Commit 67465497 authored by eir@cis.upenn.edu's avatar eir@cis.upenn.edu

Add kind equalities to GHC.

This implements the ideas originally put forward in
"System FC with Explicit Kind Equality" (ICFP'13).

There are several noteworthy changes with this patch:
 * We now have casts in types. These change the kind
   of a type. See new constructor `CastTy`.

 * All types and all constructors can be promoted.
   This includes GADT constructors. GADT pattern matches
   take place in type family equations. In Core,
   types can now be applied to coercions via the
   `CoercionTy` constructor.

 * Coercions can now be heterogeneous, relating types
   of different kinds. A coercion proving `t1 :: k1 ~ t2 :: k2`
   proves both that `t1` and `t2` are the same and also that
   `k1` and `k2` are the same.

 * The `Coercion` type has been significantly enhanced.
   The documentation in `docs/core-spec/core-spec.pdf` reflects
   the new reality.

 * The type of `*` is now `*`. No more `BOX`.

 * Users can write explicit kind variables in their code,
   anywhere they can write type variables. For backward compatibility,
   automatic inference of kind-variable binding is still permitted.

 * The new extension `TypeInType` turns on the new user-facing
   features.

 * Type families and synonyms are now promoted to kinds. This causes
   trouble with parsing `*`, leading to the somewhat awkward new
   `HsAppsTy` constructor for `HsType`. This is dispatched with in
   the renamer, where the kind `*` can be told apart from a
   type-level multiplication operator. Without `-XTypeInType` the
   old behavior persists. With `-XTypeInType`, you need to import
   `Data.Kind` to get `*`, also known as `Type`.

 * The kind-checking algorithms in TcHsType have been significantly
   rewritten to allow for enhanced kinds.

 * The new features are still quite experimental and may be in flux.

 * TODO: Several open tickets: #11195, #11196, #11197, #11198, #11203.

 * TODO: Update user manual.

Tickets addressed: #9017, #9173, #7961, #10524, #8566, #11142.
Updates Haddock submodule.
parent 6e56ac58

Too many changes to show.

