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| author | Sebastian Graf <sgraf1337@gmail.com> | 2019-11-03 19:42:52 +0000 |
|---|---|---|
| committer | Marge Bot <ben+marge-bot@smart-cactus.org> | 2021-03-14 12:54:29 -0400 |
| commit | b73c9c5face16cc8bedf4168ce10770c7cc67f80 (patch) | |
| tree | 9e5b60b2cfd7ddbae3562c21e838a797fe7539f0 /compiler/GHC/Tc/Utils | |
| parent | 96b3c66b50c77c105dd97b7ef9b44d0779d712b1 (diff) | |
| download | haskell-b73c9c5face16cc8bedf4168ce10770c7cc67f80.tar.gz | |
Implement the UnliftedDatatypes extension
GHC Proposal: 0265-unlifted-datatypes.rst
Discussion: https://github.com/ghc-proposals/ghc-proposals/pull/265
Issues: https://gitlab.haskell.org/ghc/ghc/-/issues/19523
Implementation Details: Note [Implementation of UnliftedDatatypes]
This patch introduces the `UnliftedDatatypes` extension. When this extension is
enabled, GHC relaxes the restrictions around what result kinds are allowed in
data declarations. This allows data types for which an unlifted or
levity-polymorphic result kind is inferred.
The most significant changes are in `GHC.Tc.TyCl`, where
`Note [Implementation of UnliftedDatatypes]` describes the details of the
implementation.
Fixes #19523.
Diffstat (limited to 'compiler/GHC/Tc/Utils')
| -rw-r--r-- | compiler/GHC/Tc/Utils/TcMType.hs | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/compiler/GHC/Tc/Utils/TcMType.hs b/compiler/GHC/Tc/Utils/TcMType.hs index a3cda06cac..b6f5065997 100644 --- a/compiler/GHC/Tc/Utils/TcMType.hs +++ b/compiler/GHC/Tc/Utils/TcMType.hs @@ -23,6 +23,7 @@ module GHC.Tc.Utils.TcMType ( newFlexiTyVarTy, -- Kind -> TcM TcType newFlexiTyVarTys, -- Int -> Kind -> TcM [TcType] newOpenFlexiTyVar, newOpenFlexiTyVarTy, newOpenTypeKind, + newOpenBoxedTypeKind, newMetaKindVar, newMetaKindVars, newMetaTyVarTyAtLevel, newAnonMetaTyVar, cloneMetaTyVar, newCycleBreakerTyVar, @@ -1075,6 +1076,12 @@ newOpenFlexiTyVar = do { kind <- newOpenTypeKind ; newFlexiTyVar kind } +newOpenBoxedTypeKind :: TcM TcKind +newOpenBoxedTypeKind + = do { lev <- newFlexiTyVarTy (mkTyConTy levityTyCon) + ; let rr = mkTyConApp boxedRepDataConTyCon [lev] + ; return (tYPE rr) } + newMetaTyVars :: [TyVar] -> TcM (TCvSubst, [TcTyVar]) -- Instantiate with META type variables -- Note that this works for a sequence of kind, type, and coercion variables |