%
-% (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)
-
- , mkHsForAllTy
- , getTyVarName, replaceTyVarName
- , pprParendHsType
- , pprContext
- , cmpHsType, cmpContext
+ HsType(..), HsTyVarBndr(..),
+ , HsContext, HsPred(..)
+ , HsTupCon(..), hsTupParens, mkHsTupCon,
+ , hsUsOnce, hsUsMany
+
+ , mkHsForAllTy, mkHsDictTy, mkHsIParamTy
+ , hsTyVarName, hsTyVarNames, replaceTyVarName
+ , getHsInstHead
+
+ -- 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
) where
-IMP_Ubiq()
+#include "HsVersions.h"
-import CmdLineOpts ( opt_PprUserLength )
-import Outputable ( Outputable(..), PprStyle(..), pprQuote, interppSP )
-import Kind ( Kind {- instance Outputable -} )
-import Name ( nameOccName )
-import Pretty
-import Util ( thenCmp, cmpList, isIn, panic# )
+import Class ( FunDep )
+import TcType ( Type, Kind, ThetaType, SourceType(..),
+ tcSplitSigmaTy, liftedTypeKind, eqKind, tcEqType
+ )
+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 Var ( TyVar, tyVarKind )
+import Subst ( substTyWith )
+import PprType ( {- instance Outputable Kind -}, pprParendKind )
+import BasicTypes ( Boxity(..), Arity, IPName, tupleParens )
+import PrelNames ( mkTupConRdrName, listTyConKey, usOnceTyConKey, usManyTyConKey, hasKey,
+ usOnceTyConName, usManyTyConName
+ )
+import FiniteMap
+import Util ( eqListBy, lengthIs )
+import Outputable
\end{code}
-This is the syntax for types as seen in type signatures.
+
+%************************************************************************
+%* *
+\subsection{Annotating the syntax}
+%* *
+%************************************************************************
\begin{code}
-type Context name = [ClassAssertion name]
+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
-type ClassAssertion name = (name, HsType name)
- -- The type is usually a type variable, but it
- -- doesn't have to be when reading interface files
+placeHolderType :: PostTcType -- Used before typechecking
+placeHolderType = panic "Evaluated the place holder for a PostTcType"
+\end{code}
-data HsType name
- = HsPreForAllTy (Context 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.
+%************************************************************************
+%* *
+\subsection{Data types}
+%* *
+%************************************************************************
+
+This is the syntax for types as seen in type signatures.
- | HsForAllTy [HsTyVar name]
- (Context name)
- (HsType name)
+\begin{code}
+type HsContext name = [HsPred name]
+
+data HsPred name = HsClassP name [HsType name]
+ | HsIParam (IPName name) (HsType name)
- | MonoTyVar name -- Type variable
+data HsType name
+ = HsForAllTy (Maybe [HsTyVarBndr name]) -- Nothing for implicitly quantified signatures
+ (HsContext name)
+ (HsType name)
- | MonoTyApp (HsType name)
+ | HsTyVar name -- Type variable or type constructor
+
+ | HsAppTy (HsType name)
(HsType name)
- | 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
+ -- 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
+
+
+-----------------------
+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 HsTupCon name = HsTupCon name Boxity Arity
+
+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
+
+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
+mkHsDictTy cls tys = HsPredTy (HsClassP cls tys)
+mkHsIParamTy v ty = HsPredTy (HsIParam v ty)
+
+data HsTyVarBndr name
= UserTyVar name
| IfaceTyVar 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.
