLabel "There" (HNullify there) context
3231 }
3332 deriving stock Generic
src/Rel8/Schema/HTable/Vectorize.hs+37−45
@@ -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
4853import Data.Zip ( Unzip, Zip, Zippy(..) )
49−import Rel8.FCF
50−import Rel8.Schema.HTable.MapTable
51−import GHC.Generics (Generic)
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 a)) = 'Spec labels (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 a. ()
96− => SSpec ('Spec labels a)
97− -> f (context ('Spec labels a))
98− -> context' ('Spec labels (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
107107hunvectorize :: (HTable t, Zip f, Vector list)
108− => (forall labels a. ()
109− => SSpec ('Spec labels a)
110− -> context ('Spec labels (list a))
111− -> f (context' ('Spec labels a)))
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 a. ()
123− => Nullity a
124− -> TypeInformation (Unnullify a)
125− -> context ('Spec labels (list a))
126− -> context ('Spec labels (list a))
127− -> context ('Spec labels (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 a. ()
140− => Nullity a
141− -> TypeInformation (Unnullify a)
142− -> context ('Spec labels [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/Kind.hs+6−15
@@ -1,8 +1,9 @@
11{-# language StandaloneKindSignatures #-}
22
33module Rel8.Schema.Kind
4− ( Context, Rel8able
5− , HContext, HTable
4+ ( Rel8able
5+ , Context
6+ , HTable
67 )
78where
89
@@ -10,23 +11,13 @@ 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
3223type Rel8able :: Type
src/Rel8/Schema/Name.hs+34−56
@@ -3,41 +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( N, unN )
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.Identity ( HIdentity( 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.Reify ( notReify )
35−import Rel8.Schema.Result ( Result )
36−import Rel8.Schema.Spec ( Spec( Spec ) )
3738import Rel8.Table
38− ( Table, Columns, Context, fromColumns, toColumns, reify, unreify
39+ ( Table, Columns, Context, fromColumns, toColumns
40+ , FromExprs, fromResult, toResult
41+ , Transpose
3942 )
40−import Rel8.Table.Recontextualize ( Recontextualize )
43+import Rel8.Table.Transpose ( Transposes )
4144import Rel8.Type ( DBType )
4245
4346
@@ -45,55 +48,30 @@ import Rel8.Type ( DBType )
4548-- schema definition. You can construct names by using the @OverloadedStrings@
4649-- extension and writing string literals. This is typically done when providing
4750-- a 'TableSchema' value.
48−type Name :: k -> Type
49−data Name a where
50− Name :: k ~ Type => !String -> Name (a :: k)
51−
52−
53−deriving stock instance Show (Name a)
54−
55−
56−instance k ~ Type => IsString (Name (a :: k)) where
57− fromString = Name
51+type Name :: K.Context
52+newtype Name a = Name String
53+ deriving stock Show
54+ deriving newtype IsString
5855
5956
6057instance Sql DBType a => Table Name (Name a) where
61− type Columns (Name a) = HType a
58+ type Columns (Name a) = HIdentity a
6259 type Context (Name a) = Name
60+ type FromExprs (Name a) = a
61+ type Transpose to (Name a) = to a
6362
64− toColumns a = HType (N a)
65− fromColumns (HType (N a)) = a
66− reify = notReify
67− unreify = notReify
68−
69−
70−instance Sql DBType a => Recontextualize Expr Name (Expr a) (Name a)
71−
72−
73−instance Sql DBType a => Recontextualize Result Name (Identity a) (Name a)
74−
75−
76−instance Sql DBType a => Recontextualize Name Expr (Name a) (Expr a)
77−
78−
79−instance Sql DBType a => Recontextualize Name Result (Name a) (Identity a)
80−
81−
82−instance Sql DBType a => Recontextualize Name Name (Name a) (Name a)
83−
84−
85−instance Interpretation Name where
86− data Col Name _spec where
87− N :: {unN :: !(Name a)} -> Col Name ('Spec labels a)
88−
89−
90−instance Labelable Name where
91− labeler (N a) = N a
92− unlabeler (N a) = N a
63+ toColumns a = HIdentity a
64+ fromColumns (HIdentity a) = a
65+ toResult a = HIdentity (Identity a)
66+ fromResult (HIdentity (Identity a)) = a
9367
9468
9569-- | @Selects a b@ means that @a@ is a schema (i.e., a 'Table' of 'Name's) for
9670-- the 'Expr' columns in @b@.
9771type Selects :: Type -> Type -> Constraint
98−class Recontextualize Name Expr names exprs => Selects names exprs
99−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/Reify.hsdeleted−74
@@ -1,74 +0,0 @@
1−{-# language AllowAmbiguousTypes #-}
2−{-# language EmptyCase #-}
3−{-# language DataKinds #-}
4−{-# language FlexibleInstances #-}
5−{-# language ScopedTypeVariables #-}
6−{-# language StandaloneKindSignatures #-}
7−{-# language TypeApplications #-}
8−{-# language TypeFamilies #-}
9−{-# language TypeOperators #-}
10−{-# language UndecidableInstances #-}
11−
12−module Rel8.Schema.Reify
13− ( Reify, Col( Reify ), hreify, hunreify
14− , UnwrapReify
15− , NotReify, notReify
16− )
17−where
18−
19−-- base
20−import Data.Kind ( Constraint )
21−import Data.Type.Equality ( (:~:)( Refl ) )
22−import Prelude
23−
24−-- rel8
25−import Rel8.Schema.Context ( Interpretation, Col )
26−import Rel8.Schema.Context.Label ( Labelable, labeler, unlabeler )
27−import Rel8.Schema.HTable ( HTable, hmap )
28−import Rel8.Schema.Kind ( Context )
29−
30−
31−type Reify :: Context -> Context
32−data Reify context a
33−
34−
35−instance Interpretation (Reify context) where
36− newtype Col (Reify context) spec = Reify (Col context spec)
37−
38−
39−instance Labelable context => Labelable (Reify context) where
40− labeler (Reify a) = Reify (labeler a)
41− unlabeler (Reify a) = Reify (unlabeler a)
42−
43−
44−hreify :: HTable t => t (Col context) -> t (Col (Reify context))
45−hreify = hmap Reify
46−
47−
48−hunreify :: HTable t => t (Col (Reify context)) -> t (Col context)
49−hunreify = hmap (\(Reify a) -> a)
50−
51−
52−type UnwrapReify :: Context -> Context
53−type family UnwrapReify context where
54− UnwrapReify (Reify context) = context
55−
56−
57−type IsReify :: Context -> Bool
58−type family IsReify context where
59− IsReify (Reify _) = 'True
60− IsReify _ = 'False
61−
62−
63−type NotReify :: Context -> Constraint
64−class IsReify context ~ 'False => NotReify context
65−instance IsReify context ~ 'False => NotReify context
66−
67−
68−notReify :: forall context ctx a. NotReify context => context :~: Reify ctx -> a
69−notReify refl = case lemma @context of
70− Refl -> case refl of
71−
72−
73−lemma :: NotReify context => IsReify context :~: 'False
74−lemma = Refl
src/Rel8/Schema/Result.hs+16−41
@@ -5,22 +5,20 @@
55{-# language TypeFamilies #-}
66
77module Rel8.Schema.Result
8− ( Col( R, unR ), Result
9− , relabel
8+ ( Result
109 , null, nullifier, unnullifier
1110 , vectorizer, unvectorizer
1211 )
1312where
1413
1514-- base
15+import Data.Functor.Identity ( Identity( Identity), runIdentity )
1616import Prelude hiding ( null )
1717
1818-- rel8
19−import Rel8.Schema.Context ( Interpretation( Col ) )
20−import Rel8.Schema.HTable.Identity ( HIdentity(..) )
2119import Rel8.Schema.Kind ( Context )
2220import Rel8.Schema.Null ( Nullify, Nullity( Null, NotNull ) )
23−import Rel8.Schema.Spec ( Spec( Spec ), SSpec(..) )
21+import Rel8.Schema.Spec ( Spec(..) )
2422
2523
2624-- | The @Result@ context is the context used for decoded query results.
@@ -28,52 +26,29 @@ import Rel8.Schema.Spec ( Spec( Spec ), SSpec(..) )
2826-- When a query is executed against a PostgreSQL database, Rel8 parses the
2927-- returned rows, decoding each row into the @Result@ context.
3028type Result :: Context
31−data Result a
29+type Result = Identity
3230
3331
34−instance Interpretation Result where
35− data Col Result _spec where
36− R :: {unR :: !a} -> Col Result ('Spec labels a)
32+null :: Result (Maybe a)
33+null = Identity Nothing
3734
3835
39−relabel :: ()
40− => HIdentity ('Spec labels a) (Col Result)
41− -> HIdentity ('Spec relabels a) (Col Result)
42−relabel (HIdentity (R a)) = HIdentity (R a)
43−
44−
45−null :: Col Result ('Spec labels (Maybe a))
46−null = R Nothing
47−
48−
49−nullifier :: ()
50− => SSpec ('Spec labels a)
51− -> Col Result ('Spec labels a)
52− -> Col Result ('Spec labels (Nullify a))
53−nullifier SSpec {nullity} (R a) = R $ case nullity of
36+nullifier :: Spec a -> Result a -> Result (Nullify a)
37+nullifier Spec {nullity} (Identity a) = Identity $ case nullity of
5438 Null -> a
5539 NotNull -> Just a
5640
5741
58−unnullifier :: ()
59− => SSpec ('Spec labels a)
60− -> Col Result ('Spec labels (Nullify a))
61− -> Maybe (Col Result ('Spec labels a))
62−unnullifier SSpec {nullity} (R a) =
42+unnullifier :: Spec a -> Result (Nullify a) -> Maybe (Result a)
43+unnullifier Spec {nullity} (Identity a) =
6344 case nullity of
64− Null -> pure $ R a
65− NotNull -> R <$> a
45+ Null -> pure $ Identity a
46+ NotNull -> Identity <$> a
6647
6748
68−vectorizer :: Functor f
69− => SSpec ('Spec labels a)
70− -> f (Col Result ('Spec labels a))
71− -> Col Result ('Spec labels (f a))
72−vectorizer _ = R . fmap unR
49+vectorizer :: Functor f => Spec a -> f (Result a) -> Result (f a)
50+vectorizer _ = Identity . fmap runIdentity
7351
7452
75−unvectorizer :: Functor f
76− => SSpec ('Spec labels a)
77− -> Col Result ('Spec labels (f a))
78− -> f (Col Result ('Spec labels a))
79−unvectorizer _ (R results) = R <$> results
53+unvectorizer :: Functor f => Spec a -> Result (f a) -> f (Result a)
54+unvectorizer _ (Identity results) = Identity <$> results
src/Rel8/Schema/Spec.hs+17−37
@@ -1,54 +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, 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 )
2016import Rel8.Schema.Null ( Nullity, Sql, Unnullify, nullable )
2117import Rel8.Type ( DBType, typeInformation )
2218import Rel8.Type.Information ( TypeInformation )
2319
2420
25−type Spec :: Type
26−data Spec = Spec Labels Type
21+type Spec :: Type -> Type
22+data Spec a = Spec
23+ { labels :: [String]
24+ , info :: TypeInformation (Unnullify a)
25+ , nullity :: Nullity a
26+ }
2727
2828
29−type SSpec :: Spec -> Type
30−data SSpec spec where
31− SSpec ::
32− { labels :: SLabels labels
33− , info :: TypeInformation (Unnullify a)
34− , nullity :: Nullity a
35− }
36− -> SSpec ('Spec labels a)
37−
38−
39−type KnownSpec :: Spec -> Constraint
40−class KnownSpec spec where
41− specSing :: SSpec spec
42−
43−
44−instance
45− ( KnownLabels labels
46− , Sql DBType a
47− )
48− => KnownSpec ('Spec labels a)
49− where
50− specSing = SSpec
51− { labels = labelsSing
52− , info = typeInformation
53− , nullity = nullable
54− }
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−89
@@ -1,89 +0,0 @@
1−{-# language ConstraintKinds #-}
2−{-# language DataKinds #-}
3−{-# language FlexibleInstances #-}
4−{-# language MultiParamTypeClasses #-}
5−{-# language NamedFieldPuns #-}
6−{-# language QuantifiedConstraints #-}
7−{-# language StandaloneKindSignatures #-}
8−{-# language TypeFamilies #-}
9−{-# language UndecidableInstances #-}
10−
11−module Rel8.Schema.Spec.ConstrainDBType
12− ( ConstrainDBType
13− , dbTypeNullity, dbTypeDict
14− , nullifier, unnullifier
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
25− ( Nullify, Unnullify
26− , Nullity( Null, NotNull )
27− , Sql, nullable
28− )
29−import Rel8.Schema.Spec ( Spec( Spec ), SSpec( SSpec, nullity ) )
30−
31−
32−type ConstrainDBType :: (Type -> Constraint) -> Spec -> Constraint
33−class
34− ( forall c labels a. ()
35− => (spec ~ 'Spec labels a)
36− => (forall x. (constraint x => c x)) => Sql c a
37− )
38− => ConstrainDBType constraint spec
39−instance
40− ( spec ~ 'Spec labels a
41− , Sql constraint a
42− )
43− => ConstrainDBType constraint spec
44−
45−
46−dbTypeNullity :: Dict (ConstrainDBType c) ('Spec l a) -> Nullity a
47−dbTypeNullity = step2 . step1
48− where
49− step1 :: Dict (ConstrainDBType c) ('Spec l a) -> Dict (Sql c) a
50− step1 Dict = Dict
51−
52− step2 :: Dict (Sql c) a -> Nullity a
53− step2 Dict = nullable
54−
55−
56−dbTypeDict :: Dict (ConstrainDBType c) ('Spec l a) -> Dict c (Unnullify a)
57−dbTypeDict = step2 . step1
58− where
59− step1 :: Dict (ConstrainDBType c) ('Spec l a) -> Dict (Sql c) a
60− step1 Dict = Dict
61−
62− step2 :: Dict (Sql c) a -> Dict c (Unnullify a)
63− step2 Dict = Dict
64−
65−
66−fromNullityDict :: Nullity a -> Dict c (Unnullify a) -> Dict (ConstrainDBType c) ('Spec l a)
67−fromNullityDict Null Dict = Dict
68−fromNullityDict NotNull Dict = Dict
69−
70−
71−nullifier :: ()
72− => SSpec ('Spec labels a)
73− -> Dict (ConstrainDBType c) ('Spec labels a)
74− -> Dict (ConstrainDBType c) ('Spec labels (Nullify a))
75−nullifier SSpec {} dict = case dbTypeDict dict of
76− Dict -> case dbTypeNullity dict of
77− Null -> Dict
78− NotNull -> Dict
79−
80−
81−unnullifier :: ()
82− => SSpec ('Spec labels a)
83− -> Dict (ConstrainDBType c) ('Spec labels (Nullify a))
84− -> Dict (ConstrainDBType c) ('Spec labels a)
85−unnullifier SSpec {nullity} dict = case dbTypeDict dict of
86− Dict -> case nullity of
87− Null -> Dict
88− NotNull -> case dbTypeNullity dict of
89− Null -> fromNullityDict nullity Dict
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+43−72
@@ -1,64 +1,59 @@
11{-# language DuplicateRecordFields #-}
2+{-# language FlexibleContexts #-}
23{-# language GADTs #-}
34{-# language NamedFieldPuns #-}
4−{-# language ScopedTypeVariables #-}
5+{-# language RecordWildCards #-}
56{-# language StandaloneKindSignatures #-}
6−{-# language TypeApplications #-}
7+{-# language StrictData #-}
78
89module Rel8.Statement.Insert
910 ( Insert(..)
10− , OnConflict(..)
1111 , insert
12+ , ppInsert
13+ , ppInto
1214 )
1315where
1416
1517-- base
16−import Control.Exception ( throwIO )
17−import Data.List.NonEmpty ( NonEmpty( (:|) ) )
18+import Data.Foldable ( toList )
1819import Data.Kind ( Type )
1920import Prelude
2021
2122-- hasql
22−import Hasql.Connection ( Connection )
23−import qualified Hasql.Decoders as Hasql
2423import qualified Hasql.Encoders as Hasql
25−import qualified Hasql.Session as Hasql
2624import qualified Hasql.Statement as Hasql
2725
2826-- opaleye
29−import qualified Opaleye.Internal.Manipulation as Opaleye
30−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 )
3131
3232-- rel8
33−import Rel8.Schema.Name ( Selects )
34−import Rel8.Schema.Table ( TableSchema )
35−import Rel8.Statement.Returning ( Returning( Projection, NumberOfRowsAffected ) )
36−import Rel8.Table ( fromColumns, toColumns )
37−import Rel8.Table.Opaleye ( castTable, table, unpackspec )
38−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 )
3941
4042-- text
4143import qualified Data.Text as Text ( pack )
4244import Data.Text.Encoding ( encodeUtf8 )
4345
4446
45−-- | @OnConflict@ allows you to add an @ON CONFLICT@ clause to an @INSERT@
46−-- statement.
47−type OnConflict :: Type
48−data OnConflict
49− = Abort -- ^ @ON CONFLICT ABORT@
50− | DoNothing -- ^ @ON CONFLICT DO NOTHING@
51−
52−
5347-- | The constituent parts of a SQL @INSERT@ statement.
5448type Insert :: Type -> Type
5549data Insert a where
5650 Insert :: Selects names exprs =>
5751 { into :: TableSchema names
5852 -- ^ Which table to insert into.
59− , rows :: [exprs]
60− -- ^ The rows to insert.
61− , onConflict :: OnConflict
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
6257 -- ^ What to do if the inserted rows conflict with data already in the
6358 -- table.
6459 , returning :: Returning names a
@@ -67,52 +62,28 @@ data Insert a where
6762 -> Insert a
6863
6964
70−-- | Run an @INSERT@ statement
71−insert :: Connection -> Insert a -> IO a
72−insert c Insert {into, rows, onConflict, returning} =
73− case (rows, returning) of
74− ([], NumberOfRowsAffected) -> pure 0
75− ([], Projection _) -> pure []
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
7672
77− (x:xs, NumberOfRowsAffected) -> Hasql.run session c >>= either throwIO pure
78− where
79− session = Hasql.statement () statement
80− statement = Hasql.Statement bytes params decode prepare
81− bytes = encodeUtf8 $ Text.pack sql
82− params = Hasql.noParams
83− decode = Hasql.rowsAffected
84− prepare = False
85− sql = Opaleye.arrangeInsertManySql into' rows' onConflict'
86− where
87− into' = table $ toColumns <$> into
88− rows' = toColumns <$> x :| xs
8973
90− (x:xs, Projection project) -> Hasql.run session c >>= either throwIO pure
91− where
92− session = Hasql.statement () statement
93− statement = Hasql.Statement bytes params decode prepare
94− bytes = encodeUtf8 $ Text.pack sql
95− params = Hasql.noParams
96− decode = decoder project
97− prepare = False
98− sql =
99− Opaleye.arrangeInsertManyReturningSql
100− unpackspec
101− into'
102− rows'
103− project'
104− onConflict'
105− where
106− into' = table $ toColumns <$> into
107− rows' = toColumns <$> x :| xs
108− project' = castTable . toColumns . project . fromColumns
74+ppInto :: Table Name a => TableSchema a -> Doc
75+ppInto table@TableSchema {columns} =
76+ ppTable table <+>
77+ parens (Opaleye.commaV ppColumn (toList (showNames columns)))
10978
110− where
111− onConflict' =
112− case onConflict of
113− DoNothing -> Just Opaleye.DoNothing
114− Abort -> Nothing
11579
116− decoder :: forall exprs projection a. Serializable projection a
117− => (exprs -> projection) -> Hasql.Result [a]
118− decoder _ = Hasql.rowList (parse @projection @a)
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+38−56
@@ -1,39 +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
23+-- pretty
24+import Text.PrettyPrint ( Doc, (<+>), ($$), text )
2725
2826-- rel8
2927import Rel8.Expr ( Expr )
30−import Rel8.Expr.Opaleye ( toColumn, toPrimExpr )
28+import Rel8.Query ( Query )
3129import Rel8.Schema.Name ( Selects )
32−import Rel8.Schema.Table ( TableSchema )
33−import Rel8.Statement.Returning ( Returning( Projection, NumberOfRowsAffected ) )
34−import Rel8.Table ( fromColumns, toColumns )
35−import Rel8.Table.Opaleye ( castTable, table, unpackspec )
36−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 )
3735
3836-- text
3937import qualified Data.Text as Text
@@ -46,9 +44,12 @@ data Update a where
4644 Update :: Selects names exprs =>
4745 { target :: TableSchema names
4846 -- ^ Which table to update.
49− , 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
5051 -- ^ How to update each selected row.
51− , updateWhere :: exprs -> Expr Bool
52+ , updateWhere :: from -> exprs -> Expr Bool
5253 -- ^ Which rows to select for update.
