\begin{code}
module HsTypes (
- HsType(..), HsUsageAnn(..), HsTyVarBndr(..),
+ HsType(..), HsTyVarBndr(..), HsTyOp(..),
, HsContext, HsPred(..)
, HsTupCon(..), hsTupParens, mkHsTupCon,
+ , hsUsOnce, hsUsMany
- , mkHsForAllTy, mkHsUsForAllTy, mkHsDictTy, mkHsIParamTy
+ , mkHsForAllTy, mkHsDictTy, mkHsIParamTy
, hsTyVarName, hsTyVarNames, replaceTyVarName
+ , getHsInstHead
+
+ -- Type place holder
+ , PostTcType, placeHolderType,
+
+ -- Name place holder
+ , SyntaxName, placeHolderName,
-- Printing
- , pprParendHsType, pprHsForAll, pprHsContext, pprHsTyVarBndr
+ , pprParendHsType, pprHsForAll, pprHsContext, ppr_hs_context, pprHsTyVarBndr
-- Equality over Hs things
, EqHsEnv, emptyEqHsEnv, extendEqHsEnv,
#include "HsVersions.h"
import Class ( FunDep )
-import Type ( Type, Kind, PredType(..), ClassContext,
- splitSigmaTy, unUsgTy, boxedTypeKind
+import TcType ( Type, Kind, ThetaType, SourceType(..),
+ tcSplitSigmaTy, liftedTypeKind, eqKind, tcEqType
)
import TypeRep ( Type(..), TyNote(..) ) -- toHsType sees the representation
-import TyCon ( isTupleTyCon, tupleTyConBoxity, tyConArity )
-import RdrName ( RdrName )
-import Name ( Name, getName )
-import OccName ( NameSpace )
+import TyCon ( isTupleTyCon, tupleTyConBoxity, tyConArity, isNewTyCon, getSynTyConDefn )
+import RdrName ( RdrName, mkUnqual )
+import Name ( Name, getName, mkInternalName )
+import OccName ( NameSpace, mkVarOcc, tvName )
import Var ( TyVar, tyVarKind )
-import PprType ( {- instance Outputable Kind -}, pprParendKind )
-import BasicTypes ( Boxity(..), tupleParens )
-import PrelNames ( mkTupConRdrName, listTyConKey, hasKey )
+import Subst ( substTyWith )
+import PprType ( {- instance Outputable Kind -}, pprParendKind, pprKind )
+import BasicTypes ( Boxity(..), Arity, IPName, tupleParens )
+import PrelNames ( mkTupConRdrName, listTyConKey, parrTyConKey,
+ usOnceTyConKey, usManyTyConKey, hasKey, unboundKey,
+ usOnceTyConName, usManyTyConName )
+import SrcLoc ( builtinSrcLoc )
+import Util ( eqListBy, lengthIs )
import FiniteMap
import Outputable
+\end{code}
+
+
+%************************************************************************
+%* *
+\subsection{Annotating the syntax}
+%* *
+%************************************************************************
+
+\begin{code}
+type PostTcType = Type -- Used for slots in the abstract syntax
+ -- where we want to keep slot for a type
+ -- to be added by the type checker...but
+ -- before typechecking it's just bogus
+
+placeHolderType :: PostTcType -- Used before typechecking
+placeHolderType = panic "Evaluated the place holder for a PostTcType"
+
+
+type SyntaxName = Name -- These names are filled in by the renamer
+ -- Before then they are a placeHolderName (so that
+ -- we can still print the HsSyn)
+ -- They correspond to "rebindable syntax";
+ -- See RnEnv.lookupSyntaxName
+placeHolderName :: SyntaxName
+placeHolderName = mkInternalName unboundKey
+ (mkVarOcc FSLIT("syntaxPlaceHolder"))
+ builtinSrcLoc
\end{code}
+
+%************************************************************************
+%* *
+\subsection{Data types}
+%* *
+%************************************************************************
+
This is the syntax for types as seen in type signatures.
