[project @ 2002-09-19 13:22:07 by simonmar]

[ghc-hetmet.git] / ghc / compiler / coreSyn / Subst.lhs

diff --git a/ghc/compiler/coreSyn/Subst.lhs b/ghc/compiler/coreSyn/Subst.lhs
index ce5d8bc..17586a1 100644 (file)
--- a/ghc/compiler/coreSyn/Subst.lhs
+++ b/ghc/compiler/coreSyn/Subst.lhs
@@ -28,7 +28,7 @@ module Subst (
 
        -- Type stuff
        mkTyVarSubst, mkTopTyVarSubst, 
-       substTyWith, substTy, substTheta,
+       substTyWith, substTy, substTheta, deShadowTy,
 
        -- Expression stuff
        substExpr
@@ -407,6 +407,9 @@ substTy :: Subst -> Type  -> Type
 substTy subst ty | isEmptySubst subst = ty
                 | otherwise          = subst_ty subst ty
 
+deShadowTy :: Type -> Type             -- Remove any shadowing from the type
+deShadowTy ty = subst_ty emptySubst ty
+
 substTheta :: TyVarSubst -> ThetaType -> ThetaType
 substTheta subst theta
   | isEmptySubst subst = theta