X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2FhsSyn%2FHsTypes.lhs;h=2c6716fc07549277f5b7b738fc9cf3c895db85c9;hb=957bf3756ffd56f5329a2aabe1022d6f996dd641;hp=6976ff2ab302c1c56aff11af46ef69468757749c;hpb=32a895831dbc202fab780fdd8bee65be81e2d232;p=ghc-hetmet.git diff --git a/ghc/compiler/hsSyn/HsTypes.lhs b/ghc/compiler/hsSyn/HsTypes.lhs index 6976ff2..2c6716f 100644 --- a/ghc/compiler/hsSyn/HsTypes.lhs +++ b/ghc/compiler/hsSyn/HsTypes.lhs @@ -5,19 +5,22 @@ \begin{code} module HsTypes ( - HsType(..), HsTyVarBndr(..), + HsType(..), HsTyVarBndr(..), HsTyOp(..), , HsContext, HsPred(..) , HsTupCon(..), hsTupParens, mkHsTupCon, - , hsUsOnce, hsUsMany , mkHsForAllTy, mkHsDictTy, mkHsIParamTy - , hsTyVarName, hsTyVarNames, replaceTyVarName, + , hsTyVarName, hsTyVarNames, replaceTyVarName + , splitHsInstDeclTy -- Type place holder - PostTcType, placeHolderType, + , 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, @@ -36,17 +39,17 @@ import TcType ( Type, Kind, ThetaType, SourceType(..), import TypeRep ( Type(..), TyNote(..) ) -- toHsType sees the representation import TyCon ( isTupleTyCon, tupleTyConBoxity, tyConArity, isNewTyCon, getSynTyConDefn ) import RdrName ( RdrName, mkUnqual ) -import Name ( Name, getName ) -import OccName ( NameSpace, tvName ) +import Name ( Name, getName, mkInternalName ) +import OccName ( NameSpace, mkVarOcc, tvName ) import Var ( TyVar, tyVarKind ) import Subst ( substTyWith ) -import PprType ( {- instance Outputable Kind -}, pprParendKind ) +import PprType ( {- instance Outputable Kind -}, pprParendKind, pprKind ) import BasicTypes ( Boxity(..), Arity, IPName, tupleParens ) -import PrelNames ( mkTupConRdrName, listTyConKey, usOnceTyConKey, usManyTyConKey, hasKey, - usOnceTyConName, usManyTyConName - ) -import FiniteMap +import PrelNames ( listTyConKey, parrTyConKey, + hasKey, unboundKey ) +import SrcLoc ( noSrcLoc ) import Util ( eqListBy, lengthIs ) +import FiniteMap import Outputable \end{code} @@ -65,6 +68,18 @@ type PostTcType = Type -- Used for slots in the abstract syntax 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")) + noSrcLoc \end{code} @@ -92,46 +107,51 @@ data HsType name | HsAppTy (HsType name) (HsType name) - | HsFunTy (HsType name) -- function type + | HsFunTy (HsType name) -- function type (HsType name) | HsListTy (HsType name) -- Element type - | HsTupleTy (HsTupCon name) + | HsPArrTy (HsType name) -- Elem. type of parallel array: [:t:] + + | HsTupleTy HsTupCon [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 re-arrangement in RnTypes + -- It's important that a * (b + c) doesn't get rearranged to (a*b) + c! + -- + -- However, NB that toHsType doesn't add HsParTys (in an effort to keep + -- interface files smaller), so when printing a HsType we may need to + -- add parens. + + | HsNumTy Integer -- Generics only -- these next two are only used in interfaces | HsPredTy (HsPred name) - - | HsUsageTy (HsType name) -- Usage annotation - (HsType name) -- Annotated type + | HsKindSig (HsType name) -- (ty :: kind) + Kind -- A type with a kind signature ------------------------ -hsUsOnce, hsUsMany :: HsType RdrName -hsUsOnce = HsTyVar (mkUnqual tvName SLIT(".")) -- deep magic -hsUsMany = HsTyVar (mkUnqual tvName SLIT("!")) -- deep magic -hsUsOnce_Name, hsUsMany_Name :: HsType Name -hsUsOnce_Name = HsTyVar usOnceTyConName -hsUsMany_Name = HsTyVar usManyTyConName +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 ----------------------- -data HsTupCon name = HsTupCon name Boxity Arity +data HsTupCon = HsTupCon Boxity Arity -instance Eq name => Eq (HsTupCon name) where - (HsTupCon _ b1 a1) == (HsTupCon _ b2 a2) = b1==b2 && a1==a2 +instance Eq HsTupCon where + (HsTupCon b1 a1) == (HsTupCon b2 a2) = b1==b2 && a1==a2 -mkHsTupCon :: NameSpace -> Boxity -> [a] -> HsTupCon RdrName -mkHsTupCon space boxity args = HsTupCon (mkTupConRdrName space boxity arity) boxity arity - where - arity = length args +mkHsTupCon :: NameSpace -> Boxity -> [a] -> HsTupCon +mkHsTupCon space boxity args = HsTupCon boxity (length args) -hsTupParens :: HsTupCon name -> SDoc -> SDoc -hsTupParens (HsTupCon _ b _) p = tupleParens b p +hsTupParens :: HsTupCon -> SDoc -> SDoc +hsTupParens (HsTupCon b _) p = tupleParens b p ----------------------- -- Combine adjacent for-alls. @@ -143,13 +163,18 @@ hsTupParens (HsTupCon _ b _) p = tupleParens b p -- -- A valid type must have one for-all at the top of the type, or of the fn arg types -mkHsForAllTy (Just []) [] ty = ty -- Explicit for-all with no tyvars -mkHsForAllTy mtvs1 [] (HsForAllTy mtvs2 ctxt ty) = mkHsForAllTy (mtvs1 `plus` mtvs2) ctxt ty - where - mtvs1 `plus` Nothing = mtvs1 - Nothing `plus` mtvs2 = mtvs2 - (Just tvs1) `plus` (Just tvs2) = Just (tvs1 ++ tvs2) -mkHsForAllTy tvs ctxt ty = HsForAllTy tvs ctxt ty +mkHsForAllTy mtvs [] ty = mk_forall_ty mtvs ty +mkHsForAllTy mtvs ctxt ty = HsForAllTy mtvs ctxt ty + +-- mk_forall_ty makes a pure for-all type (no context) +mk_forall_ty (Just []) ty = ty -- Explicit for-all with no tyvars +mk_forall_ty mtvs1 (HsParTy ty) = mk_forall_ty mtvs1 ty +mk_forall_ty mtvs1 (HsForAllTy mtvs2 ctxt ty) = mkHsForAllTy (mtvs1 `plus` mtvs2) ctxt ty +mk_forall_ty mtvs1 ty = HsForAllTy mtvs1 [] ty + +mtvs1 `plus` Nothing = mtvs1 +Nothing `plus` mtvs2 = mtvs2 +(Just tvs1) `plus` (Just tvs2) = Just (tvs1 ++ tvs2) mkHsDictTy cls tys = HsPredTy (HsClassP cls tys) mkHsIParamTy v ty = HsPredTy (HsIParam v ty) @@ -172,6 +197,45 @@ replaceTyVarName (IfaceTyVar n k) n' = IfaceTyVar n' k \end{code} +\begin{code} +splitHsInstDeclTy + :: Outputable name + => HsType name + -> ([HsTyVarBndr name], HsContext name, name, [HsType name]) + -- Split up an instance decl type, returning the pieces + +-- In interface files, the instance declaration head is created +-- by HsTypes.toHsType, which does not guarantee to produce a +-- HsForAllTy. For example, if we had the weird decl +-- instance Foo T => Foo [T] +-- then we'd get the instance type +-- Foo T -> Foo [T] +-- So when colleting the instance context, to be on the safe side +-- we gather predicate arguments +-- +-- For source code, the parser ensures the type will have the right shape. +-- (e.g. see ParseUtil.checkInstType) + +splitHsInstDeclTy inst_ty + = case inst_ty of + HsForAllTy (Just tvs) cxt1 tau + -> (tvs, cxt1++cxt2, cls, tys) + where + (cxt2, cls, tys) = split_tau tau + + other -> ([], cxt2, cls, tys) + where + (cxt2, cls, tys) = split_tau inst_ty + + where + split_tau (HsFunTy (HsPredTy p) ty) = (p:ps, cls, tys) + where + (ps, cls, tys) = split_tau ty + split_tau (HsPredTy (HsClassP cls tys)) = ([], cls,tys) + split_tau other = pprPanic "splitHsInstDeclTy" (ppr inst_ty) +\end{code} + + %************************************************************************ %* * \subsection{Pretty printing} @@ -185,6 +249,10 @@ NB: these types get printed into interface files, so 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 @@ -207,76 +275,89 @@ pprHsForAll tvs cxt ptext SLIT("forall") <+> interppSP tvs <> dot <+> -- **! ToDo: want to hide uvars from user, but not enough info -- in a HsTyVarBndr name (see PprType). KSW 2000-10. - (if null cxt then - empty - else - ppr_context cxt <+> ptext SLIT("=>") - ) + 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) -- 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 -maybeParen False p = p + -- Used for LH arg of (->) +pREC_OP = (2 :: Int) -- Used for arg of any infix operator + -- (we don't keep their fixities around) +pREC_CON = (3 :: Int) -- Used for arg of type applicn: + -- always parenthesise unless atomic + +maybeParen :: Int -- Precedence of context + -> Int -- Precedence of top-level operator + -> SDoc -> SDoc -- Wrap in parens if (ctxt >= op) +maybeParen ctxt_prec op_prec p | ctxt_prec >= op_prec = parens p + | otherwise = p -- printing works more-or-less as for Types pprHsType, pprParendHsType :: (Outputable name) => HsType name -> SDoc -pprHsType ty = ppr_mono_ty pREC_TOP ty +pprHsType ty = ppr_mono_ty pREC_TOP (de_paren ty) pprParendHsType ty = ppr_mono_ty pREC_CON ty +-- Remove outermost HsParTy parens before printing a type +de_paren (HsParTy ty) = de_paren ty +de_paren ty = ty + ppr_mono_ty ctxt_prec (HsForAllTy maybe_tvs ctxt ty) - = maybeParen (ctxt_prec >= pREC_FUN) $ + = maybeParen ctxt_prec pREC_FUN $ sep [pp_header, pprHsType ty] where pp_header = case maybe_tvs of Just tvs -> pprHsForAll tvs ctxt Nothing -> pprHsContext ctxt -ppr_mono_ty ctxt_prec (HsTyVar name) - = ppr name - -ppr_mono_ty ctxt_prec (HsFunTy ty1 ty2) - = let p1 = ppr_mono_ty pREC_FUN ty1 - p2 = ppr_mono_ty pREC_TOP ty2 - in - maybeParen (ctxt_prec >= pREC_FUN) - (sep [p1, (<>) (ptext SLIT("-> ")) p2]) - +ppr_mono_ty ctxt_prec (HsTyVar name) = ppr name +ppr_mono_ty ctxt_prec (HsFunTy ty1 ty2) = ppr_fun_ty ctxt_prec ty1 ty2 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) +ppr_mono_ty ctxt_prec (HsPredTy pred) = braces (ppr pred) +ppr_mono_ty ctxt_prec (HsNumTy n) = integer n -- generics only 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]) + = 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 (HsOpTy ty1 HsArrow ty2) + = ppr_fun_ty ctxt_prec ty1 ty2 + +ppr_mono_ty ctxt_prec (HsOpTy ty1 op ty2) + = maybeParen ctxt_prec pREC_OP $ + ppr_mono_ty pREC_OP ty1 <+> ppr op <+> ppr_mono_ty pREC_OP ty2 -ppr_mono_ty ctxt_prec (HsPredTy pred) - = braces (ppr pred) +ppr_mono_ty ctxt_prec (HsParTy ty) + = parens (ppr_mono_ty pREC_TOP ty) + -- Put the parens in where the user did + -- But we still use the precedence stuff to add parens because + -- toHsType doesn't put in any HsParTys, so we may still need them -ppr_mono_ty ctxt_prec (HsUsageTy u ty) - = maybeParen (ctxt_prec >= pREC_CON) - (sep [ptext SLIT("__u") <+> ppr_mono_ty pREC_CON u, - ppr_mono_ty pREC_CON ty]) - -- pREC_FUN would be logical for u, but it yields a reduce/reduce conflict with AppTy +-------------------------- +ppr_fun_ty ctxt_prec ty1 ty2 + = let p1 = ppr_mono_ty pREC_FUN ty1 + p2 = ppr_mono_ty pREC_TOP ty2 + in + maybeParen ctxt_prec pREC_FUN $ + sep [p1, ptext SLIT("->") <+> p2] --- 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 +-------------------------- +pabrackets p = ptext SLIT("[:") <> p <> ptext SLIT(":]") \end{code} @@ -333,10 +414,9 @@ 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' + | isTupleTyCon tc = HsTupleTy (HsTupCon (tupleTyConBoxity tc) (tyConArity tc)) tys' | tc `hasKey` listTyConKey = HsListTy (head tys') - | tc `hasKey` usOnceTyConKey = hsUsOnce_Name -- must print !, . unqualified - | tc `hasKey` usManyTyConKey = hsUsMany_Name -- must print !, . unqualified + | tc `hasKey` parrTyConKey = HsPArrTy (head tys') | otherwise = generic_case where generic_case = foldl HsAppTy (HsTyVar (getName tc)) tys' @@ -348,10 +428,6 @@ toHsType ty@(ForAllTy _ _) = case tcSplitSigmaTy ty of (map toHsPred preds) (toHsType tau) -toHsType (UsageTy u ty) = HsUsageTy (toHsType u) (toHsType ty) - -- **! consider dropping usMany annotations ToDo KSW 2000-10 - - toHsPred (ClassP cls tys) = HsClassP (getName cls) (map toHsType tys) toHsPred (IParam n ty) = HsIParam n (toHsType ty) @@ -444,6 +520,12 @@ eq_hsType env (HsTupleTy c1 tys1) (HsTupleTy c2 tys2) 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 @@ -453,15 +535,16 @@ eq_hsType env (HsFunTy a1 b1) (HsFunTy a2 b2) eq_hsType env (HsPredTy p1) (HsPredTy p2) = eq_hsPred env p1 p2 -eq_hsType env (HsUsageTy u1 ty1) (HsUsageTy u2 ty2) - = eq_hsType env u1 u2 && eq_hsType env ty1 ty2 - 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_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