\begin{code}
type HsContext name = [HsPred name]
-data HsPred name = HsPClass name [HsType name]
- | HsPIParam name (HsType name)
+data HsPred name = HsClassP name [HsType name]
+ | HsIParam (IPName name) (HsType name)
data HsType name
= HsForAllTy (Maybe [HsTyVarBndr name]) -- Nothing for implicitly quantified signatures
| HsAppTy (HsType name)
(HsType name)
- | HsFunTy (HsType name) -- function type
+ | HsFunTy (HsType name) -- function type
(HsType name)
| HsListTy (HsType name) -- Element type
+ | HsPArrTy (HsType name) -- Elem. type of parallel array: [:t:]
+
| HsTupleTy (HsTupCon name)
[HsType name] -- Element types (length gives arity)
- -- Generics
- | HsOpTy (HsType name) name (HsType name)
- | HsNumTy Integer
+
+ | HsOpTy (HsType name) (HsTyOp name) (HsType name)
+
+ | HsParTy (HsType name) -- Parenthesis preserved for the
+ -- precedence parser; are removed by
+ -- the type checker
+
+ | HsNumTy Integer -- Generics only
+
-- these next two are only used in interfaces
| HsPredTy (HsPred name)
- | HsUsgTy (HsUsageAnn name)
- (HsType name)
+ | HsKindSig (HsType name) -- (ty :: kind)
+ Kind -- A type with a kind signature
- | HsUsgForAllTy name
- (HsType name)
-data HsUsageAnn name
- = HsUsOnce
- | HsUsMany
- | HsUsVar name
-
+data HsTyOp name = HsArrow | HsTyOp name
+ -- Function arrows from *source* get read in as HsOpTy t1 HsArrow t2
+ -- But when we generate or parse interface files, we use HsFunTy.
+ -- This keeps interfaces a bit smaller, because there are a lot of arrows
+
+-----------------------
+hsUsOnce, hsUsMany :: HsType RdrName
+hsUsOnce = HsTyVar (mkUnqual tvName FSLIT(".")) -- deep magic
+hsUsMany = HsTyVar (mkUnqual tvName FSLIT("!")) -- deep magic
+
+hsUsOnce_Name, hsUsMany_Name :: HsType Name
+hsUsOnce_Name = HsTyVar usOnceTyConName
+hsUsMany_Name = HsTyVar usManyTyConName
-----------------------
-data HsTupCon name = HsTupCon name Boxity
+data HsTupCon name = HsTupCon name Boxity Arity
instance Eq name => Eq (HsTupCon name) where
- (HsTupCon _ b1) == (HsTupCon _ b2) = b1==b2
+ (HsTupCon _ b1 a1) == (HsTupCon _ b2 a2) = b1==b2 && a1==a2
mkHsTupCon :: NameSpace -> Boxity -> [a] -> HsTupCon RdrName
-mkHsTupCon space boxity args = HsTupCon (mkTupConRdrName space boxity (length args)) boxity
+mkHsTupCon space boxity args = HsTupCon (mkTupConRdrName space boxity arity) boxity arity
+ where
+ arity = length args
hsTupParens :: HsTupCon name -> SDoc -> SDoc
-hsTupParens (HsTupCon _ b) p = tupleParens b p
+hsTupParens (HsTupCon _ b _) p = tupleParens b p
-----------------------
-- Combine adjacent for-alls.
