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