- Closes#2188.
This pr introduces a new syntactical statement for defining aliases:
```
syntax alias newName := oldName;
```
where `oldName` can be any name in the expression namespace. Fixity and
module aliases are not supported at the moment.
- The `newName` does not inherit the fixity of `oldName`. We have agreed
that the goal is to inherit the fixity of `oldName` except if `newName`
has a fixity statement, but this will be done in a separate pr as it
requires #2310.
Avoid excessive backtracking in iterator and named arguments parsing.
This also improves error messages by committing to a parsing branch as
early as possible.
Stack LTS 21.6 uses GHC 9.4.5, binaries for HLS are available via ghcup.
Changes required:
1. Fix warnings about type level `:` and `[]` used without backticks.
2. Fix warnings about deprecation of builtin `~` - replaced with `import
Data.Type.Equality ( type (~) )` in the Prelude
3. SemVer is no longer a monoid
4. `path-io` now contains the `AnyPath` instances we were defining
(thanks to Jan) so they can be removed.
5. Added `aeson-better-errors-0.9.1.1` as an extra-dep. The reason it is
not part of the resolver is only because it has a strict bound on base
which is not compatible with ghc 9.4.5. To work around this I've set:
```
allow-newer: true
allow-newer-deps:
- aeson-better-errors
```
which relaxed the upper constraint bounds for `aeson-better-errors`
only. When the base constraints have been updated we can remove this
workaround.
6. Use stack2cabal to generate the cabal.project file and to freeze
dependency versions.
https://www.stackage.org/lts-21.6/cabal.config now contains the
constraint `haskeline installed`, which means that the version of
haskeline that is globally installed with GHC 9.4.5 will be used, see:
* https://github.com/commercialhaskell/stackage/issues/7002
GHC 9.4.5 comes with haskeline 0.8.2 preinstalled but our configuration
contains the source-repository-package for haskeline 0.8.2.1 (required
because we're using a fork) so if you try to run` cabal build` you get a
conflict.
Constraints from cabal imports cannot yet be overridden so it's not
possible to get rid of this conflict using the import method. So we need
to use stack2cabal with an explicit freeze file instead.
7. Remove `runTempFilePure` as this is unused and depends on
`Polysemy.Fresh` in `polysemy-zoo` which is not available in the
resolver. It turns out that it's not possible to use the `Fresh` effect
in a pure context anyway, so it was not possible to use
`runTempFilePure` for its original purpose.
8. We now use https://github.com/benz0li/ghc-musl as the base container
for static linux builds, this means we don't need to maintain our own
Docker container for this purpose.
9. The PR for the nightly builds is ready
https://github.com/anoma/juvix-nightly-builds/pull/2, it should be
merged as soon as this PR is merged.
Thanks to @benz0li for maintaining https://github.com/benz0li/ghc-musl
and (along with @TravisCardwell) for help with building the static
binary.
* Closes https://github.com/anoma/juvix/issues/2166
This PR fixes an issue with formatting ADT definitions.
Previously the pretty printer would remove required parentheses from
aggregate constructor arguments: `type t (A : Type) := c A (t A) ` ->
`type t (A : Type) := c A t A`.
We now handle this in the same way as patterns.
* https://github.com/anoma/juvix/issues/2277
- Closes#2269
Example:
```
type Sum (A B : Type) :=
| inj1 {
fst : A;
snd : B
}
| inj2 {
fst : A;
snd2 : B
};
sumSwap {A B : Type} : Sum A B -> Sum B A
| inj1@{fst; snd := y} := inj2 y fst
| inj2@{snd2 := y; fst := fst} := inj1 y fst;
```
- Closes#1642.
This pr introduces syntax for convenient record updates.