(Just tvs1) `plus` (Just tvs2) = Just (tvs1 ++ tvs2)
mkHsForAllTy tvs ctxt ty = HsForAllTy tvs ctxt ty
-mkHsUsForAllTy uvs ty = foldr (\ uv ty -> HsUsgForAllTy uv ty)
- ty uvs
-
-mkHsDictTy cls tys = HsPredTy (HsPClass cls tys)
-mkHsIParamTy v ty = HsPredTy (HsPIParam v ty)
+mkHsDictTy cls tys = HsPredTy (HsClassP cls tys)
+mkHsIParamTy v ty = HsPredTy (HsIParam v ty)
data HsTyVarBndr name
= UserTyVar name
\end{code}
+\begin{code}
+getHsInstHead :: HsType name -> ([HsTyVarBndr name], (name, [HsType name]))
+ -- Split up an instance decl type, returning the 'head' part
+
+-- In interface fiels, the type of the decl is held like this:
+-- forall a. Foo a -> Baz (T a)
+-- so we have to strip off function argument types,
+-- as well as the bit before the '=>' (which is always
+-- empty in interface files)
+--
+-- The parser ensures the type will have the right shape.
+-- (e.g. see ParseUtil.checkInstType)
+
+getHsInstHead (HsForAllTy (Just tvs) _ tau) = (tvs, get_head1 tau)
+getHsInstHead tau = ([], get_head1 tau)
+
+get_head1 (HsFunTy _ ty) = get_head1 ty
+get_head1 (HsPredTy (HsClassP cls tys)) = (cls,tys)
+\end{code}
+
+
%************************************************************************
%* *
\subsection{Pretty printing}
instance (Outputable name) => Outputable (HsType name) where
ppr ty = pprHsType ty
+instance (Outputable name) => Outputable (HsTyOp name) where
+ ppr HsArrow = ftext FSLIT("->")
+ ppr (HsTyOp n) = ppr n
+
instance (Outputable name) => Outputable (HsTyVarBndr name) where
ppr (UserTyVar name) = ppr name
ppr (IfaceTyVar name kind) = pprHsTyVarBndr name kind
instance Outputable name => Outputable (HsPred name) where
- ppr (HsPClass clas tys) = ppr clas <+> hsep (map pprParendHsType tys)
- ppr (HsPIParam n ty) = hsep [char '?' <> ppr n, text "::", ppr ty]
+ ppr (HsClassP clas tys) = ppr clas <+> hsep (map pprParendHsType tys)
+ ppr (HsIParam n ty) = hsep [ppr n, dcolon, ppr ty]
pprHsTyVarBndr :: Outputable name => name -> Kind -> SDoc
-pprHsTyVarBndr name kind | kind == boxedTypeKind = ppr name
- | otherwise = hsep [ppr name, dcolon, pprParendKind kind]
+pprHsTyVarBndr name kind | kind `eqKind` liftedTypeKind = ppr name
+ | otherwise = hsep [ppr name, dcolon, pprParendKind kind]
pprHsForAll [] [] = empty
pprHsForAll tvs cxt
= getPprStyle $ \ sty ->
if userStyle sty then
ptext SLIT("forall") <+> interppSP tvs <> dot <+>
- (if null cxt then
- empty
- else
- ppr_context cxt <+> ptext SLIT("=>")
- )
+ -- **! ToDo: want to hide uvars from user, but not enough info
+ -- in a HsTyVarBndr name (see PprType). KSW 2000-10.