To preserve performance only 192 of 192+ files are displayed.
[submodule "libraries/binary"] [submodule "libraries/binary"]
path = libraries/binary path = libraries/binary
url = ../packages/binary.git url = http://git.haskell.org/packages/binary.git
ignore = untracked ignore = untracked
[submodule "libraries/bytestring"] [submodule "libraries/bytestring"]
path = libraries/bytestring path = libraries/bytestring
url = ../packages/bytestring.git url = http://git.haskell.org/packages/bytestring.git
ignore = untracked ignore = untracked
[submodule "libraries/Cabal"] [submodule "libraries/Cabal"]
path = libraries/Cabal path = libraries/Cabal
url = ../packages/Cabal.git url = http://git.haskell.org/packages/Cabal.git
ignore = untracked ignore = untracked
[submodule "libraries/containers"] [submodule "libraries/containers"]
path = libraries/containers path = libraries/containers
url = ../packages/containers.git url = http://git.haskell.org/packages/containers.git
ignore = untracked ignore = untracked
[submodule "libraries/haskeline"] [submodule "libraries/haskeline"]
path = libraries/haskeline path = libraries/haskeline
url = ../packages/haskeline.git url = http://git.haskell.org/packages/haskeline.git
ignore = untracked ignore = untracked
[submodule "libraries/pretty"] [submodule "libraries/pretty"]
path = libraries/pretty path = libraries/pretty
url = ../packages/pretty.git url = http://git.haskell.org/packages/pretty.git
ignore = untracked ignore = untracked
[submodule "libraries/terminfo"] [submodule "libraries/terminfo"]
path = libraries/terminfo path = libraries/terminfo
url = ../packages/terminfo.git url = http://git.haskell.org/packages/terminfo.git
ignore = untracked ignore = untracked
[submodule "libraries/transformers"] [submodule "libraries/transformers"]
path = libraries/transformers path = libraries/transformers
url = ../packages/transformers.git url = http://git.haskell.org/packages/transformers.git
ignore = untracked ignore = untracked
[submodule "libraries/xhtml"] [submodule "libraries/xhtml"]
path = libraries/xhtml path = libraries/xhtml
url = ../packages/xhtml.git url = http://git.haskell.org/packages/xhtml.git
ignore = untracked ignore = untracked
[submodule "libraries/Win32"] [submodule "libraries/Win32"]
path = libraries/Win32 path = libraries/Win32
url = ../packages/Win32.git url = http://git.haskell.org/packages/Win32.git
ignore = untracked ignore = untracked
[submodule "libraries/primitive"] [submodule "libraries/primitive"]
path = libraries/primitive path = libraries/primitive
url = ../packages/primitive.git url = http://git.haskell.org/packages/primitive.git
ignore = untracked ignore = untracked
[submodule "libraries/vector"] [submodule "libraries/vector"]
path = libraries/vector path = libraries/vector
url = ../packages/vector.git url = http://git.haskell.org/packages/vector.git
ignore = untracked ignore = untracked
[submodule "libraries/time"] [submodule "libraries/time"]
path = libraries/time path = libraries/time
url = ../packages/time.git url = http://git.haskell.org/packages/time.git
ignore = untracked ignore = untracked
[submodule "libraries/random"] [submodule "libraries/random"]
path = libraries/random path = libraries/random
url = ../packages/random.git url = http://git.haskell.org/packages/random.git
ignore = untracked ignore = untracked
[submodule "libraries/array"] [submodule "libraries/array"]
path = libraries/array path = libraries/array
url = ../packages/array.git url = http://git.haskell.org/packages/array.git
ignore = none ignore = none
[submodule "libraries/deepseq"] [submodule "libraries/deepseq"]
path = libraries/deepseq path = libraries/deepseq
url = ../packages/deepseq.git url = http://git.haskell.org/packages/deepseq.git
ignore = none ignore = none
[submodule "libraries/directory"] [submodule "libraries/directory"]
path = libraries/directory path = libraries/directory
url = ../packages/directory.git url = http://git.haskell.org/packages/directory.git
ignore = none ignore = none
[submodule "libraries/filepath"] [submodule "libraries/filepath"]
path = libraries/filepath path = libraries/filepath
url = ../packages/filepath.git url = http://git.haskell.org/packages/filepath.git
ignore = none ignore = none
[submodule "libraries/hoopl"] [submodule "libraries/hoopl"]
path = libraries/hoopl path = libraries/hoopl
url = ../packages/hoopl.git url = http://git.haskell.org/packages/hoopl.git
ignore = none ignore = none
[submodule "libraries/hpc"] [submodule "libraries/hpc"]
path = libraries/hpc path = libraries/hpc
url = ../packages/hpc.git url = http://git.haskell.org/packages/hpc.git
ignore = none ignore = none