-getTyVarName (UserTyVar n) = n
-getTyVarName (IfaceTyVar n _) = n
+hsTyVarName (UserTyVar n) = n
+hsTyVarName (IfaceTyVar n _) = n
-replaceTyVarName :: HsTyVar name1 -> name2 -> HsTyVar name2
+hsTyVarNames tvs = map hsTyVarName tvs
+
+replaceTyVarName :: HsTyVarBndr name1 -> name2 -> HsTyVarBndr name2
replaceTyVarName (UserTyVar n) n' = UserTyVar n'
replaceTyVarName (IfaceTyVar n k) n' = IfaceTyVar n' k
\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}
%* *
%************************************************************************
-\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 sty ty = pprQuote sty $ \ sty -> pprHsType sty ty
-
-instance (Outputable name) => Outputable (HsTyVar name) where
- ppr sty (UserTyVar name) = ppr sty name
- ppr sty (IfaceTyVar name kind) = pprQuote sty $ \ sty ->
- hsep [ppr sty name, ptext SLIT("::"), ppr sty kind]
-
-ppr_forall sty ctxt_prec [] [] ty
- = ppr_mono_ty sty ctxt_prec ty
-ppr_forall sty ctxt_prec tvs ctxt ty
- = maybeParen (ctxt_prec >= pREC_FUN) $
- sep [ptext SLIT("_forall_"), brackets (interppSP sty tvs),
- pprContext sty ctxt, ptext SLIT("=>"),
- pprHsType sty ty]
-
-pprContext :: (Outputable name) => PprStyle -> (Context name) -> Doc
-pprContext sty [] = empty
-pprContext sty context
- = hsep [braces (hsep (punctuate comma (map ppr_assert context)))]
- where
- ppr_assert (clas, ty) = hsep [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 (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 `eqKind` 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
+pprHsContext [] = empty
+pprHsContext cxt = ppr_context cxt <+> ptext SLIT("=>")
+
+ppr_context [] = empty
+ppr_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 -> Doc -> Doc
+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 -> Doc
+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)
(sep [p1, (<>) (ptext SLIT("-> ")) p2])
-ppr_mono_ty sty ctxt_prec (MonoTupleTy _ tys)
- = parens (sep (punctuate comma (map (ppr sty) tys)))
+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 sty ctxt_prec (MonoListTy _ ty)
- = brackets (ppr_mono_ty sty 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 sty ctxt_prec (MonoTyApp fun_ty 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)
- (hsep [ppr_mono_ty sty pREC_FUN fun_ty, ppr_mono_ty sty pREC_CON arg_ty])
+ (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_mono_ty sty ctxt_prec (MonoDictTy clas ty)
- = hsep [ppr sty clas, ppr_mono_ty sty pREC_CON ty]
+-- 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 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` 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 = tys `lengthIs` tyConArity tc
+
+toHsType ty@(ForAllTy _ _) = case tcSplitSigmaTy 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 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}
%* *
%************************************************************************
+\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}
+-------------------
+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 `eqKind` 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}
\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_hsTypes env = eqListBy (eq_hsType env)
-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_
+-------------------
+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
--- 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 (HsTupleTy c1 tys1) (HsTupleTy c2 tys2)
+ = (c1 == c2) && eq_hsTypes env tys1 tys2
-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 (HsListTy ty1) (HsListTy ty2)
+ = eq_hsType env ty1 ty2
-cmpHsType cmp (MonoTyVar n1) (MonoTyVar n2)
- = cmp n1 n2
+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 (MonoTupleTy _ tys1) (MonoTupleTy _ tys2)
- = cmpList (cmpHsType cmp) tys1 tys2
-cmpHsType cmp (MonoListTy _ ty1) (MonoListTy _ ty2)
- = cmpHsType cmp ty1 ty2
+eq_hsType env (HsFunTy a1 b1) (HsFunTy a2 b2)
+ = eq_hsType env a1 a2 && eq_hsType env b1 b2
-cmpHsType cmp (MonoTyApp fun_ty1 arg_ty1) (MonoTyApp fun_ty2 arg_ty2)
- = cmpHsType cmp fun_ty1 fun_ty2 `thenCmp` cmpHsType cmp arg_ty1 arg_ty2
+eq_hsType env (HsPredTy p1) (HsPredTy p2)
+ = eq_hsPred env p1 p2
-cmpHsType cmp (MonoFunTy a1 b1) (MonoFunTy a2 b2)
- = cmpHsType cmp a1 a2 `thenCmp` cmpHsType cmp b1 b2
+eq_hsType env (HsUsageTy u1 ty1) (HsUsageTy u2 ty2)
+ = eq_hsType env u1 u2 && eq_hsType env ty1 ty2
-cmpHsType cmp (MonoDictTy c1 ty1) (MonoDictTy c2 ty2)
- = cmp c1 c2 `thenCmp` cmpHsType cmp 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
-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 (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
\end{code}