Example:
```
type Triple (A B C : Type) :=
| mkTriple {
fst : A;
snd : B;
thd : C;
};
main : Triple Nat Nat Nat;
main :=
let
p : Triple Nat Nat Nat := mkTriple 2 2 2;
p' :
Triple Nat Nat Nat :=
p @Triple{
fst := fst + 1;
snd := snd * 3
};
f : Triple Nat Nat Nat -> Triple Nat Nat Nat := (@Triple{fst := fst * 10});
in f p';
```
We write `@InductiveType{..}` to update the contents of a record. The
`@` is used for parsing. The `InductiveType` symbol indicates the type
of the record update. Inside the braces we have a list of `fieldName :=
newValue` items separated by semicolon. The `fieldName` is bound in
`newValue` with the old value of the field. Thus, we can write something
like `p @Triple{fst := fst + 1;}`.
Record updates `X@{..}` are parsed as postfix operators with higher
priority than application, so `f x y @X{q := 1}` is equivalent to `f x
(y @X{q := 1})`.
It is possible the use a record update with no argument by wrapping the
update in parentheses. See `f` in the above example.
- merge #2260 first
Allows constructors to be defined using Haskell-like Adt syntax.
E.g.
```
module Adt;
type Bool :=
| true
| false;
type Pair (A B : Type) :=
| mkPair A B;
type Nat :=
| zero
| suc Nat;
```
---------
Co-authored-by: Paul Cadman <git@paulcadman.dev>
- Closes#2258
# Overview
When we define a type with a single constructor and one ore more fields,
a local module is generated with the same name as the inductive type.
This module contains a projection for every field. Projections can be
used as any other function.
E.g. If we have
```
type Pair (A B : Type) := mkPair {
fst : A;
snd : B;
};
```
Then we generate
```
module Pair;
fst {A B : Type} : Pair A B -> A
| (mkPair a b) := a;
snd : {A B : Type} : Pair A B -> B
| (mkPair a b) := b;
end;
```
- Closes#1641
This pr adds the option to declare constructors with fields. E.g.
```
type Pair (A B : Type) :=
| mkPair {
fst : A;
snd : B
};
```
Which is desugared to
```
type Pair (A B : Type) :=
| mkPair : (fst : A) -> (snd : B) -> Pair A B;
```
making it possible to write ` mkPair (fst := 1; snd := 2)`.
Mutli-constructor types are also allowed to have fields.
- closes#1991
This pr implements named arguments as described in #1991. It does not
yet implement optional arguments, which should be added in a later pr as
they are not required for record syntax.
# Syntax Overview
Named arguments are a convenient mehcanism to provide arguments, where
we give the arguments by name instead of by position. Anything with a
type signature can have named arguments, i.e. functions, types,
constructors and axioms.
For instance, if we have (note that named arguments can also appear on
the rhs of the `:`):
```
fun : {A B : Type} (f : A -> B) : (x : A) -> B := ... ;
```
With the traditional positional application, we would write
```
fun suc zero
```
With named arguments we can write the following:
1. `fun (f := suc) (x := zero)`.
2. We can change the order: `fun (x := zero) (f := suc)`.
3. We can group the arguments: `fun (x := zero; f := suc)`.
4. We can partially apply functions with named arguments: `fun (f :=
suc) zero`.
5. We can provide implicit arguments analogously (with braces): `fun {A
:= Nat; B := Nat} (f := suc; x := zero)`.
6. We can skip implicit arguments: `fun {B := Nat} (f := suc; x :=
zero)`.
What we cannot do:
1. Skip explicit arguments. E.g. `fun (x := zero)`.
2. Mix explicit and implicit arguments in the same group. E.g. `fun (A
:= Nat; f := suc)`
3. Provide explicit and implicit arguments in different order. E.g. `fun
(f := suc; x := zero) {A := Nat}`.
GEB 0.3.2 introduces the following changes.
* The STLC frontend no longer requires full type information in terms.
The syntax of the terms changed.
* An error node has been introduced which allows to compile Juvix `fail`
nodes.
The following features required for compilation from Juvix are still
missing in GEB.
* Modular arithmetic types ([GEB issue
#61](https://github.com/anoma/geb/issues/61)).
* Functor/algebra iteration to implement bounded inductive types ([GEB
issue #62](https://github.com/anoma/geb/issues/62)).
