X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Ftypes%2FType.lhs;h=fd817956d23356001bbb09a08291ae30696a8a14;hb=ff5ae6ab8ed907dcf6adc810791b756bab827ab3;hp=cdc54a1b7afc90ab144842d570600fccaffd9086;hpb=380512de6eef0cbb17431d9e64007a9320914e23;p=ghc-hetmet.git

diff --git a/compiler/types/Type.lhs b/compiler/types/Type.lhs
index cdc54a1..fd81795 100644
--- a/compiler/types/Type.lhs
+++ b/compiler/types/Type.lhs
@@ -55,7 +55,7 @@ module Type (
 
 	-- Source types
 	predTypeRep, mkPredTy, mkPredTys,
-	tyConOrigHead,
+	tyConOrigHead, pprSourceTyCon,
 
 	-- Newtypes
 	splitRecNewType_maybe, newTyConInstRhs,
@@ -92,10 +92,10 @@ module Type (
 
 	-- Performing substitution on types
 	substTy, substTys, substTyWith, substTheta, 
-	substPred, substTyVar, substTyVarBndr, deShadowTy, lookupTyVar,
+	substPred, substTyVar, substTyVars, substTyVarBndr, deShadowTy, lookupTyVar,
 
 	-- Pretty-printing
-	pprType, pprParendType, pprTyThingCategory, pprForAll,
+	pprType, pprParendType, pprTypeApp, pprTyThingCategory, pprForAll,
 	pprPred, pprTheta, pprThetaArrow, pprClassPred, pprKind, pprParendKind
     ) where
 
@@ -411,7 +411,6 @@ splitNewTyConApp_maybe other	      = Nothing
 newTyConInstRhs :: TyCon -> [Type] -> Type
 newTyConInstRhs tycon tys =
     let (tvs, ty) = newTyConRhs tycon in substTyWith tvs tys ty
-
 \end{code}
 
 
@@ -610,6 +609,16 @@ tyConOrigHead :: TyCon -> (TyCon, [Type])
 tyConOrigHead tycon = case tyConFamInst_maybe tycon of
 		        Nothing      -> (tycon, mkTyVarTys (tyConTyVars tycon))
 			Just famInst -> famInst
+
+-- Pretty prints a tycon, using the family instance in case of a
+-- representation tycon.  For example
+--  	e.g.  data T [a] = ...
+-- In that case we want to print `T [a]', where T is the family TyCon
+pprSourceTyCon tycon 
+  | Just (repTyCon, tys) <- tyConFamInst_maybe tycon
+  = ppr $ repTyCon `TyConApp` tys	       -- can't be FunTyCon
+  | otherwise
+  = ppr tycon
 \end{code}
 
 
@@ -1313,6 +1322,9 @@ substTyVar subst@(TvSubst in_scope env) tv
        	Just ty -> ty	-- See Note [Apply Once]
     } 
 
+substTyVars :: TvSubst -> [TyVar] -> [Type]
+substTyVars subst tvs = map (substTyVar subst) tvs
+
 lookupTyVar :: TvSubst -> TyVar  -> Maybe Type
 	-- See Note [Extending the TvSubst]
 lookupTyVar (TvSubst in_scope env) tv = lookupVarEnv env tv