compiler/types/Coercion.lhs

@@ -52,11 +52,12 @@ module Coercion (
 	
         -- ** Substitution
         CvSubstEnv, emptyCvSubstEnv, 
- 	CvSubst(..), emptyCvSubst, Coercion.lookupTyVar, lookupCoVar,
+ 	CvSubst(..), emptyCvSubst, mkCvSubst,
+        Coercion.lookupTyVar, lookupCoVar,
 	isEmptyCvSubst, zapCvSubstEnv, getCvInScope,
         substCo, substCos, substCoVar, substCoVars,
         substCoWithTy, substCoWithTys, 
-	cvTvSubst, tvCvSubst, mkCvSubst, zipOpenCvSubst,
+	cvTvSubst, tvCvSubst, zipOpenCvSubst,
         substTy, extendTvSubst, extendCvSubstAndInScope,
 	substTyVarBndr, substCoVarBndr,
 

compiler/types/Type.lhs

@@ -285,7 +285,7 @@ expandTypeSynonyms ty
       = TyConApp tc (map go tys)
     go (LitTy l)       = LitTy l
     go (TyVarTy tv)    = TyVarTy tv
-    go (AppTy t1 t2)   = AppTy (go t1) (go t2)
+    go (AppTy t1 t2)   = mkAppTy (go t1) (go t2)
     go (FunTy t1 t2)   = FunTy (go t1) (go t2)
     go (ForAllTy tv t) = ForAllTy tv (go t)
 \end{code}