[commit: packages/template-haskell] master: Make Pred a type synonym of Type (issue #7021) (57b662c)
Johan Tibell
johan.tibell at gmail.com
Sat Mar 22 20:37:15 UTC 2014
What's the right way to fix libraries (e.g. aeson) that break because
classP was removed?
On Mon, Feb 10, 2014 at 2:39 AM, <git at git.haskell.org> wrote:
> Repository : ssh://git@git.haskell.org/template-haskell
>
> On branch : master
> Link :
> http://git.haskell.org/packages/template-haskell.git/commitdiff/57b662c3efd8579595c8642fce2d4cd60ba4ec0b
>
> >---------------------------------------------------------------
>
> commit 57b662c3efd8579595c8642fce2d4cd60ba4ec0b
> Author: YoEight <yo.eight at gmail.com>
> Date: Fri Jan 10 21:42:01 2014 +0100
>
> Make Pred a type synonym of Type (issue #7021)
>
> In order to make any type as a Predicate in Template Haskell, as
> allowed by ConstraintKinds
>
> Signed-off-by: Richard Eisenberg <eir at cis.upenn.edu>
>
>
> >---------------------------------------------------------------
>
> 57b662c3efd8579595c8642fce2d4cd60ba4ec0b
> Language/Haskell/TH.hs | 7 +++----
> Language/Haskell/TH/Lib.hs | 21 ++++++++-------------
> Language/Haskell/TH/Ppr.hs | 8 ++------
> Language/Haskell/TH/Syntax.hs | 6 ++----
> 4 files changed, 15 insertions(+), 27 deletions(-)
>
> diff --git a/Language/Haskell/TH.hs b/Language/Haskell/TH.hs
> index 2ab19bd..e9765a9 100644
> --- a/Language/Haskell/TH.hs
> +++ b/Language/Haskell/TH.hs
> @@ -68,7 +68,7 @@ module Language.Haskell.TH(
> -- ** Patterns
> Pat(..), FieldExp, FieldPat,
> -- ** Types
> - Type(..), TyVarBndr(..), TyLit(..), Kind, Cxt, Pred(..),
> Syntax.Role(..),
> + Type(..), TyVarBndr(..), TyLit(..), Kind, Cxt, Pred,
> Syntax.Role(..),
>
> -- * Library functions
> -- ** Abbreviations
> @@ -105,14 +105,14 @@ module Language.Haskell.TH(
> bindS, letS, noBindS, parS,
>
> -- *** Types
> - forallT, varT, conT, appT, arrowT, listT, tupleT, sigT, litT,
> + forallT, varT, conT, appT, arrowT, equalityT, listT, tupleT, sigT,
> litT,
> promotedT, promotedTupleT, promotedNilT, promotedConsT,
> -- **** Type literals
> numTyLit, strTyLit,
> -- **** Strictness
> isStrict, notStrict, strictType, varStrictType,
> -- **** Class Contexts
> - cxt, classP, equalP, normalC, recC, infixC, forallC,
> + cxt, normalC, recC, infixC, forallC,
>
> -- *** Kinds
> varK, conK, tupleK, arrowK, listK, appK, starK, constraintK,
> @@ -146,4 +146,3 @@ module Language.Haskell.TH(
> import Language.Haskell.TH.Syntax as Syntax
> import Language.Haskell.TH.Lib
> import Language.Haskell.TH.Ppr
> -
> diff --git a/Language/Haskell/TH/Lib.hs b/Language/Haskell/TH/Lib.hs
> index b7a88d6..17e794b 100644
> --- a/Language/Haskell/TH/Lib.hs
> +++ b/Language/Haskell/TH/Lib.hs
> @@ -466,19 +466,6 @@ tySynEqn lhs rhs =
> cxt :: [PredQ] -> CxtQ
> cxt = sequence
>
> -classP :: Name -> [TypeQ] -> PredQ
> -classP cla tys
> - = do
> - tys1 <- sequence tys
> - return (ClassP cla tys1)
> -
> -equalP :: TypeQ -> TypeQ -> PredQ
> -equalP tleft tright
> - = do
> - tleft1 <- tleft
