X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2Ftypes%2FType.lhs;h=8271ce32f389168eac64f3219f2002b90aef3ae9;hb=938f825c4c3aac524459a801816db10718dff9de;hp=5b4aa54d9cdc652feddcb83e61162cb769c1d4eb;hpb=72af48cb2073cd6015942bb6cb713039b58b1b4a;p=ghc-hetmet.git diff --git a/ghc/compiler/types/Type.lhs b/ghc/compiler/types/Type.lhs index 5b4aa54..8271ce3 100644 --- a/ghc/compiler/types/Type.lhs +++ b/ghc/compiler/types/Type.lhs @@ -1,11 +1,12 @@ % % (c) The GRASP/AQUA Project, Glasgow University, 1998 % -\section[Type]{Type} +\section[Type]{Type - public interface} \begin{code} module Type ( - Type(..), TyNote(..), UsageAnn(..), -- Representation visible to friends + -- re-exports from TypeRep: + Type, Kind, TyVarSubst, superKind, superBoxity, -- :: SuperKind @@ -17,17 +18,19 @@ module Type ( boxedTypeKind, unboxedTypeKind, openTypeKind, -- Kind :: superKind - mkArrowKind, mkArrowKinds, hasMoreBoxityInfo, + mkArrowKind, mkArrowKinds, -- mentioned below: hasMoreBoxityInfo, funTyCon, + -- exports from this module: + hasMoreBoxityInfo, + mkTyVarTy, mkTyVarTys, getTyVar, getTyVar_maybe, isTyVarTy, mkAppTy, mkAppTys, splitAppTy, splitAppTys, splitAppTy_maybe, mkFunTy, mkFunTys, splitFunTy_maybe, splitFunTys, splitFunTysN, - funResultTy, funArgTy, - zipFunTys, + funResultTy, funArgTy, zipFunTys, mkTyConApp, mkTyConTy, splitTyConApp_maybe, splitAlgTyConApp_maybe, splitAlgTyConApp, @@ -35,7 +38,8 @@ module Type ( mkSynTy, isSynTy, deNoteType, repType, splitNewType_maybe, - mkUsgTy, isUsgTy{- dont use -}, isNotUsgTy, splitUsgTy, unUsgTy, tyUsg, + UsageAnn(..), mkUsgTy, isUsgTy{- dont use -}, isNotUsgTy, splitUsgTy, unUsgTy, tyUsg, + mkUsForAllTy, mkUsForAllTys, splitUsForAllTys, substUsTy, mkForAllTy, mkForAllTys, splitForAllTy_maybe, splitForAllTys, isForAllTy, applyTy, applyTys, mkPiType, @@ -66,231 +70,53 @@ module Type ( #include "HsVersions.h" +-- We import the representation and primitive functions from TypeRep. +-- Many things are reexported, but not the representation! + +import TypeRep + +-- Other imports: + import {-# SOURCE #-} DataCon( DataCon, dataConType ) import {-# SOURCE #-} PprType( pprType ) -- Only called in debug messages import {-# SOURCE #-} Subst ( mkTyVarSubst, substTy ) -- friends: -import Var ( Id, TyVar, IdOrTyVar, UVar, - tyVarKind, tyVarName, isId, idType, setTyVarName, setVarOcc +import Var ( TyVar, IdOrTyVar, UVar, + tyVarKind, tyVarName, setTyVarName, isId, idType, ) import VarEnv import VarSet -import Name ( NamedThing(..), Provenance(..), ExportFlag(..), - mkWiredInTyConName, mkGlobalName, mkLocalName, mkKindOccFS, tcName, - tidyOccName, TidyOccEnv +import Name ( NamedThing(..), mkLocalName, tidyOccName, ) import NameSet import Class ( classTyCon, Class ) -import TyCon ( TyCon, KindCon, - mkFunTyCon, mkKindCon, mkSuperKindCon, - matchesTyCon, isUnboxedTupleTyCon, isUnLiftedTyCon, +import TyCon ( TyCon, + isUnboxedTupleTyCon, isUnLiftedTyCon, isFunTyCon, isDataTyCon, isNewTyCon, isAlgTyCon, isSynTyCon, tyConArity, - tyConKind, tyConDataCons, getSynTyConDefn, + tyConKind, tyConDataCons, getSynTyConDefn, tyConPrimRep, tyConClass_maybe ) -- others -import BasicTypes ( Unused ) -import SrcLoc ( mkBuiltinSrcLoc, noSrcLoc ) -import PrelMods ( pREL_GHC ) +import SrcLoc ( noSrcLoc ) import Maybes ( maybeToBool ) import PrimRep ( PrimRep(..), isFollowableRep ) -import Unique -- quite a few *Keys -import Util ( thenCmp, mapAccumL, seqList, ($!) ) +import Unique ( Uniquable(..) ) +import