+ pprHsContext cxt
else -- Used in interfaces
ptext SLIT("__forall") <+> interppSP tvs <+>
- ppr_context cxt <+> ptext SLIT("=>")
+ ppr_hs_context cxt <+> ptext SLIT("=>")
pprHsContext :: (Outputable name) => HsContext name -> SDoc
pprHsContext [] = empty
-pprHsContext cxt = ppr_context cxt <+> ptext SLIT("=>")
+pprHsContext cxt = ppr_hs_context cxt <+> ptext SLIT("=>")
-ppr_context [] = empty
-ppr_context cxt = parens (interpp'SP cxt)
+ppr_hs_context [] = empty
+ppr_hs_context cxt = parens (interpp'SP cxt)
\end{code}
\begin{code}
-pREC_TOP = (0 :: Int)
-pREC_FUN = (1 :: Int)
-pREC_CON = (2 :: Int)
+pREC_TOP = (0 :: Int) -- type in ParseIface.y
+pREC_FUN = (1 :: Int) -- btype in ParseIface.y
+pREC_CON = (2 :: Int) -- atype in ParseIface.y
maybeParen :: Bool -> SDoc -> SDoc
maybeParen True p = parens p
(sep [p1, (<>) (ptext SLIT("-> ")) p2])
ppr_mono_ty ctxt_prec (HsTupleTy con tys) = hsTupParens con (interpp'SP tys)
+ppr_mono_ty ctxt_prec (HsKindSig ty kind) = parens (ppr_mono_ty pREC_TOP ty <+> dcolon <+> pprKind kind)
ppr_mono_ty ctxt_prec (HsListTy ty) = brackets (ppr_mono_ty pREC_TOP ty)
+ppr_mono_ty ctxt_prec (HsPArrTy ty) = pabrackets (ppr_mono_ty pREC_TOP ty)
+ where
+ pabrackets p = ptext SLIT("[:") <> p <> ptext SLIT(":]")
-ppr_mono_ty ctxt_prec (HsAppTy fun_ty arg_ty)
- = maybeParen (ctxt_prec >= pREC_CON)
- (hsep [ppr_mono_ty pREC_FUN fun_ty, ppr_mono_ty pREC_CON arg_ty])
+ppr_mono_ty ctxt_prec (HsAppTy fun_ty arg_ty) =
+ maybeParen (ctxt_prec >= pREC_CON)
+ (hsep [ppr_mono_ty pREC_FUN fun_ty, ppr_mono_ty pREC_CON arg_ty])
ppr_mono_ty ctxt_prec (HsPredTy pred)
- = maybeParen (ctxt_prec >= pREC_FUN) $
- braces (ppr pred)
+ = braces (ppr pred)
-ppr_mono_ty ctxt_prec ty@(HsUsgForAllTy _ _)
- =
- sep [ ptext SLIT("__fuall") <+> brackets pp_uvars <+> ptext SLIT("=>"),
- ppr_mono_ty pREC_TOP sigma
- ]
- where
- (uvars,sigma) = split [] ty
- pp_uvars = interppSP uvars
+ppr_mono_ty ctxt_prec (HsOpTy ty1 op ty2) =
+ maybeParen (ctxt_prec >= pREC_FUN)
+ (ppr_mono_ty pREC_FUN ty1 <+> ppr op <+> ppr_mono_ty pREC_FUN ty2)
- split uvs (HsUsgForAllTy uv ty') = split (uv:uvs) ty'
- split uvs ty' = (reverse uvs,ty')
+ppr_mono_ty ctxt_prec (HsParTy ty) = ppr_mono_ty ctxt_prec ty
+ -- `HsParTy' isn't useful for pretty printing, as it is removed by the type
+ -- checker and we need to be able to pretty print after type checking
-ppr_mono_ty ctxt_prec (HsUsgTy u ty)
- = maybeParen (ctxt_prec >= pREC_CON) $
- ptext SLIT("__u") <+> pp_ua <+> ppr_mono_ty pREC_CON ty
- where
- pp_ua = case u of
- HsUsOnce -> ptext SLIT("-")
- HsUsMany -> ptext SLIT("!")
- HsUsVar uv -> ppr uv
--- Generics
-ppr_mono_ty ctxt_prec (HsNumTy n) = integer n
-ppr_mono_ty ctxt_prec (HsOpTy ty1 op ty2) = ppr ty1 <+> ppr op <+> ppr ty2
+ppr_mono_ty ctxt_prec (HsNumTy n) = integer n -- generics only
\end{code}
toHsTyVars tvs = map toHsTyVar tvs
toHsType :: Type -> HsType Name
-toHsType ty = toHsType' (unUsgTy ty)
- -- For now we just discard the usage
-
-toHsType' :: Type -> HsType Name
--- Called after the usage is stripped off
-- This function knows the representation of types
-toHsType' (TyVarTy tv) = HsTyVar (getName tv)
-toHsType' (FunTy arg res) = HsFunTy (toHsType arg) (toHsType res)
-toHsType' (AppTy fun arg) = HsAppTy (toHsType fun) (toHsType arg)
-
-toHsType' (NoteTy (SynNote ty) _) = toHsType ty -- Use synonyms if possible!!