5354 , returning :: Returning names a
5455 -- ^ What to return from the @UPDATE@ statement.
@@ -56,46 +57,27 @@ data Update a where
5657 -> Update a
5758
5859
59−-- | Run an @UPDATE@ statement.
60−update :: Connection -> Update a -> IO a
61−update c Update {target, set, updateWhere, returning} =
62− case returning of
63− NumberOfRowsAffected -> Hasql.run session c >>= either throwIO pure
64− where
65− session = Hasql.statement () statement
66− statement = Hasql.Statement bytes params decode prepare
67− bytes = encodeUtf8 $ Text.pack sql
68− params = Hasql.noParams
69− decode = Hasql.rowsAffected
70− prepare = False
71− sql = Opaleye.arrangeUpdateSql target' set' where'
72− where
73− target' = table $ toColumns <$> target
74− set' = toColumns . set . fromColumns
75− 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
7672
77− Projection project -> Hasql.run session c >>= either throwIO pure
78− where
79− session = Hasql.statement () statement
80− statement = Hasql.Statement bytes params decode prepare
81− bytes = encodeUtf8 $ Text.pack sql
82− params = Hasql.noParams
83− decode = decoder project
84− prepare = False
85− sql =
86− Opaleye.arrangeUpdateReturningSql
87− unpackspec
88− target'
89− set'
90− where'
91− project'
92− where
93− target' = table $ toColumns <$> target
94− set' = toColumns . set . fromColumns
95− where' = toColumn . toPrimExpr . updateWhere . fromColumns
96− project' = castTable . toColumns . project . fromColumns
9773
74+-- | Run an @UPDATE@ statement.
75+update :: Update a -> Hasql.Statement () a
76+update u@Update {returning} = Hasql.Statement bytes params decode prepare
9877 where
99− decoder :: forall exprs projection a. Serializable projection a
100− => (exprs -> projection) -> Hasql.Result [a]
101− 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+88−252
@@ -1,77 +1,47 @@
11{-# language AllowAmbiguousTypes #-}
22{-# language DataKinds #-}
33{-# language DefaultSignatures #-}
4−{-# language DisambiguateRecordFields #-}
54{-# language FlexibleContexts #-}
65{-# language FlexibleInstances #-}
76{-# language FunctionalDependencies #-}
8−{-# language LambdaCase #-}
9−{-# language NamedFieldPuns #-}
107{-# language ScopedTypeVariables #-}
118{-# language StandaloneKindSignatures #-}
129{-# language TypeApplications #-}
1310{-# language TypeFamilies #-}
14−{-# language TypeOperators #-}
1511{-# language UndecidableInstances #-}
1612
1713module Rel8.Table
18− ( Table (Columns, Context, Unreify, toColumns, fromColumns, reify, unreify)
14+ ( Table
15+ ( Columns, Context, fromColumns, toColumns
16+ , FromExprs, fromResult, toResult
17+ , Transpose
18+ )
1919 , Congruent
20− , TTable, TColumns, TContext, TUnreify
20+ , TTable, TColumns, TContext, TFromExprs, TTranspose
21+ , TSerialize
2122 )
2223where
2324
2425-- base
25−import Data.Functor ( ($>) )
2626import Data.Functor.Identity ( Identity( Identity ) )
2727import Data.Kind ( Constraint, Type )
28−import Data.List.NonEmpty ( NonEmpty )
29−import Data.Proxy ( Proxy( Proxy ) )
30−import Data.Type.Equality ( (:~:)( Refl ) )
3128import GHC.Generics ( Generic, Rep, from, to )
3229import Prelude hiding ( null )
3330
3431-- rel8
3532import Rel8.FCF ( Eval, Exp )
36−import Rel8.Kind.Algebra ( KnownAlgebra )
37−import Rel8.Generic.Map ( GMap, GMappable, gmap, gunmap )
38−import Rel8.Generic.Table
39− ( GGTable, GGColumns, GGContext, ggfromColumns, ggtoColumns
40− , GAlgebra
33+import Rel8.Generic.Map ( Map )
34+import Rel8.Generic.Table.Record
35+ ( GTable, GColumns, GContext, gfromColumns, gtoColumns
36+ , GSerialize, gfromResult, gtoResult
4137 )
4238import Rel8.Generic.Record ( Record(..) )
43−import Rel8.Generic.Reify ( ARep )
44−import Rel8.Schema.Context.Label ( Labelable, labeler, unlabeler )
4539import Rel8.Schema.HTable ( HTable )
46−import Rel8.Schema.HTable.Either ( HEitherTable(..) )
47−import Rel8.Schema.HTable.Identity ( HIdentity(..), HType )
48−import Rel8.Schema.HTable.Label ( hlabel, hunlabel )
49−import Rel8.Schema.HTable.List ( HListTable )
50−import Rel8.Schema.HTable.Maybe ( HMaybeTable(..) )
51−import Rel8.Schema.HTable.NonEmpty ( HNonEmptyTable )
52−import Rel8.Schema.HTable.Nullify ( hnulls, hnullify, hunnullify )
53−import Rel8.Schema.HTable.These ( HTheseTable(..) )
54−import Rel8.Schema.HTable.Vectorize ( hvectorize, hunvectorize )
40+import Rel8.Schema.HTable.Identity ( HIdentity( HIdentity ) )
5541import qualified Rel8.Schema.Kind as K
5642import Rel8.Schema.Null ( Sql )
57−import Rel8.Schema.Reify
58− ( Reify, Col( Reify ), hreify, hunreify
59− , UnwrapReify
60− , notReify
61− )
62−import Rel8.Schema.Result
63− ( Col( R ), Result
64− , relabel
65− , null, nullifier, unnullifier
66− , vectorizer, unvectorizer
67− )
68−import Rel8.Schema.Spec ( KnownSpec )
43+import Rel8.Schema.Result ( Result )
6944import Rel8.Type ( DBType )
70−import Rel8.Type.Tag ( EitherTag( IsLeft, IsRight ), MaybeTag( IsJust ) )
71−
72−-- these
73−import Data.These ( These( This, That, These ) )
74−import Data.These.Combinators ( justHere, justThere )
7545
7646
7747-- | @Table@s are one of the foundational elements of Rel8, and describe data
@@ -86,90 +56,102 @@ import Data.These.Combinators ( justHere, justThere )
8656-- yourself, as anything that's an instance of 'Rel8.Rel8able' is always a
8757-- 'Table'.
8858type Table :: K.Context -> Type -> Constraint
89−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
9066 -- | The 'HTable' functor that describes the schema of this table.
9167 type Columns a :: K.HTable
9268
9369 -- | The common context that all columns use as an interpretation.
9470 type Context a :: K.Context
9571
96− type Unreify a :: Type
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
9777
98− toColumns :: a -> Columns a (Col context)
99− fromColumns :: Columns a (Col context) -> a
10078
101− reify :: context :~: Reify ctx -> Unreify a -> a
102− unreify :: context :~: Reify ctx -> a -> Unreify a
79+ toColumns :: a -> Columns a context
80+ fromColumns :: Columns a context -> a
10381
104− type Columns a = Eval (GGColumns (GAlgebra (Rep (Record a))) TColumns (Rep (Record a)))
105− type Context a = Eval (GGContext (GAlgebra (Rep (Record a))) TContext (Rep (Record a)))
106− type Unreify a = DefaultUnreify a
82+ fromResult :: Columns a Result -> FromExprs a
83+ toResult :: FromExprs a -> Columns a Result
84+
85+ type Columns a = GColumns TColumns (Rep (Record a))
86+ type Context a = GContext TContext (Rep (Record a))
87+ type FromExprs a = Map TFromExprs a
88+ type Transpose context a = Map (TTranspose context) a
10789
10890 default toColumns ::
10991 ( Generic (Record a)
110− , KnownAlgebra (GAlgebra (Rep (Record a)))
111− , Eval (GGTable (GAlgebra (Rep (Record a))) (TTable context) TColumns (Col context) (Rep (Record a)))
112− , Columns a ~ Eval (GGColumns (GAlgebra (Rep (Record a))) TColumns (Rep (Record a)))
113− , Context a ~ Eval (GGContext (GAlgebra (Rep (Record a))) TContext (Rep (Record a)))
92+ , GTable (TTable context) TColumns (Rep (Record a))
93+ , Columns a ~ GColumns TColumns (Rep (Record a))
11494 )
115− => a -> Columns a (Col context)
95+ => a -> Columns a context
11696 toColumns =
117− ggtoColumns
118− @(GAlgebra (Rep (Record a)))
119− @(TTable context)
120− @TColumns
121− id
122− id
123− toColumns .
97+ gtoColumns @(TTable context) @TColumns toColumns .
12498 from .
12599 Record
126100
127101 default fromColumns ::
128102 ( Generic (Record a)
129− , KnownAlgebra (GAlgebra (Rep (Record a)))
130− , Eval (GGTable (GAlgebra (Rep (Record a))) (TTable context) TColumns (Col context) (Rep (Record a)))
131− , Columns a ~ Eval (GGColumns (GAlgebra (Rep (Record a))) TColumns (Rep (Record a)))
132− , Context a ~ Eval (GGContext (GAlgebra (Rep (Record a))) TContext (Rep (Record a)))
103+ , GTable (TTable context) TColumns (Rep (Record a))
104+ , Columns a ~ GColumns TColumns (Rep (Record a))
133105 )
134− => Columns a (Col context) -> a
106+ => Columns a context -> a
135107 fromColumns =
136108 unrecord .
137109 to .
138− ggfromColumns
139− @(GAlgebra (Rep (Record a)))
140− @(TTable context)
141− @TColumns
142− id
143− id
144− fromColumns
110+ gfromColumns @(TTable context) @TColumns fromColumns
145111
146− default reify ::
147− ( Generic (Record a)
148− , Generic (Record (Unreify a))
149− , GMappable (TTable context) (Rep (Record a))
150− , Rep (Record (Unreify a)) ~ GMap TUnreify (Rep (Record a))
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))
151116 )
152− => context :~: Reify ctx -> Unreify a -> a
153− reify Refl =
154− unrecord .
155− to .
156− gunmap @(TTable context) (Proxy @TUnreify) (reify Refl) .
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) .
157125 from .
158126 Record
159127
160− default unreify ::
161− ( Generic (Record a)
162− , Generic (Record (Unreify a))
163− , GMappable (TTable context) (Rep (Record a))
164− , Rep (Record (Unreify a)) ~ GMap TUnreify (Rep (Record a))
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))
165132 )
166− => context :~: Reify ctx -> a -> Unreify a
167− unreify Refl =
133+ => Columns a Result -> FromExprs a
134+ fromResult =
168135 unrecord .
169136 to .
170− gmap @(TTable context) (Proxy @TUnreify) (unreify Refl) .
171− from .
172− Record
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
173155
174156
175157data TTable :: K.Context -> Type -> Exp Constraint
@@ -184,175 +166,32 @@ data TContext :: Type -> Exp K.Context
184166type instance Eval (TContext a) = Context a
185167
186168
187−data TUnreify :: Type -> Exp Type
188−type instance Eval (TUnreify a) = Unreify a
189−
190−
191−type DefaultUnreify :: Type -> Type
192−type family DefaultUnreify a where
193− DefaultUnreify (t a b c d e f g) =
194− t (Unreify a) (Unreify b) (Unreify c) (Unreify d) (Unreify e) (Unreify f) (Unreify g)
195− DefaultUnreify (t a b c d e f) =
196− t (Unreify a) (Unreify b) (Unreify c) (Unreify d) (Unreify e) (Unreify f)
197− DefaultUnreify (t a b c d e) =
198− t (Unreify a) (Unreify b) (Unreify c) (Unreify d) (Unreify e)
199− DefaultUnreify (t a b c d) =
200− t (Unreify a) (Unreify b) (Unreify c) (Unreify d)
201− DefaultUnreify (t a b c) = t (Unreify a) (Unreify b) (Unreify c)
202− DefaultUnreify (t a b) = t (Unreify a) (Unreify b)
203− DefaultUnreify (t a) = t (Unreify a)
204− DefaultUnreify a = ARep (GMap TUnreify (Rep a))
205−
169+data TFromExprs :: Type -> Exp Type
170+type instance Eval (TFromExprs a) = FromExprs a
206171
207−-- | Any 'HTable' is also a 'Table'.
208−instance HTable t => Table context (t (Col context)) where
209− type Columns (t (Col context)) = t
210− type Context (t (Col context)) = context
211− type Unreify (t (Col context)) = t (Col (UnwrapReify context))
212172
213− toColumns = id
214− fromColumns = id
173+data TTranspose :: K.Context -> Type -> Exp Type
174+type instance Eval (TTranspose context a) = Transpose context a
215175
216− reify Refl = hreify
217− unreify Refl = hunreify
218−
219−
220−-- | Any context is trivially a table.
221−instance KnownSpec spec => Table context (Col context spec) where
222− type Columns (Col context spec) = HIdentity spec
223− type Context (Col context spec) = context
224− type Unreify (Col context spec) = Col (UnwrapReify context) spec
225−
226− toColumns = HIdentity
227− fromColumns = unHIdentity
228−
229− reify Refl = Reify
230− unreify Refl (Reify a) = a
231176
177+data TSerialize :: Type -> Type -> Exp Constraint
178+type instance Eval (TSerialize expr a) =
179+ ( Table (Context expr) expr
180+ , a ~ FromExprs expr
181+ )
232182
233−instance Sql DBType a => Table Result (Identity a) where
234− type Columns (Identity a) = HType a
235− type Context (Identity a) = Result
236183
237− toColumns (Identity a) = HType (R a)
238− fromColumns (HType (R a)) = Identity a
239−
240− reify = notReify
241− unreify = notReify
242−
243−
244−instance (Table Result a, Table Result b) => Table Result (Either a b) where
245− type Columns (Either a b) = HEitherTable (Columns a) (Columns b)
246− type Context (Either a b) = Result
247−
248− toColumns = \case
249− Left table -> HEitherTable
250− { htag = HIdentity (R IsLeft)
251− , hleft = hlabel labeler (hnullify nullifier (toColumns table))
252− , hright = hlabel labeler (hnulls (const null))
253− }
254− Right table -> HEitherTable
255− { htag = HIdentity (R IsRight)
256− , hleft = hlabel labeler (hnulls (const null))
257− , hright = hlabel labeler (hnullify nullifier (toColumns table))
258− }
259−
260− fromColumns HEitherTable {htag, hleft, hright} = case htag of
261− HIdentity (R tag) -> case tag of
262− IsLeft -> maybe err (Left . fromColumns) $ hunnullify unnullifier (hunlabel unlabeler hleft)
263− IsRight -> maybe err (Right . fromColumns) $ hunnullify unnullifier (hunlabel unlabeler hright)
264− where
265− err = error "Either.fromColumns: mismatch between tag and data"
266−
267−
268−instance Table Result a => Table Result [a] where
269− type Columns [a] = HListTable (Columns a)
270− type Context [a] = Result
271−
272− toColumns = hvectorize vectorizer . fmap toColumns
273− fromColumns = fmap fromColumns . hunvectorize unvectorizer
274−
275−
276−instance Table Result a => Table Result (Maybe a) where
277− type Columns (Maybe a) = HMaybeTable (Columns a)
278− type Context (Maybe a) = Result
279−
280− toColumns = \case
281− Nothing -> HMaybeTable
282− { htag = HIdentity (R Nothing)
283− , hjust = hlabel labeler (hnulls (const null))
284− }
285− Just table -> HMaybeTable
286− { htag = HIdentity (R (Just IsJust))
287− , hjust = hlabel labeler (hnullify nullifier (toColumns table))
288− }
289−
290− fromColumns HMaybeTable {htag, hjust} = case htag of
291− HIdentity (R tag) -> tag $>
292− case hunnullify unnullifier (hunlabel unlabeler hjust) of
293− Nothing -> error "Maybe.fromColumns: mismatch between tag and data"
294− Just just -> fromColumns just
295−
296−
297−instance Table Result a => Table Result (NonEmpty a) where
298− type Columns (NonEmpty a) = HNonEmptyTable (Columns a)
299− type Context (NonEmpty a) = Result
300−
301− toColumns = hvectorize vectorizer . fmap toColumns
302− fromColumns = fmap fromColumns . hunvectorize unvectorizer
303−
304−
305−instance (Table Result a, Table Result b) => Table Result (These a b) where
306− type Columns (These a b) = HTheseTable (Columns a) (Columns b)
307− type Context (These a b) = Result
308−
309− toColumns tables = HTheseTable
310− { hhereTag = relabel hhereTag
311− , hhere = hlabel labeler (hunlabel unlabeler (toColumns hhere))
312− , hthereTag = relabel hthereTag
313− , hthere = hlabel labeler (hunlabel unlabeler (toColumns hthere))
314− }
315− where
316− HMaybeTable
317− { htag = hhereTag
318− , hjust = hhere
319− } = toColumns (justHere tables)
320− HMaybeTable
321− { htag = hthereTag
322− , hjust = hthere
323− } = toColumns (justThere tables)
324−
325− fromColumns HTheseTable {hhereTag, hhere, hthereTag, hthere} =
326− case (fromColumns mhere, fromColumns mthere) of
327− (Just a, Nothing) -> This (fromColumns a)
328− (Nothing, Just b) -> That (fromColumns b)
329− (Just a, Just b) -> These (fromColumns a) (fromColumns b)
330− _ -> error "These.fromColumns: mismatch between tags and data"
331− where
332− mhere = HMaybeTable
333− { htag = relabel hhereTag
334− , hjust = hlabel labeler (hunlabel unlabeler hhere)
335− }
336− mthere = HMaybeTable
337− { htag = relabel hthereTag
338− , hjust = hlabel labeler (hunlabel unlabeler hthere)
339− }
340−
341−
342−instance (Table context a, Table context b, Labelable context)
343− => Table context (a, b)
184+instance (Table context a, Table context b) => Table context (a, b)
344185
345186
346187instance
347188 ( Table context a, Table context b, Table context c
348− , Labelable context
349189 )
350190 => Table context (a, b, c)
351191
352192
353193instance
354194 ( Table context a, Table context b, Table context c, Table context d
355− , Labelable context
356195 )
357196 => Table context (a, b, c, d)
358197
@@ -360,7 +199,6 @@ instance
360199instance
361200 ( Table context a, Table context b, Table context c, Table context d
362201 , Table context e
363− , Labelable context
364202 )
365203 => Table context (a, b, c, d, e)
366204
@@ -368,7 +206,6 @@ instance
368206instance
369207 ( Table context a, Table context b, Table context c, Table context d
370208 , Table context e, Table context f
371− , Labelable context
372209 )
373210 => Table context (a, b, c, d, e, f)
374211
@@ -376,7 +213,6 @@ instance
376213instance
377214 ( Table context a, Table context b, Table context c, Table context d
378215 , Table context e, Table context f, Table context g
379− , Labelable context
380216 )
381217 => Table context (a, b, c, d, e, f, g)
382218
src/Rel8/Table/ADT.hs+33−65
@@ -7,13 +7,13 @@
77{-# language ScopedTypeVariables #-}
88{-# language StandaloneKindSignatures #-}
99{-# language TypeApplications #-}
10−{-# language TypeFamilies #-}
10+{-# language TypeFamilyDependencies #-}
1111{-# language UndecidableInstances #-}
1212{-# language UndecidableSuperClasses #-}
1313
1414module Rel8.Table.ADT
1515 ( ADT( ADT )
16− , ADTable, fromADT, toADT
16+ , ADTable
1717 , BuildableADT
1818 , BuildADT, buildADT
1919 , ConstructableADT
@@ -27,9 +27,7 @@ where
2727
2828-- base
2929import Data.Kind ( Constraint, Type )
30−import Data.Proxy ( Proxy( Proxy ) )
31−import Data.Type.Equality ( (:~:)( Refl ) )
32−import GHC.Generics ( Generic, Rep, from, to )
30+import GHC.Generics ( Generic, from, to )
3331import GHC.TypeLits ( Symbol )
3432import Prelude
3533
@@ -46,95 +44,65 @@ import Rel8.Generic.Construction
4644 , GGName, ggname
4745 , GGAggregate, ggaggregate
4846 )
49−import Rel8.Generic.Map ( GMappable, GMap, gmap, gunmap )
50−import Rel8.Generic.Record ( GRecordable, GRecord, grecord, gunrecord )
47+import Rel8.Generic.Record ( Record( Record ), unrecord )
5148import Rel8.Generic.Rel8able
5249 ( Rel8able
5350 , GRep, GColumns, gfromColumns, gtoColumns
54− , greify, gunreify
51+ , GFromExprs, gfromResult, gtoResult
52+ , TSerialize, deserialize, serialize
5553 )
5654import qualified Rel8.Generic.Table.ADT as G
5755import qualified Rel8.Kind.Algebra as K
58−import Rel8.Schema.Context ( Col )
5956import Rel8.Schema.HTable ( HTable )
6057import qualified Rel8.Schema.Kind as K
6158import Rel8.Schema.Name ( Name )
62−import Rel8.Schema.Reify ( Col( Reify ), Reify, hreify, hunreify )
6359import Rel8.Schema.Result ( Result )
64−import Rel8.Table
65− ( Table
66− , fromColumns, toColumns, reify, unreify
67− , TTable, TColumns, TUnreify
68− )
60+import Rel8.Table ( Table, TColumns )
6961
7062
7163type ADT :: K.Rel8able -> K.Rel8able
72−newtype ADT t context = ADT (GColumnsADT t (Col context))
64+newtype ADT t context = ADT (GColumnsADT t context)
7365
7466
7567instance ADTable t => Rel8able (ADT t) where
7668 type GColumns (ADT t) = GColumnsADT t
69+ type GFromExprs (ADT t) = t Result
7770
78− gfromColumns = ADT
79− gtoColumns (ADT a) = a
80−
81− greify (ADT a) = ADT (hreify a)
82− gunreify (ADT a) = ADT (hunreify a)
83−
71+ gfromColumns _ = ADT
72+ gtoColumns _ (ADT a) = a
8473
85−instance (ADTable t, context ~ Result) => Generic (ADT t context) where
86− type Rep (ADT t context) = Rep (t context)
87−
88− from =
89− gmap @(TTable (Reify Result)) (Proxy @TUnreify) (unreify Refl) .
