X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2FhsSyn%2FHsTypes.lhs;h=f1343a39ef9aa5e7621b1eb176a34b8751afedc9;hb=28a464a75e14cece5db40f2765a29348273ff2d2;hp=a37e27db72e649383ca489033525505242006178;hpb=788faebb40b51d37e73ed94dfc99460d39a1a811;p=ghc-hetmet.git diff --git a/ghc/compiler/hsSyn/HsTypes.lhs b/ghc/compiler/hsSyn/HsTypes.lhs index a37e27d..f1343a3 100644 --- a/ghc/compiler/hsSyn/HsTypes.lhs +++ b/ghc/compiler/hsSyn/HsTypes.lhs @@ -5,105 +5,158 @@ \begin{code} module HsTypes ( - HsType(..), HsTyVarBndr(..), - , HsContext, HsPred(..) - , HsTupCon(..), hsTupParens, mkHsTupCon, - , hsUsOnce, hsUsMany - - , mkHsForAllTy, mkHsDictTy, mkHsIParamTy - , hsTyVarName, hsTyVarNames, replaceTyVarName + HsType(..), LHsType, + HsTyVarBndr(..), LHsTyVarBndr, + HsExplicitForAll(..), + HsContext, LHsContext, + HsPred(..), LHsPred, + + LBangType, BangType, HsBang(..), + getBangType, getBangStrictness, + + mkExplicitHsForAllTy, mkImplicitHsForAllTy, + hsTyVarName, hsTyVarNames, replaceTyVarName, + hsLTyVarName, hsLTyVarNames, hsLTyVarLocName, hsLTyVarLocNames, + splitHsInstDeclTy, splitHsFunType, + + -- Type place holder + PostTcType, placeHolderType, -- Printing - , pprParendHsType, pprHsForAll, pprHsContext, pprHsTyVarBndr - - -- Equality over Hs things - , EqHsEnv, emptyEqHsEnv, extendEqHsEnv, - , eqWithHsTyVars, eq_hsVar, eq_hsVars, eq_hsTyVars, eq_hsType, eq_hsContext, eqListBy - - -- Converting from Type to HsType - , toHsType, toHsTyVar, toHsTyVars, toHsContext, toHsFDs + pprParendHsType, pprHsForAll, pprHsContext, ppr_hs_context, pprHsTyVarBndr ) where #include "HsVersions.h" -import Class ( FunDep ) -import Type ( Type, Kind, ThetaType, PredType(..), - splitSigmaTy, liftedTypeKind - ) -import TypeRep ( Type(..), TyNote(..) ) -- toHsType sees the representation -import TyCon ( isTupleTyCon, tupleTyConBoxity, tyConArity, getSynTyConDefn ) -import RdrName ( RdrName, mkUnqual ) -import Name ( Name, getName ) -import OccName ( NameSpace, tvName ) -import Var ( TyVar, tyVarKind ) -import Subst ( mkTyVarSubst, substTy ) -import PprType ( {- instance Outputable Kind -}, pprParendKind ) -import BasicTypes ( Boxity(..), Arity, tupleParens ) -import PrelNames ( mkTupConRdrName, listTyConKey, usOnceTyConKey, usManyTyConKey, hasKey, - usOnceTyConName, usManyTyConName - ) -import FiniteMap +import {-# SOURCE #-} HsExpr ( HsSplice, pprSplice ) + +import Type ( Type ) +import Kind ( {- instance Outputable Kind -}, Kind, + pprParendKind, pprKind, isLiftedTypeKind ) +import BasicTypes ( IPName, Boxity, tupleParens ) +import SrcLoc ( Located(..), unLoc, noSrcSpan ) +import StaticFlags ( opt_PprStyle_Debug ) 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" \end{code} +%************************************************************************ +%* * +\subsection{Bang annotations} +%* * +%************************************************************************ + +\begin{code} +type LBangType name = Located (BangType name) +type BangType name = HsType name -- Bangs are in the HsType data type + +data HsBang = HsNoBang -- Only used as a return value for getBangStrictness, + -- never appears on a HsBangTy + | HsStrict -- ! + | HsUnbox -- {-# UNPACK #-} ! (GHC extension, meaning "unbox") + +instance Outputable HsBang where + ppr (HsNoBang) = empty + ppr (HsStrict) = char '!' + ppr (HsUnbox) = ptext SLIT("!!") + +getBangType :: LHsType a -> LHsType a +getBangType (L _ (HsBangTy _ ty)) = ty +getBangType ty = ty + +getBangStrictness :: LHsType a -> HsBang +getBangStrictness (L _ (HsBangTy s _)) = s +getBangStrictness _ = HsNoBang +\end{code} + + +%************************************************************************ +%* * +\subsection{Data types} +%* * +%************************************************************************ + This is the syntax for types as seen in type signatures. \begin{code} -type HsContext name = [HsPred name] +type LHsContext name = Located (HsContext name) -data HsPred name = HsClassP name [HsType name] - | HsIParam name (HsType name) +type HsContext name = [LHsPred name] + +type LHsPred name = Located (HsPred name) + +data HsPred name = HsClassP name [LHsType name] + | HsIParam (IPName name) (LHsType name) + +type LHsType name = Located (HsType name) data HsType name - = HsForAllTy (Maybe [HsTyVarBndr name]) -- Nothing for implicitly quantified signatures - (HsContext name) - (HsType name) + = HsForAllTy HsExplicitForAll -- Renamer leaves this flag unchanged, to record the way + -- the user wrote it originally, so that the printer can + -- print it as the user wrote it + [LHsTyVarBndr name] -- With ImplicitForAll, this is the empty list + -- until the renamer fills in the variables + (LHsContext name) + (LHsType name) | HsTyVar name -- Type variable or type constructor - | HsAppTy (HsType name) - (HsType name) + | HsBangTy HsBang (LHsType name) -- Bang-style type annotations - | HsFunTy (HsType name) -- function type - (HsType name) + | HsAppTy (LHsType name) + (LHsType name) - | HsListTy (HsType name) -- Element type + | HsFunTy (LHsType name) -- function type + (LHsType name) - | HsTupleTy (HsTupCon name) - [HsType name] -- Element types (length gives arity) - -- Generics - | HsOpTy (HsType name) name (HsType name) - | HsNumTy Integer - -- these next two are only used in interfaces - | HsPredTy (HsPred name) - - | HsUsageTy (HsType name) -- Usage annotation - (HsType name) -- Annotated type + | HsListTy (LHsType name) -- Element type + | HsPArrTy (LHsType name) -- Elem. type of parallel array: [:t:] ------------------------ -hsUsOnce, hsUsMany :: HsType RdrName -hsUsOnce = HsTyVar (mkUnqual tvName SLIT(".")) -- deep magic -hsUsMany = HsTyVar (mkUnqual tvName SLIT("!")) -- deep magic + | HsTupleTy Boxity + [LHsType name] -- Element types (length gives arity) -hsUsOnce_Name, hsUsMany_Name :: HsType Name -hsUsOnce_Name = HsTyVar usOnceTyConName -hsUsMany_Name = HsTyVar usManyTyConName + | HsOpTy (LHsType name) (Located name) (LHsType name) ------------------------ -data HsTupCon name = HsTupCon name Boxity Arity + | HsParTy (LHsType 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 + + | HsPredTy (HsPred name) -- Only used in the type of an instance + -- declaration, eg. Eq [a] -> Eq a + -- ^^^^ + -- HsPredTy + -- Note no need for location info on the + -- enclosed HsPred; the one on the type will do -instance Eq name => Eq (HsTupCon name) 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 + | HsKindSig (LHsType name) -- (ty :: kind) + Kind -- A type with a kind signature -hsTupParens :: HsTupCon name -> SDoc -> SDoc -hsTupParens (HsTupCon _ b _) p = tupleParens b p + | HsSpliceTy (HsSplice name) + +data HsExplicitForAll = Explicit | Implicit ----------------------- -- Combine adjacent for-alls. @@ -115,32 +168,87 @@ 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 +mkImplicitHsForAllTy ctxt ty = mkHsForAllTy Implicit [] ctxt ty +mkExplicitHsForAllTy tvs ctxt ty = mkHsForAllTy Explicit tvs ctxt ty + +mkHsForAllTy :: HsExplicitForAll -> [LHsTyVarBndr name] -> LHsContext name -> LHsType name -> HsType name +-- Smart constructor for HsForAllTy +mkHsForAllTy exp tvs (L _ []) ty = mk_forall_ty exp tvs ty +mkHsForAllTy exp tvs ctxt ty = HsForAllTy exp tvs ctxt ty + +-- mk_forall_ty makes a pure for-all type (no context) +mk_forall_ty exp tvs (L _ (HsParTy ty)) = mk_forall_ty exp tvs ty +mk_forall_ty exp1 tvs1 (L _ (HsForAllTy exp2 tvs2 ctxt ty)) = mkHsForAllTy (exp1 `plus` exp2) (tvs1 ++ tvs2) ctxt ty +mk_forall_ty exp tvs ty = HsForAllTy exp tvs (L noSrcSpan []) ty + -- Even if tvs is empty, we still