Util ( mapAccumL, seqList ) import Outputable import UniqSet ( sizeUniqSet ) -- Should come via VarSet \end{code} -%************************************************************************ -%* * -\subsection{Type Classifications} -%* * -%************************************************************************ - -A type is - - *unboxed* iff its representation is other than a pointer - Unboxed types cannot instantiate a type variable. - Unboxed types are always unlifted. - - *lifted* A type is lifted iff it has bottom as an element. - Closures always have lifted types: i.e. any - let-bound identifier in Core must have a lifted - type. Operationally, a lifted object is one that - can be entered. - (NOTE: previously "pointed"). - - *algebraic* A type with one or more constructors, whether declared - with "data" or "newtype". - An algebraic type is one that can be deconstructed - with a case expression. - *NOT* the same as lifted types, because we also - include unboxed tuples in this classification. - - *data* A type declared with "data". Also boxed tuples. - - *primitive* iff it is a built-in type that can't be expressed - in Haskell. - -Currently, all primitive types are unlifted, but that's not necessarily -the case. (E.g. Int could be primitive.) - -Some primitive types are unboxed, such as Int#, whereas some are boxed -but unlifted (such as ByteArray#). The only primitive types that we -classify as algebraic are the unboxed tuples. - -examples of type classifications: - -Type primitive boxed lifted algebraic ------------------------------------------------------------------------------ -Int#, Yes No No No -ByteArray# Yes Yes No No -(# a, b #) Yes No No Yes -( a, b ) No Yes Yes Yes -[a] No Yes Yes Yes - -%************************************************************************ -%* * -\subsection{The data type} -%* * -%************************************************************************ - - -\begin{code} -type SuperKind = Type -type Kind = Type - -type TyVarSubst = TyVarEnv Type - -data Type - = TyVarTy TyVar - - | AppTy - Type -- Function is *not* a TyConApp - Type - - | TyConApp -- Application of a TyCon - TyCon -- *Invariant* saturated appliations of FunTyCon and - -- synonyms have their own constructors, below. - [Type] -- Might not be saturated. - - | FunTy -- Special case of TyConApp: TyConApp FunTyCon [t1,t2] - Type - Type - - | NoteTy -- Saturated application of a type synonym - TyNote - Type -- The expanded version - - | ForAllTy - TyVar - Type -- TypeKind - -data TyNote - = SynNote Type -- The unexpanded version of the type synonym; always a TyConApp - | FTVNote TyVarSet -- The free type variables of the noted expression - | UsgNote UsageAnn -- The usage annotation at this node - -data UsageAnn - = UsOnce -- Used at most once - | UsMany -- Used possibly many times (no info; this annotation can be omitted) - | UsVar UVar -- Annotation is variable (should only happen inside analysis) -\end{code} - %************************************************************************ %* * -\subsection{Kinds} +\subsection{Stuff to do with kinds.