90− gunrecord @(Rep (t (Reify Result))) .
91− G.gfromColumnsADT
92− @(TTable (Reify Result))
93− @TColumns
94− (\(Reify a) -> a)
95− Reify
96− fromColumns .
97− hreify .
98− (\(ADT a) -> a)
99−
100− to =
101− ADT .
102− hunreify .
103− G.gtoColumnsADT
104− @(TTable (Reify Result))
74+ gfromResult =
75+ unrecord .
76+ to .
77+ G.gfromResultADT
78+ @TSerialize
10579 @TColumns
106− (\(Reify a) -> a)
107− Reify
108− toColumns .
109− grecord @(Rep (t (Reify Result))) .
110− gunmap @(TTable (Reify Result)) (Proxy @TUnreify) (reify Refl)
80+ @(Eval (ADTRep t Expr))
81+ @(Eval (ADTRep t Result))
82+ (\(_ :: proxy x) -> deserialize @_ @x)
11183
112−
113−fromADT :: ADTable t => ADT t Result -> t Result
114−fromADT = to . from
115−
116−
117−toADT :: ADTable t => t Result -> ADT t Result
118−toADT = to . from
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
11993
12094
12195type ADTable :: K.Rel8able -> Constraint
12296class
123− ( Generic (t Result)
97+ ( Generic (Record (t Result))
12498 , HTable (GColumnsADT t)
125− , G.GTableADT (TTable (Reify Result)) TColumns (Col (Reify Result)) (GRecord (Rep (t (Reify Result))))
126− , GRecordable (Rep (t (Reify Result)))
127− , GMappable (TTable (Reify Result)) (Rep (t (Reify Result)))
128− , GMap TUnreify (Rep (t (Reify Result))) ~ Rep (t Result)
99+ , G.GSerializeADT TSerialize TColumns (Eval (ADTRep t Expr)) (Eval (ADTRep t Result))
129100 )
130101 => ADTable t
131102instance
132− ( Generic (t Result)
103+ ( Generic (Record (t Result))
133104 , HTable (GColumnsADT t)
134− , G.GTableADT (TTable (Reify Result)) TColumns (Col (Reify Result)) (GRecord (Rep (t (Reify Result))))
135− , GRecordable (Rep (t (Reify Result)))
136− , GMappable (TTable (Reify Result)) (Rep (t (Reify Result)))
137− , GMap TUnreify (Rep (t (Reify Result))) ~ Rep (t Result)
105+ , G.GSerializeADT TSerialize TColumns (Eval (ADTRep t Expr)) (Eval (ADTRep t Result))
138106 )
139107 => ADTable t
140108
@@ -202,4 +170,4 @@ type instance Eval (ADTRep t context) = GRep t context
202170
203171
204172type GColumnsADT :: K.Rel8able -> K.HTable
205−type GColumnsADT t = G.GColumnsADT TColumns (GRep t (Reify Result))
173+type GColumnsADT t = G.GColumnsADT TColumns (GRep t Expr)
src/Rel8/Table/Aggregate.hs+24−13
@@ -16,8 +16,8 @@ import Data.Functor.Identity ( Identity( Identity ) )
1616import Prelude
1717
1818-- rel8
19−import Rel8.Aggregate ( Aggregate, Aggregates, Col( A ) )
20−import Rel8.Expr ( Expr, Col( E ) )
19+import Rel8.Aggregate ( Aggregate, Aggregates )
20+import Rel8.Expr ( Expr )
2121import Rel8.Expr.Aggregate
2222 ( groupByExpr
2323 , slistAggExpr
@@ -26,8 +26,8 @@ import Rel8.Expr.Aggregate
2626import Rel8.Schema.Dict ( Dict( Dict ) )
2727import Rel8.Schema.HTable ( HTable, hfield, htabulate )
2828import Rel8.Schema.HTable.Vectorize ( hvectorize )
29−import Rel8.Schema.Spec ( SSpec( SSpec, info ) )
30−import Rel8.Schema.Spec.ConstrainDBType ( ConstrainDBType )
29+import Rel8.Schema.Null ( Sql )
30+import Rel8.Schema.Spec ( Spec( Spec, info ) )
3131import Rel8.Table ( toColumns, fromColumns )
3232import Rel8.Table.Eq ( EqTable, eqTable )
3333import Rel8.Table.List ( ListTable )
@@ -37,17 +37,28 @@ import Rel8.Type.Eq ( DBEq )
3737
3838-- | Group equal tables together. This works by aggregating each column in the
3939-- given table with 'groupByExpr'.
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+-- @
4052groupBy :: forall exprs aggregates. (EqTable exprs, Aggregates aggregates exprs)
4153 => exprs -> aggregates
4254groupBy = fromColumns . hgroupBy (eqTable @exprs) . toColumns
4355
4456
45−hgroupBy :: HTable t
46− => t (Dict (ConstrainDBType DBEq)) -> t (Col Expr) -> t (Col Aggregate)
47−hgroupBy eqs exprs = fromColumns $ htabulate $ \field ->
57+hgroupBy :: HTable t => t (Dict (Sql DBEq)) -> t Expr -> t Aggregate
58+hgroupBy eqs exprs = htabulate $ \field ->
4859 case hfield eqs field of
4960 Dict -> case hfield exprs field of
50− E expr -> A $ groupByExpr expr
61+ expr -> groupByExpr expr
5162
5263
5364-- | Aggregate rows into a single row containing an array of all aggregated
@@ -60,22 +71,22 @@ hgroupBy eqs exprs = fromColumns $ htabulate $ \field ->
6071-- items:
6172--
6273-- @
63−-- ordersWithItems :: Query (Order Expr, ListTable (Item Expr))
74+-- ordersWithItems :: Query (Order Expr, ListTable Expr (Item Expr))
6475-- ordersWithItems = do
6576-- order <- each orderSchema
6677-- items <- aggregate $ listAgg <$> itemsFromOrder order
6778-- return (order, items)
6879-- @
69−listAgg :: Aggregates aggregates exprs => exprs -> ListTable aggregates
80+listAgg :: Aggregates aggregates exprs => exprs -> ListTable Aggregate aggregates
7081listAgg (toColumns -> exprs) = fromColumns $
7182 hvectorize
72− (\SSpec {info} (Identity (E a)) -> A $ slistAggExpr info a)
83+ (\Spec {info} (Identity a) -> slistAggExpr info a)
7384 (pure exprs)
7485
7586
7687-- | Like 'listAgg', but the result is guaranteed to be a non-empty list.
77−nonEmptyAgg :: Aggregates aggregates exprs => exprs -> NonEmptyTable aggregates
88+nonEmptyAgg :: Aggregates aggregates exprs => exprs -> NonEmptyTable Aggregate aggregates
7889nonEmptyAgg (toColumns -> exprs) = fromColumns $
7990 hvectorize
80− (\SSpec {info} (Identity (E a)) -> A $ snonEmptyAggExpr info a)
91+ (\Spec {info} (Identity a) -> snonEmptyAggExpr info a)
8192 (pure exprs)
src/Rel8/Table/Bool.hs+5−6
@@ -13,7 +13,7 @@ where
1313import Prelude
1414
1515-- rel8
16−import Rel8.Expr ( Expr, Col( E, unE ) )
16+import Rel8.Expr ( Expr )
1717import Rel8.Expr.Bool ( boolExpr, caseExpr )
1818import Rel8.Expr.Null ( isNull, unsafeUnnullify )
1919import Rel8.Schema.HTable ( htabulate, hfield )
@@ -28,8 +28,7 @@ bool :: Table Expr a => a -> a -> Expr Bool -> a
2828bool (toColumns -> false) (toColumns -> true) condition =
2929 fromColumns $ htabulate $ \field ->
3030 case (hfield false field, hfield true field) of
31− (E falseExpr, E trueExpr) ->
32− E (boolExpr falseExpr trueExpr condition)
31+ (falseExpr, trueExpr) -> boolExpr falseExpr trueExpr condition
3332{-# INLINABLE bool #-}
3433
3534
@@ -39,9 +38,9 @@ bool (toColumns -> false) (toColumns -> true) condition =
3938case_ :: Table Expr a => [(Expr Bool, a)] -> a -> a
4039case_ (map (fmap toColumns) -> branches) (toColumns -> fallback) =
4140 fromColumns $ htabulate $ \field -> case hfield fallback field of
42− E fallbackExpr ->
43− case map (fmap (unE . (`hfield` field))) branches of
44− branchExprs -> E (caseExpr branchExprs fallbackExpr)
41+ fallbackExpr ->
42+ case map (fmap (`hfield` field)) branches of
43+ branchExprs -> caseExpr branchExprs fallbackExpr
4544
4645
4746-- | Like 'maybe', but to eliminate @null@.
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+126−131
@@ -18,46 +18,44 @@ module Rel8.Table.Either
1818 ( EitherTable(..)
1919 , eitherTable, leftTable, rightTable
2020 , isLeftTable, isRightTable
21+ , aggregateEitherTable
2122 , nameEitherTable
2223 )
2324where
2425
2526-- base
26−import Control.Applicative ( liftA2 )
2727import Data.Bifunctor ( Bifunctor, bimap )
28−import Data.Functor.Identity ( runIdentity )
28+import Data.Functor.Identity ( Identity( Identity ) )
2929import Data.Kind ( Type )
3030import Prelude hiding ( undefined )
3131
32+-- comonad
33+import Control.Comonad ( extract )
34+
3235-- rel8
36+import Rel8.Aggregate ( Aggregate )
3337import Rel8.Expr ( Expr )
38+import Rel8.Expr.Aggregate ( groupByExpr )
3439import Rel8.Expr.Serialize ( litExpr )
35−import Rel8.Schema.Context.Label
36− ( Labelable
37− , HLabelable, hlabeler, hunlabeler
38− )
39−import Rel8.Schema.Context.Nullify
40− ( Nullifiable, ConstrainTag
41− , HNullifiable, HConstrainTag
42− , hencodeTag, hdecodeTag
43− , hnullifier, hunnullifier
44− )
45−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 ) )
4643import Rel8.Schema.HTable.Either ( HEitherTable(..) )
4744import Rel8.Schema.HTable.Identity ( HIdentity(..) )
4845import Rel8.Schema.HTable.Label ( hlabel, hunlabel )
49−import Rel8.Schema.HTable.Nullify ( hnullify, hunnullify )
46+import qualified Rel8.Schema.Kind as K
5047import Rel8.Schema.Name ( Name )
5148import Rel8.Table
5249 ( Table, Columns, Context, fromColumns, toColumns
53− , reify, unreify
50+ , FromExprs, fromResult, toResult
51+ , Transpose
5452 )
5553import Rel8.Table.Bool ( bool )
5654import Rel8.Table.Eq ( EqTable, eqTable )
55+import Rel8.Table.Nullify ( Nullify, aggregateNullify, guard )
5756import Rel8.Table.Ord ( OrdTable, ordTable )
58−import Rel8.Table.Recontextualize ( Recontextualize )
59−import Rel8.Table.Serialize ( FromExprs, ToExprs, fromResult, toResult )
60−import Rel8.Table.Tag ( Tag(..), fromExpr, fromName )
57+import Rel8.Table.Projection ( Biprojectable, Projectable, biproject, project )
58+import Rel8.Table.Serialize ( ToExprs )
6159import Rel8.Table.Undefined ( undefined )
6260import Rel8.Type.Tag ( EitherTag( IsLeft, IsRight ), isLeft, isRight )
6361
@@ -72,119 +70,162 @@ import Data.Functor.Bind ( Bind, (>>-) )
7270--
7371-- An @EitherTable@ is operationally the same as Haskell's 'Either' type, but
7472-- adapted to work with Rel8.
75−type EitherTable :: Type -> Type -> Type
76−data EitherTable a b = EitherTable
77− { tag :: Tag "isRight" EitherTag
78− , left :: a
79− , right :: b
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
8078 }
8179 deriving stock Functor
8280
8381
84−instance Bifunctor EitherTable where
85− 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+
8686
87+instance Nullifiable context => Bifunctor (EitherTable context) where
88+ bimap f g (EitherTable tag a b) = EitherTable tag (fmap f a) (fmap g b)
8789
88−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
8996 EitherTable tag l1 f <.> EitherTable tag' l2 a =
90− EitherTable (tag <> tag') (bool l1 l2 (isLeft (expr tag))) (f a)
97+ EitherTable (tag <> tag') (bool l1 l2 (isLeft tag)) (f <.> a)
9198
9299
93−instance Table Expr a => Applicative (EitherTable a) where
100+instance (context ~ Expr, Table Expr a) => Applicative (EitherTable context a) where
94101 pure = rightTable
95102 (<*>) = (<.>)
96103
97104
98−instance Table Expr a => Bind (EitherTable a) where
99− 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
100107 EitherTable tag' l2 b ->
101− EitherTable (tag <> tag') (bool l1 l2 (isRight (expr tag))) b
108+ EitherTable (tag <> tag') (bool l1 l2 (isRight tag)) b
102109
103110
104−instance Table Expr a => Monad (EitherTable a) where
111+instance (context ~ Expr, Table Expr a) => Monad (EitherTable context a) where
105112 (>>=) = (>>-)
106113
107114
108−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
109118 a <> b = bool a b (isRightTable a)
110119
111120
112121instance
113122 ( Table context a, Table context b
114− , Labelable context, Nullifiable context, ConstrainTag context EitherTag
115− ) =>
116− Table context (EitherTable a b)
117− where
118− type Columns (EitherTable a b) = HEitherTable (Columns a) (Columns b)
119− type Context (EitherTable a b) = Context a
120−
121− toColumns = toColumns2 toColumns toColumns
122− fromColumns = fromColumns2 fromColumns fromColumns
123− reify = liftA2 bimap reify reify
124− unreify = liftA2 bimap unreify unreify
125−
126−
127−instance
128− ( Nullifiable from, Labelable from, ConstrainTag from EitherTag
129− , Nullifiable to, Labelable to, ConstrainTag to EitherTag
130− , Recontextualize from to a1 b1
131− , Recontextualize from to a2 b2
123+ , Reifiable context, context ~ context'
132124 )
133− => Recontextualize from to (EitherTable a1 a2) (EitherTable b1 b2)
134−
135−
136−instance (EqTable a, EqTable b) => EqTable (EitherTable a b) where
137− eqTable = toColumns2 id id (rightTableWith (eqTable @a) (eqTable @b))
138−
139−
140−instance (OrdTable a, OrdTable b) => OrdTable (EitherTable a b) where
141− ordTable = toColumns2 id id (rightTableWith (ordTable @a) (ordTable @b))
125+ => Table context' (EitherTable context a b)
126+ where
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+ }
142173
143174
144−type instance FromExprs (EitherTable a b) = Either (FromExprs a) (FromExprs 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+ }
145183
146184
147−instance (ToExprs exprs1 a, ToExprs exprs2 b, x ~ EitherTable exprs1 exprs2) =>
185+instance (ToExprs exprs1 a, ToExprs exprs2 b, x ~ EitherTable Expr exprs1 exprs2) =>
148186 ToExprs x (Either a b)
149− where
150− fromResult =
151− bimap (fromResult @exprs1) (fromResult @exprs2) .
152− fromColumns
153− toResult =
154− toColumns .
155− bimap (toResult @exprs1) (toResult @exprs2)
156187
157188
158189-- | Test if an 'EitherTable' is a 'leftTable'.
159−isLeftTable :: EitherTable a b -> Expr Bool
160−isLeftTable = isLeft . expr . tag
190+isLeftTable :: EitherTable Expr a b -> Expr Bool
191+isLeftTable EitherTable {tag} = isLeft tag
161192
162193
163194-- | Test if an 'EitherTable' is a 'rightTable'.
164−isRightTable :: EitherTable a b -> Expr Bool
165−isRightTable = isRight . expr . tag
195+isRightTable :: EitherTable Expr a b -> Expr Bool
196+isRightTable EitherTable {tag} = isRight tag
166197
167198
168199-- | Pattern match/eliminate an 'EitherTable', by providing mappings from a
169200-- 'leftTable' and 'rightTable'.
170201eitherTable :: Table Expr c
171− => (a -> c) -> (b -> c) -> EitherTable a b -> c
202+ => (a -> c) -> (b -> c) -> EitherTable Expr a b -> c
172203eitherTable f g EitherTable {tag, left, right} =
173− bool (f left) (g right) (isRight (expr tag))
204+ bool (f (extract left)) (g (extract right)) (isRight tag)
174205
175206
176207-- | Construct a left 'EitherTable'. Like 'Left'.
177−leftTable :: Table Expr b => a -> EitherTable a b
178−leftTable a = EitherTable (fromExpr (litExpr IsLeft)) a undefined
208+leftTable :: Table Expr b => a -> EitherTable Expr a b
209+leftTable a = EitherTable (litExpr IsLeft) (pure a) undefined
179210
180211
181212-- | Construct a right 'EitherTable'. Like 'Right'.
182−rightTable :: Table Expr a => b -> EitherTable a b
183−rightTable = rightTableWith undefined
184−
185−
186−rightTableWith :: a -> b -> EitherTable a b
187−rightTableWith = EitherTable (fromExpr (litExpr IsRight))
213+rightTable :: Table Expr a => b -> EitherTable Expr a b
214+rightTable = EitherTable (litExpr IsRight) undefined . pure
215+
216+
217+-- | Lift a pair of aggregating functions to operate on an 'EitherTable'.
218+-- @leftTable@s and @rightTable@s are grouped separately.
219+aggregateEitherTable :: ()
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
228+ }
188229
189230
190231-- | Construct a 'EitherTable' in the 'Name' context. This can be useful if you
@@ -198,51 +239,5 @@ nameEitherTable
198239 -- ^ Names of the columns in the @a@ table.
199240 -> b
200241 -- ^ Names of the columns in the @b@ table.
201− -> EitherTable a b
202−nameEitherTable = EitherTable . fromName
203−
204−
205−toColumns2 ::
206− ( HTable t
207− , HTable u
208− , HConstrainTag context EitherTag
209− , HLabelable context
210− , HNullifiable context
211− )
212− => (a -> t context)
213− -> (b -> u context)
214− -> EitherTable a b
215− -> HEitherTable t u context
216−toColumns2 f g EitherTable {tag, left, right} = HEitherTable
217− { htag
218− , hleft = hlabel hlabeler $ hnullify (hnullifier tag isLeft) $ f left
219− , hright = hlabel hlabeler $ hnullify (hnullifier tag isRight) $ g right
220− }
221− where
222− htag = HIdentity (hencodeTag tag)
223−
224−
225−fromColumns2 ::
226− ( HTable t
227− , HTable u
228− , HConstrainTag context EitherTag
229− , HLabelable context
230− , HNullifiable context
231− )
232− => (t context -> a)
233− -> (u context -> b)
234− -> HEitherTable t u context
235− -> EitherTable a b
236−fromColumns2 f g HEitherTable {htag, hleft, hright} = EitherTable
237− { tag
238− , left = f $ runIdentity $
239− hunnullify (\a -> pure . hunnullifier a) $
240− hunlabel hunlabeler
241− hleft
242− , right = g $ runIdentity $
243− hunnullify (\a -> pure . hunnullifier a) $
244− hunlabel hunlabeler
245− hright
246− }
247− where
248− tag = hdecodeTag $ unHIdentity htag
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
@@ -28,24 +27,16 @@ import GHC.Generics ( Rep )
2827import Prelude
2928
3029-- rel8
31−import Rel8.Expr ( Expr, Col( E ) )
30+import Rel8.Expr ( Expr )
3231import Rel8.Expr.Bool ( (||.), (&&.) )
3332import Rel8.Expr.Eq ( (==.), (/=.) )
3433import Rel8.FCF ( Eval, Exp )
3534import Rel8.Generic.Record ( Record )
36−import Rel8.Generic.Table
37− ( GGTable, GGColumns, ggtable
38− , GAlgebra
39− )
40−import Rel8.Kind.Algebra ( KnownAlgebra )
35+import Rel8.Generic.Table.Record ( GTable, GColumns, gtable )
4136import Rel8.Schema.Dict ( Dict( Dict ) )
42−import Rel8.Schema.HTable
43− ( HTable, HConstrainTable
44− , htabulateA, hfield, hdicts
45− )
46−import Rel8.Schema.HTable.Identity ( HIdentity( HType ) )
37+import Rel8.Schema.HTable ( htabulateA, hfield )
38+import Rel8.Schema.HTable.Identity ( HIdentity( HIdentity ) )
4739import Rel8.Schema.Null ( Sql )
48−import Rel8.Schema.Spec.ConstrainDBType ( ConstrainDBType, nullifier )
4940import Rel8.Table ( Table, Columns, toColumns, TColumns )
5041import Rel8.Type.Eq ( DBEq )
5142
@@ -55,22 +46,14 @@ import Rel8.Type.Eq ( DBEq )
5546-- means "all columns in a 'Table' have an instance of 'DBEq'".
