merge upstream HEAD

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

diff --git a/compiler/types/TypeRep.lhs b/compiler/types/TypeRep.lhs
index fafbaab..1be55d7 100644 (file)
--- a/compiler/types/TypeRep.lhs
+++ b/compiler/types/TypeRep.lhs
@@ -485,9 +485,7 @@ pprKind = pprType
 pprParendKind = pprParendType
 
 ppr_type :: Prec -> Type -> SDoc
-ppr_type _ (TyVarTy tv)                -- Note [Infix type variables]
-  | isSymOcc (getOccName tv)  = parens (ppr tv)
-  | otherwise                = ppr tv
+ppr_type _ (TyVarTy tv)              = ppr_tvar tv
 ppr_type p (PredTy pred)      = maybeParen p TyConPrec $
                                 ifPprDebug (ptext (sLit "<pred>")) <> (ppr pred)
 ppr_type p (TyConApp tc tys)  = ppr_tc_app p tc tys
@@ -503,8 +501,11 @@ ppr_type p (FunTy ty1 ty2)
     maybeParen p FunPrec $
     sep (ppr_type FunPrec ty1 : ppr_fun_tail ty2)
   where
-    ppr_fun_tail (FunTy ty1 ty2) = (arrow <+> ppr_type FunPrec ty1) : ppr_fun_tail ty2
-    ppr_fun_tail other_ty        = [arrow <+> pprType other_ty]
+    ppr_fun_tail (FunTy ty1 ty2) 
+      | not (is_pred ty1) = (arrow <+> ppr_type FunPrec ty1) : ppr_fun_tail ty2
+    ppr_fun_tail other_ty = [arrow <+> pprType other_ty]
+    is_pred (PredTy {}) = True
+    is_pred _           = False
 
 ppr_forall_type :: Prec -> Type -> SDoc
 ppr_forall_type p ty
@@ -540,6 +541,8 @@ ppr_tc_app _ tc [ty]
   | tc `hasKey` argTypeKindTyConKey      = ptext (sLit "??")
 
 ppr_tc_app p tc tys
+  | [ecvar,ty] <- tys, tc `hasKey` hetMetCodeTypeTyConKey
+  = ptext (sLit "<[")  <> pprType ty <> ptext (sLit "]>@") <> ppr ecvar
   | isTupleTyCon tc && tyConArity tc == length tys
   = tupleParens (tupleTyConBoxity tc) (sep (punctuate comma (map pprType tys)))
   | otherwise
@@ -567,21 +570,26 @@ ppr_tc tc
                                             else ptext (sLit "<nt>"))
               | otherwise     = empty
 
+ppr_tvar :: TyVar -> SDoc
+ppr_tvar tv  -- Note [Infix type variables]
+  | isSymOcc (getOccName tv)  = parens (ppr tv)
+  | otherwise                = ppr tv
+
 -------------------
 pprForAll :: [TyVar] -> SDoc
 pprForAll []  = empty
 pprForAll tvs = ptext (sLit "forall") <+> sep (map pprTvBndr tvs) <> dot
 
 pprTvBndr :: TyVar -> SDoc
-pprTvBndr tv | isLiftedTypeKind kind = ppr tv
-            | otherwise             = parens (ppr tv <+> dcolon <+> pprKind kind)
+pprTvBndr tv | isLiftedTypeKind kind = ppr_tvar tv
+            | otherwise             = parens (ppr_tvar tv <+> dcolon <+> pprKind kind)
             where
               kind = tyVarKind tv
 \end{code}
 
 Note [Infix type variables]
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~
-In Haskell 98 you can say
+With TypeOperators you can say
 
    f :: (a ~> b) -> b