[project @ 2005-11-23 12:27:43 by simonmar]

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

diff --git a/ghc/compiler/types/Type.lhs b/ghc/compiler/types/Type.lhs
index 5a4fbb0..f4279a4 100644 (file)
--- a/ghc/compiler/types/Type.lhs
+++ b/ghc/compiler/types/Type.lhs
@@ -423,13 +423,23 @@ It's useful in the back end.
 \begin{code}
 repType :: Type -> Type
 -- Only applied to types of kind *; hence tycons are saturated
-repType (ForAllTy _ ty)   = repType ty
-repType (NoteTy   _ ty)   = repType ty
-repType (PredTy  p)       = repType (predTypeRep p)
-repType (TyConApp tc tys) 
-  | isNewTyCon tc        = ASSERT( tys `lengthIs` tyConArity tc )
-                           repType (new_type_rep tc tys)
-repType ty               = ty
+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
+                          -- but we must expand them here.  Sure to
+                          -- be saturated because repType is only applied
+                          -- to types of kind *
+                          ASSERT( isRecursiveTyCon tc && 
+                                  tys `lengthIs` tyConArity tc )
+                          repType (new_type_rep tc tys)
+repType ty = ty
+
+-- new_type_rep doesn't ask any questions: 
+-- it just expands newtype, whether recursive or not
+new_type_rep new_tycon tys = ASSERT( tys `lengthIs` tyConArity new_tycon )
+                            case newTyConRep new_tycon of
+                                (tvs, rep_ty) -> substTyWith tvs tys rep_ty
 
 -- ToDo: this could be moved to the code generator, using splitTyConApp instead
 -- of inspecting the type directly.
@@ -446,11 +456,6 @@ typePrimRep ty = case repType ty of
        -- (we claim) there is no way to constrain f's kind any other
        -- way.
 
--- new_type_rep doesn't ask any questions: 
--- it just expands newtype, whether recursive or not
-new_type_rep new_tycon tys = ASSERT( tys `lengthIs` tyConArity new_tycon )
-                            case newTyConRep new_tycon of
-                                (tvs, rep_ty) -> substTyWith tvs tys rep_ty
 \end{code}