[submodule "libraries/process"] [submodule "libraries/process"]
path = libraries/process path = libraries/process
url = ../packages/process.git url = http://git.haskell.org/packages/process.git
ignore = none ignore = none
[submodule "libraries/unix"] [submodule "libraries/unix"]
path = libraries/unix path = libraries/unix
url = ../packages/unix.git url = http://git.haskell.org/packages/unix.git
ignore = none ignore = none
[submodule "libraries/parallel"] [submodule "libraries/parallel"]
path = libraries/parallel path = libraries/parallel
url = ../packages/parallel.git url = http://git.haskell.org/packages/parallel.git
ignore = none ignore = none
[submodule "libraries/stm"] [submodule "libraries/stm"]
path = libraries/stm path = libraries/stm
url = ../packages/stm.git url = http://git.haskell.org/packages/stm.git
ignore = none ignore = none
[submodule "libraries/dph"] [submodule "libraries/dph"]
path = libraries/dph path = libraries/dph
url = ../packages/dph.git url = http://git.haskell.org/packages/dph.git
ignore = none ignore = none
[submodule "utils/haddock"] [submodule "utils/haddock"]
path = utils/haddock path = utils/haddock
url = ../haddock.git url = http://git.haskell.org/haddock.git
ignore = none ignore = none
branch = ghc-head branch = ghc-head
[submodule "nofib"] [submodule "nofib"]
path = nofib path = nofib
url = ../nofib.git url = http://git.haskell.org/nofib.git
ignore = none ignore = none
[submodule "utils/hsc2hs"] [submodule "utils/hsc2hs"]
path = utils/hsc2hs path = utils/hsc2hs
url = ../hsc2hs.git url = http://git.haskell.org/hsc2hs.git
ignore = none ignore = none
[submodule "libffi-tarballs"] [submodule "libffi-tarballs"]
path = libffi-tarballs path = libffi-tarballs
url = ../libffi-tarballs.git url = http://git.haskell.org/libffi-tarballs.git
ignore = none ignore = none
[submodule ".arc-linters/arcanist-external-json-linter"] [submodule ".arc-linters/arcanist-external-json-linter"]
path = .arc-linters/arcanist-external-json-linter path = .arc-linters/arcanist-external-json-linter
......
The Glasgow Haskell Compiler Dependent Types Branch of GHC
============================ =============================
[![Build Status](https://api.travis-ci.org/ghc/ghc.svg?branch=master)](http://travis-ci.org/ghc/ghc) This is a fork of GHC, with work toward supporting dependent types.
Anyone is welcome to download and play with this implementation,
and I am happy to receive feedback and issue reports on GitHub.
This is the source tree for [GHC][1], a compiler and interactive There are two options of using this branch: manual, and Nix-based.
environment for the Haskell functional programming language.
For more information, visit [GHC's web site][1]. Manual
------
This code should build, but I have tested it only on `DEBUG` settings;
I recommend using build style `devel2` in `build.mk`.
Here is a minimal script you can follow to build this at home;
see the [GHC Building Guide] [3] for more info.
~~~
git clone https://github.com/goldfirere/ghc.git
cd ghc
git checkout nokinds
git remote set-url origin git://git.haskell.org/ghc.git # so submodules work
git submodule update --init
cd mk
cp build.mk.sample build.mk
## edit build.mk to uncomment the line to choose the `devel2` configuration
cd ..
perl boot
./configure
make
~~~
Check out the `testsuite/tests/dependent/should_compile` directory for
a few sample programs that should compile on this fork of GHC.
For more information about GHC, visit [GHC's web site][1].
Information for developers of GHC can be found on the [GHC Trac][2]. Information for developers of GHC can be found on the [GHC Trac][2].
Nix-based
---------
Thanks to @deepfire, this branch is available in Nixpkgs, which means that with
some effort it can be fairly automatically employed to build any package from
Hackage. This way, though, requires that one installs the Nix package manager in
parallel with the system package manager -- and this option is currently
unavailable on Windows.
Here are the instructions:
1. To install the Nix package manager, taking over /nix for package storage:
curl https://nixos.org/nix/install | sh
2. Make Nix use the `master` repository of Nixpkgs package definitions:
Getting the Source git clone https://github.com/NixOS/nixpkgs.git
================== pushd ~/.nix-defexpr
rm -rf channels
ln -s ../nixpkgs
popd
echo 'export NIX_PATH=nixpkgs=/home/---<USERNAME>---/nixpkgs' >> ~/.bashrc
export NIX_PATH=nixpkgs=/home/---<USERNAME>---/nixpkgs
There are two ways to get a source tree: 3. [OPTIONAL] To enable prebuilt binaries from Peter Simons/NixOS Hydra servers:
1. *Download source tarballs* sudo mkdir /etc/nix
