mkTcAppCo :: TcCoercion -> TcCoercion -> TcCoercion
-- No need to deal with TyConApp on the left; see Note [TcCoercions]
-- Second coercion *must* be nominal
mkTcAppCo (TcRefl r ty1) (TcRefl _ ty2) = TcRefl r (mkAppTy ty1 ty2)
mkTcAppCo :: TcCoercion -> TcCoercion -> TcCoercion
mkTcAppCo (TcRefl r ty1) (TcRefl _ ty2) = TcRefl r (mkAppTy ty1 ty2)
mkTcAppCo (TcRefl r ty1) (TcRefl _ ty2) = TcRefl r (mkAppTy ty1 ty2)