} %* * %************************************************************************ -Kinds -~~~~~ -k::K = Type bx - | k -> k - | kv - -kv :: KX is a kind variable - -Type :: BX -> KX - -bx::BX = Boxed - | Unboxed - | AnyBox -- Used *only* for special built-in things - -- like error :: forall (a::*?). String -> a - -- Here, the 'a' can be instantiated to a boxed or - -- unboxed type. - | bv - -bxv :: BX is a boxity variable - -sk = KX -- A kind - | BX -- A boxity - | sk -> sk -- In ptic (BX -> KX) - -\begin{code} -mk_kind_name key str = mkGlobalName key pREL_GHC (mkKindOccFS tcName str) - (LocalDef mkBuiltinSrcLoc NotExported) - -- mk_kind_name is a bit of a hack - -- The LocalDef means that we print the name without - -- a qualifier, which is what we want for these kinds. - -- It's used for both Kinds and Boxities -\end{code} - -Define KX, BX. - -\begin{code} -superKind :: SuperKind -- KX, the type of all kinds -superKindName = mk_kind_name kindConKey SLIT("KX") -superKind = TyConApp (mkSuperKindCon superKindName) [] - -superBoxity :: SuperKind -- BX, the type of all boxities -superBoxityName = mk_kind_name boxityConKey SLIT("BX") -superBoxity = TyConApp (mkSuperKindCon superBoxityName) [] -\end{code} - -Define Boxed, Unboxed, AnyBox - -\begin{code} -boxedKind, unboxedKind, anyBoxKind :: Kind -- Of superkind superBoxity - -boxedConName = mk_kind_name boxedConKey SLIT("*") -boxedKind = TyConApp (mkKindCon boxedConName superBoxity) [] - -unboxedConName = mk_kind_name unboxedConKey SLIT("#") -unboxedKind = TyConApp (mkKindCon unboxedConName superBoxity) [] - -anyBoxConName = mk_kind_name anyBoxConKey SLIT("?") -anyBoxCon = mkKindCon anyBoxConName superBoxity -- A kind of wild card -anyBoxKind = TyConApp anyBoxCon [] -\end{code} - -Define Type - -\begin{code} -typeCon :: KindCon -typeConName = mk_kind_name typeConKey SLIT("Type") -typeCon = mkKindCon typeConName (superBoxity `FunTy` superKind) -\end{code} - -Define (Type Boxed), (Type Unboxed), (Type AnyBox) - -\begin{code} -boxedTypeKind, unboxedTypeKind, openTypeKind :: Kind -boxedTypeKind = TyConApp typeCon [boxedKind] -unboxedTypeKind = TyConApp typeCon [unboxedKind] -openTypeKind = TyConApp typeCon [anyBoxKind] - -mkArrowKind :: Kind -> Kind -> Kind -mkArrowKind k1 k2 = k1 `FunTy` k2 - -mkArrowKinds :: [Kind] -> Kind -> Kind -mkArrowKinds arg_kinds result_kind = foldr mkArrowKind result_kind arg_kinds -\end{code} - \begin{code} hasMoreBoxityInfo :: Kind -> Kind -> Bool hasMoreBoxityInfo k1 k2 @@ -306,21 +132,6 @@ hasMoreBoxityInfo k1 k2 %************************************************************************ %* * -\subsection{Wired-in type constructors -%* * -%************************************************************************ - -We define a few wired-in type constructors here to avoid module knots - -\begin{code} -funTyConName = mkWiredInTyConName funTyConKey pREL_GHC SLIT("(->)") funTyCon -funTyCon = mkFunTyCon funTyConName (mkArrowKinds [boxedTypeKind, boxedTypeKind] boxedTypeKind) -\end{code} - - - -%************************************************************************ -%* * \subsection{Constructor-specific functions} %* * %************************************************************************ @@ -626,10 +437,11 @@ NB: Invariant: if present, usage note is at the very top of the type. This should be carefully preserved. In some parts of the compiler, comments use the _Once Upon a -Polymorphic Type_ (POPL'99) usage of "sigma = usage-annotated type; -tau = un-usage-annotated type"; unfortunately this conflicts with the -rho/tau/theta/sigma usage in the rest of the compiler. -(KSW 1999-04) +Polymorphic Type_ (POPL'99) usage of "rho = generalised +usage-annotated type; sigma = usage-annotated type; tau = +usage-annotated type except on top"; unfortunately this conflicts with +the rho/tau/theta/sigma