Guido van Rossum wrote:
your original remark claimed something wasn't syntactic sugar because of the difference between the box and its contents, and that's what I disagree with.
Maybe I misunderstood -- you seemed to be saying that algebraic types were just syntactic sugar for something. Perhaps I should have asked what you thought they were syntactic sugar *for*?
I was also responding to a comment that values in Python are already tagged with their type, so tagged unions are unnecessary. But the type tag of a Python object is not equivalent to the tag of an algebraic type, because the latter conveys information over and above the type of its payload.