-toHsType' (NoteTy _ ty) = toHsType ty
-
-toHsType' (PredTy p) = HsPredTy (toHsPred p)
-
-toHsType' ty@(TyConApp tc tys) -- Must be saturated because toHsType's arg is of kind *
- | not saturated = generic_case
- | isTupleTyCon tc = HsTupleTy (HsTupCon (getName tc) (tupleTyConBoxity tc)) tys'
- | tc `hasKey` listTyConKey = HsListTy (head tys')
- | otherwise = generic_case
+toHsType (TyVarTy tv) = HsTyVar (getName tv)
+toHsType (FunTy arg res) = HsFunTy (toHsType arg) (toHsType res)
+toHsType (AppTy fun arg) = HsAppTy (toHsType fun) (toHsType arg)
+
+toHsType (NoteTy (SynNote ty@(TyConApp tycon tyargs)) real_ty)
+ | isNewTyCon tycon = toHsType ty
+ | syn_matches = toHsType ty -- Use synonyms if possible!!
+ | otherwise =
+#ifdef DEBUG
+ pprTrace "WARNING: synonym info lost in .hi file for " (ppr syn_ty) $
+#endif
+ toHsType real_ty -- but drop it if not.
+ where
+ syn_matches = ty_from_syn `tcEqType` real_ty
+ (tyvars,syn_ty) = getSynTyConDefn tycon
+ ty_from_syn = substTyWith tyvars tyargs syn_ty
+
+ -- We only use the type synonym in the file if this doesn't cause
+ -- us to lose important information. This matters for usage
+ -- annotations. It's an issue if some of the args to the synonym
+ -- have arrows in them, or if the synonym's RHS has an arrow; for
+ -- example, with nofib/real/ebnf2ps/ in Parsers.using.
+
+ -- **! It would be nice if when this test fails we could still
+ -- write the synonym in as a Note, so we don't lose the info for
+ -- error messages, but it's too much work for right now.
+ -- KSW 2000-07.
+
+toHsType (NoteTy _ ty) = toHsType ty
+
+toHsType (SourceTy (NType tc tys)) = foldl HsAppTy (HsTyVar (getName tc)) (map toHsType tys)
+toHsType (SourceTy pred) = HsPredTy (toHsPred pred)
+
+toHsType ty@(TyConApp tc tys) -- Must be saturated because toHsType's arg is of kind *
+ | not saturated = generic_case
+ | isTupleTyCon tc = HsTupleTy (HsTupCon (getName tc) (tupleTyConBoxity tc) (tyConArity tc)) tys'
+ | tc `hasKey` listTyConKey = HsListTy (head tys')
+ | tc `hasKey` parrTyConKey = HsPArrTy (head tys')
+ | tc `hasKey` usOnceTyConKey = hsUsOnce_Name -- must print !, . unqualified
+ | tc `hasKey` usManyTyConKey = hsUsMany_Name -- must print !, . unqualified
+ | otherwise = generic_case
where
generic_case = foldl HsAppTy (HsTyVar (getName tc)) tys'
tys' = map toHsType tys
- saturated = length tys == tyConArity tc
+ saturated = tys `lengthIs` tyConArity tc
-toHsType' ty@(ForAllTy _ _) = case splitSigmaTy ty of
+toHsType ty@(ForAllTy _ _) = case tcSplitSigmaTy ty of
(tvs, preds, tau) -> HsForAllTy (Just (map toHsTyVar tvs))
(map toHsPred preds)
