X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2FhsSyn%2FHsTypes.lhs;h=507acce8574fad32033bb2c1d7807210a803ba44;hb=91ef36b9f74a61c0fb0047f3261ce49ed3026e93;hp=e558d4dd46534f26bc97b8aa155619d724af18e4;hpb=7a3bd641457666e10d0a47be9f22762e03defbf0;p=ghc-hetmet.git diff --git a/ghc/compiler/hsSyn/HsTypes.lhs b/ghc/compiler/hsSyn/HsTypes.lhs index e558d4d..507acce 100644 --- a/ghc/compiler/hsSyn/HsTypes.lhs +++ b/ghc/compiler/hsSyn/HsTypes.lhs @@ -1,82 +1,129 @@ % -% (c) The GRASP/AQUA Project, Glasgow University, 1992-1996 +% (c) The GRASP/AQUA Project, Glasgow University, 1992-1998 % \section[HsTypes]{Abstract syntax: user-defined types} -If compiled without \tr{#define COMPILING_GHC}, you get -(part of) a Haskell-abstract-syntax library. With it, -you get part of GHC. - \begin{code} -#include "HsVersions.h" - module HsTypes ( - HsType(..), HsTyVar(..), - SYN_IE(Context), SYN_IE(ClassAssertion) + HsType(..), HsUsageAnn(..), HsTyVarBndr(..), + , HsContext, HsPred(..) + , HsTupCon(..), hsTupParens, mkHsTupCon, - , mkHsForAllTy + , mkHsForAllTy, mkHsUsForAllTy, mkHsDictTy, mkHsIParamTy , getTyVarName, replaceTyVarName - , pprParendHsType - , pprContext - , cmpHsType, cmpContext + + -- Printing + , pprParendHsType, pprHsForAll, pprHsContext, pprHsTyVarBndr + + -- Equality over Hs things + , EqHsEnv, emptyEqHsEnv, extendEqHsEnv, + , eqWithHsTyVars, eq_hsVar, eq_hsVars, eq_hsType, eq_hsContext, eqListBy + + -- Converting from Type to HsType + , toHsType, toHsTyVar, toHsTyVars, toHsContext, toHsFDs ) where -IMP_Ubiq() +#include "HsVersions.h" -import Outputable ( interppSP, ifnotPprForUser ) -import Kind ( Kind {- instance Outputable -} ) -import Pretty -import Util ( thenCmp, cmpList, isIn, panic# ) +import Class ( FunDep ) +import Type ( Type, Kind, PredType(..), UsageAnn(..), ClassContext, + getTyVar_maybe, splitFunTy_maybe, splitAppTy_maybe, + splitTyConApp_maybe, splitPredTy_maybe, + splitUsgTy, splitSigmaTy, unUsgTy, boxedTypeKind + ) +import TypeRep ( Type(..), TyNote(..) ) -- toHsType sees the representation +import TyCon ( isTupleTyCon, tupleTyConBoxity, tyConArity, tyConClass_maybe ) +import PrelInfo ( mkTupConRdrName ) +import RdrName ( RdrName ) +import Name ( toRdrName ) +import OccName ( NameSpace ) +import Var ( TyVar, tyVarKind ) +import PprType ( {- instance Outputable Kind -}, pprParendKind ) +import BasicTypes ( Arity, Boxity(..), tupleParens ) +import Unique ( hasKey, listTyConKey, Uniquable(..) ) +import Maybes ( maybeToBool ) +import FiniteMap +import Outputable \end{code} This is the syntax for types as seen in type signatures. \begin{code} -type Context name = [ClassAssertion name] +type HsContext name = [HsPred name] -type ClassAssertion name = (name, HsType name) - -- The type is usually a type variable, but it - -- doesn't have to be when reading interface files +data HsPred name = HsPClass name [HsType name] + | HsPIParam name (HsType name) data HsType name - = HsPreForAllTy (Context name) - (HsType name) + = HsForAllTy (Maybe [HsTyVarBndr name]) -- Nothing for implicitly quantified signatures + (HsContext name) + (HsType name) - -- The renamer turns HsPreForAllTys into HsForAllTys when they - -- occur in signatures, to make the binding of variables - -- explicit. This distinction is made visible for - -- non-COMPILING_GHC code, because you probably want to do the - -- same thing. + | HsTyVar name -- Type variable - | HsForAllTy [HsTyVar name] - (Context name) + | HsAppTy (HsType name) (HsType name) - | MonoTyVar name -- Type variable - - | MonoTyApp name -- Type constructor or variable - [HsType