I think if you settle for the args being combined into a tuple you could essentially create a tagged union and the type checker should be able to refine off the

I think if you settle for the args being combined into a tuple you could essentially create a tagged union and the type checker should be able to refine off the comparison. Type would be something like: Union[Tuple[Literal[“thing1”], TypeX], Tuple[Literal[“thing2”], TypeY]]