5647type EqTable :: Type -> Constraint
5748class Table Expr a => EqTable a where
58− eqTable :: Columns a (Dict (ConstrainDBType DBEq))
49+ eqTable :: Columns a (Dict (Sql DBEq))
5950
6051 default eqTable ::
61− ( KnownAlgebra (GAlgebra (Rep (Record a)))
62− , Eval (GGTable (GAlgebra (Rep (Record a))) TEqTable TColumns (Dict (ConstrainDBType DBEq)) (Rep (Record a)))
63− , Columns a ~ Eval (GGColumns (GAlgebra (Rep (Record a))) TColumns (Rep (Record a)))
52+ ( GTable TEqTable TColumns (Rep (Record a))
53+ , Columns a ~ GColumns TColumns (Rep (Record a))
6454 )
65− => Columns a (Dict (ConstrainDBType DBEq))
66− eqTable =
67− ggtable
68− @(GAlgebra (Rep (Record a)))
69− @TEqTable
70− @TColumns
71− @(Rep (Record a))
72− table
73− nullifier
55+ => Columns a (Dict (Sql DBEq))
56+ eqTable = gtable @TEqTable @TColumns @(Rep (Record a)) table
7457 where
7558 table (_ :: proxy x) = eqTable @x
7659
@@ -79,18 +62,8 @@ data TEqTable :: Type -> Exp Constraint
7962type instance Eval (TEqTable a) = EqTable a
8063
8164
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− (E a, E 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− (E a, E 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.hs+65−105
@@ -13,7 +13,7 @@
1313
1414module Rel8.Table.HKD
1515 ( HKD( HKD )
16− , HKDable, fromHKD, toHKD, HKDT(..)
16+ , HKDable
1717 , BuildableHKD
1818 , BuildHKD, buildHKD
1919 , ConstructableHKD
@@ -27,9 +27,6 @@ where
2727
2828-- base
2929import Data.Kind ( Constraint, Type )
30−import Data.Proxy ( Proxy( Proxy ) )
31−import Data.Type.Equality ( (:~:)( Refl ) )
32−import Data.Void ( Void )
3330import GHC.Generics ( Generic, Rep, from, to )
3431import GHC.TypeLits ( Symbol )
3532import Prelude
@@ -49,163 +46,126 @@ import Rel8.Generic.Construction
4946 , GGName, ggname
5047 , GGAggregate, ggaggregate
5148 )
52−import Rel8.Generic.Map ( GMap, GMappable, gmap, gunmap )
53−import Rel8.Generic.Record ( GRecord, GRecordable, grecord, gunrecord )
49+import Rel8.Generic.Map ( GMap )
50+import Rel8.Generic.Record
51+ ( GRecord, GRecordable, grecord, gunrecord
52+ , Record( Record ), unrecord
53+ )
5454import Rel8.Generic.Rel8able
5555 ( Rel8able
5656 , GColumns, gfromColumns, gtoColumns
57− , greify, gunreify
58− , TUnreifyContext
57+ , GFromExprs, gfromResult, gtoResult
5958 )
6059import Rel8.Generic.Table
61− ( GGTable, GGColumns, GGContext, ggfromColumns, ggtoColumns
62− , GAlgebra
60+ ( GGSerialize, GGColumns, GAlgebra, ggfromResult, ggtoResult
6361 )
64−import Rel8.Schema.Context ( Col )
62+import Rel8.Generic.Table.Record ( GTable, GContext )
63+import qualified Rel8.Generic.Table.Record as G
6564import qualified Rel8.Schema.Kind as K
6665import Rel8.Schema.HTable ( HTable )
6766import Rel8.Schema.Name ( Name )
68−import Rel8.Schema.Reify ( Col( Reify ), Reify, hreify, hunreify, notReify )
6967import Rel8.Schema.Result ( Result )
7068import Rel8.Table
71− ( Table, Columns, Context, Unreify
72− , fromColumns, toColumns, reify, unreify
73− , TTable, TColumns, TUnreify
69+ ( Table, fromColumns, toColumns, fromResult, toResult
70+ , TTable, TColumns, TContext
71+ , TSerialize
7472 )
75−import Rel8.Table.Serialize ( ToExprs, fromResult, toResult )
7673
7774
7875type GColumnsHKD :: Type -> K.HTable
7976type GColumnsHKD a =
80− Eval (GGColumns (GAlgebra (Rep a)) TColumns (GRecord (GMap (TColumn (Reify Result)) (Rep a))))
77+ Eval (GGColumns (GAlgebra (Rep a)) TColumns (GRecord (GMap (TColumn Expr) (Rep a))))
8178
8279
8380type HKD :: Type -> K.Rel8able
84−newtype HKD a f = HKD (GColumnsHKD a (Col f))
81+newtype HKD a f = HKD (GColumnsHKD a f)
8582
8683
8784instance HKDable a => Rel8able (HKD a) where
8885 type GColumns (HKD a) = GColumnsHKD a
86+ type GFromExprs (HKD a) = a
8987
90− gfromColumns = HKD
91− gtoColumns (HKD a) = a
88+ gfromColumns _ = HKD
89+ gtoColumns _ (HKD a) = a
9290
93− greify (HKD a) = HKD (hreify a)
94− gunreify (HKD a) = HKD (hunreify a)
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
95112
96113
97114instance
98− ( KnownAlgebra (GAlgebra (Rep a))
99− , HTable (GColumnsHKD a)
100− , Eval (GGTable (GAlgebra (Rep a)) (TTable (Reify f)) TColumns (Col (Reify f)) (GRecord (GMap (TColumn (Reify f)) (Rep a))))
101− , Eval (GGColumns (GAlgebra (Rep a)) TColumns (GRecord (GMap (TColumn (Reify f)) (Rep a)))) ~ GColumnsHKD a
102− , Eval (GGContext (GAlgebra (Rep a)) TUnreifyContext (GRecord (GMap (TColumn (Reify f)) (Rep a)))) ~ f
103− , GRecordable (GMap (TColumn (Reify f)) (Rep a))
104− , GMappable (TTable (Reify f)) (GMap (TColumn (Reify f)) (Rep a))
105− , GMap TUnreify (GMap (TColumn (Reify f)) (Rep a)) ~ GMap (TColumn f) (Rep a)
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))
106119 )
107120 => Generic (HKD a f)
108121 where
109122 type Rep (HKD a f) = GMap (TColumn f) (Rep a)
110123
111124 from =
112− gmap @(TTable (Reify f)) (Proxy @TUnreify) (unreify Refl) .
113− gunrecord @(GMap (TColumn (Reify f)) (Rep a)) .
114− ggfromColumns
115− @(GAlgebra (Rep a))
116− @(TTable (Reify f))
125+ gunrecord @(GMap (TColumn f) (Rep a)) .
126+ G.gfromColumns
127+ @(TTable f)
117128 @TColumns
118− (\(Reify a) -> a)
119− Reify
120129 fromColumns .
121− hreify .
122130 (\(HKD a) -> a)
123131
124132 to =
125133 HKD .
126− hunreify .
127− ggtoColumns
128− @(GAlgebra (Rep a))
129− @(TTable (Reify f))
134+ G.gtoColumns
135+ @(TTable f)
130136 @TColumns
131− (\(Reify a) -> a)
132− Reify
133137 toColumns .
134− grecord @(GMap (TColumn (Reify f)) (Rep a)) .
135− gunmap @(TTable (Reify f)) (Proxy @TUnreify) (reify Refl)
136−
137−
138−type HKDT :: Type -> Type
139−newtype HKDT a = HKDT
140− { unHKDT :: a
141− }
142−
143−
144−instance HKDable a => Table Result (HKDT a) where
145− type Columns (HKDT a) = GColumnsHKD a
146− type Context (HKDT a) = Result
147− type Unreify (HKDT a) = Void
148−
149− fromColumns = HKDT . fromHKD . HKD
150− toColumns = (\(HKD a) -> a) . toHKD . (\(HKDT a) -> a)
151− reify = notReify
152− unreify = notReify
153−
154−
155−instance
156− ( Table Expr (HKD a Expr)
157− , Columns (HKD a Expr) ~ GColumns (HKD a)
158− , HKDable a
159− , x ~ HKD a Expr
160− )
161− => ToExprs x (HKDT a)
162− where
163− toResult = (\(HKD a) -> a) . toHKD . (\(HKDT a) -> a)
164− fromResult = HKDT . fromHKD . HKD
165−
166−
167−fromHKD :: HKDable a => HKD a Result -> a
168−fromHKD = to . gunmap @Top (Proxy @(TColumn Result)) id . from
169−
170−
171−toHKD :: HKDable a => a -> HKD a Result
172−toHKD = to . gmap @Top (Proxy @(TColumn Result)) id . from
173−
174−
175−class Top_
176−instance Top_
177−
178−
179−data Top :: Type -> Exp Constraint
180−type instance Eval (Top _) = Top_
138+ grecord @(GMap (TColumn f) (Rep a))
181139
182140
141+type HKDable :: Type -> Constraint
183142class
184− ( Generic a
143+ ( Generic (Record a)
185144 , HTable (GColumns (HKD a))
186145 , KnownAlgebra (GAlgebra (Rep a))
187− , Eval (GGTable (GAlgebra (Rep a)) (TTable (Reify Result)) TColumns (Col (Reify Result)) (GRecord (GMap (TColumn (Reify Result)) (Rep a))))
188− , Eval (GGContext (GAlgebra (Rep a)) TUnreifyContext (GRecord (GMap (TColumn (Reify Result)) (Rep a)))) ~ Result
189− , GRecordable (GMap (TColumn (Reify Result)) (Rep a))
190− , GMappable Top (Rep a)
191− , GMappable (TTable (Reify Result)) (GMap (TColumn (Reify Result)) (Rep a))
192− , GMap TUnreify (GMap (TColumn (Reify Result)) (Rep a)) ~ GMap (TColumn Result) (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)
193148 )
194149 => HKDable a
195150instance
196− ( Generic a
151+ ( Generic (Record a)
197152 , HTable (GColumns (HKD a))
198153 , KnownAlgebra (GAlgebra (Rep a))
199− , Eval (GGTable (GAlgebra (Rep a)) (TTable (Reify Result)) TColumns (Col (Reify Result)) (GRecord (GMap (TColumn (Reify Result)) (Rep a))))
200− , Eval (GGContext (GAlgebra (Rep a)) TUnreifyContext (GRecord (GMap (TColumn (Reify Result)) (Rep a)))) ~ Result
201− , GRecordable (GMap (TColumn (Reify Result)) (Rep a))
202− , GMappable Top (Rep a)
203− , GMappable (TTable (Reify Result)) (GMap (TColumn (Reify Result)) (Rep a))
204− , GMap TUnreify (GMap (TColumn (Reify Result)) (Rep a)) ~ GMap (TColumn Result) (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)
205156 )
206157 => HKDable a
207158
208159
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+
209169type BuildableHKD :: Type -> Symbol -> Constraint
210170class GGBuildable (GAlgebra (Rep a)) name (HKDRep a) => BuildableHKD a name
211171instance GGBuildable (GAlgebra (Rep a)) name (HKDRep a) => BuildableHKD a name
src/Rel8/Table/List.hs+65−55
@@ -1,3 +1,4 @@
1+{-# language DataKinds #-}
12{-# language FlexibleContexts #-}
23{-# language FlexibleInstances #-}
34{-# language MultiParamTypeClasses #-}
@@ -10,30 +11,36 @@
1011
1112module Rel8.Table.List
1213 ( ListTable(..)
13− , listTable, nameListTable
14+ , ($*)
15+ , listTable
16+ , nameListTable
1417 )
1518where
1619
1720-- base
1821import Data.Functor.Identity ( Identity( Identity ) )
1922import Data.Kind ( Type )
20−import Data.Type.Equality ( (:~:)( Refl ) )
2123import Prelude
2224
2325-- rel8
24−import Rel8.Expr ( Expr, Col( E, unE ) )
26+import Rel8.Expr ( Expr )
2527import Rel8.Expr.Array ( sappend, sempty, slistOf )
2628import Rel8.Schema.Dict ( Dict( Dict ) )
2729import Rel8.Schema.HTable.List ( HListTable )
28−import Rel8.Schema.HTable.Vectorize ( happend, hempty, hvectorize )
29−import Rel8.Schema.Name ( Col( N ), Name( Name ) )
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 ) )
3037import Rel8.Schema.Null ( Nullity( Null, NotNull ) )
31−import Rel8.Schema.Spec ( SSpec(..) )
32−import Rel8.Schema.Spec.ConstrainDBType ( dbTypeDict, dbTypeNullity )
33−import Rel8.Schema.Reify ( hreify, hunreify )
38+import Rel8.Schema.Result ( vectorizer, unvectorizer )
39+import Rel8.Schema.Spec ( Spec(..) )
3440import Rel8.Table
3541 ( Table, Context, Columns, fromColumns, toColumns
36− , reify, unreify
42+ , FromExprs, fromResult, toResult
43+ , Transpose
3744 )
3845import Rel8.Table.Alternative
3946 ( AltTable, (<|>:)
@@ -41,87 +48,90 @@ import Rel8.Table.Alternative
4148 )
4249import Rel8.Table.Eq ( EqTable, eqTable )
4350import Rel8.Table.Ord ( OrdTable, ordTable )
44−import Rel8.Table.Recontextualize ( Recontextualize )
45−import Rel8.Table.Serialize ( FromExprs, ToExprs, fromResult, toResult )
46−import Rel8.Table.Unreify ( Unreifies )
51+import Rel8.Table.Projection
52+ ( Projectable, Projecting, Projection, project, apply
53+ )
54+import Rel8.Table.Serialize ( ToExprs )
4755
4856
4957-- | A @ListTable@ value contains zero or more instances of @a@. You construct
5058-- @ListTable@s with 'Rel8.many' or 'Rel8.listAgg'.
51−type ListTable :: Type -> Type
52−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))
62+
63+
64+instance Projectable (ListTable context) where
65+ project f (ListTable a) = ListTable (hproject (apply f) a)
5366
5467
55−instance (Table context a, Unreifies context a) =>
56− Table context (ListTable a)
68+instance (Table context a, context ~ context') =>
69+ Table context' (ListTable context a)
5770 where
58− type Columns (ListTable a) = HListTable (Columns a)
59− type Context (ListTable a) = Context a
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)
6075
6176 fromColumns = ListTable
6277 toColumns (ListTable a) = a
63−
64− reify Refl (ListTable a) = ListTable (hreify a)
65− unreify Refl (ListTable a) = ListTable (hunreify a)
66−
67−
68−instance
69− ( Unreifies from a, Unreifies to b
70− , Recontextualize from to a b
71− )
72− => Recontextualize from to (ListTable a) (ListTable b)
78+ fromResult = fmap (fromResult @_ @a) . hunvectorize unvectorizer
79+ toResult = hvectorize vectorizer . fmap (toResult @_ @a)
7380
7481
75−instance EqTable a => EqTable (ListTable a) where
82+instance (EqTable a, context ~ Expr) => EqTable (ListTable context a) where
7683 eqTable =
7784 hvectorize
78− (\SSpec {} (Identity dict) -> case dbTypeDict dict of
79− Dict -> case dbTypeNullity dict of
80− Null -> Dict
81− NotNull -> Dict)
85+ (\Spec {nullity} (Identity Dict) -> case nullity of
86+ Null -> Dict
87+ NotNull -> Dict)
8288 (Identity (eqTable @a))
8389
8490
85−instance OrdTable a => OrdTable (ListTable a) where
91+instance (OrdTable a, context ~ Expr) => OrdTable (ListTable context a) where
8692 ordTable =
8793 hvectorize
88− (\SSpec {} (Identity dict) -> case dbTypeDict dict of
89− Dict -> case dbTypeNullity dict of
90− Null -> Dict
91− NotNull -> Dict)
94+ (\Spec {nullity} (Identity Dict) -> case nullity of
95+ Null -> Dict
96+ NotNull -> Dict)
9297 (Identity (ordTable @a))
9398
9499
95−type instance FromExprs (ListTable a) = [FromExprs a]
96−
100+instance (ToExprs exprs a, context ~ Expr) =>
101+ ToExprs (ListTable context exprs) [a]
97102
98−instance ToExprs exprs a => ToExprs (ListTable exprs) [a] where
99− fromResult = fmap (fromResult @exprs) . fromColumns
100− toResult = toColumns . fmap (toResult @exprs)
101103
102−
103−instance AltTable ListTable where
104+instance context ~ Expr => AltTable (ListTable context) where
104105 (<|>:) = (<>)
105106
106107
107−instance AlternativeTable ListTable where
108+instance context ~ Expr => AlternativeTable (ListTable context) where
108109 emptyTable = mempty
109110
110111
111−instance Table Expr a => Semigroup (ListTable a) where
112− ListTable as <> ListTable bs = ListTable $
113− happend (\_ _ (E a) (E b) -> E (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
114121
115122
116−instance Table Expr a => Monoid (ListTable a) where
117− mempty = ListTable $ hempty $ \_ -> E . sempty
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 $*
118128
119129
120130-- | Construct a @ListTable@ from a list of expressions.
121−listTable :: Table Expr a => [a] -> ListTable a
131+listTable :: Table Expr a => [a] -> ListTable Expr a
122132listTable =
123133 ListTable .
124− hvectorize (\SSpec {info} -> E . slistOf info . fmap unE) .
134+ hvectorize (\Spec {info} -> slistOf info) .
125135 fmap toColumns
126136
127137
@@ -131,9 +141,9 @@ listTable =
131141nameListTable
132142 :: Table Name a
133143 => a -- ^ The names of the columns of elements of the list.
134− -> ListTable a
144+ -> ListTable Name a
135145nameListTable =
136146 ListTable .
137− hvectorize (\_ (Identity (N (Name a))) -> N (Name a)) .
147+ hvectorize (\_ (Identity (Name a)) -> Name a) .
138148 pure .
139149 toColumns
src/Rel8/Table/Maybe.hs+111−120
@@ -3,7 +3,6 @@
33{-# language DerivingStrategies #-}
44{-# language FlexibleContexts #-}
55{-# language FlexibleInstances #-}
6−{-# language LambdaCase #-}
76{-# language MultiParamTypeClasses #-}
87{-# language NamedFieldPuns #-}
98{-# language ScopedTypeVariables #-}
@@ -16,39 +15,42 @@ module Rel8.Table.Maybe
1615 ( MaybeTable(..)
1716 , maybeTable, nothingTable, justTable
1817 , isNothingTable, isJustTable
18+ , fromMaybeTable
1919 , ($?)