echo 'binary-caches = http://hydra.nixos.org/ http://hydra.cryp.to/' | sudo dd of=/etc/nix/nix.conf
Download the GHC source distribution: # If you don't do that, everything will still work, just it'll have
# to build everything from source.
ghc-<version>-src.tar.bz2 4. Enter a shell with `ghc-nokinds` available:
which contains GHC itself and the "boot" libraries. nix-shell -p haskell.compiler.ghcNokinds
2. *Check out the source code from git* 5. See it's indeed `nokinds`:
$ git clone --recursive git://git.haskell.org/ghc.git wget https://raw.githubusercontent.com/goldfirere/ghc/nokinds/testsuite/tests/dependent/should_compile/KindEqualities2.hs
runhaskell KindEqualities2.hs
Note: cloning GHC from Github requires a special setup. See [Getting a GHC To apply 'nokinds' to building packages from Hackage, the best option would be
repository from Github] [7]. to follow instructions from the "Nix loves Haskell" talk by Peter Simons:
**DO NOT submit pull request directly to the github repo.** http://cryp.to/nixos-meetup-3-slides.pdf
*See the GHC team's working conventions re [how to contribute a patch to GHC](http://ghc.haskell.org/trac/ghc/wiki/WorkingConventions/FixingBugs "ghc.haskell.org/trac/ghc/wiki/WorkingConventions/FixingBug").*
..where the relevant compiler name would be "ghcNokinds".
Building & Installing Building & Installing
===================== =====================
......
...@@ -413,6 +413,10 @@ isBoxed :: Boxity -> Bool ...@@ -413,6 +413,10 @@ isBoxed :: Boxity -> Bool
isBoxed Boxed = True isBoxed Boxed = True
isBoxed Unboxed = False isBoxed Unboxed = False
instance Outputable Boxity where
ppr Boxed = text "Boxed"
ppr Unboxed = text "Unboxed"
{- {-
************************************************************************ ************************************************************************
* * * *
......
...@@ -32,7 +32,7 @@ import Unique ...@@ -32,7 +32,7 @@ import Unique
import Util import Util
import Name import Name
import BasicTypes import BasicTypes
import TypeRep (Type, ThetaType) import TyCoRep (Type, ThetaType)
import Var import Var
import Type (mkTyConApp) import Type (mkTyConApp)
...@@ -169,7 +169,7 @@ conLikeResTy (PatSynCon ps) tys = patSynInstResTy ps tys ...@@ -169,7 +169,7 @@ conLikeResTy (PatSynCon ps) tys = patSynInstResTy ps tys
-- --
-- 7) The original result type -- 7) The original result type
conLikeFullSig :: ConLike conLikeFullSig :: ConLike
-> ([TyVar], [TyVar], [(TyVar,Type)] -> ([TyVar], [TyVar], [EqSpec]
, ThetaType, ThetaType, [Type], Type) , ThetaType, ThetaType, [Type], Type)
conLikeFullSig (RealDataCon con) = conLikeFullSig (RealDataCon con) =
let (univ_tvs, ex_tvs, eq_spec, theta, arg_tys, res_ty) = dataConFullSig con let (univ_tvs, ex_tvs, eq_spec, theta, arg_tys, res_ty) = dataConFullSig con
......
...@@ -15,19 +15,23 @@ module DataCon ( ...@@ -15,19 +15,23 @@ module DataCon (
StrictnessMark(..), StrictnessMark(..),
ConTag, ConTag,
-- ** Equality specs
EqSpec, mkEqSpec, eqSpecTyVar, eqSpecType,
eqSpecPair, eqSpecPreds,
substEqSpec,
-- ** Field labels -- ** Field labels
FieldLbl(..), FieldLabel, FieldLabelString, FieldLbl(..), FieldLabel, FieldLabelString,
-- ** Type construction -- ** Type construction
mkDataCon, fIRST_TAG, mkDataCon, buildAlgTyCon, fIRST_TAG,
buildAlgTyCon,
-- ** Type deconstruction -- ** Type deconstruction
dataConRepType, dataConSig, dataConInstSig, dataConFullSig, dataConRepType, dataConSig, dataConInstSig, dataConFullSig,
dataConName, dataConIdentity, dataConTag, dataConTyCon, dataConName, dataConIdentity, dataConTag, dataConTyCon,
dataConOrigTyCon, dataConUserType, dataConOrigTyCon, dataConUserType,
dataConUnivTyVars, dataConExTyVars, dataConAllTyVars, dataConUnivTyVars, dataConExTyVars, dataConAllTyVars,
dataConEqSpec, eqSpecPreds, dataConTheta, dataConEqSpec, dataConTheta,
dataConStupidTheta, dataConStupidTheta,
dataConInstArgTys, dataConOrigArgTys, dataConOrigResTy, dataConInstArgTys, dataConOrigArgTys, dataConOrigResTy,
dataConInstOrigArgTys, dataConRepArgTys, dataConInstOrigArgTys, dataConRepArgTys,
...@@ -45,37 +49,32 @@ module DataCon ( ...@@ -45,37 +49,32 @@ module DataCon (
isNullarySrcDataCon, isNullaryRepDataCon, isTupleDataCon, isUnboxedTupleCon, isNullarySrcDataCon, isNullaryRepDataCon, isTupleDataCon, isUnboxedTupleCon,
isVanillaDataCon, classDataCon, dataConCannotMatch, isVanillaDataCon, classDataCon, dataConCannotMatch,
isBanged, isMarkedStrict, eqHsBang, isSrcStrict, isSrcUnpacked, isBanged, isMarkedStrict, eqHsBang, isSrcStrict, isSrcUnpacked,
specialPromotedDc, isLegacyPromotableDataCon, isLegacyPromotableTyCon,
