Guido van Rossum <gu...@python.org> added the comment: > If you meant to say: why is typing.Union[] allowed, but not types.UnionType[]? That is intentional. types.UnionType is only meant for builtin types. Once you union with *any* type from typing, it will convert to a typing.Union.
But why? Just so types.UnionType (if it has a typevar) doesn’t have to support subscriptions? Even if this saves us now, I agree with OP that it ought to allow it, so we can deprecate typing.Union properly. And e.g. dict[str, T] works. -- --Guido (mobile) ---------- _______________________________________ Python tracker <rep...@bugs.python.org> <https://bugs.python.org/issue45418> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
