Remove unused constructors AvoidMe, WildCard

diff --git a/compiler/types/Unify.lhs b/compiler/types/Unify.lhs
index c1ef798..3e35ac6 100644 (file)
--- a/compiler/types/Unify.lhs
+++ b/compiler/types/Unify.lhs
@@ -656,15 +656,6 @@ uUnrefined subst tv1 ty2 (TyVarTy tv2)
        ; b2 <- tvBindFlag tv2
        ; case (b1,b2) of
            (BindMe, _)          -> bind tv1 ty2
-
-           (AvoidMe, BindMe)    -> bind tv2 ty1
-           (AvoidMe, _)         -> bind tv1 ty2
-
-           (WildCard, WildCard) -> return subst
-           (WildCard, Skolem)   -> return subst
-           (WildCard, _)        -> bind tv2 ty1
-
-           (Skolem, WildCard)   -> return subst
            (Skolem, Skolem)     -> failWith (misMatch ty1 ty2)
            (Skolem, _)          -> bind tv2 ty1
        }
@@ -704,29 +695,33 @@ bindTv :: TvSubstEnv -> TyVar -> Type -> UM TvSubstEnv
 bindTv subst tv ty     -- ty is not a type variable
   = do  { b <- tvBindFlag tv
        ; case b of
-           Skolem   -> failWith (misMatch (TyVarTy tv) ty)
-           WildCard -> return subst
-           _other   -> return $ extendVarEnv subst tv ty
+           Skolem -> failWith (misMatch (TyVarTy tv) ty)
+           BindMe -> return $ extendVarEnv subst tv ty
        }
 \end{code}
 
 %************************************************************************
 %*                                                                     *
-               Unification monad
+               Binding decisions
 %*                                                                     *
 %************************************************************************
 
 \begin{code}
 data BindFlag 
   = BindMe     -- A regular type variable
-  | AvoidMe    -- Like BindMe but, given the choice, avoid binding it
 
   | Skolem     -- This type variable is a skolem constant
                -- Don't bind it; it only matches itself
+\end{code}
+
 
-  | WildCard   -- This type variable matches anything,
-               -- and does not affect the substitution
+%************************************************************************
+%*                                                                     *
+               Unification monad
+%*                                                                     *
+%************************************************************************
 
+\begin{code}
 newtype UM a = UM { unUM :: (TyVar -> BindFlag)
                         -> MaybeErr Message a }