usage in the rest of the compiler. (KSW +1999-07) \begin{code} mkUsgTy :: UsageAnn -> Type -> Type @@ -646,16 +458,18 @@ isUsgTy :: Type -> Bool #ifndef USMANY isUsgTy _ = True #else -isUsgTy (NoteTy (UsgNote _) _) = True -isUsgTy other = False +isUsgTy (NoteTy (UsgForAll _) ty) = isUsgTy ty +isUsgTy (NoteTy (UsgNote _) _ ) = True +isUsgTy other = False #endif -- The isNotUsgTy function may return a false True if UsManys are omitted; -- in other words, A SSERT( isNotUsgTy ty ) may be useful but -- A SSERT( not (isNotUsg ty) ) is asking for trouble. KSW 1999-04. isNotUsgTy :: Type -> Bool -isNotUsgTy (NoteTy (UsgNote _) _) = False -isNotUsgTy other = True +isNotUsgTy (NoteTy (UsgForAll _) _) = False +isNotUsgTy (NoteTy (UsgNote _) _) = False +isNotUsgTy other = True -- splitUsgTy_maybe is not exported, since it is meaningless if -- UsManys are omitted. It is used in several places in this module, @@ -663,7 +477,8 @@ isNotUsgTy other = True splitUsgTy_maybe :: Type -> Maybe (UsageAnn,Type) splitUsgTy_maybe (NoteTy (UsgNote usg) ty2) = ASSERT( isNotUsgTy ty2 ) Just (usg,ty2) -splitUsgTy_maybe ty = Nothing +splitUsgTy_maybe ty@(NoteTy (UsgForAll _) _) = pprPanic "splitUsgTy_maybe:" $ pprType ty +splitUsgTy_maybe ty = Nothing splitUsgTy :: Type -> (UsageAnn,Type) splitUsgTy ty = case splitUsgTy_maybe ty of @@ -684,8 +499,38 @@ unUsgTy ty = case splitUsgTy_maybe ty of Just (_,ty1) -> ASSERT2( isNotUsgTy ty1, pprType ty ) ty1 Nothing -> ty -\end{code} +mkUsForAllTy :: UVar -> Type -> Type +mkUsForAllTy uv ty = NoteTy (UsgForAll uv) ty + +mkUsForAllTys :: [UVar] -> Type -> Type +mkUsForAllTys uvs ty = foldr (NoteTy . UsgForAll) ty uvs + +splitUsForAllTys :: Type -> ([UVar],Type) +splitUsForAllTys ty = split ty [] + where split (NoteTy (UsgForAll u) ty) uvs = split ty (u:uvs) + split other_ty uvs = (reverse uvs, other_ty) + +substUsTy :: VarEnv UsageAnn -> Type -> Type +-- assumes range is fresh uvars, so no conflicts +substUsTy ve (NoteTy note@(UsgNote (UsVar u)) + ty ) = NoteTy (case lookupVarEnv ve u of + Just ua -> UsgNote ua + Nothing -> note) + (substUsTy ve ty) +substUsTy ve (NoteTy note@(UsgNote _) ty ) = NoteTy note (substUsTy ve ty) +substUsTy ve (NoteTy note@(UsgForAll _) ty ) = NoteTy note (substUsTy ve ty) +substUsTy ve (NoteTy (SynNote ty1) ty2) = NoteTy (SynNote (substUsTy ve ty1)) + (substUsTy ve ty2) +substUsTy ve (NoteTy note@(FTVNote _) ty ) = NoteTy note (substUsTy ve ty) +substUsTy ve ty@(TyVarTy _ ) = ty +substUsTy ve (AppTy ty1 ty2) = AppTy (substUsTy ve ty1) + (substUsTy ve ty2) +substUsTy ve (FunTy ty1 ty2) = FunTy (substUsTy ve ty1) + (substUsTy ve ty2) +substUsTy ve (TyConApp tyc tys) = TyConApp tyc (map (substUsTy ve) tys) +substUsTy ve (ForAllTy yv ty ) = ForAllTy yv (substUsTy ve ty) +\end{code} --------------------------------------------------------------------- @@ -747,11 +592,12 @@ Applying a for-all to its arguments \begin{code} applyTy :: Type -> Type -> Type -applyTy (NoteTy note@(UsgNote _) fun) arg = NoteTy note (applyTy fun arg) -applyTy (NoteTy _ fun) arg = applyTy fun arg -applyTy (ForAllTy tv ty) arg = ASSERT( isNotUsgTy arg ) - substTy (mkTyVarSubst [tv] [arg]) ty -applyTy other arg = panic "applyTy" +applyTy (NoteTy note@(UsgNote _) fun) arg = NoteTy note (applyTy fun arg) +applyTy (NoteTy note@(UsgForAll _) fun) arg = NoteTy note (applyTy fun arg) +applyTy (NoteTy _ fun) arg = applyTy fun arg +applyTy (ForAllTy tv ty) arg = ASSERT( isNotUsgTy arg ) + substTy (mkTyVarSubst [tv] [arg]) ty +applyTy other arg = panic "applyTy" applyTys :: Type -> [Type] -> Type applyTys fun_ty arg_tys @@ -760,30 +606,25 @@ applyTys fun_ty arg_tys (tvs, ty) = split fun_ty arg_tys split fun_ty [] = ([], fun_ty) + split (NoteTy note@(UsgNote _) fun_ty) + args = case split fun_ty args of + (tvs, ty) -> (tvs, NoteTy note ty) + split (NoteTy note@(UsgForAll _) fun_ty) + args = case split fun_ty args of + (tvs, ty) -> (tvs, NoteTy note ty) split (NoteTy _ fun_ty) args = split fun_ty args split (ForAllTy tv fun_ty) (arg:args) = ASSERT2( isNotUsgTy arg, vcat (map pprType arg_tys) $$ text "in application of" <+> pprType fun_ty) case split fun_ty args of (tvs, ty) -> (tv:tvs, ty) split other_ty args = panic "applyTys" - -{- OLD version with bogus usage stuff - - ************* CHECK WITH KEITH ************** - - go env ty [] = substTy (mkVarEnv env) ty - go env (NoteTy note@(UsgNote _) fun) - args = NoteTy note (go env fun args) - go env (NoteTy _ fun) args = go env fun args - go env (ForAllTy tv ty) (arg:args) = go ((tv,arg):env) ty args - go env other args = panic "applyTys" --} \end{code} Note that we allow applications to be of usage-annotated- types, as an extension: we handle them by lifting the annotation outside. The argument, however, must still be unannotated. + %************************************************************************ %* * \subsection{Stuff to do with the source-language types} @@ -873,6 +714,7 @@ tyVarsOfType (TyConApp tycon tys) = tyVarsOfTypes tys tyVarsOfType (NoteTy (FTVNote tvs) ty2) = tvs tyVarsOfType (NoteTy (SynNote ty1) ty2) = tyVarsOfType ty1 tyVarsOfType (NoteTy (UsgNote _) ty) = tyVarsOfType ty +tyVarsOfType (NoteTy (UsgForAll _) ty) = tyVarsOfType ty tyVarsOfType (FunTy arg res) = tyVarsOfType arg `unionVarSet` tyVarsOfType res tyVarsOfType (AppTy fun arg) = tyVarsOfType fun `unionVarSet` tyVarsOfType arg tyVarsOfType (ForAllTy tyvar ty) = tyVarsOfType ty `minusVarSet` unitVarSet tyvar @@ -883,9 +725,10 @@ tyVarsOfTypes tys = foldr (unionVarSet.tyVarsOfType) emptyVarSet tys -- Add a Note with the free tyvars to the top of the type -- (but under a usage if there is one) addFreeTyVars :: Type -> Type -addFreeTyVars (NoteTy note@(UsgNote _) ty) = NoteTy note (addFreeTyVars ty) -addFreeTyVars ty@(NoteTy (FTVNote _) _) = ty -addFreeTyVars ty = NoteTy (FTVNote (tyVarsOfType ty)) ty +addFreeTyVars (NoteTy note@(UsgNote _) ty) = NoteTy note (addFreeTyVars ty) +addFreeTyVars (NoteTy note@(UsgForAll _) ty) = NoteTy note (addFreeTyVars ty) +addFreeTyVars ty@(NoteTy (FTVNote _) _) = ty +addFreeTyVars ty = NoteTy (FTVNote (tyVarsOfType ty)) ty -- Find the free names of a type, including the type constructors and classes it mentions namesOfType :: Type -> NameSet @@ -946,22 +789,23 @@ tidyType env@(tidy_env, subst) ty Just tv' -> TyVarTy tv' go (TyConApp tycon tys) = let args = map go tys in args `seqList` TyConApp tycon args - go (NoteTy note ty) = (NoteTy $! (go_note note)) $! (go ty) - go (AppTy fun arg) = (AppTy $! (go fun)) $! (go arg) - go (FunTy fun arg) = (FunTy $! (go fun)) $! (go arg) - go (ForAllTy tv ty) = ForAllTy tv' $! (tidyType env' ty) - where - (env', tv') = tidyTyVar env tv + go (NoteTy note ty) = (NoteTy SAPPLY (go_note note)) SAPPLY (go ty) + go (AppTy fun arg) = (AppTy SAPPLY (go fun)) SAPPLY (go arg) + go (FunTy fun arg) = (FunTy SAPPLY (go fun)) SAPPLY (go arg) + go (ForAllTy tv ty) = ForAllTy tvp SAPPLY (tidyType envp ty) + where + (envp, tvp) = tidyTyVar env tv - go_note (SynNote ty) = SynNote $! (go ty) + go_note (SynNote ty) = SynNote SAPPLY (go ty) go_note note@(FTVNote ftvs) = note -- No need to tidy the free tyvars go_note note@(UsgNote _) = note -- Usage annotation is already tidy + go_note note@(UsgForAll _) = note -- Uvar binder is already tidy tidyTypes env tys = map (tidyType env) tys \end{code} -@tidyOpenType@ grabs the free type varibles, tidies them +@tidyOpenType@ grabs the free type variables, tidies them and then uses @tidyType@ to work over the type itself \begin{code} @@ -991,9 +835,16 @@ isUnboxedType :: Type -> Bool isUnboxedType ty = not (isFollowableRep (typePrimRep ty)) isUnLiftedType :: Type -> Bool -isUnLiftedType ty = case splitTyConApp_maybe ty of - Just (tc, ty_args) -> isUnLiftedTyCon tc - other -> False + -- isUnLiftedType returns True for forall'd unlifted types: + -- x :: forall a. Int# + -- I found bindings like these were getting floated to the top level. + -- They are pretty bogus types, mind you. It would be better never to + -- construct them + +isUnLiftedType (ForAllTy tv ty) = isUnLiftedType ty +isUnLiftedType (NoteTy _ ty) = isUnLiftedType ty +isUnLiftedType (TyConApp tc _) = isUnLiftedTyCon tc +isUnLiftedType other = False isUnboxedTupleType :: Type -> Bool isUnboxedTupleType ty = case splitTyConApp_maybe ty of @@ -1026,64 +877,6 @@ typePrimRep ty = case splitTyConApp_maybe ty of other -> PtrRep \end{code} -%************************************************************************ -%* * -\subsection{Equality on types} -%* * -%************************************************************************ - -For the moment at least, type comparisons don't work if -there are embedded for-alls. - -\begin{code} -instance Eq Type where - ty1 == ty2 = case ty1 `cmpTy` ty2 of { EQ -> True; other -> False } - -instance Ord Type where - compare ty1 ty2 = cmpTy ty1 ty2 - -cmpTy :: Type -> Type -> Ordering -cmpTy ty1 ty2 - = cmp emptyVarEnv ty1 ty2 - where - -- The "env" maps type variables in ty1 to type variables in ty2 - -- So when comparing for-alls.. (forall tv1 . t1) (forall tv2 . t2) - -- we in effect substitute tv2 for tv1 in t1 before continuing - lookup env tv1 = case lookupVarEnv env tv1 of - Just tv2 -> tv2 - Nothing -> tv1 - - -- Get rid of NoteTy - cmp env (NoteTy _ ty1) ty2 = cmp env ty1 ty2 - cmp env ty1 (NoteTy _ ty2) = cmp env ty1 ty2 - - -- Deal with equal constructors - cmp env (TyVarTy tv1) (TyVarTy tv2) = lookup env tv1 `compare` tv2 - cmp env (AppTy f1 a1) (AppTy f2 a2) = cmp env f1 f2 `thenCmp` cmp env a1 a2 - cmp env (FunTy f1 a1) (FunTy f2 a2) = cmp env f1 f2 `thenCmp` cmp env a1 a2 - cmp env (TyConApp tc1 tys1) (TyConApp tc2 tys2) = (tc1 `compare` tc2) `thenCmp` (cmps env tys1 tys2) - cmp env (ForAllTy tv1 t1) (ForAllTy tv2 t2) = cmp (extendVarEnv env tv1 tv2) t1 t2 - - -- Deal with the rest: TyVarTy < AppTy < FunTy < TyConApp < ForAllTy - cmp env (AppTy _ _) (TyVarTy _) = GT - - cmp env (FunTy _ _) (TyVarTy _) = GT - cmp env (FunTy _ _) (AppTy _ _) = GT - - cmp env (TyConApp _ _) (TyVarTy _) = GT - cmp env (TyConApp _ _) (AppTy _ _) = GT - cmp env (TyConApp _ _) (FunTy _ _) = GT - - cmp env (ForAllTy _ _) other = GT - - cmp env _ _ = LT - - cmps env [] [] = EQ - cmps env (t:ts) [] = GT - cmps env [] (t:ts) = LT - cmps env (t1:t1s) (t2:t2s) = cmp env t1 t2 `thenCmp` cmps env t1s t2s -\end{code} - %************************************************************************ %* *