(toHsType tau)
+toHsPred (ClassP cls tys) = HsClassP (getName cls) (map toHsType tys)
+toHsPred (IParam n ty) = HsIParam n (toHsType ty)
-toHsPred (Class cls tys) = HsPClass (getName cls) (map toHsType tys)
-toHsPred (IParam n ty) = HsPIParam (getName n) (toHsType ty)
-
-toHsContext :: ClassContext -> HsContext Name
-toHsContext cxt = [HsPClass (getName cls) (map toHsType tys) | (cls,tys) <- cxt]
+toHsContext :: ThetaType -> HsContext Name
+toHsContext theta = map toHsPred theta
toHsFDs :: [FunDep TyVar] -> [FunDep Name]
toHsFDs fds = [(map getName ns, map getName ms) | (ns,ms) <- fds]
eq_hsTyVars env _ _ _ = False
eq_hsTyVar env (UserTyVar v1) (UserTyVar v2) k = k (extendEqHsEnv env v1 v2)
-eq_hsTyVar env (IfaceTyVar v1 k1) (IfaceTyVar v2 k2) k = k1 == k2 && k (extendEqHsEnv env v1 v2)
+eq_hsTyVar env (IfaceTyVar v1 k1) (IfaceTyVar v2 k2) k = k1 `eqKind` k2 && k (extendEqHsEnv env v1 v2)
eq_hsTyVar env _ _ _ = False
eq_hsVars env [] [] k = k env
eq_hsType env (HsListTy ty1) (HsListTy ty2)
= eq_hsType env ty1 ty2
+eq_hsType env (HsKindSig ty1 k1) (HsKindSig ty2 k2)
+ = eq_hsType env ty1 ty2 && k1 `eqKind` k2
+
+eq_hsType env (HsPArrTy ty1) (HsPArrTy ty2)
+ = eq_hsType env ty1 ty2
+
eq_hsType env (HsAppTy fun_ty1 arg_ty1) (HsAppTy fun_ty2 arg_ty2)
= eq_hsType env fun_ty1 fun_ty2 && eq_hsType env arg_ty1 arg_ty2
= eq_hsPred env p1 p2
eq_hsType env (HsOpTy lty1 op1 rty1) (HsOpTy lty2 op2 rty2)
- = eq_hsVar env op1 op2 && eq_hsType env lty1 lty2 && eq_hsType env rty1 rty2
-
-eq_hsType env (HsUsgTy u1 ty1) (HsUsgTy u2 ty2)
- = eqUsg u1 u2 && eq_hsType env ty1 ty2
+ = eq_hsOp env op1 op2 && eq_hsType env lty1 lty2 && eq_hsType env rty1 rty2
eq_hsType env ty1 ty2 = False
+eq_hsOp env (HsTyOp n1) (HsTyOp n2) = eq_hsVar env n1 n2
+eq_hsOp env HsArrow HsArrow = True
+eq_hsOp env op1 op2 = False
+
-------------------
eq_hsContext env a b = eqListBy (eq_hsPred env) a b
-------------------
-eq_hsPred env (HsPClass c1 tys1) (HsPClass c2 tys2)
+eq_hsPred env (HsClassP c1 tys1) (HsClassP c2 tys2)
= c1 == c2 && eq_hsTypes env tys1 tys2
-eq_hsPred env (HsPIParam n1 ty1) (HsPIParam n2 ty2)
+eq_hsPred env (HsIParam n1 ty1) (HsIParam n2 ty2)
= n1 == n2 && eq_hsType env ty1 ty2
eq_hsPred env _ _ = False
-
--------------------
-eqUsg HsUsOnce HsUsOnce = True
-eqUsg HsUsMany HsUsMany = True
-eqUsg (HsUsVar u1) (HsUsVar u2) = u1 == u2
-eqUsg _ _ = False
-
--------------------
-eqListBy :: (a->a->Bool) -> [a] -> [a] -> Bool
-eqListBy eq [] [] = True
-eqListBy eq (x:xs) (y:ys) = eq x y && eqListBy eq xs ys
-eqListBy eq xs ys = False
\end{code}
projects / ghc-hetmet.git / blobdiff