X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Ftypes%2FTypeRep.lhs;h=1660267b4ef0937463a1e988c7eec4bab6651857;hb=0472771eb382f4707c3c793dfab76a48b4c9cbc3;hp=c1670f67bd61be348484370fcbf9ec87d2512033;hpb=388e3356f71daffa62f1d4157e1e07e4c68f218a;p=ghc-hetmet.git

diff --git a/compiler/types/TypeRep.lhs b/compiler/types/TypeRep.lhs
index c1670f6..1660267 100644
--- a/compiler/types/TypeRep.lhs
+++ b/compiler/types/TypeRep.lhs
@@ -20,7 +20,7 @@ module TypeRep (
 	-- Pretty-printing
 	pprType, pprParendType, pprTypeApp,
 	pprTyThing, pprTyThingCategory, 
-	pprPred, pprTheta, pprForAll, pprThetaArrow, pprClassPred,
+	pprPred, pprEqPred, pprTheta, pprForAll, pprThetaArrow, pprClassPred,
 
 	-- Kinds
 	liftedTypeKind, unliftedTypeKind, openTypeKind,
@@ -428,9 +428,12 @@ pprTypeApp tc tys = ppr_type_app TopPrec (getName tc) tys
 pprPred :: PredType -> SDoc
 pprPred (ClassP cls tys) = pprClassPred cls tys
 pprPred (IParam ip ty)   = ppr ip <> dcolon <> pprType ty
-pprPred (EqPred ty1 ty2) = sep [ ppr_type FunPrec ty1
-                               , nest 2 (ptext (sLit "~"))
-                               , ppr_type FunPrec ty2]
+pprPred (EqPred ty1 ty2) = pprEqPred (ty1,ty2)
+
+pprEqPred :: (Type,Type) -> SDoc
+pprEqPred (ty1,ty2) = sep [ ppr_type FunPrec ty1
+                          , nest 2 (ptext (sLit "~"))
+                          , ppr_type FunPrec ty2]
 			       -- Precedence looks like (->) so that we get
 			       --    Maybe a ~ Bool
 			       --    (a->a) ~ Bool
@@ -468,7 +471,8 @@ ppr_type :: Prec -> Type -> SDoc
 ppr_type _ (TyVarTy tv)		-- Note [Infix type variables]
   | isSymOcc (getOccName tv)  = parens (ppr tv)
   | otherwise		      = ppr tv
-ppr_type _ (PredTy pred)      = ifPprDebug (ptext (sLit "<pred>")) <> (ppr pred)
+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
 
 ppr_type p (AppTy t1 t2) = maybeParen p TyConPrec $