- Closes#2060
- Closes#2189
- This pr adds support for the syntax described in #2189. It does not
drop support for the old syntax.
It is possible to automatically translate juvix files to the new syntax
by using the formatter with the `--new-function-syntax` flag. E.g.
```
juvix format --in-place --new-function-syntax
```
# Syntax changes
Type signatures follow this pattern:
```
f (a1 : Expr) .. (an : Expr) : Expr
```
where each `ai` is a non-empty list of symbols. Braces are used instead
of parentheses when the argument is implicit.
Then, we have these variants:
1. Simple body. After the signature we have `:= Expr;`.
2. Clauses. The function signature is followed by a non-empty sequence
of clauses. Each clause has the form:
```
| atomPat .. atomPat := Expr
```
# Mutual recursion
Now identifiers **do not need to be defined before they are used**,
making it possible to define mutually recursive functions/types without
any special syntax.
There are some exceptions to this. We cannot forward reference a symbol
`f` in some statement `s` if between `s` and the definition of `f` there
is one of the following statements:
1. Local module
2. Import statement
3. Open statement
I think it should be possible to drop the restriction for local modules
and import statements
- Depends on #2219
- Closes#1643
This pr introduces a `list` as a new builtin so that we can use syntax
sugar both in expressions and patterns. E.g. it is now possible to write
`[1; 2; 3;]`.
* Fixes the indices in `inline` and `specialize` for local lambda-lifted
identifiers.
* Adds the `specialize-by` pragma which allows to specialize a local
function by some of its free variables, or specialize arguments by name.
For example:
```
funa : {A : Type} -> (A -> A) -> A -> A;
funa {A} f a :=
let
{-# specialize-by: [f] #-}
go : Nat -> A;
go zero := a;
go (suc n) := f (go n);
in go 10;
```
If `funa` is inlined, then `go` will be specialized by the actual
argument substituted for `f`.
* Closes#2147
Adds a `specialize` pragma which allows to specify (explicit) arguments
considered for specialization. Whenever a function is applied to a
constant known value for the specialized argument, a new version of the
function will be created with the argument pasted in. For example, the
code
```juvix
{-# specialize: [1] #-}
mymap : {A B : Type} -> (A -> B) -> List A -> List B;
mymap f nil := nil;
mymap f (x :: xs) := f x :: mymap f xs;
main : Nat;
main := length (mymap λ{x := x + 3} (1 :: 2 :: 3 :: 4 :: nil));
```
will be transformed into code equivalent to
```juvix
mymap' : (Nat -> Nat) -> List Nat -> List Nat;
mymap' f nil := nil;
mymap' f (x :: xs) := λ{x := x + 3} x :: mymap' xs;
main : Nat;
main := length (mymap' (1 :: 2 :: 3 :: 4 :: nil));
```
* Closes#2226
For the program
```juvix
module letrec;
import Stdlib.Prelude open;
myfun : {A : Type} -> (A -> A) -> A -> A;
myfun {A} f a :=
let
go : Nat -> A -> A;
go' : Nat -> A -> A;
go zero a := a;
go (suc n) a := f (go' n a);
go' zero a := a;
go' (suc n) a := f (go n a);
in
go 5 a;
main : Nat;
main := myfun ((+) 1) 7;
```
after translating to Core and lambda-lifting we got the incorrect
indices in types of the let-bindings.
```
def myfun : Π A : Type, (A$0 → A$1) → A$1 → A$2 :=
λ(A : Type)
λ(f : A$0 → A$1)
λ(a : A$1)
let go' : Int → a$1 → a$2 := go'_9 A$2 f$1 in
let go : Int → a$2 → a$3 := go_10 A$3 f$2 in
go$0 5 a$2;
```
The indices have been corrected in this PR.
This PR prepares the 0.4.1 release.
* Bump version in package.yaml
* Update version smoke test
* Updates CHANGELOG
NB: The links in the changelog will not work until we create the release
tag.