20+ , aggregateMaybeTable
2021 , nameMaybeTable
2122 )
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
36+import Rel8.Aggregate ( Aggregate )
3037import Rel8.Expr ( Expr )
38+import Rel8.Expr.Aggregate ( groupByExpr )
3139import Rel8.Expr.Bool ( boolExpr )
3240import Rel8.Expr.Null ( isNull, isNonNull, null, nullify )
33−import Rel8.Schema.Context.Label
34− ( Labelable, HLabelable, hlabeler, hunlabeler
35− )
36−import Rel8.Schema.Context.Nullify
37− ( Nullifiable, ConstrainTag
38− , HNullifiable, HConstrainTag
39− , hencodeTag, hdecodeTag
40− , hnullifier, hunnullifier
41− )
42−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
4344import Rel8.Schema.HTable.Identity ( HIdentity(..) )
4445import Rel8.Schema.HTable.Label ( hlabel, hunlabel )
4546import Rel8.Schema.HTable.Maybe ( HMaybeTable(..) )
46−import Rel8.Schema.HTable.Nullify ( hnullify, hunnullify )
4747import Rel8.Schema.Name ( Name )
48−import Rel8.Schema.Null ( Nullify, Nullity( Null, NotNull ), Sql, nullable )
48+import Rel8.Schema.Null ( Nullity( Null, NotNull ), Sql, nullable )
49+import qualified Rel8.Schema.Null as N
4950import Rel8.Table
5051 ( Table, Columns, Context, fromColumns, toColumns
51− , reify, unreify
52+ , FromExprs, fromResult, toResult
53+ , Transpose
5254 )
5355import Rel8.Table.Alternative
5456 ( AltTable, (<|>:)
@@ -57,12 +59,12 @@ import Rel8.Table.Alternative
5759import Rel8.Table.Bool ( bool )
5860import Rel8.Table.Eq ( EqTable, eqTable )
5961import Rel8.Table.Ord ( OrdTable, ordTable )
60−import Rel8.Table.Recontextualize ( Recontextualize )
61−import Rel8.Table.Serialize ( FromExprs, ToExprs, fromResult, toResult )
62−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 )
6365import Rel8.Table.Undefined ( undefined )
6466import Rel8.Type ( DBType )
65−import Rel8.Type.Tag ( MaybeTag )
67+import Rel8.Type.Tag ( MaybeTag( IsJust ) )
6668
6769-- semigroupoids
6870import Data.Functor.Apply ( Apply, (<.>) )
@@ -77,136 +79,160 @@ import Data.Functor.Bind ( Bind, (>>-) )
7779-- entirely of nulls, you can't distinguish if you matched an all null row, or
7880-- if the match failed. For this reason @MaybeTable@ contains an extra field -
7981-- a "nullTag" - to track whether or not the outer join produced any rows.
80−type MaybeTable :: Type -> Type
81−data MaybeTable a = MaybeTable
82− { tag :: Tag "isJust" (Maybe MaybeTag)
83− , 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
8486 }
8587 deriving stock Functor
8688
8789
88−instance Apply MaybeTable where
89− 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)
9096
9197
9298-- | Has the same behavior as the @Applicative@ instance for @Maybe@. See also:
9399-- 'Rel8.traverseMaybeTable'.
94−instance Applicative MaybeTable where
100+instance context ~ Expr => Applicative (MaybeTable context) where
95101 (<*>) = (<.>)
96102 pure = justTable
97103
98104
99−instance Bind MaybeTable where
100− 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
101107 MaybeTable tag' b -> MaybeTable (tag <> tag') b
102108
103109
104−-- | Has the same behavior as the @Monad@ instance for @Maybe@. See also:
105−-- 'Rel8.bindMaybeTable'.
106−instance Monad MaybeTable where
110+-- | Has the same behavior as the @Monad@ instance for @Maybe@.
111+instance context ~ Expr => Monad (MaybeTable context) where
107112 (>>=) = (>>-)
108113
109114
110−instance AltTable MaybeTable where
111− ma@(MaybeTable tag a) <|>: MaybeTable tag' b = MaybeTable
112− { tag = (tag <> tag')
113− { expr = boolExpr (expr tag) (expr tag') condition
114− }
115− , just = bool a b condition
116− }
117− where
118− condition = isNothingTable ma
115+instance context ~ Expr => AltTable (MaybeTable context) where
116+ ma <|>: mb = bool ma mb (isNothingTable ma)
119117
120118
121−instance AlternativeTable MaybeTable where
119+instance context ~ Expr => AlternativeTable (MaybeTable context) where
122120 emptyTable = nothingTable
123121
124122
125−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
126126 ma <> mb = maybeTable mb (\a -> maybeTable ma (justTable . (a <>)) mb) ma
127127
128128
129−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
130132 mempty = nothingTable
131133
132134
133−instance
134− ( Table context a
135− , Labelable context, Nullifiable context
136− , ConstrainTag context MaybeTag
137− ) => Table context (MaybeTable a)
135+instance (Table context a, Reifiable context, context ~ context') =>
136+ Table context' (MaybeTable context a)
138137 where
139− type Columns (MaybeTable a) = HMaybeTable (Columns a)
140− type Context (MaybeTable a) = Context a
141−
142− toColumns = toColumns1 toColumns
143− fromColumns = fromColumns1 fromColumns
144− reify = fmap fmap reify
145− unreify = fmap fmap unreify
146−
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+ }
147147
148−instance
149− ( Labelable from, Nullifiable from, ConstrainTag from MaybeTag
150− , Labelable to, Nullifiable to, ConstrainTag to MaybeTag
151− , Recontextualize from to a b
152− )
153− => Recontextualize from to (MaybeTable a) (MaybeTable b)
148+ fromColumns HMaybeTable {htag, hjust} = MaybeTable
149+ { tag = unHIdentity $ hunlabel htag
150+ , just = fromColumns $ hunlabel hjust
151+ }
154152
153+ toResult ma = HMaybeTable
154+ { htag = hlabel (HIdentity (Identity (IsJust <$ ma)))
155+ , hjust = hlabel (toResult @_ @(Nullify context a) ma)
156+ }
155157
156−instance EqTable a => EqTable (MaybeTable a) where
157− eqTable = toColumns1 id (justTable (eqTable @a))
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"
158163
159164
160−instance OrdTable a => OrdTable (MaybeTable a) where
161− ordTable = toColumns1 id (justTable (ordTable @a))
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+ }
162170
163171
164−type instance FromExprs (MaybeTable a) = Maybe (FromExprs 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+ }
165177
166178
167−instance ToExprs exprs a => ToExprs (MaybeTable exprs) (Maybe a) where
168− fromResult = fmap (fromResult @exprs) . fromColumns
169− toResult = toColumns . fmap (toResult @exprs)
179+instance (ToExprs exprs a, context ~ Expr) =>
180+ ToExprs (MaybeTable context exprs) (Maybe a)
170181
171182
172183-- | Check if a @MaybeTable@ is absent of any row. Like 'Data.Maybe.isNothing'.
173−isNothingTable :: MaybeTable a -> Expr Bool
174−isNothingTable (MaybeTable tag _) = isNull (expr tag)
184+isNothingTable :: MaybeTable Expr a -> Expr Bool
185+isNothingTable (MaybeTable tag _) = isNull tag
175186
176187
177188-- | Check if a @MaybeTable@ contains a row. Like 'Data.Maybe.isJust'.
178−isJustTable :: MaybeTable a -> Expr Bool
179−isJustTable (MaybeTable tag _) = isNonNull (expr tag)
189+isJustTable :: MaybeTable Expr a -> Expr Bool
190+isJustTable (MaybeTable tag _) = isNonNull tag
180191
181192
182193-- | Perform case analysis on a 'MaybeTable'. Like 'maybe'.
183−maybeTable :: Table Expr b => b -> (a -> b) -> MaybeTable a -> b
184−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)
185196{-# INLINABLE maybeTable #-}
186197
187198
188199-- | The null table. Like 'Nothing'.
189−nothingTable :: Table Expr a => MaybeTable a
190−nothingTable = MaybeTable (fromExpr null) undefined
200+nothingTable :: Table Expr a => MaybeTable Expr a
201+nothingTable = MaybeTable null (pure undefined)
191202
192203
193204-- | Lift any table into 'MaybeTable'. Like 'Just'. Note you can also use
194205-- 'pure'.
195−justTable :: a -> MaybeTable a
196−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
197213
198214
199215-- | Project a single expression out of a 'MaybeTable'. You can think of this
200216-- operator like the '$' operator, but it also has the ability to return
201217-- @null@.
202218($?) :: forall a b. Sql DBType b
203− => (a -> Expr b) -> MaybeTable a -> Expr (Nullify b)
219+ => (a -> Expr b) -> MaybeTable Expr a -> Expr (N.Nullify b)
204220f $? ma@(MaybeTable _ a) = case nullable @b of
205− Null -> boolExpr (f a) null (isNothingTable ma)
206− 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)
207223infixl 4 $?
208224
209225
226+-- | Lift an aggregating function to operate on a 'MaybeTable'.
227+-- @nothingTable@s and @justTable@s are grouped separately.
228+aggregateMaybeTable :: ()
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+
210236-- | Construct a 'MaybeTable' in the 'Name' context. This can be useful if you
211237-- have a 'MaybeTable' that you are storing in a table and need to construct a
212238-- 'TableSchema'.
@@ -216,40 +242,5 @@ nameMaybeTable
216242 -- 'nothingTable'.
217243 -> a
218244 -- ^ Names of the columns in @a@.
219− -> MaybeTable a
220−nameMaybeTable = MaybeTable . fromName
221−
222−
223−toColumns1 ::
224− ( HTable t
225− , HConstrainTag context MaybeTag
226− , HLabelable context
227− , HNullifiable context
228− )
229− => (a -> t context)
230− -> MaybeTable a
231− -> HMaybeTable t context
232−toColumns1 f MaybeTable {tag, just} = HMaybeTable
233− { htag
234− , hjust = hlabel hlabeler $ hnullify (hnullifier tag isNonNull) $ f just
235− }
236− where
237− htag = HIdentity (hencodeTag tag)
238−
239−
240−fromColumns1 ::
241− ( HTable t
242− , HConstrainTag context MaybeTag
243− , HLabelable context
244− , HNullifiable context
245− )
246− => (t context -> a)
247− -> HMaybeTable t context
248− -> MaybeTable a
249−fromColumns1 f HMaybeTable {htag = HIdentity htag, hjust} = MaybeTable
250− { tag
251− , just = f $ runIdentity $
252− hunnullify (\a -> pure . hunnullifier a) (hunlabel hunlabeler hjust)
253− }
254− where
255− tag = hdecodeTag htag
245+ -> MaybeTable Name a
246+nameMaybeTable tag = MaybeTable tag . pure
src/Rel8/Table/Name.hs+17−22
@@ -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 )
@@ -17,20 +20,15 @@ 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−-- opaleye
24−import qualified Opaleye.Internal.HaskellDB.PrimQuery as Opaleye
25−
2627-- rel8
27−import Rel8.Expr ( Expr, Col( E ) )
28−import Rel8.Expr.Opaleye ( toPrimExpr )
29−import Rel8.Kind.Labels ( renderLabels )
3028import Rel8.Schema.HTable ( htabulate, htabulateA, hfield, hspecs )
31−import Rel8.Schema.Name ( Name( Name ), Col( N ) )
32−import Rel8.Schema.Spec ( SSpec(..) )
33−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(..) )
3432
3533
3634-- | Construct a table in the 'Name' context containing the names of all
@@ -62,23 +60,20 @@ namesFromLabelsWith :: Table Name a
6260 => (NonEmpty String -> String) -> a
6361namesFromLabelsWith f = fromColumns $ htabulate $ \field ->
6462 case hfield hspecs field of
65− SSpec {labels} -> N (Name (f (renderLabels labels)))
66−
67−
68−showExprs :: Table Expr a => a -> [(String, Opaleye.PrimExpr)]
69−showExprs as = case (namesFromLabels, toColumns as) of
70− (names, exprs) -> getConst $ htabulateA $ \field ->
71− case (hfield names field, hfield exprs field) of
72− (N (Name name), E expr) -> Const [(name, toPrimExpr expr)]
63+ Spec {labels} -> Name (f (renderLabels labels))
7364
7465
7566showLabels :: forall a. Table (Context a) a => a -> [NonEmpty String]
7667showLabels _ = getConst $
7768 htabulateA @(Columns a) $ \field -> case hfield hspecs field of
78− SSpec {labels} -> Const [renderLabels labels]
69+ Spec {labels} -> Const (pure (renderLabels labels))
7970
8071
81−showNames :: forall a. Table Name a => a -> [String]
72+showNames :: forall a. Table Name a => a -> NonEmpty String
8273showNames (toColumns -> names) = getConst $
8374 htabulateA @(Columns a) $ \field -> case hfield names field of
84− N (Name 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+66−54
@@ -1,3 +1,4 @@
1+{-# language DataKinds #-}
12{-# language FlexibleContexts #-}
23{-# language FlexibleInstances #-}
34{-# language MultiParamTypeClasses #-}
@@ -10,7 +11,9 @@
1011
1112module Rel8.Table.NonEmpty
1213 ( NonEmptyTable(..)
13− , nonEmptyTable, nameNonEmptyTable
14+ , ($+)
15+ , nonEmptyTable
16+ , nameNonEmptyTable
1417 )
1518where
1619
@@ -18,102 +21,111 @@ where
1821import Data.Functor.Identity ( Identity( Identity ) )
1922import Data.Kind ( Type )
2023import Data.List.NonEmpty ( NonEmpty )
21−import Data.Type.Equality ( (:~:)( Refl ) )
22−import Prelude
24+import Prelude hiding ( id )
2325
2426-- rel8
25−import Rel8.Expr ( Expr, Col( E, unE ) )
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 )
30−import Rel8.Schema.Name ( Col( N ), Name( Name ) )
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 ) )
3138import Rel8.Schema.Null ( Nullity( Null, NotNull ) )
32−import Rel8.Schema.Reify ( hreify, hunreify )
33−import Rel8.Schema.Spec ( SSpec(..) )
34−import Rel8.Schema.Spec.ConstrainDBType ( dbTypeDict, dbTypeNullity )
39+import Rel8.Schema.Result ( vectorizer, unvectorizer )
40+import Rel8.Schema.Spec ( Spec(..) )
3541import Rel8.Table
3642 ( Table, Context, Columns, fromColumns, toColumns
37− , reify, unreify
43+ , FromExprs, fromResult, toResult
44+ , Transpose
3845 )
3946import Rel8.Table.Alternative ( AltTable, (<|>:) )
4047import Rel8.Table.Eq ( EqTable, eqTable )
4148import Rel8.Table.Ord ( OrdTable, ordTable )
42−import Rel8.Table.Recontextualize ( Recontextualize )
43−import Rel8.Table.Serialize ( FromExprs, ToExprs, fromResult, toResult )
44−import Rel8.Table.Unreify ( Unreifies )
49+import Rel8.Table.Projection
50+ ( Projectable, Projecting, Projection, project, apply
51+ )
52+import Rel8.Table.Serialize ( ToExprs )
4553
4654
4755-- | A @NonEmptyTable@ value contains one or more instances of @a@. You
4856-- construct @NonEmptyTable@s with 'Rel8.some' or 'nonEmptyAgg'.
49−type NonEmptyTable :: Type -> Type
50−newtype NonEmptyTable a =
51− 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))
60+
61+
62+instance Projectable (NonEmptyTable context) where
63+ project f (NonEmptyTable a) = NonEmptyTable (hproject (apply f) a)
5264
5365
54−instance (Table context a, Unreifies context a) =>
55− Table context (NonEmptyTable a)
66+instance (Table context a, context ~ context') =>
67+ Table context' (NonEmptyTable context a)
5668 where
57− type Columns (NonEmptyTable a) = HNonEmptyTable (Columns a)
58− type Context (NonEmptyTable a) = Context a
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)
5974
6075 fromColumns = NonEmptyTable
6176 toColumns (NonEmptyTable a) = a
62−
63− reify Refl (NonEmptyTable a) = NonEmptyTable (hreify a)
64− unreify Refl (NonEmptyTable a) = NonEmptyTable (hunreify a)
65−
66−
67−instance
68− ( Unreifies from a, Unreifies to b
69− , Recontextualize from to a b
70− )
71− => Recontextualize from to (NonEmptyTable a) (NonEmptyTable b)
77+ fromResult = fmap (fromResult @_ @a) . hunvectorize unvectorizer
78+ toResult = hvectorize vectorizer . fmap (toResult @_ @a)
7279
7380
74−instance EqTable a => EqTable (NonEmptyTable a) where
81+instance (EqTable a, context ~ Expr) =>
82+ EqTable (NonEmptyTable context a)
83+ where
7584 eqTable =
7685 hvectorize
77− (\SSpec {} (Identity dict) -> case dbTypeDict dict of
78− Dict -> case dbTypeNullity dict of
79− Null -> Dict
80− NotNull -> Dict)
86+ (\Spec {nullity} (Identity Dict) -> case nullity of
87+ Null -> Dict
88+ NotNull -> Dict)
8189 (Identity (eqTable @a))
8290
8391
84−instance OrdTable a => OrdTable (NonEmptyTable a) where
92+instance (OrdTable a, context ~ Expr) =>
93+ OrdTable (NonEmptyTable context a)
94+ where
8595 ordTable =
8696 hvectorize
87− (\SSpec {} (Identity dict) -> case dbTypeDict dict of
88− Dict -> case dbTypeNullity dict of
89− Null -> Dict
90− NotNull -> Dict)
97+ (\Spec {nullity} (Identity Dict) -> case nullity of
98+ Null -> Dict
99+ NotNull -> Dict)
91100 (Identity (ordTable @a))
92101
93102
94−type instance FromExprs (NonEmptyTable a) = NonEmpty (FromExprs a)
95−
96−
97−instance ToExprs exprs a => ToExprs (NonEmptyTable exprs) (NonEmpty a)
98− where
99− fromResult = fmap (fromResult @exprs) . fromColumns
100− toResult = toColumns . fmap (toResult @exprs)
103+instance (ToExprs exprs a, context ~ Expr) =>
104+ ToExprs (NonEmptyTable context exprs) (NonEmpty a)
101105
102106
103−instance AltTable NonEmptyTable where
107+instance context ~ Expr => AltTable (NonEmptyTable context) where
104108 (<|>:) = (<>)
105109
106110
107−instance Table Expr a => Semigroup (NonEmptyTable a) where
111+instance (Table Expr a, context ~ Expr) => Semigroup (NonEmptyTable context a)
112+ where
108113 NonEmptyTable as <> NonEmptyTable bs = NonEmptyTable $
109− happend (\_ _ (E a) (E b) -> E (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 $+
110122
111123
112124-- | Construct a @NonEmptyTable@ from a non-empty list of expressions.
113−nonEmptyTable :: Table Expr a => NonEmpty a -> NonEmptyTable a
125+nonEmptyTable :: Table Expr a => NonEmpty a -> NonEmptyTable Expr a
114126nonEmptyTable =
115127 NonEmptyTable .
116− hvectorize (\SSpec {info} -> E . snonEmptyOf info . fmap unE) .
128+ hvectorize (\Spec {info} -> snonEmptyOf info) .
117129 fmap toColumns
118130
119131
@@ -123,9 +135,9 @@ nonEmptyTable =
123135nameNonEmptyTable
124136 :: Table Name a
125137 => a -- ^ The names of the columns of elements of the list.
126− -> NonEmptyTable a
138+ -> NonEmptyTable Name a
127139nameNonEmptyTable =
128140 NonEmptyTable .
129− hvectorize (\_ (Identity (N (Name a))) -> N (Name a)) .
141+ hvectorize (\_ (Identity (Name a)) -> Name a) .
130142 pure .