make a HsForAll! + -- In the Implicit case, this signals the place to do implicit quantification + -- In the Explicit case, it prevents implicit quantification + -- (see the sigtype production in Parser.y.pp) + -- so that (forall. ty) isn't implicitly quantified + +Implicit `plus` Implicit = Implicit +exp1 `plus` exp2 = Explicit -mkHsDictTy cls tys = HsPredTy (HsClassP cls tys) -mkHsIParamTy v ty = HsPredTy (HsIParam v ty) +type LHsTyVarBndr name = Located (HsTyVarBndr name) data HsTyVarBndr name = UserTyVar name - | IfaceTyVar name Kind - -- *** NOTA BENE *** A "monotype" in a pragma can have + | KindedTyVar name Kind + -- *** NOTA BENE *** A "monotype" in a pragma can have -- for-alls in it, (mostly to do with dictionaries). These -- must be explicitly Kinded. -hsTyVarName (UserTyVar n) = n -hsTyVarName (IfaceTyVar n _) = n +hsTyVarName :: HsTyVarBndr name -> name +hsTyVarName (UserTyVar n) = n +hsTyVarName (KindedTyVar n _) = n +hsLTyVarName :: LHsTyVarBndr name -> name +hsLTyVarName = hsTyVarName . unLoc + +hsTyVarNames :: [HsTyVarBndr name] -> [name] hsTyVarNames tvs = map hsTyVarName tvs +hsLTyVarNames :: [LHsTyVarBndr name] -> [name] +hsLTyVarNames = map hsLTyVarName + +hsLTyVarLocName :: LHsTyVarBndr name -> Located name +hsLTyVarLocName = fmap hsTyVarName + +hsLTyVarLocNames :: [LHsTyVarBndr name] -> [Located name] +hsLTyVarLocNames = map hsLTyVarLocName + replaceTyVarName :: HsTyVarBndr name1 -> name2 -> HsTyVarBndr name2 -replaceTyVarName (UserTyVar n) n' = UserTyVar n' -replaceTyVarName (IfaceTyVar n k) n' = IfaceTyVar n' k +replaceTyVarName (UserTyVar n) n' = UserTyVar n' +replaceTyVarName (KindedTyVar n k) n' = KindedTyVar n' k +\end{code} + + +\begin{code} +splitHsInstDeclTy + :: OutputableBndr name + => HsType name + -> ([LHsTyVarBndr name], HsContext name, name, [LHsType name]) + -- Split up an instance decl type, returning the pieces + +splitHsInstDeclTy inst_ty + = case inst_ty of + HsParTy (L _ ty) -> splitHsInstDeclTy ty + HsForAllTy _ tvs cxt (L _ ty) -> split_tau tvs (unLoc cxt) ty + other -> split_tau [] [] other + -- The type vars should have been computed by now, even if they were implicit + where + split_tau tvs cxt (HsPredTy (HsClassP cls tys)) = (tvs, cxt, cls, tys) + split_tau tvs cxt (HsParTy (L _ ty)) = split_tau tvs cxt ty + +-- Splits HsType into the (init, last) parts +-- Breaks up any parens in the result type: +-- splitHsFunType (a -> (b -> c)) = ([a,b], c) +splitHsFunType :: LHsType name -> ([LHsType name], LHsType name) +splitHsFunType (L l (HsFunTy x y)) = (x:args, res) + where + (args, res) = splitHsFunType y +splitHsFunType (L _ (HsParTy ty)) = splitHsFunType ty +splitHsFunType other = ([], other) \end{code} @@ -154,299 +262,109 @@ NB: these types get printed into interface files, so don't change the printing format lightly \begin{code} -instance (Outputable name) => Outputable (HsType name) where +instance (OutputableBndr name) => Outputable (HsType name) where ppr ty = pprHsType ty instance (Outputable name) => Outputable (HsTyVarBndr name) where - ppr (UserTyVar name) = ppr name - ppr (IfaceTyVar name kind) = pprHsTyVarBndr name kind + ppr (UserTyVar name) = ppr name + ppr (KindedTyVar name kind) = pprHsTyVarBndr name kind -instance Outputable name => Outputable (HsPred name) where - ppr (HsClassP clas tys) = ppr clas <+> hsep (map pprParendHsType tys) - ppr (HsIParam n ty) = hsep [char '?' <> ppr n, text "::", ppr ty] +instance OutputableBndr name => Outputable (HsPred name) where + ppr (HsClassP clas tys) = ppr clas <+> hsep (map (pprParendHsType.unLoc) tys) + ppr (HsIParam n ty) = hsep [ppr n, dcolon, ppr ty] pprHsTyVarBndr :: Outputable name => name -> Kind -> SDoc -pprHsTyVarBndr name kind | kind == liftedTypeKind = ppr name - | otherwise = hsep [ppr