-- ** Promotion related functions -- ** Promotion related functions
promoteDataCon, promoteDataCon_maybe, promoteDataCon
promoteType, promoteKind,
isPromotableType, computeTyConPromotability,
) where ) where
#include "HsVersions.h" #include "HsVersions.h"
import {-# SOURCE #-} MkId( DataConBoxer ) import {-# SOURCE #-} MkId( DataConBoxer )
import Type import Type
import ForeignCall( CType ) import ForeignCall ( CType )
import TypeRep( Type(..) ) -- Used in promoteType
import PrelNames( liftedTypeKindTyConKey )
import Coercion import Coercion
import Kind
import Unify import Unify
import TyCon import TyCon
import FieldLabel import FieldLabel
import Class import Class
import Name import Name
import PrelNames
import NameEnv
import Var import Var
import Outputable import Outputable
import Unique
import ListSetOps import ListSetOps
import Util import Util
import BasicTypes import BasicTypes
import FastString import FastString
import Module import Module
import VarEnv
import NameSet
import Binary import Binary
import qualified Data.Data as Data import qualified Data.Data as Data
...@@ -299,11 +298,11 @@ data DataCon ...@@ -299,11 +298,11 @@ data DataCon
-- syntax, provided its type looks like the above. -- syntax, provided its type looks like the above.
-- The declaration format is held in the TyCon (algTcGadtSyntax) -- The declaration format is held in the TyCon (algTcGadtSyntax)
dcUnivTyVars :: [TyVar], -- Universally-quantified type vars [a,b,c] dcUnivTyVars :: [TyVar], -- Universally-quantified type vars [a,b,c]
-- INVARIANT: length matches arity of the dcRepTyCon -- INVARIANT: length matches arity of the dcRepTyCon
--- result type of (rep) data con is exactly (T a b c) --- result type of (rep) data con is exactly (T a b c)
dcExTyVars :: [TyVar], -- Existentially-quantified type vars dcExTyVars :: [TyVar], -- Existentially-quantified type vars
-- In general, the dcUnivTyVars are NOT NECESSARILY THE SAME AS THE TYVARS -- In general, the dcUnivTyVars are NOT NECESSARILY THE SAME AS THE TYVARS
-- FOR THE PARENT TyCon. With GADTs the data con might not even have -- FOR THE PARENT TyCon. With GADTs the data con might not even have
-- the same number of type variables. -- the same number of type variables.
...@@ -313,8 +312,9 @@ data DataCon ...@@ -313,8 +312,9 @@ data DataCon
-- INVARIANT: the UnivTyVars and ExTyVars all have distinct OccNames -- INVARIANT: the UnivTyVars and ExTyVars all have distinct OccNames
-- Reason: less confusing, and easier to generate IfaceSyn -- Reason: less confusing, and easier to generate IfaceSyn
dcEqSpec :: [(TyVar,Type)], -- Equalities derived from the result type, dcEqSpec :: [EqSpec], -- Equalities derived from the result type,
-- _as written by the programmer_ -- _as written by the programmer_
-- This field allows us to move conveniently between the two ways -- This field allows us to move conveniently between the two ways
-- of representing a GADT constructor's type: -- of representing a GADT constructor's type:
-- MkT :: forall a b. (a ~ [b]) => b -> T a -- MkT :: forall a b. (a ~ [b]) => b -> T a
...@@ -377,8 +377,10 @@ data DataCon ...@@ -377,8 +377,10 @@ data DataCon
dcRep :: DataConRep, dcRep :: DataConRep,
-- Cached -- Cached
dcRepArity :: Arity, -- == length dataConRepArgTys -- dcRepArity == length dataConRepArgTys
dcSourceArity :: Arity, -- == length dcOrigArgTys dcRepArity :: Arity,
-- dcSourceArity == length dcOrigArgTys
dcSourceArity :: Arity,
-- Result type of constructor is T t1..tn -- Result type of constructor is T t1..tn
dcRepTyCon :: TyCon, -- Result tycon, T dcRepTyCon :: TyCon, -- Result tycon, T
...@@ -402,8 +404,8 @@ data DataCon ...@@ -402,8 +404,8 @@ data DataCon
-- Used for Template Haskell and 'deriving' only -- Used for Template Haskell and 'deriving' only
-- The actual fixity is stored elsewhere -- The actual fixity is stored elsewhere
dcPromoted :: Promoted TyCon -- The promoted TyCon if this DataCon is promotable dcPromoted :: TyCon -- The promoted TyCon
-- See Note [Promoted data constructors] in TyCon -- See Note [Promoted data constructors] in TyCon
} }
deriving Data.Typeable.Typeable deriving Data.Typeable.Typeable
...@@ -496,6 +498,40 @@ data SrcUnpackedness = SrcUnpack -- ^ {-# UNPACK #-} specified ...@@ -496,6 +498,40 @@ data SrcUnpackedness = SrcUnpack -- ^ {-# UNPACK #-} specified
-- of the DataCon *worker* fields -- of the DataCon *worker* fields
data StrictnessMark = MarkedStrict | NotMarkedStrict data StrictnessMark = MarkedStrict | NotMarkedStrict
-- | An 'EqSpec' is a tyvar/type pair representing an equality made in
-- rejigging a GADT constructor
data EqSpec = EqSpec TyVar