131143 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+78−64
@@ -1,136 +1,150 @@
11{-# language BlockArguments #-}
2+{-# language DataKinds #-}
23{-# language DisambiguateRecordFields #-}
34{-# language FlexibleContexts #-}
4−{-# language LambdaCase #-}
55{-# language NamedFieldPuns #-}
6+{-# language RankNTypes #-}
67{-# language TypeFamilies #-}
78{-# language ViewPatterns #-}
89
10+{-# options_ghc -Wno-deprecations #-}
11+
912module Rel8.Table.Opaleye
1013 ( aggregator
14+ , attributes
1115 , binaryspec
1216 , distinctspec
17+ , exprs
18+ , exprsWithNames
1319 , table
1420 , tableFields
1521 , unpackspec
1622 , valuesspec
23+ , view
1724 , castTable
1825 )
1926where
2027
2128-- base
22−import Prelude hiding ( undefined )
29+import Data.Functor.Const ( Const( Const ), getConst )
30+import Data.List.NonEmpty ( NonEmpty )
31+import Prelude
2332
2433-- opaleye
34+import qualified Opaleye.Adaptors as Opaleye
35+import qualified Opaleye.Field as Opaleye ( Field_ )
2536import qualified Opaleye.Internal.Aggregate as Opaleye
26−import qualified Opaleye.Internal.Binary as Opaleye
27−import qualified Opaleye.Internal.Distinct as Opaleye
2837import qualified Opaleye.Internal.HaskellDB.PrimQuery as Opaleye
29−import qualified Opaleye.Internal.PackMap as Opaleye
30−import qualified Opaleye.Internal.Unpackspec as Opaleye
3138import qualified Opaleye.Internal.Values as Opaleye
32−import qualified Opaleye.Internal.Table as Opaleye
39+import qualified Opaleye.Table as Opaleye
3340
3441-- profunctors
3542import Data.Profunctor ( dimap, lmap )
3643
3744-- rel8
38−import Rel8.Aggregate ( Col( A ), Aggregate( Aggregate ), Aggregates )
39−import Rel8.Expr ( Expr, Col(..) )
45+import Rel8.Aggregate ( Aggregate( Aggregate ), Aggregates )
46+import Rel8.Expr ( Expr )
4047import Rel8.Expr.Opaleye
4148 ( fromPrimExpr, toPrimExpr
42− , traversePrimExpr
43− , fromColumn, toColumn
44− , scastExpr
49+ , scastExpr, traverseFieldP
4550 )
46−import Rel8.Schema.HTable ( htabulateA, hfield, htraverse, hspecs, htabulate )
47−import Rel8.Schema.Name ( Col( N ), Name( Name ), Selects )
48−import Rel8.Schema.Spec ( SSpec(..) )
49−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 )
5056import Rel8.Table ( Table, fromColumns, toColumns )
51−import Rel8.Table.Undefined ( undefined )
57+import Rel8.Type.Information ( typeName )
5258
5359-- semigroupoids
5460import Data.Functor.Apply ( WrappedApplicative(..) )
61+import Data.Profunctor.Product ( ProductProfunctor )
5562
5663
5764aggregator :: Aggregates aggregates exprs => Opaleye.Aggregator aggregates exprs
58−aggregator = Opaleye.Aggregator $ Opaleye.PackMap $ \f aggregates ->
59− fmap fromColumns $ unwrapApplicative $ htabulateA $ \field ->
60− WrapApplicative $ case hfield (toColumns aggregates) field of
61− A (Aggregate (Opaleye.Aggregator (Opaleye.PackMap inner))) ->
62− E <$> inner f ()
65+aggregator = dimap toColumns fromColumns $
66+ htraverseP $
67+ lmap (\(Aggregate a) -> (a, ())) Opaleye.aggregatorApply
68+
69+
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))
6383
6484
6585binaryspec :: Table Expr a => Opaleye.Binaryspec a a
66−binaryspec = Opaleye.Binaryspec $ Opaleye.PackMap $ \f (as, bs) ->
67− fmap fromColumns $ unwrapApplicative $ htabulateA $ \field ->
68− WrapApplicative $
69− case (hfield (toColumns as) field, hfield (toColumns bs) field) of
70− (E a, E b) -> E . fromPrimExpr <$> f (toPrimExpr a, toPrimExpr b)
86+binaryspec = fromOpaleyespec Opaleye.binaryspecField
7187
7288
7389distinctspec :: Table Expr a => Opaleye.Distinctspec a a
74−distinctspec =
75− Opaleye.Distinctspec $ Opaleye.Aggregator $ Opaleye.PackMap $ \f ->
76− fmap fromColumns .
77− unwrapApplicative .
78− htraverse
79− (\(E a) ->
80− WrapApplicative $ E . fromPrimExpr <$> f (Nothing, toPrimExpr a)) .
81− toColumns
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))
82104
83105
84−table ::Selects names exprs => TableSchema names -> Opaleye.Table exprs exprs
106+table :: Selects names exprs => TableSchema names -> Opaleye.Table exprs exprs
85107table (TableSchema name schema columns) =
86108 case schema of
87− Nothing -> Opaleye.Table name (tableFields columns)
88− Just schemaName -> Opaleye.TableWithSchema schemaName name (tableFields columns)
109+ Nothing -> Opaleye.table name (tableFields columns)
110+ Just schemaName -> Opaleye.tableWithSchema schemaName name (tableFields columns)
89111
90112
91−tableFields ::Selects names exprs
113+tableFields :: Selects names exprs
92114 => names -> Opaleye.TableFields exprs exprs
93115tableFields (toColumns -> names) = dimap toColumns fromColumns $
94116 unwrapApplicative $ htabulateA $ \field -> WrapApplicative $
95117 case hfield names field of
96118 name -> lmap (`hfield` field) (go name)
97119 where
98− go :: Col Name spec -> Opaleye.TableFields (Col Expr spec) (Col Expr spec)
99− go (N (Name name)) =
100− lmap (\(E a) -> toColumn $ toPrimExpr a) $
101− E . fromPrimExpr . fromColumn <$>
102− Opaleye.requiredTableField name
120+ go :: Name a -> Opaleye.TableFields (Expr a) (Expr a)
121+ go (Name name) =
122+ traverseFieldP $
123+ Opaleye.requiredTableField name
103124
104125
105126unpackspec :: Table Expr a => Opaleye.Unpackspec a a
106−unpackspec = Opaleye.Unpackspec $ Opaleye.PackMap $ \f ->
107− fmap fromColumns .
108− unwrapApplicative .
109− htraverse (\(E a) -> WrapApplicative $ E <$> traversePrimExpr f a) .
110− toColumns
127+unpackspec = fromOpaleyespec Opaleye.unpackspecField
111128{-# INLINABLE unpackspec #-}
112129
113130
114−valuesspec :: Table Expr a => Opaleye.ValuesspecSafe a a
115−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
116135
117136
118−toPackMap :: Table Expr a
119− => a -> Opaleye.PackMap Opaleye.PrimExpr Opaleye.PrimExpr () a
120−toPackMap as = Opaleye.PackMap $ \f () ->
121− fmap fromColumns $
122− unwrapApplicative .
123− htraverse (\(E a) -> WrapApplicative $ E <$> traversePrimExpr f a) $
124− 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
125141
126142
127143-- | Transform a table by adding 'CAST' to all columns. This is most useful for
128144-- finalising a SELECT or RETURNING statement, guaranteed that the output
129145-- matches what is encoded in each columns TypeInformation.
130146castTable :: Table Expr a => a -> a
131−castTable (toColumns -> as) = fromColumns $ htabulate \i ->
132− case hfield hspecs i of
133− SSpec{info} ->
134− case hfield as i of
135− E expr ->
136− E (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+16−45
@@ -10,7 +10,6 @@
1010{-# language TypeFamilies #-}
1111{-# language TypeOperators #-}
1212{-# language UndecidableInstances #-}
13−{-# language UndecidableSuperClasses #-}
1413{-# language ViewPatterns #-}
1514
1615module Rel8.Table.Ord
@@ -25,29 +24,20 @@ import GHC.Generics ( Rep )
2524import Prelude hiding ( seq )
2625
2726-- rel8
28−import Rel8.Expr ( Expr, Col( E ) )
27+import Rel8.Expr ( Expr )
2928import Rel8.Expr.Bool ( (||.), (&&.), false, true )
3029import Rel8.Expr.Eq ( (==.) )
3130import Rel8.Expr.Ord ( (<.), (>.) )
3231import Rel8.FCF ( Eval, Exp )
3332import Rel8.Generic.Record ( Record )
34−import Rel8.Generic.Table
35− ( GGTable, GGColumns, ggtable
36− , GAlgebra
37− )
38−import Rel8.Kind.Algebra ( KnownAlgebra )
33+import Rel8.Generic.Table.Record ( GTable, GColumns, gtable )
3934import Rel8.Schema.Dict ( Dict( Dict ) )
40−import Rel8.Schema.HTable
41− ( HTable, HConstrainTable
42− , htabulateA, hfield, hdicts
43− )
44−import Rel8.Schema.HTable.Identity ( HIdentity( HType ) )
35+import Rel8.Schema.HTable ( htabulateA, hfield )
36+import Rel8.Schema.HTable.Identity ( HIdentity( HIdentity ) )
4537import Rel8.Schema.Null (Sql)
46−import Rel8.Schema.Spec.ConstrainDBType ( ConstrainDBType, nullifier )
4738import Rel8.Table ( Columns, toColumns, TColumns )
4839import Rel8.Table.Bool ( bool )
4940import Rel8.Table.Eq ( EqTable )
50−import Rel8.Type.Eq ( DBEq )
5141import Rel8.Type.Ord ( DBOrd )
5242
5343
@@ -56,22 +46,14 @@ import Rel8.Type.Ord ( DBOrd )
5646-- columns in a 'Table' have an instance of 'DBOrd'".
5747type OrdTable :: Type -> Constraint
5848class EqTable a => OrdTable a where
59− ordTable :: Columns a (Dict (ConstrainDBType DBOrd))
49+ ordTable :: Columns a (Dict (Sql DBOrd))
6050
6151 default ordTable ::
62− ( KnownAlgebra (GAlgebra (Rep (Record a)))
63− , Eval (GGTable (GAlgebra (Rep (Record a))) TOrdTable TColumns (Dict (ConstrainDBType DBOrd)) (Rep (Record a)))
64− , Columns a ~ Eval (GGColumns (GAlgebra (Rep (Record a))) TColumns (Rep (Record a)))
52+ ( GTable TOrdTable TColumns (Rep (Record a))
53+ , Columns a ~ GColumns TColumns (Rep (Record a))
6554 )
66− => Columns a (Dict (ConstrainDBType DBOrd))
67− ordTable =
68− ggtable
69− @(GAlgebra (Rep (Record a)))
70− @TOrdTable
71− @TColumns
72− @(Rep (Record a))
73− table
74− nullifier
55+ => Columns a (Dict (Sql DBOrd))
56+ ordTable = gtable @TOrdTable @TColumns @(Rep (Record a)) table
7557 where
7658 table (_ :: proxy x) = ordTable @x
7759
@@ -80,19 +62,8 @@ data TOrdTable :: Type -> Exp Constraint
8062type instance Eval (TOrdTable a) = OrdTable a
8163
8264
83−instance
84− ( HTable t
85− , f ~ Col Expr
86− , HConstrainTable t (ConstrainDBType DBEq)
87− , HConstrainTable t (ConstrainDBType DBOrd)
88− )
89− => OrdTable (t f)
90− where
91− ordTable = hdicts @(Columns (t f)) @(ConstrainDBType DBOrd)
92−
93−
9465instance Sql DBOrd a => OrdTable (Expr a) where
95− ordTable = HType Dict
66+ ordTable = HIdentity Dict
9667
9768
9869instance (OrdTable a, OrdTable b) => OrdTable (a, b)
@@ -127,7 +98,7 @@ instance
12798(toColumns -> as) <: (toColumns -> bs) =
12899 foldr @[] go false $ getConst $ htabulateA $ \field ->
129100 case (hfield as field, hfield bs field) of
130− (E a, E b) -> case hfield (ordTable @a) field of
101+ (a, b) -> case hfield (ordTable @a) field of
131102 Dict -> Const [(a <. b, a ==. b)]
132103 where
133104 go (lt, eq) a = lt ||. (eq &&. a)
@@ -140,7 +111,7 @@ infix 4 <:
140111(toColumns -> as) <=: (toColumns -> bs) =
141112 foldr @[] go true $ getConst $ htabulateA $ \field ->
142113 case (hfield as field, hfield bs field) of
143− (E a, E b) -> case hfield (ordTable @a) field of
114+ (a, b) -> case hfield (ordTable @a) field of
144115 Dict -> Const [(a <. b, a ==. b)]
145116 where
146117 go (lt, eq) a = lt ||. (eq &&. a)
@@ -153,7 +124,7 @@ infix 4 <=:
153124(toColumns -> as) >: (toColumns -> bs) =
154125 foldr @[] go false $ getConst $ htabulateA $ \field ->
155126 case (hfield as field, hfield bs field) of
156− (E a, E b) -> case hfield (ordTable @a) field of
127+ (a, b) -> case hfield (ordTable @a) field of
157128 Dict -> Const [(a >. b, a ==. b)]
158129 where
159130 go (gt, eq) a = gt ||. (eq &&. a)
@@ -166,7 +137,7 @@ infix 4 >:
166137(toColumns -> as) >=: (toColumns -> bs) =
167138 foldr @[] go true $ getConst $ htabulateA $ \field ->
168139 case (hfield as field, hfield bs field) of
169− (E a, E b) -> case hfield (ordTable @a) field of
140+ (a, b) -> case hfield (ordTable @a) field of
170141 Dict -> Const [(a >. b, a ==. b)]
171142 where
172143 go (gt, eq) a = gt ||. (eq &&. a)
@@ -175,9 +146,9 @@ infix 4 >=:
175146
176147-- | Given two 'Table's, return the table that sorts before the other.
177148least :: OrdTable a => a -> a -> a
178−least a b = bool a b (a <: b)
149+least a b = bool b a (a <: b)
179150
180151
181152-- | Given two 'Table's, return the table that sorts after the other.
182153greatest :: OrdTable a => a -> a -> a
183−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 ( unE )
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 $ unE . (`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 $ unE . (`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−-- | @Recontextualize from to a b@ is evidence that the types @a@ and @b@ are
31−-- related, and that @b@ is the same type as @a@, but after changing the
32−-- context from the initial context @from@, to the new context @to@.
33−type Recontextualize :: K.Context -> K.Context -> Type -> Type -> Constraint
34−class
35− ( Table from a
36− , Table to b
37− , Congruent a b
38− , Recontextualize from from a a
39− , Recontextualize to to b b
40− , Recontextualize to from b a
41− ) => Recontextualize from to a b
42− | a -> from
43− , b -> to
44− , a to -> b
45− , b from -> a
46−
47−
48−instance Sql DBType a => Recontextualize Result Result (Identity a) (Identity a)
49−
50−
51−instance HTable t => Recontextualize from to (t (Col from)) (t (Col to))
52−
53−
54−instance
55− ( Recontextualize from to a1 b1
56− , Recontextualize from to a2 b2
57− , Labelable from
58− , Labelable to
59− )
60− => Recontextualize from to (a1, a2) (b1, b2)
61−
62−
63−instance
64− ( Recontextualize from to a1 b1
65− , Recontextualize from to a2 b2
66− , Recontextualize from to a3 b3
67− , Labelable from, Labelable to
68− )
69− => Recontextualize from to (a1, a2, a3) (b1, b2, b3)
70−
71−
72−instance
73− ( Recontextualize from to a1 b1
74− , Recontextualize from to a2 b2
75− , Recontextualize from to a3 b3
76− , Recontextualize from to a4 b4
77− , Labelable from, Labelable to
78− )
79− => Recontextualize from to (a1, a2, a3, a4) (b1, b2, b3, b4)
80−
81−
82−instance
83− ( Recontextualize from to a1 b1
84− , Recontextualize from to a2 b2
85− , Recontextualize from to a3 b3
86− , Recontextualize from to a4 b4
87− , Recontextualize from to a5 b5
88− , Labelable from, Labelable to
89− )
90− => Recontextualize from to (a1, a2, a3, a4, a5) (b1, b2, b3, b4, b5)
src/Rel8/Table/Rel8able.hs+29−85
@@ -1,6 +1,6 @@
11{-# language DataKinds #-}
22{-# language FlexibleInstances #-}
3−{-# language FunctionalDependencies #-}
3+{-# language MultiParamTypeClasses #-}
44{-# language ScopedTypeVariables #-}
55{-# language StandaloneKindSignatures #-}
66{-# language TypeApplications #-}
@@ -15,134 +15,78 @@ module Rel8.Table.Rel8able
1515where
1616
1717-- base
18−import Data.Kind ( Constraint, Type )
19−import Data.Type.Equality ( (:~:)( Refl ) )
20−import Prelude
18+import Prelude ()
2119
2220-- rel8
2321import Rel8.Expr ( Expr )
2422import qualified Rel8.Kind.Algebra as K
25−import Rel8.Kind.Context
26− ( SContext( SReify )
27− , Reifiable, contextSing
28− , sLabelable, sReifiable
29− )
23+import Rel8.Kind.Context ( Reifiable, contextSing )
3024import Rel8.Generic.Rel8able
3125 ( Rel8able, Algebra
3226 , GColumns, gfromColumns, gtoColumns
33− , greify, gunreify
27+ , GFromExprs, gfromResult, gtoResult
3428 )
35−import Rel8.Schema.Context ( Col )
36−import Rel8.Schema.Context.Label ( Labelable )
37−import Rel8.Schema.Dict ( Dict( Dict ) )
3829import qualified Rel8.Schema.Kind as K
3930import Rel8.Schema.HTable ( HConstrainTable, hdicts )
40−import Rel8.Schema.Reify ( hreify, hunreify, UnwrapReify )
31+import Rel8.Schema.Null ( Sql )
4132import Rel8.Schema.Result ( Result )
4233import Rel8.Table
43− ( Table, Columns, Context, Congruent, fromColumns, toColumns
44− , Unreify, reify, unreify
34+ ( Table, Columns, Context, fromColumns, toColumns
35+ , FromExprs, fromResult, toResult
36+ , Transpose
4537 )
46−import Rel8.Schema.Spec.ConstrainDBType ( ConstrainDBType )
47−import Rel8.Table.ADT ( ADT( ADT ), ADTable, fromADT, toADT )
38+import Rel8.Table.ADT ( ADT )
4839import Rel8.Table.Eq ( EqTable, eqTable )
49−import Rel8.Table.HKD ( HKD )
5040import Rel8.Table.Ord ( OrdTable, ordTable )
51−import Rel8.Table.Recontextualize ( Recontextualize )
52−import Rel8.Table.Serialize ( FromExprs, ToExprs, fromResult, toResult )
41+import Rel8.Table.Serialize ( ToExprs )
5342import Rel8.Type.Eq ( DBEq )
5443import Rel8.Type.Ord ( DBOrd )
5544
5645
57−instance (Rel8able t, Labelable context, Reifiable context) =>
58− Table context (t context)
46+instance (Rel8able t, Reifiable context, context ~ context') =>
47+ Table context' (t context)
5948 where
6049 type Columns (t context) = GColumns t
6150 type Context (t context) = context
62− type Unreify (t context) = t (UnwrapReify context)
63−
64− fromColumns = gunreify . gfromColumns . hreify
65− toColumns = hunreify . gtoColumns . greify
66−
67− reify Refl = case contextSing @context of
68− SReify context -> case sLabelable context of
69− Dict -> case sReifiable context of
70− Dict -> greify
71−
72− unreify Refl = case contextSing @context of
73− SReify context -> case sLabelable context of
74− Dict -> case sReifiable context of
75− Dict -> gunreify
76−
51+ type FromExprs (t context) = GFromExprs t
52+ type Transpose to (t context) = t to
7753
78−instance
79− ( Rel8able t
80− , Labelable from, Reifiable from
81− , Labelable to, Reifiable to
82− , Congruent (t from) (t to)
83− )
84− => Recontextualize from to (t from) (t to)
54+ fromColumns = gfromColumns contextSing
55+ toColumns = gtoColumns contextSing
56+ fromResult = gfromResult @t
57+ toResult = gtoResult @t
8558
8659
8760instance
8861 ( context ~ Expr
8962 , Rel8able t
90− , HConstrainTable (Columns (t context)) (ConstrainDBType DBEq)
63+ , HConstrainTable (Columns (t context)) (Sql DBEq)
9164 )
9265 => EqTable (t context)
9366 where
94− eqTable = hdicts @(Columns (t context)) @(ConstrainDBType DBEq)
67+ eqTable = hdicts @(Columns (t context)) @(Sql DBEq)
9568
9669
9770instance
9871 ( context ~ Expr
9972 , Rel8able t
100− , HConstrainTable (Columns (t context)) (ConstrainDBType DBEq)
101− , HConstrainTable (Columns (t context)) (ConstrainDBType DBOrd)
73+ , HConstrainTable (Columns (t context)) (Sql DBEq)
74+ , HConstrainTable (Columns (t context)) (Sql DBOrd)
10275 )
10376 => OrdTable (t context)
10477 where
105− ordTable = hdicts @(Columns (t context)) @(ConstrainDBType DBOrd)
106−
107−
108−type instance FromExprs (t Expr) = FromExprs' t
78+ ordTable = hdicts @(Columns (t context)) @(Sql DBOrd)
10979
11080
11181instance
112− ( x ~ t' Expr
82+ ( Rel8able t', t' ~ Choose (Algebra t) t
83+ , x ~ t' Expr
11384 , result ~ Result
114− , ToExprs' (Algebra t) t' t
11585 )
11686 => ToExprs x (t result)
117− where
118− fromResult = fromResult' @(Algebra t) @t'
119− toResult = toResult' @(Algebra t) @t'
12087
12188
122−type FromExprs' :: K.Rel8able -> Type
123−type family FromExprs' t where
124− FromExprs' (ADT t) = t Result
125− FromExprs' (HKD a) = a
126− FromExprs' t = t Result
127−
128−
129−type ToExprs' :: K.Algebra -> K.Rel8able -> K.Rel8able -> Constraint
130−class (algebra ~ Algebra t, Rel8able t') =>
131− ToExprs' algebra t' t | algebra t -> t'
132− where
133− fromResult' :: GColumns t' (Col Result) -> t Result
134− toResult' :: t Result -> GColumns t' (Col Result)
135−
136−
137−instance (Algebra t ~ 'K.Product, Rel8able t, t ~ t') =>
138− ToExprs' 'K.Product t' t
139− where
140− fromResult' = fromColumns
141− toResult' = toColumns
142−
143−
144−instance (Algebra t ~ 'K.Sum, ADTable t, t' ~ ADT t) =>
145− ToExprs' 'K.Sum t' t
146− where
147− fromResult' = fromADT . ADT
148− toResult' = (\(ADT a) -> a) . toADT
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+22−122
@@ -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 #-}
@@ -10,41 +7,31 @@
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− , ToExprs(..), FromExprs
19− , TToExprs
13+ ( Serializable, lit, litHTable, parse
14+ , ToExprs
2015 )
2116where
2217
2318-- base
19+import Data.Functor.Identity ( Identity( Identity ) )
2420import Data.Kind ( Constraint, Type )
2521import Data.List.NonEmpty ( NonEmpty )
26−import GHC.Generics ( Generic, Rep, from, to )
2722import Prelude
2823
2924-- hasql
3025import qualified Hasql.Decoders as Hasql
3126
3227-- rel8
33−import Rel8.Expr ( Expr, Col( E ) )
28+import Rel8.Expr ( Expr )
3429import Rel8.Expr.Serialize ( slitExpr, sparseValue )
35−import Rel8.FCF ( Eval, Exp )
36−import Rel8.Generic.Record ( Record(..) )
37−import Rel8.Generic.Table
38− ( GGToExprs, GGColumns, ggfromResult, ggtoResult
39− , GAlgebra
40− )
41−import Rel8.Kind.Algebra ( KnownAlgebra )
4230import Rel8.Schema.HTable ( HTable, htabulate, htabulateA, hfield, hspecs )
43−import Rel8.Schema.HTable.Identity ( HIdentity( HType ) )
4431import Rel8.Schema.Null ( NotNull, Sql )
45−import Rel8.Schema.Result ( Col( R ), Result )
46−import Rel8.Schema.Spec ( SSpec(..), KnownSpec )
47−import Rel8.Table ( Table, Columns, fromColumns, toColumns, TColumns )
32+import Rel8.Schema.Result ( Result )
33+import Rel8.Schema.Spec ( Spec(..) )
34+import Rel8.Table ( Table, fromColumns, FromExprs, fromResult, toResult )
4835import Rel8.Type ( DBType )
4936
5037-- semigroupoids
@@ -53,71 +40,21 @@ import Data.Functor.Apply ( WrappedApplicative(..) )
5340
5441-- | @ToExprs exprs a@ is evidence that the types @exprs@ and @a@ describe
5542-- essentially the same type, but @exprs@ is in the 'Expr' context, and @a@ is
56−-- in the 'Result' context.