> - tright1 <- tright
> - return (EqualP tleft1 tright1)
> -
> normalC :: Name -> [StrictTypeQ] -> ConQ
> normalC con strtys = liftM (NormalC con) $ sequence strtys
>
> @@ -536,6 +523,14 @@ sigT t k
> t' <- t
> return $ SigT t' k
>
> +equalityT :: TypeQ -> TypeQ -> TypeQ
> +equalityT tleft tright
> + = do
> + tleft1 <- tleft
> + tright1 <- tright
> + let typ = AppT (AppT EqualityT tleft1) tright1
> + return typ
> +
> promotedT :: Name -> TypeQ
> promotedT = return . PromotedT
>
> diff --git a/Language/Haskell/TH/Ppr.hs b/Language/Haskell/TH/Ppr.hs
> index 2023f3a..e237066 100644
> --- a/Language/Haskell/TH/Ppr.hs
> +++ b/Language/Haskell/TH/Ppr.hs
> @@ -496,6 +496,8 @@ instance Ppr Type where
>
> pprTyApp :: (Type, [Type]) -> Doc
> pprTyApp (ArrowT, [arg1,arg2]) = sep [pprFunArgType arg1 <+> text "->",
> ppr arg2]
> +pprTyApp (EqualityT, [arg1, arg2]) =
> + sep [pprFunArgType arg1 <+> text "~", ppr arg2]
> pprTyApp (ListT, [arg]) = brackets (ppr arg)
> pprTyApp (TupleT n, args)
> | length args == n = parens (sep (punctuate comma (map ppr args)))
> @@ -540,11 +542,6 @@ pprCxt [t] = ppr t <+> text "=>"
> pprCxt ts = parens (sep $ punctuate comma $ map ppr ts) <+> text "=>"
>
> ------------------------------
> -instance Ppr Pred where
> - ppr (ClassP cla tys) = ppr cla <+> sep (map pprParendType tys)
> - ppr (EqualP ty1 ty2) = pprFunArgType ty1 <+> char '~' <+> pprFunArgType
> ty2
> -
> -------------------------------
> instance Ppr Range where
> ppr = brackets . pprRange
> where pprRange :: Range -> Doc
> @@ -569,4 +566,3 @@ hashParens d = text "(# " <> d <> text " #)"
>
> quoteParens :: Doc -> Doc
> quoteParens d = text "'(" <> d <> text ")"
> -
> diff --git a/Language/Haskell/TH/Syntax.hs b/Language/Haskell/TH/Syntax.hs
> index 3606f9d..17bb065 100644
> --- a/Language/Haskell/TH/Syntax.hs
> +++ b/Language/Haskell/TH/Syntax.hs
> @@ -1346,9 +1346,7 @@ data AnnTarget = ModuleAnnotation
>
> type Cxt = [Pred] -- ^ @(Eq a, Ord b)@
>
> -data Pred = ClassP Name [Type] -- ^ @Eq (Int, a)@
> - | EqualP Type Type -- ^ @F a ~ Bool@
> - deriving( Show, Eq, Data, Typeable )
> +type Pred = Type
>
> data Strict = IsStrict | NotStrict | Unpacked
> deriving( Show, Eq, Data, Typeable )
> @@ -1373,6 +1371,7 @@ data Type = ForallT [TyVarBndr] Cxt Type -- ^
> @forall \<vars\>. \<ctxt\> -> \<t
> | TupleT Int -- ^ @(,), (,,), etc.@
> | UnboxedTupleT Int -- ^ @(#,#), (#,,#), etc.@
> | ArrowT -- ^ @->@
> + | EqualityT -- ^ @~@
> | ListT -- ^ @[]@
> | PromotedTupleT Int -- ^ @'(), '(,), '(,,), etc.@
> | PromotedNilT -- ^ @'[]@
> @@ -1453,4 +1452,3 @@ cmpEq _ = False
> thenCmp :: Ordering -> Ordering -> Ordering
> thenCmp EQ o2 = o2
> thenCmp o1 _ = o1
> -
>
> _______________________________________________
> ghc-commits mailing list
> ghc-commits at haskell.org
> http://www.haskell.org/mailman/listinfo/ghc-commits
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.haskell.org/pipermail/ghc-devs/attachments/20140322/d82018ae/attachment.html>
More information about the ghc-devs
mailing list