Fix scoped type variables for expression type signatures

[ghc-hetmet.git] / compiler / types / Type.lhs

diff --git a/compiler/types/Type.lhs b/compiler/types/Type.lhs
index a7aeeec..7c05b6d 100644 (file)
--- a/compiler/types/Type.lhs
+++ b/compiler/types/Type.lhs
@@ -117,11 +117,12 @@ import PrelNames( openTypeKindTyConKey, unliftedTypeKindTyConKey,
                   ubxTupleKindTyConKey, argTypeKindTyConKey )
 import TyCon   ( TyCon, isRecursiveTyCon, isPrimTyCon,
                  isUnboxedTupleTyCon, isUnLiftedTyCon,
-                 isFunTyCon, isNewTyCon, newTyConRep, newTyConRhs,
+                 isFunTyCon, isNewTyCon, isClosedNewTyCon, 
+                 newTyConRep, newTyConRhs, 
                  isAlgTyCon, tyConArity, isSuperKindTyCon,
                  tcExpandTyCon_maybe, coreExpandTyCon_maybe,
                  tyConKind, PrimRep(..), tyConPrimRep, tyConUnique,
-                  isCoercionTyCon_maybe, isCoercionTyCon
+                  isCoercionTyCon
                )
 
 -- others
@@ -448,7 +449,7 @@ repType looks through
        (b) synonyms
        (c) predicates
        (d) usage annotations
-       (e) all newtypes, including recursive ones
+       (e) all newtypes, including recursive ones, but not newtype families
 It's useful in the back end.
 
 \begin{code}
@@ -457,7 +458,7 @@ repType :: Type -> Type
 repType ty | Just ty' <- coreView ty = repType ty'
 repType (ForAllTy _ ty)  = repType ty
 repType (TyConApp tc tys)
-  | isNewTyCon tc       = -- Recursive newtypes are opaque to coreView
+  | isClosedNewTyCon tc  = -- Recursive newtypes are opaque to coreView
                           -- but we must expand them here.  Sure to
                           -- be saturated because repType is only applied
                           -- to types of kind *
@@ -616,7 +617,7 @@ splitRecNewType_maybe :: Type -> Maybe Type
 -- Only applied to types of kind *, hence the newtype is always saturated
 splitRecNewType_maybe ty | Just ty' <- coreView ty = splitRecNewType_maybe ty'
 splitRecNewType_maybe (TyConApp tc tys)
-  | isNewTyCon tc
+  | isClosedNewTyCon tc
   = ASSERT( tys `lengthIs` tyConArity tc )     -- splitRecNewType_maybe only be applied 
                                                --      to *types* (of kind *)
     ASSERT( isRecursiveTyCon tc )              -- Guaranteed by coreView
@@ -1027,9 +1028,13 @@ cmpPredX env (IParam n1 ty1) (IParam n2 ty2) = (n1 `compare` n2) `thenCmp` cmpTy
        -- This comparison is used exclusively (I think) for the
        -- finite map built in TcSimplify
 cmpPredX env (ClassP c1 tys1) (ClassP c2 tys2) = (c1 `compare` c2) `thenCmp` cmpTypesX env tys1 tys2
-cmpPredX env (IParam _ _)     (ClassP _ _)     = LT
-cmpPredX env (ClassP _ _)     (IParam _ _)     = GT
 cmpPredX env (EqPred ty1 ty2) (EqPred ty1' ty2') = (cmpTypeX env ty1 ty1') `thenCmp` (cmpTypeX env ty2 ty2')
+
+-- Constructor order: IParam < ClassP < EqPred
+cmpPredX env (IParam {})     _             = LT
+cmpPredX env (ClassP {})    (IParam {})     = GT
+cmpPredX env (ClassP {})    (EqPred {})     = LT
+cmpPredX env (EqPred {})    _              = GT
 \end{code}
 
 PredTypes are used as a FM key in TcSimplify, 
@@ -1429,7 +1434,7 @@ isKind k = isSuperKind (typeKind k)
 
 isSubKind :: Kind -> Kind -> Bool
 -- (k1 `isSubKind` k2) checks that k1 <: k2
-isSubKind (TyConApp kc1 []) (TyConApp kc2 []) = kc1 `isSubKindCon` kc1
+isSubKind (TyConApp kc1 []) (TyConApp kc2 []) = kc1 `isSubKindCon` kc2
 isSubKind (FunTy a1 r1) (FunTy a2 r2)        = (a2 `isSubKind` a1) && (r1 `isSubKind` r2)
 isSubKind (PredTy (EqPred ty1 ty2)) (PredTy (EqPred ty1' ty2')) 
   = ty1 `tcEqType` ty1' && ty2 `tcEqType` ty2'