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Aug. 29, 2019
10:32 p.m.
On Fri, Aug 30, 2019 at 8:28 AM Guido van Rossum <guido@python.org> wrote:
Open question: at runtime, what should `int | str` return? I don't want this to have to import the typing module. Maybe we could make a very simple `Union` builtin. This can then also be used by `~int` (which is equivalent to `int | None`).
Would it be okay to have a very simple Union builtin now, and it just always returns exactly that, and then in the future it might potentially actually return Union[int, str] ? I'm not pushing for it *now*, but it would be extremely handy in the future to be able to say isinstance(3, int|str) and have it be meaningful. ChrisA