Correct substitution into theta types (after merge)

[ghc-hetmet.git] / compiler / typecheck / Inst.lhs

diff --git a/compiler/typecheck/Inst.lhs b/compiler/typecheck/Inst.lhs
index 63b5f26..cff48e3 100644 (file)
--- a/compiler/typecheck/Inst.lhs
+++ b/compiler/typecheck/Inst.lhs
@@ -261,7 +261,7 @@ instCallDicts loc [] = return ([], idCoercion)
 instCallDicts loc (EqPred ty1 ty2 : preds)
   = do  { unifyType ty1 ty2    -- For now, we insist that they unify right away 
                                -- Later on, when we do associated types, 
-                               -- unifyType might return a coercion
+                               -- unifyType :: Type -> Type -> TcM ([Inst], Coercion)
        ; (dicts, co_fn) <- instCallDicts loc preds
        ; return (dicts, co_fn <.> CoTyApp ty1) }
        -- We use type application to apply the function to the