name] - - -- We *could* have a "MonoTyCon name" equiv to "MonoTyApp name []" - -- (for efficiency, what?) WDP 96/02/18 - - | MonoFunTy (HsType name) -- function type + | HsFunTy (HsType name) -- function type (HsType name) - | MonoListTy name -- The list TyCon name - (HsType name) -- Element type + | HsListTy (HsType name) -- Element type - | MonoTupleTy name -- The tuple TyCon name + | HsTupleTy (HsTupCon name) [HsType name] -- Element types (length gives arity) - -- these next two are only used in unfoldings in interfaces - | MonoDictTy name -- Class - (HsType name) - -mkHsForAllTy [] [] ty = ty + -- these next two are only used in interfaces + | HsPredTy (HsPred name) + + | HsUsgTy (HsUsageAnn name) + (HsType name) + + | HsUsgForAllTy name + (HsType name) + +data HsUsageAnn name + = HsUsOnce + | HsUsMany + | HsUsVar name + + +----------------------- +data HsTupCon name = HsTupCon name Boxity + +instance Eq name => Eq (HsTupCon name) where + (HsTupCon _ b1) == (HsTupCon _ b2) = b1==b2 + +mkHsTupCon :: NameSpace -> Boxity -> [a] -> HsTupCon RdrName +mkHsTupCon space boxity args = HsTupCon (mkTupConRdrName space boxity (length args)) boxity + +hsTupParens :: HsTupCon name -> SDoc -> SDoc +hsTupParens (HsTupCon _ b) p = tupleParens b p + +----------------------- +-- Combine adjacent for-alls. +-- The following awkward situation can happen otherwise: +-- f :: forall a. ((Num a) => Int) +-- might generate HsForAll (Just [a]) [] (HsForAll Nothing [Num a] t) +-- Then a isn't discovered as ambiguous, and we abstract the AbsBinds wrt [] +-- but the export list abstracts f wrt [a]. Disaster. +-- +-- 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 -data HsTyVar name +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) + +data HsTyVarBndr name = UserTyVar name | IfaceTyVar name Kind -- *** NOTA BENE *** A "monotype" in a pragma can have @@ -86,7 +133,7 @@ data HsTyVar name getTyVarName (UserTyVar n) = n getTyVarName (IfaceTyVar n _) = n -replaceTyVarName :: HsTyVar name1 -> name2 -> HsTyVar name2 +replaceTyVarName :: HsTyVarBndr name1 -> name2 -> HsTyVarBndr name2 replaceTyVarName (UserTyVar n) n' = UserTyVar n' replaceTyVarName (IfaceTyVar n k) n' = IfaceTyVar n' k \end{code} @@ -98,29 +145,48 @@ replaceTyVarName (IfaceTyVar n k) n' = IfaceTyVar n' k %* * %************************************************************************ -\begin{code} +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 - ppr = pprHsType - -instance (Outputable name) => Outputable (HsTyVar name) where - ppr sty (UserTyVar name) = ppr sty name - ppr sty (IfaceTyVar name kind) = ppCat [ppr sty name, ppStr "::", ppr sty kind] - - -ppr_forall sty ctxt_prec [] [] ty - = ppr_mono_ty sty ctxt_prec ty -ppr_forall sty ctxt_prec tvs ctxt ty - = ppSep [ppStr "_forall_", ppBracket (interppSP sty tvs), - pprContext sty ctxt, ppStr "=>", - pprHsType sty ty] - -pprContext :: (Outputable name) => PprStyle -> (Context name) -> Pretty -pprContext sty [] = ppNil -pprContext sty context - = ppCat [ppCurlies (ppIntersperse pp'SP (map ppr_assert context))] - where - ppr_assert (clas, ty) = ppCat [ppr sty clas, ppr sty ty] + ppr ty = pprHsType ty + +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] + +pprHsTyVarBndr :: Outputable name => name -> Kind -> SDoc +pprHsTyVarBndr name kind | kind == boxedTypeKind = 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 <+> + (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 +pprHsContext [] = empty +pprHsContext cxt = ppr_context cxt <+> ptext SLIT("=>") + +ppr_context [] = empty +ppr_context cxt = parens (interpp'SP cxt) \end{code} \begin{code} @@ -128,46 +194,132 @@ pREC_TOP = (0 :: Int) pREC_FUN = (1 :: Int) pREC_CON = (2 :: Int) -maybeParen :: Bool -> Pretty -> Pretty -maybeParen True p = ppParens p +maybeParen :: Bool -> SDoc -> SDoc +maybeParen True p = parens p maybeParen False p = p -- printing works more-or-less as for Types -pprHsType, pprParendHsType :: (Outputable name) => PprStyle -> HsType name -> Pretty +pprHsType, pprParendHsType :: (Outputable name) => HsType name -> SDoc -pprHsType sty ty = ppr_mono_ty sty pREC_TOP ty -pprParendHsType sty ty = ppr_mono_ty sty pREC_CON ty +pprHsType ty = ppr_mono_ty pREC_TOP ty +pprParendHsType ty = ppr_mono_ty pREC_CON ty -ppr_mono_ty sty ctxt_prec (HsPreForAllTy ctxt ty) = ppr_forall sty ctxt_prec [] ctxt ty -ppr_mono_ty sty ctxt_prec (HsForAllTy tvs ctxt ty) = ppr_forall sty ctxt_prec tvs ctxt 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 sty ctxt_prec (MonoTyVar name) = ppr sty name +ppr_mono_ty ctxt_prec (HsTyVar name) + = ppr name -ppr_mono_ty sty ctxt_prec (MonoFunTy ty1 ty2) - = let p1 = ppr_mono_ty sty pREC_FUN ty1 - p2 = ppr_mono_ty sty pREC_TOP ty2 +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) - (ppSep [p1, ppBeside (ppStr "-> ") p2]) + (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) + +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) + +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 + + split uvs (HsUsgForAllTy uv ty') = split (uv:uvs) ty' + split uvs ty' = (reverse uvs,ty') + +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 +\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 RdrName +toHsTyVar tv = IfaceTyVar (toRdrName tv) (tyVarKind tv) + +toHsTyVars tvs = map toHsTyVar tvs + +toHsType :: Type -> HsType RdrName +toHsType ty = toHsType' (unUsgTy ty) + -- For now we just discard the usage +-- = case splitUsgTy ty of +-- (usg, tau) -> HsUsgTy (toHsUsg usg) (toHsType' tau) + +toHsType' :: Type -> HsType RdrName +-- Called after the usage is stripped off +-- This function knows the representation of types +toHsType' (TyVarTy tv) = HsTyVar (toRdrName 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' ty@(TyConApp tc tys) -- Must be saturated because toHsType's arg is of kind * + | not saturated = generic_case + | isTupleTyCon tc = HsTupleTy (HsTupCon (toRdrName tc) (tupleTyConBoxity tc)) tys' + | tc `hasKey` listTyConKey = HsListTy (head tys') + | maybeToBool maybe_class = HsPredTy (HsPClass (toRdrName clas) tys') + | otherwise = generic_case + where + generic_case = foldl HsAppTy (HsTyVar (toRdrName tc)) tys' + maybe_class = tyConClass_maybe tc + Just clas = maybe_class + tys' = map toHsType tys + saturated = length tys == tyConArity tc -ppr_mono_ty sty ctxt_prec (MonoTupleTy _ tys) - = ppParens (ppInterleave ppComma (map (ppr sty) tys)) +toHsType' ty@(ForAllTy _ _) = case splitSigmaTy ty of + (tvs, preds, tau) -> HsForAllTy (Just (map toHsTyVar tvs)) + (map toHsPred preds) + (toHsType tau) -ppr_mono_ty sty ctxt_prec (MonoListTy _ ty) - = ppBesides [ppLbrack, ppr_mono_ty sty pREC_TOP ty, ppRbrack] -ppr_mono_ty sty ctxt_prec (MonoTyApp tycon tys) - = let pp_tycon = ppr sty tycon in - if null tys then - pp_tycon - else - maybeParen (ctxt_prec >= pREC_CON) - (ppCat [pp_tycon, ppInterleave ppNil (map (ppr_mono_ty sty pREC_CON) tys)]) +toHsPred (Class cls tys) = HsPClass (toRdrName cls) (map toHsType tys) +toHsPred (IParam n ty) = HsPIParam (toRdrName n) (toHsType ty) -ppr_mono_ty sty ctxt_prec (MonoDictTy clas ty) - = ppCurlies (ppCat [ppr sty clas, ppr_mono_ty sty pREC_CON ty]) - -- Curlies are temporary +toHsContext :: ClassContext -> HsContext RdrName +toHsContext cxt = [HsPClass (toRdrName cls) (map toHsType tys) | (cls,tys) <- cxt] + +toHsUsg UsOnce = HsUsOnce +toHsUsg UsMany = HsUsMany +toHsUsg (UsVar v) = HsUsVar (toRdrName v) + +toHsFDs :: [FunDep TyVar] -> [FunDep RdrName] +toHsFDs fds = [(map toRdrName ns, map toRdrName ms) | (ns,ms) <- fds] \end{code} @@ -177,69 +329,115 @@ ppr_mono_ty sty ctxt_prec (MonoDictTy clas ty) %* * %************************************************************************ +\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. Most any other use is likely to be {\em -wrong}, so be careful! +in checking interfaces. \begin{code} -cmpHsTyVar :: (a -> a -> TAG_) -> HsTyVar a -> HsTyVar a -> TAG_ -cmpHsType :: (a -> a -> TAG_) -> HsType a -> HsType a -> TAG_ -cmpContext :: (a -> a -> TAG_) -> Context a -> Context a -> TAG_ +------------------- +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 +\end{code} -cmpHsTyVar cmp (UserTyVar v1) (UserTyVar v2) = v1 `cmp` v2 -cmpHsTyVar cmp (IfaceTyVar v1 _) (IfaceTyVar v2 _) = v1 `cmp` v2 -cmpHsTyVar cmp (UserTyVar _) other = LT_ -cmpHsTyVar cmp other1 other2 = GT_ +\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 --- We assume that HsPreForAllTys have been smashed by now. -# ifdef DEBUG -cmpHsType _ (HsPreForAllTy _ _) _ = panic# "cmpHsType:HsPreForAllTy:1st arg" -cmpHsType _ _ (HsPreForAllTy _ _) = panic# "cmpHsType:HsPreForAllTy:2nd arg" -# endif +eq_hsType env (HsTyVar n1) (HsTyVar n2) + = eq_hsVar env n1 n2 -cmpHsType cmp (HsForAllTy tvs1 c1 t1) (HsForAllTy tvs2 c2 t2) - = cmpList (cmpHsTyVar cmp) tvs1 tvs2 `thenCmp` - cmpContext cmp c1 c2 `thenCmp` - cmpHsType cmp t1 t2 +eq_hsType env (HsTupleTy c1 tys1) (HsTupleTy c2 tys2) + = (c1 == c2) && eq_hsTypes env tys1 tys2 -cmpHsType cmp (MonoTyVar n1) (MonoTyVar n2) - = cmp n1 n2 +eq_hsType env (HsListTy ty1) (HsListTy ty2) + = eq_hsType env ty1 ty2 -cmpHsType cmp (MonoTupleTy _ tys1) (MonoTupleTy _ tys2) - = cmpList (cmpHsType cmp) tys1 tys2 -cmpHsType cmp (MonoListTy _ ty1) (MonoListTy _ ty2) - = cmpHsType cmp 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 -cmpHsType cmp (MonoTyApp tc1 tys1) (MonoTyApp tc2 tys2) - = cmp tc1 tc2 `thenCmp` - cmpList (cmpHsType cmp) tys1 tys2 +eq_hsType env (HsFunTy a1 b1) (HsFunTy a2 b2) + = eq_hsType env a1 a2 && eq_hsType env b1 b2 -cmpHsType cmp (MonoFunTy a1 b1) (MonoFunTy a2 b2) - = cmpHsType cmp a1 a2 `thenCmp` cmpHsType cmp b1 b2 +eq_hsType env (HsPredTy p1) (HsPredTy p2) + = eq_hsPred env p1 p2 -cmpHsType cmp (MonoDictTy c1 ty1) (MonoDictTy c2 ty2) - = cmp c1 c2 `thenCmp` cmpHsType cmp ty1 ty2 +eq_hsType env (HsUsgTy u1 ty1) (HsUsgTy u2 ty2) + = eqUsg u1 u2 && eq_hsType env ty1 ty2 + +eq_hsType env ty1 ty2 = False -cmpHsType cmp ty1 ty2 -- tags must be different - = let tag1 = tag ty1 - tag2 = tag ty2 - in - if tag1 _LT_ tag2 then LT_ else GT_ - where - tag (MonoTyVar n1) = (ILIT(1) :: FAST_INT) - tag (MonoTupleTy _ tys1) = ILIT(2) - tag (MonoListTy _ ty1) = ILIT(3) - tag (MonoTyApp tc1 tys1) = ILIT(4) - tag (MonoFunTy a1 b1) = ILIT(5) - tag (MonoDictTy c1 ty1) = ILIT(7) - tag (HsForAllTy _ _ _) = ILIT(8) - tag (HsPreForAllTy _ _) = ILIT(9) ------------------- -cmpContext cmp a b - = cmpList cmp_ctxt a b - where - cmp_ctxt (c1, ty1) (c2, ty2) - = cmp c1 c2 `thenCmp` cmpHsType cmp ty1 ty2 +eq_hsContext env a b = eqListBy (eq_hsPred env) a b + +------------------- +eq_hsPred env (HsPClass c1 tys1) (HsPClass c2 tys2) + = c1 == c2 && eq_hsTypes env tys1 tys2 +eq_hsPred env (HsPIParam n1 ty1) (HsPIParam 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}