name, dcolon, pprParendKind kind] - -pprHsForAll [] [] = empty -pprHsForAll tvs cxt - -- This printer is used for both interface files and - -- printing user types in error messages; and alas the - -- two use slightly different syntax. Ah well. - = getPprStyle $ \ sty -> - if userStyle sty then - 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("=>") - ) - else -- Used in interfaces - ptext SLIT("__forall") <+> interppSP tvs <+> - ppr_context cxt <+> ptext SLIT("=>") - -pprHsContext :: (Outputable name) => HsContext name -> SDoc +pprHsTyVarBndr name kind | isLiftedTypeKind kind = ppr name + | otherwise = hsep [ppr name, dcolon, pprParendKind kind] + +pprHsForAll exp tvs cxt + | show_forall = forall_part <+> pprHsContext (unLoc cxt) + | otherwise = pprHsContext (unLoc cxt) + where + show_forall = opt_PprStyle_Debug + || (not (null tvs) && is_explicit) + is_explicit = case exp of {Explicit -> True; Implicit -> False} + forall_part = ptext SLIT("forall") <+> interppSP tvs <> dot + +pprHsContext :: (OutputableBndr 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, pprParendHsType :: (OutputableBndr name) => HsType name -> SDoc -pprHsType ty = ppr_mono_ty pREC_TOP ty +pprHsType ty = getPprStyle $ \sty -> ppr_mono_ty pREC_TOP (prepare sty ty) pprParendHsType ty = ppr_mono_ty pREC_CON ty -ppr_mono_ty ctxt_prec (HsForAllTy maybe_tvs ctxt ty) - = 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 (HsTupleTy con tys) = hsTupParens con (interpp'SP tys) -ppr_mono_ty ctxt_prec (HsListTy ty) = brackets (ppr_mono_ty pREC_TOP ty) +-- Before printing a type +-- (a) Remove outermost HsParTy parens +-- (b) Drop top-level for-all type variables in user style +-- since they are implicit in Haskell +prepare sty (HsParTy ty) = prepare sty (unLoc ty) +prepare sty ty = ty + +ppr_mono_lty ctxt_prec ty = ppr_mono_ty ctxt_prec (unLoc ty) + +ppr_mono_ty ctxt_prec (HsForAllTy exp tvs ctxt ty) + = maybeParen ctxt_prec pREC_FUN $ + sep [pprHsForAll exp tvs ctxt, ppr_mono_lty pREC_TOP ty] + +-- gaw 2004 +ppr_mono_ty ctxt_prec (HsBangTy b ty) = ppr b <> ppr ty +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) = tupleParens con (interpp'SP tys) +ppr_mono_ty ctxt_prec (HsKindSig ty kind) = parens (ppr_mono_lty pREC_TOP ty <+> dcolon <+> pprKind kind) +ppr_mono_ty ctxt_prec (HsListTy ty) = brackets (ppr_mono_lty pREC_TOP ty) +ppr_mono_ty ctxt_prec (HsPArrTy ty) = pabrackets (ppr_mono_lty 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 (HsSpliceTy s) = pprSplice s 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) - = braces (ppr pred) - -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 - --- 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 -\end{code} - - -%************************************************************************ -%* * -\subsection{Converting from Type to HsType} -%* * -%************************************************************************ - -@toHsType@ converts from a Type to a HsType, making the latter look as -user-friendly as possible. Notably, it uses synonyms where possible, and -expresses overloaded functions using the '=>' context part of a HsForAllTy. - -\begin{code} -toHsTyVar :: TyVar -> HsTyVarBndr Name -toHsTyVar tv = IfaceTyVar (getName tv) (tyVarKind tv) - -toHsTyVars tvs = map toHsTyVar tvs - -toHsType :: Type -> HsType Name --- 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 syn_ty) real_ty) - | syn_matches = toHsType syn_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 == real_ty - - TyConApp syn_tycon tyargs = syn_ty - (tyvars,ty) = getSynTyConDefn syn_tycon - ty_from_syn = substTy (mkTyVarSubst tyvars tyargs) 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 (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) (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 - | otherwise = generic_case - where - generic_case = foldl HsAppTy (HsTyVar (getName tc)) tys' - tys' = map toHsType tys - saturated = length tys == tyConArity tc - -toHsType ty@(ForAllTy _ _) = case splitSigmaTy ty of - (tvs, preds, tau) -> HsForAllTy (Just (map toHsTyVar tvs)) - (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 (getName n) (toHsType ty) - -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] -\end{code} - - -%************************************************************************ -%* * -\subsection{Comparison} -%* * -%************************************************************************ - -\begin{code} -instance Ord a => Eq (HsType a) where - -- The Ord is needed because we keep a - -- finite map of variables to variables - (==) a b = eq_hsType emptyEqHsEnv a b - -instance Ord a => Eq (HsPred a) where - (==) a b = eq_hsPred emptyEqHsEnv a b - -eqWithHsTyVars :: Ord name => - [HsTyVarBndr name] -> [HsTyVarBndr name] - -> (EqHsEnv name -> Bool) -> Bool -eqWithHsTyVars = eq_hsTyVars emptyEqHsEnv -\end{code} - -\begin{code} -type EqHsEnv n = FiniteMap n n --- Tracks the mapping from L-variables to R-variables - -eq_hsVar :: Ord n => EqHsEnv n -> n -> n -> Bool -eq_hsVar env n1 n2 = case lookupFM env n1 of - Just n1 -> n1 == n2 - Nothing -> n1 == n2 - -extendEqHsEnv env n1 n2 - | n1 == n2 = env - | otherwise = addToFM env n1 n2 - -emptyEqHsEnv :: EqHsEnv n -emptyEqHsEnv = emptyFM -\end{code} - -We do define a specialised equality for these \tr{*Type} types; used -in checking interfaces. + = maybeParen ctxt_prec pREC_CON $ + hsep [ppr_mono_lty pREC_FUN fun_ty, ppr_mono_lty pREC_CON arg_ty] + +ppr_mono_ty ctxt_prec (HsOpTy ty1 op ty2) + = maybeParen ctxt_prec pREC_OP $ + ppr_mono_lty pREC_OP ty1 <+> ppr op <+> ppr_mono_lty pREC_OP ty2 + +ppr_mono_ty ctxt_prec (HsParTy ty) + = parens (ppr_mono_lty 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_fun_ty ctxt_prec ty1 ty2 + = let p1 = ppr_mono_lty pREC_FUN ty1 + p2 = ppr_mono_lty pREC_TOP ty2 + in + maybeParen ctxt_prec pREC_FUN $ + sep [p1, ptext SLIT("->") <+> p2] -\begin{code} -------------------- -eq_hsTyVars env [] [] k = k env -eq_hsTyVars env (tv1:tvs1) (tv2:tvs2) k = eq_hsTyVar env tv1 tv2 $ \ env -> - eq_hsTyVars env tvs1 tvs2 k -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 _ _ _ = False - -eq_hsVars env [] [] k = k env -eq_hsVars env (v1:bs1) (v2:bs2) k = eq_hsVars (extendEqHsEnv env v1 v2) bs1 bs2 k -eq_hsVars env _ _ _ = False +-------------------------- +pabrackets p = ptext SLIT("[:") <> p <> ptext SLIT(":]") \end{code} -\begin{code} -------------------- -eq_hsTypes env = eqListBy (eq_hsType env) - -------------------- -eq_hsType env (HsForAllTy tvs1 c1 t1) (HsForAllTy tvs2 c2 t2) - = eq_tvs tvs1 tvs2 $ \env -> - eq_hsContext env c1 c2 && - eq_hsType env t1 t2 - where - eq_tvs Nothing (Just _) k = False - eq_tvs Nothing Nothing k = k env - eq_tvs (Just _) Nothing k = False - eq_tvs (Just tvs1) (Just tvs2) k = eq_hsTyVars env tvs1 tvs2 k - -eq_hsType env (HsTyVar n1) (HsTyVar n2) - = eq_hsVar env n1 n2 - -eq_hsType env (HsTupleTy c1 tys1) (HsTupleTy c2 tys2) - = (c1 == c2) && eq_hsTypes env tys1 tys2 - -eq_hsType env (HsListTy ty1) (HsListTy 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_hsType env (HsFunTy a1 b1) (HsFunTy a2 b2) - = eq_hsType env a1 a2 && eq_hsType env b1 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_hsType env ty1 ty2 = False - - -------------------- -eq_hsContext env a b = eqListBy (eq_hsPred env) a b - -------------------- -eq_hsPred env (HsClassP c1 tys1) (HsClassP c2 tys2) - = c1 == c2 && eq_hsTypes env tys1 tys2 -eq_hsPred env (HsIParam n1 ty1) (HsIParam n2 ty2) - = n1 == n2 && eq_hsType env ty1 ty2 -eq_hsPred env _ _ = 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}