43+-- a normal Haskell type.
5744type ToExprs :: Type -> Type -> Constraint
58−class Table Expr exprs => ToExprs exprs a where
59− fromResult :: Columns exprs (Col Result) -> a
60− toResult :: a -> Columns exprs (Col Result)
61−
62− default fromResult ::
63− ( Generic (Record a)
64− , KnownAlgebra (GAlgebra (Rep (Record exprs)))
65− , Eval (GGToExprs (GAlgebra (Rep (Record exprs))) TToExprs TColumns (Rep (Record exprs)) (Rep (Record a)))
66− , Columns exprs ~ Eval (GGColumns (GAlgebra (Rep (Record exprs))) TColumns (Rep (Record exprs)))
67− )
68− => Columns exprs (Col Result) -> a
69− fromResult =
70− unrecord .
71− to .
72− ggfromResult
73− @(GAlgebra (Rep (Record exprs)))
74− @TToExprs
75− @TColumns
76− @(Rep (Record exprs))
77− (\(_ :: proxy expr) -> fromResult @expr)
78−
79− default toResult ::
80− ( Generic (Record a)
81− , KnownAlgebra (GAlgebra (Rep (Record exprs)))
82− , Eval (GGToExprs (GAlgebra (Rep (Record exprs))) TToExprs TColumns (Rep (Record exprs)) (Rep (Record a)))
83− , Columns exprs ~ Eval (GGColumns (GAlgebra (Rep (Record exprs))) TColumns (Rep (Record exprs)))
84− )
85− => a -> Columns exprs (Col Result)
86− toResult =
87− ggtoResult
88− @(GAlgebra (Rep (Record exprs)))
89− @TToExprs
90− @TColumns
91− @(Rep (Record exprs))
92− (\(_ :: proxy expr) -> toResult @expr) .
93− from .
94− Record
95−
96−
97−data TToExprs :: Type -> Type -> Exp Constraint
98−type instance Eval (TToExprs exprs a) = ToExprs exprs a
99−
100−
101−instance {-# OVERLAPPABLE #-} (Sql DBType a, x ~ Expr a) => ToExprs x a where
102− fromResult (HType (R a)) = a
103− toResult = HType . R
104−
105−
106−instance (Sql DBType a, x ~ [a]) => ToExprs (Expr x) [a] where
107− fromResult (HType (R a)) = a
108− toResult = HType . R
45+class Table Expr exprs => ToExprs exprs a
46+
47+
48+instance {-# OVERLAPPABLE #-} (Sql DBType a, x ~ Expr a) => ToExprs x a
49+
50+
51+instance (Sql DBType a, x ~ [a]) => ToExprs (Expr x) [a]
10952
11053
11154instance (Sql DBType a, NotNull a, x ~ Maybe a) => ToExprs (Expr x) (Maybe a)
112− where
113− fromResult (HType (R a)) = a
114− toResult = HType . R
11555
11656
11757instance (Sql DBType a, NotNull a, x ~ NonEmpty a) => ToExprs (Expr x) (NonEmpty a)
118− where
119− fromResult (HType (R a)) = a
120− toResult = HType . R
12158
12259
12360instance (ToExprs exprs1 a, ToExprs exprs2 b, x ~ (exprs1, exprs2)) =>
@@ -179,43 +116,6 @@ instance
179116 => ToExprs x (a, b, c, d, e, f, g)
180117
181118
182−instance (HTable t, result ~ Col Result, x ~ t (Col Expr)) =>
183− ToExprs x (t result)
184− where
185− fromResult = id
186− toResult = id
187−
188−
189−instance (KnownSpec spec, x ~ Col Expr spec) =>
190− ToExprs x (Col Result spec)
191− where
192− fromResult = fromColumns
193− toResult = toColumns
194−
195−
196−-- | The @FromExprs@ type function maps a type in the @Expr@ context to the
197−-- corresponding type in the @Result@ context.
198−type FromExprs :: Type -> Type
199−type family FromExprs a
200−type instance FromExprs (Expr a) = a
201−type instance FromExprs (Col Expr spec) = Col Result spec
202−type instance FromExprs (a, b) = (FromExprs a, FromExprs b)
203−type instance FromExprs (a, b, c) = (FromExprs a, FromExprs b, FromExprs c)
204−type instance FromExprs (a, b, c, d) =
205− (FromExprs a, FromExprs b, FromExprs c, FromExprs d)
206−type instance FromExprs (a, b, c, d, e) =
207− (FromExprs a, FromExprs b, FromExprs c, FromExprs d, FromExprs e)
208−type instance FromExprs (a, b, c, d, e, f) =
209− ( FromExprs a, FromExprs b, FromExprs c, FromExprs d, FromExprs e
210− , FromExprs f
211− )
212−type instance FromExprs (a, b, c, d, e, f, g) =
213− ( FromExprs a, FromExprs b, FromExprs c, FromExprs d, FromExprs e
214− , FromExprs f, FromExprs g
215− )
216−type instance FromExprs (t (Col Expr)) = t (Col Result)
217−
218−
219119-- | @Serializable@ witnesses the one-to-one correspondence between the type
220120-- @sql@, which contains SQL expressions, and the type @haskell@, which
221121-- contains the Haskell decoding of rows containing @sql@ SQL expressions.
@@ -228,21 +128,21 @@ instance {-# OVERLAPPING #-} Sql DBType a => Serializable (Expr a) a
228128-- | Use @lit@ to turn literal Haskell values into expressions. @lit@ is
229129-- capable of lifting single @Expr@s to full tables.
230130lit :: forall exprs a. Serializable exprs a => a -> exprs
231−lit = fromColumns . litHTable . toResult @exprs
131+lit = fromColumns . litHTable . toResult @_ @exprs
232132
233133
234134parse :: forall exprs a. Serializable exprs a => Hasql.Row a
235−parse = fromResult @exprs <$> parseHTable
135+parse = fromResult @_ @exprs <$> parseHTable
236136
237137
238−litHTable :: HTable t => t (Col Result) -> t (Col Expr)
138+litHTable :: HTable t => t Result -> t Expr
239139litHTable as = htabulate $ \field ->
240140 case hfield hspecs field of
241− SSpec {nullity, info} -> case hfield as field of
242− R value -> E (slitExpr nullity info value)
141+ Spec {nullity, info} -> case hfield as field of
142+ Identity value -> slitExpr nullity info value
243143
244144
245−parseHTable :: HTable t => Hasql.Row (t (Col Result))
145+parseHTable :: HTable t => Hasql.Row (t Result)
246146parseHTable = unwrapApplicative $ htabulateA $ \field ->
247147 WrapApplicative $ case hfield hspecs field of
248− SSpec {nullity, info} -> R <$> sparseValue nullity info
148+ Spec {nullity, info} -> Identity <$> 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 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+164−148
@@ -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 #-}
@@ -21,52 +20,49 @@ module Rel8.Table.These
2120 , isThisTable, isThatTable, isThoseTable
2221 , hasHereTable, hasThereTable
2322 , justHereTable, justThereTable
23+ , alignMaybeTable
24+ , aggregateTheseTable
2425 , nameTheseTable
2526 )
2627where
2728
2829-- base
29−import Control.Applicative ( liftA2 )
3030import Data.Bifunctor ( Bifunctor, bimap )
31−import Data.Functor.Identity ( runIdentity )
3231import Data.Kind ( Type )
33−import Prelude hiding ( undefined )
32+import Data.Maybe ( isJust )
33+import Prelude hiding ( null, undefined )
3434
3535-- rel8
36+import Rel8.Aggregate ( Aggregate )
3637import Rel8.Expr ( Expr )
37−import Rel8.Expr.Bool ( (&&.), not_ )
38−import Rel8.Expr.Null ( isNonNull )
39−import Rel8.Schema.Context.Label
40− ( Labelable
41− , HLabelable, hlabeler, hunlabeler
42− )
43−import Rel8.Schema.Context.Nullify
44− ( Nullifiable, ConstrainTag
45− , HNullifiable, HConstrainTag
46− , hencodeTag, hdecodeTag
47− , hnullifier, hunnullifier
48− )
49−import Rel8.Schema.HTable ( HTable )
50−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 )
5144import Rel8.Schema.HTable.Identity ( HIdentity(..) )
52−import Rel8.Schema.HTable.Nullify ( hnullify, hunnullify )
45+import Rel8.Schema.HTable.Maybe ( HMaybeTable(..) )
5346import Rel8.Schema.HTable.These ( HTheseTable(..) )
47+import qualified Rel8.Schema.Kind as K
5448import Rel8.Schema.Name ( Name )
5549import Rel8.Table
5650 ( Table, Columns, Context, fromColumns, toColumns
57− , reify, unreify
51+ , FromExprs, fromResult, toResult
52+ , Transpose
5853 )
5954import Rel8.Table.Eq ( EqTable, eqTable )
6055import Rel8.Table.Maybe
6156 ( MaybeTable(..)
6257 , maybeTable, justTable, nothingTable
6358 , isJustTable
59+ , aggregateMaybeTable
6460 , nameMaybeTable
6561 )
62+import Rel8.Table.Nullify ( Nullify, guard )
6663import Rel8.Table.Ord ( OrdTable, ordTable )
67−import Rel8.Table.Recontextualize ( Recontextualize )
68−import Rel8.Table.Serialize ( FromExprs, ToExprs, fromResult, toResult )
69−import Rel8.Table.Tag ( Tag(..) )
64+import Rel8.Table.Projection ( Biprojectable, Projectable, biproject, project )
65+import Rel8.Table.Serialize ( ToExprs )
7066import Rel8.Table.Undefined ( undefined )
7167import Rel8.Type.Tag ( MaybeTag )
7268
@@ -75,7 +71,8 @@ import Data.Functor.Apply ( Apply, (<.>) )
7571import Data.Functor.Bind ( Bind, (>>-) )
7672
7773-- these
78−import Data.These ( These )
74+import Data.These ( These( This, That, These ) )
75+import Data.These.Combinators ( justHere, justThere )
7976
8077
8178-- | @TheseTable a b@ is a Rel8 table that contains either the table @a@, the
@@ -85,32 +82,45 @@ import Data.These ( These )
8582--
8683-- @TheseTable@ is operationally the same as Haskell's 'These' type, but
8784-- adapted to work with Rel8.
88−type TheseTable :: Type -> Type -> Type
89−data TheseTable a b = TheseTable
90− { here :: MaybeTable a
91− , there :: MaybeTable b
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
9289 }
9390 deriving stock Functor
9491
9592
96−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
9798 bimap f g (TheseTable a b) = TheseTable (fmap f a) (fmap g b)
9899
99100
100−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
101108 fs <.> as = TheseTable
102109 { here = here fs <> here as
103110 , there = there fs <.> there as
104111 }
105112
106113
107−instance (Table Expr a, Semigroup a) => Applicative (TheseTable a)
114+instance (context ~ Expr, Table Expr a, Semigroup a) =>
115+ Applicative (TheseTable context a)
108116 where
109117 pure = thatTable
110118 (<*>) = (<.>)
111119
112120
113−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
114124 TheseTable here1 ma >>- f = case ma >>- f' of
115125 mtb -> TheseTable
116126 { here = maybeTable here1 ((here1 <>) . fst) mtb
@@ -121,12 +131,14 @@ instance (Table Expr a, Semigroup a) => Bind (TheseTable a) where
121131 TheseTable here2 mb -> (here2,) <$> mb
122132
123133
124−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
125137 (>>=) = (>>-)
126138
127139
128−instance (Table Expr a, Table Expr b, Semigroup a, Semigroup b) =>
129− Semigroup (TheseTable a b)
140+instance (context ~ Expr, Table Expr a, Table Expr b, Semigroup a, Semigroup b) =>
141+ Semigroup (TheseTable context a b)
130142 where
131143 a <> b = TheseTable
132144 { here = here a <> here b
@@ -136,124 +148,175 @@ instance (Table Expr a, Table Expr b, Semigroup a, Semigroup b) =>
136148
137149instance
138150 ( Table context a, Table context b
139− , Labelable context, Nullifiable context, ConstrainTag context MaybeTag
140− ) => Table context (TheseTable a b)
151+ , Reifiable context, context ~ context'
152+ )
153+ => Table context' (TheseTable context a b)
141154 where
142− type Columns (TheseTable a b) = HTheseTable (Columns a) (Columns b)
143− type Context (TheseTable a b) = Context a
144−
145− toColumns = toColumns2 toColumns toColumns
146− fromColumns = fromColumns2 fromColumns fromColumns
147− reify = liftA2 bimap reify reify
148− unreify = liftA2 bimap unreify unreify
149−
150−
151−instance
152− ( Labelable from, Nullifiable from, ConstrainTag from MaybeTag
153− , Labelable to, Nullifiable to, ConstrainTag to MaybeTag
154− , Recontextualize from to a1 b1
155− , Recontextualize from to a2 b2
156− ) =>
157− Recontextualize from to (TheseTable a1 a2) (TheseTable b1 b2)
158−
159−
160−instance (EqTable a, EqTable b) => EqTable (TheseTable a b) where
161− eqTable = toColumns2 id id (thoseTable (eqTable @a) (eqTable @b))
162−
163−
164−instance (OrdTable a, OrdTable b) => OrdTable (TheseTable a b) where
165− ordTable = toColumns2 id id (thoseTable (ordTable @a) (ordTable @b))
166−
167−
168−type instance FromExprs (TheseTable a b) = These (FromExprs a) (FromExprs 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+ }
169170
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+ }
170181
171−instance (ToExprs exprs1 a, ToExprs exprs2 b, x ~ TheseTable exprs1 exprs2) =>
172− ToExprs x (These a 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)
173219 where
174− fromResult =
175− bimap (fromResult @exprs1) (fromResult @exprs2) .
176− fromColumns
177− toResult =
178− toColumns .
179− bimap (toResult @exprs1) (toResult @exprs2)
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+ }
180226
181227
182−toHereTag :: Tag "isJust" a -> Tag "hasHere" a
183−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+ }
184237
185238
186−toThereTag :: Tag "isJust" a -> Tag "hasThere" a
187−toThereTag Tag {..} = Tag {..}
239+instance (ToExprs exprs1 a, ToExprs exprs2 b, x ~ TheseTable Expr exprs1 exprs2) =>
240+ ToExprs x (These a b)
188241
189242
190243-- | Test if a 'TheseTable' was constructed with 'thisTable'.
191244--
192245-- Corresponds to 'Data.These.Combinators.isThis'.
193−isThisTable :: TheseTable a b -> Expr Bool
246+isThisTable :: TheseTable Expr a b -> Expr Bool
194247isThisTable a = hasHereTable a &&. not_ (hasThereTable a)
195248
196249
197250-- | Test if a 'TheseTable' was constructed with 'thatTable'.
198251--
199252-- Corresponds to 'Data.These.Combinators.isThat'.
200−isThatTable :: TheseTable a b -> Expr Bool
253+isThatTable :: TheseTable Expr a b -> Expr Bool
201254isThatTable a = not_ (hasHereTable a) &&. hasThereTable a
202255
203256
204257-- | Test if a 'TheseTable' was constructed with 'thoseTable'.
205258--
206259-- Corresponds to 'Data.These.Combinators.isThese'.
207−isThoseTable :: TheseTable a b -> Expr Bool
260+isThoseTable :: TheseTable Expr a b -> Expr Bool
208261isThoseTable a = hasHereTable a &&. hasThereTable a
209262
210263
211264-- | Test if the @a@ side of @TheseTable a b@ is present.
212265--
213266-- Corresponds to 'Data.These.Combinators.hasHere'.
214−hasHereTable :: TheseTable a b -> Expr Bool
267+hasHereTable :: TheseTable Expr a b -> Expr Bool
215268hasHereTable TheseTable {here} = isJustTable here
216269
217270
218271-- | Test if the @b@ table of @TheseTable a b@ is present.
219272--
220273-- Corresponds to 'Data.These.Combinators.hasThere'.
221−hasThereTable :: TheseTable a b -> Expr Bool
274+hasThereTable :: TheseTable Expr a b -> Expr Bool
222275hasThereTable TheseTable {there} = isJustTable there
223276
224277
225278-- | Attempt to project out the @a@ table of a @TheseTable a b@.
226279--
227280-- Corresponds to 'Data.These.Combinators.justHere'.
228−justHereTable :: TheseTable a b -> MaybeTable a
281+justHereTable :: TheseTable context a b -> MaybeTable context a
229282justHereTable = here
230283
231284
232285-- | Attempt to project out the @b@ table of a @TheseTable a b@.
233286--
234287-- Corresponds to 'Data.These.Combinators.justThere'.
235−justThereTable :: TheseTable a b -> MaybeTable b
288+justThereTable :: TheseTable context a b -> MaybeTable context b
236289justThereTable = there
237290
238291
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+
239302-- | Construct a @TheseTable@. Corresponds to 'This'.
240−thisTable :: Table Expr b => a -> TheseTable a b
303+thisTable :: Table Expr b => a -> TheseTable Expr a b
241304thisTable a = TheseTable (justTable a) nothingTable
242305
243306
244307-- | Construct a @TheseTable@. Corresponds to 'That'.
245−thatTable :: Table Expr a => b -> TheseTable a b
308+thatTable :: Table Expr a => b -> TheseTable Expr a b
246309thatTable b = TheseTable nothingTable (justTable b)
247310
248311
249312-- | Construct a @TheseTable@. Corresponds to 'These'.
250−thoseTable :: a -> b -> TheseTable a b
313+thoseTable :: a -> b -> TheseTable Expr a b
251314thoseTable a b = TheseTable (justTable a) (justTable b)
252315
253316
254317-- | Pattern match on a 'TheseTable'. Corresponds to 'these'.
255318theseTable :: Table Expr c
256− => (a -> c) -> (b -> c) -> (a -> b -> c) -> TheseTable a b -> c
319+ => (a -> c) -> (b -> c) -> (a -> b -> c) -> TheseTable Expr a b -> c
257320theseTable f g h TheseTable {here, there} =
258321 maybeTable
259322 (maybeTable undefined f here)
@@ -261,6 +324,19 @@ theseTable f g h TheseTable {here, there} =
261324 there
262325
263326
327+-- | Lift a pair of aggregating functions to operate on an 'TheseTable'.
328+-- @thisTable@s, @thatTable@s and @thoseTable@s are grouped separately.
329+aggregateTheseTable :: ()
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+ }
338+
339+
264340-- | Construct a 'TheseTable' in the 'Name' context. This can be useful if you
265341-- have a 'TheseTable' that you are storing in a table and need to construct a
266342-- 'TableSchema'.
@@ -273,69 +349,9 @@ nameTheseTable :: ()
273349 -- ^ Names of the columns in the @a@ table.
274350 -> b
275351 -- ^ Names of the columns in the @b@ table.
276− -> TheseTable a b
352+ -> TheseTable Name a b
277353nameTheseTable here there a b =
278354 TheseTable
279355 { here = nameMaybeTable here a
280356 , there = nameMaybeTable there b
281357 }
282−
283−
284−toColumns2 ::
285− ( HTable t
286− , HTable u
287− , HConstrainTag context MaybeTag
288− , HLabelable context
289− , HNullifiable context
290− )
291− => (a -> t context)
292− -> (b -> u context)
293− -> TheseTable a b
294− -> HTheseTable t u context
295−toColumns2 f g TheseTable {here, there} = HTheseTable
296− { hhereTag = HIdentity $ hencodeTag (toHereTag (tag here))
297− , hhere =
298− hlabel hlabeler $ hnullify (hnullifier (tag here) isNonNull) $ f (just here)
299− , hthereTag = HIdentity $ hencodeTag (toThereTag (tag there))
300− , hthere =
301− hlabel hlabeler $ hnullify (hnullifier (tag there) isNonNull) $ g (just there)
302− }
303−
304−
305−fromColumns2 ::
306− ( HTable t
307− , HTable u
308− , HConstrainTag context MaybeTag
309− , HLabelable context
310− , HNullifiable context
311− )
312− => (t context -> a)
313− -> (u context -> b)
314− -> HTheseTable t u context
315− -> TheseTable a b
316−fromColumns2 f g HTheseTable {hhereTag, hhere, hthereTag, hthere} = TheseTable
317− { here =
318− let
319− tag = hdecodeTag $ unHIdentity hhereTag
320− in
321− MaybeTable
322− { tag
323− , just = f $
324− runIdentity $
325− hunnullify (\a -> pure . hunnullifier a) $
326− hunlabel hunlabeler
327− hhere
328− }
329− , there =
330− let
331− tag = hdecodeTag $ unHIdentity hthereTag
332− in
333− MaybeTable
334− { tag
335− , just = g $
336− runIdentity $
337− hunnullify (\a -> pure . hunnullifier a) $
338− hunlabel hunlabeler
339− hthere
340− }
341− }
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( E ) )
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 -> E (snull info)
26− NotNull -> E (unsafeUnnullify (snull info))
24+ Spec {nullity, info} -> case nullity of
25+ Null -> snull info
26+ NotNull -> unsafeUnnullify (snull info)
src/Rel8/Table/Unreify.hsdeleted−102
@@ -1,102 +0,0 @@
1−{-# language DataKinds #-}
2−{-# language FlexibleContexts #-}
3−{-# language FlexibleInstances #-}
4−{-# language GADTs #-}
5−{-# language LambdaCase #-}
6−{-# language MultiParamTypeClasses #-}
7−{-# language QuantifiedConstraints #-}
8−{-# language RankNTypes #-}
9−{-# language StandaloneKindSignatures #-}
10−{-# language TypeFamilies #-}
11−{-# language UndecidableInstances #-}
12−
13−-- | This module implements some machinery for implementing methods of the
14−-- 'Table' class for a particular special (but important) class of polymorphic
15−-- @Table@ types.
16−--
17−-- This special case is characterised by a @newtype@ wrapper around a bare
18−-- 'HTable' which is constructed by applying a type family to the polymorphic
19−-- type variable.
20−--
21−-- Examples of this class of @Table@ include @ListTable@ and @NonEmptyTable@.
22−--
23−-- The tricky part about implementing @Table@ for these types is 'reify' and
24−-- 'unreify'. There is no guarantee in general that @'Unreify' a@ is itself
25−-- a @Table@, let alone a @Table@ with the same 'Columns' as @a@
26−-- (e.g., @Unreify (AColumn Result Bool) = Bool@, and @Bool@ is not a
27−-- @Table@)
28−
29−module Rel8.Table.Unreify
30− ( Unreifiable, Unreifiability(..), unreifiability
31− , Unreifies
32− )
33−where
34−
35−-- base
36−import Data.Kind ( Constraint, Type )
37−import Prelude ()
38−
39−-- rel8
40−import Rel8.Aggregate ( Aggregate )
41−import Rel8.Expr ( Expr )
42−import Rel8.Kind.Context ( SContext(..), Reifiable, sReifiable )
43−import Rel8.Schema.Dict ( Dict( Dict ) )
44−import qualified Rel8.Schema.Kind as K
45−import Rel8.Schema.Name ( Name )
46−import Rel8.Schema.Reify ( Reify )
47−import Rel8.Schema.Result ( Result )
48−import Rel8.Table ( Table, Context, Congruent, Unreify )
49−
50−
51−type Unreifies :: K.Context -> Type -> Constraint
52−type family Unreifies context a where
53− Unreifies (Reify context) a = Unreifier context a
54− Unreifies _ _ = ()
55−
56−
57−type Unreifiable :: Type -> Constraint
58−class
59− ( Context a ~ Reify Aggregate => Unreifier Aggregate a
60− , Context a ~ Reify Expr => Unreifier Expr a
61− , Context a ~ Reify Name => Unreifier Name a
62− , (forall ctx. (Context a ~ Reify (Reify ctx), Reifiable ctx) => Unreifier (Reify ctx) a)
63− )
64− => Unreifiable a
65−instance
66− ( Context a ~ Reify Aggregate => Unreifier Aggregate a
67− , Context a ~ Reify Expr => Unreifier Expr a
68− , Context a ~ Reify Name => Unreifier Name a
69− , (forall ctx. (Context a ~ Reify (Reify ctx), Reifiable ctx) => Unreifier (Reify ctx) a)
70− )
71− => Unreifiable a
72−
73−
74−type Unreifier :: K.Context -> Type -> Constraint
75−class
76− ( Table context (Unreify a)
77− , Congruent a (Unreify a)
78− )
79− => Unreifier context a
80−instance
81− ( Table context (Unreify a)
82− , Congruent a (Unreify a)
83− )
84− => Unreifier context a
85−
86−
87−type Unreifiability :: K.Context -> Type -> Type
88−data Unreifiability context a where
89− UResult :: Unreifiability Result a
90− Unreifiability :: Unreifier context a
91− => SContext context -> Unreifiability context a
92−
93−
94−unreifiability :: (Context a ~ Reify context, Unreifiable a)
95− => SContext context -> Unreifiability context a
96−unreifiability = \case
97− SAggregate -> Unreifiability SAggregate
98− SExpr -> Unreifiability SExpr
99− SName -> Unreifiability SName
100− SResult -> UResult
101− SReify context -> case sReifiable context of
102− Dict -> Unreifiability (SReify context)
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.hsnew file+640
@@ -0,0 +1,640 @@
1+{-# language FlexibleContexts #-}
2+{-# language MonoLocalBinds #-}
3+{-# language ScopedTypeVariables #-}
4+{-# language StandaloneKindSignatures #-}
5+{-# language TypeApplications #-}
6+{-# 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').
11+
12+module Rel8.Tabulate
13+ (
14+ Tabulation
15+
16+ -- * Interfacing with 'Query's
17+ , fromQuery
18+ , toQuery
19+ , liftQuery
20+ , through
21+ , lookup
22+
23+ -- * Aggregation and Ordering
24+ , aggregate
25+ , distinct
26+ , order
27+
28+ -- ** Magic 'Tabulation's
29+ -- $magic
30+ , count
31+ , optional
32+ , many
33+ , some
34+ , exists
35+ , present
36+ , absent
37+
38+ -- * Natural joins
39+ , align
40+ , alignWith
41+ , leftAlign
42+ , leftAlignWith
43+ , rightAlign
44+ , rightAlignWith
45+ , zip
46+ , zipWith
47+ , similarity
48+ , difference
49+ )
50+where
51+
52+-- base
53+import Control.Applicative ( (<|>), empty, liftA2 )
54+import Control.Monad ( liftM2 )
55+import Data.Bifunctor ( Bifunctor, bimap, first, second )
56+import Data.Foldable ( traverse_ )
57+import Data.Function ( on )
58+import Data.Functor.Contravariant ( Contravariant, (>$<), 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
83+
84+-- rel8
85+import Rel8.Aggregate ( Aggregates )
86+import Rel8.Expr ( Expr )
87+import Rel8.Expr.Aggregate ( countStar )
88+import Rel8.Expr.Bool ( true )
89+import Rel8.Order ( Order( Order ) )
90+import Rel8.Query ( Query )
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 )
97+import Rel8.Query.These ( alignBy )
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 )
118+
119+-- semigroupoids
120+import Data.Functor.Apply ( Apply, liftF2 )
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)
167+
168+
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'.
174+--
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
201+
202+
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 (<*>))@
209+instance EqTable k => Apply (Tabulation k) where
210+ liftF2 = liftA2
211+
212+
213+-- | @pure = 'liftQuery' . pure@
214+instance EqTable k => Applicative (Tabulation k) where
215+ pure = liftQuery . pure
216+ liftA2 = liftM2
217+
218+
219+instance EqTable k => Bind (Tabulation k) where
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)
228+
229+
230+instance EqTable k => Monad (Tabulation k) where
231+ (>>=) = (>>-)
232+
233+
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
260+
261+
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.
268+--
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+-- @
282+--
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.
288+--
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'.
310+--
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`
320+
321+
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)
330+
331+
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
345+
346+
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
354+
355+
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))
365+
366+
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).
403+
404+
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, ())
482+
483+
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, ())
494+
495+
496+-- | Performs a @NATURAL FULL OUTER JOIN@ based on the common key columns.
497+--
498+-- Analogous to 'Data.Semialign.align'.
499+align :: EqTable k
500+ => Tabulation k a -> Tabulation k b -> Tabulation k (TheseTable Expr a b)
501+align = alignWith id
502+
503+
504+-- | Performs a @NATURAL FULL OUTER JOIN@ based on the common key columns.
505+--
506+-- Analogous to 'Data.Semialign.alignWith'.
507+alignWith :: EqTable k
508+ => (TheseTable Expr a b -> c)
509+ -> Tabulation k a -> Tabulation k b -> Tabulation k c
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.
535+leftAlign :: EqTable k
536+ => Tabulation k a -> Tabulation k b -> Tabulation k (a, MaybeTable Expr b)
537+leftAlign = leftAlignWith (,)
538+
539+
540+-- | Performs a @NATURAL LEFT OUTER JOIN@ based on the common key columns.
541+--
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.
548+leftAlignWith :: EqTable k
549+ => (a -> MaybeTable Expr b -> c)
550+ -> Tabulation k a -> Tabulation k b -> Tabulation k c
551+leftAlignWith f left right = liftA2 f left (optional right)
552+
553+
554+-- | Performs a @NATURAL RIGHT OUTER JOIN@ based on the common key columns.
555+--
556+-- Analogous to 'Data.Semialign.lpadZip'.
557+--
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.
568+--
569+-- Analogous to 'Data.Semialign.lpadZipWith'.
570+--
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.
582+--
583+-- Analagous to 'Data.Semialign.zip'.
584+--
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.
588+zip :: EqTable k
589+ => Tabulation k a -> Tabulation k b -> Tabulation k (a, b)
590+zip = zipWith (,)
591+
592+
593+-- | Performs a @NATURAL INNER JOIN@ based on the common key columns.
594+--
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.
600+zipWith :: EqTable k
601+ => (a -> b -> c) -> Tabulation k a -> Tabulation k b -> Tabulation k c
602+zipWith = liftA2
603+
604+
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.
607+--
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.
610+--
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.
615+similarity :: EqTable k => Tabulation k a -> Tabulation k b -> Tabulation k a
616+similarity a b = a <* present b
617+
618+
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.
624+--
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.
629+difference :: EqTable k => Tabulation k a -> Tabulation k b -> Tabulation k a
630+difference a b = a <* absent b
631+
632+
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/Composite.hs+20−19
@@ -20,6 +20,7 @@ where
2020
2121-- base
2222import Data.Functor.Const ( Const( Const ), getConst )
23+import Data.Functor.Identity ( Identity( Identity ) )
2324import Data.Kind ( Constraint, Type )
2425import Prelude
2526
@@ -30,19 +31,19 @@ import qualified Hasql.Decoders as Hasql
3031import qualified Opaleye.Internal.HaskellDB.PrimQuery as Opaleye
3132
3233-- rel8
33−import Rel8.Expr ( Col( E ), Expr )
34+import Rel8.Expr ( Expr )
3435import Rel8.Expr.Opaleye ( castExpr, fromPrimExpr, toPrimExpr )
35−import Rel8.Schema.HTable ( hfield, hspecs, htabulate, htabulateA )
36−import Rel8.Schema.Name ( Col( N ), Name( Name ) )
36+import Rel8.Schema.HTable ( HTable, hfield, hspecs, htabulate, htabulateA )
37+import Rel8.Schema.Name ( Name( Name ) )
3738import Rel8.Schema.Null ( Nullity( Null, NotNull ) )
38−import Rel8.Schema.Result ( Col( R ), Result )
39−import Rel8.Schema.Spec ( SSpec( SSpec, nullity, info ) )
40−import Rel8.Table ( Table, fromColumns, toColumns )
39+import Rel8.Schema.Result ( Result )
40+import Rel8.Schema.Spec ( Spec( Spec, nullity, info ) )
41+import Rel8.Table ( fromColumns, toColumns, fromResult, toResult )
4142import Rel8.Table.Eq ( EqTable )
42−import Rel8.Table.HKD ( HKD, HKDable, fromHKD, toHKD )
43+import Rel8.Table.HKD ( HKD, HKDable )
4344import Rel8.Table.Ord ( OrdTable )
4445import Rel8.Table.Rel8able ()
45−import Rel8.Table.Serialize ( lit )
46+import Rel8.Table.Serialize ( litHTable )
4647import Rel8.Type ( DBType, typeInformation )
4748import Rel8.Type.Eq ( DBEq )
4849import Rel8.Type.Information ( TypeInformation(..) )
@@ -67,8 +68,8 @@ newtype Composite a = Composite
6768
6869instance DBComposite a => DBType (Composite a) where
6970 typeInformation = TypeInformation
70− { decode = Hasql.composite (Composite . fromHKD <$> decoder)
71− , encode = encoder . lit . toColumns . toHKD . unComposite
71+ { decode = Hasql.composite (Composite . fromResult @_ @(HKD a Expr) <$> decoder)
72+ , encode = encoder . litHTable . toResult @_ @(HKD a Expr) . unComposite
7273 , typeName = compositeTypeName @a
7374 }
7475
@@ -103,7 +104,7 @@ class (DBType a, HKDable a) => DBComposite a where
103104-- single column expression, by combining them into a PostgreSQL composite
104105-- type.
105106compose :: DBComposite a => HKD a Expr -> Expr a
106−compose = castExpr . fromPrimExpr . encoder
107+compose = castExpr . fromPrimExpr . encoder . toColumns
107108
108109
109110-- | Expand a composite type into a 'HKD'.
@@ -112,23 +113,23 @@ compose = castExpr . fromPrimExpr . encoder
112113decompose :: forall a. DBComposite a => Expr a -> HKD a Expr
113114decompose (toPrimExpr -> a) = fromColumns $ htabulate \field ->
114115 case hfield names field of
115− N (Name name) -> case hfield hspecs field of
116− SSpec {} -> E $ fromPrimExpr $ Opaleye.CompositeExpr a name
116+ Name name -> case hfield hspecs field of
117+ Spec {} -> fromPrimExpr $ Opaleye.CompositeExpr a name
117118 where
118119 names = toColumns (compositeFields @a)
119120
120121
121−decoder :: Table Result a => Hasql.Composite a
122−decoder = fmap fromColumns $ unwrapApplicative $ htabulateA \field ->
122+decoder :: HTable t => Hasql.Composite (t Result)
123+decoder = unwrapApplicative $ htabulateA \field ->
123124 case hfield hspecs field of
124− SSpec {nullity, info} -> WrapApplicative $ R <$>
125+ Spec {nullity, info} -> WrapApplicative $ Identity <$>
125126 case nullity of
126127 Null -> Hasql.field $ Hasql.nullable $ decode info
127128 NotNull -> Hasql.field $ Hasql.nonNullable $ decode info
128129
129130
130−encoder :: Table Expr a => a -> Opaleye.PrimExpr
131−encoder (toColumns -> a) = Opaleye.FunExpr "ROW" exprs
131+encoder :: HTable t => t Expr -> Opaleye.PrimExpr
132+encoder a = Opaleye.FunExpr "ROW" exprs
132133 where
133134 exprs = getConst $ htabulateA \field -> case hfield a field of
134− E (toPrimExpr -> expr) -> Const [expr]
135+ expr -> Const [toPrimExpr expr]
src/Rel8/Type/Enum.hs+1
@@ -106,6 +106,7 @@ class (DBType a, Enumable a) => DBEnum a where
106106
107107-- | Types that are sum types, where each constructor is unary (that is, has no
108108-- fields).
109+type Enumable :: Type -> Constraint
109110class (Generic a, GEnumable (Rep a)) => Enumable a
110111instance (Generic a, GEnumable (Rep a)) => Enumable a
111112
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/Num.hs+4−1
@@ -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 )
@@ -39,13 +40,14 @@ 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
@@ -53,6 +55,7 @@ instance DBFractional Scientific
5355
5456
5557-- | The class of database types that support the @/@ operator.
58+type DBFloating :: Type -> Constraint
5659class DBFractional a => DBFloating a
5760instance DBFloating Float
5861instance 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/Tag.hs+2−1
@@ -21,7 +21,7 @@ import Prelude
2121import qualified Opaleye.Internal.HaskellDB.PrimQuery as Opaleye
2222
2323-- rel8
24−import {-# SOURCE #-} Rel8.Expr ( Expr )
24+import Rel8.Expr ( Expr )
2525import Rel8.Expr.Eq ( (==.) )
2626import Rel8.Expr.Opaleye ( zipPrimExprsWith )
2727import Rel8.Expr.Serialize ( litExpr )
@@ -90,6 +90,7 @@ instance DBMonoid MaybeTag where
9090 memptyExpr = litExpr mempty
9191
9292
93+type Tag :: Type
9394newtype Tag = Tag Text
9495 deriving newtype
9596 ( Eq, Ord, Read, Show
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+320−161
@@ -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.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
@@ -525,15 +551,38 @@ 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
@@ -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.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.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
@@ -693,16 +804,22 @@ 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 do
698− Rel8.many $ 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
702− selected' <- liftIO $ Rel8.select connection $ Rel8.catListTable =<< do
703− Rel8.many $ Rel8.values (map Rel8.lit rows)
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)
704821
705− selected' === rows
822+ selected' === liftA2 (,) rows rows
706823
707824
708825data NestedMaybeTable f = NestedMaybeTable
@@ -722,9 +839,51 @@ testNestedMaybeTable :: IO TmpPostgres.DB -> TestTree
722839testNestedMaybeTable = databasePropertyTest "Can nest MaybeTable within other tables" \transaction -> do
723840 let example = NestedMaybeTable { nmt1 = True, nmt2 = Just (TestTable "Hi" True) }
724841
725− transaction \connection -> do
726− selected <- liftIO $ Rel8.select connection do
727− x <- Rel8.values [Rel8.lit example]
728− 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)
729847
730848 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/Generic/Rel8able/Test.hs → tests/Rel8/Generic/Rel8able/Test.hsrenamed+47−16
@@ -1,11 +1,11 @@
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 #-}
1010{-# language UndecidableInstances #-}
1111
@@ -98,30 +98,20 @@ data S3Object = S3Object
9898 deriving stock Generic
9999
100100
101−deriving via HKDT S3Object
102− instance Table Result S3Object
103−
104−
105−deriving via HKDT S3Object
106− instance x ~ HKD S3Object Expr => ToExprs x S3Object
101+instance x ~ HKD S3Object Expr => ToExprs x S3Object
107102
108103
109104data HKDSum = HKDSumA Text | HKDSumB Bool Char | HKDSumC
110105 deriving stock Generic
111106
112107
113−deriving via HKDT HKDSum
114− instance Table Result HKDSum
115−
116−
117−deriving via HKDT HKDSum
118− instance x ~ HKD HKDSum Expr => ToExprs x HKDSum
108+instance x ~ HKD HKDSum Expr => ToExprs x HKDSum
119109
120110
121111data HKDTest f = HKDTest
122112 { s3Object :: Lift f S3Object
123113 , hkdSum :: Lift f HKDSum
124− }
114+ }
125115 deriving stock Generic
126116 deriving anyclass Rel8able
127117
@@ -148,10 +138,51 @@ data TableSum f
148138 deriving stock Generic
149139
150140
141+data BarbieSum f
142+ = BarbieSumA (f Bool) (f Text)
143+ | BarbieSumB
144+ | BarbieSumC (f Text)
145+ deriving stock Generic
146+
147+
151148data TableProduct f = TableProduct
152− { sum :: HADT f TableSum
149+ { sum :: HADT f BarbieSum
153150 , list :: TableList f
154151 , foos :: HList f (HADT f TableSum, Lift f HKDSum, HKDTest f)
155152 }
156153 deriving stock Generic
157154 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