On Sat, Jul 27, 2019 at 5:16 AM Erik Aronesty <e...@q32.com> wrote: > > I just spend a while tracking down and killing all "if Enum" and "if not > Enum" bugs in my code. I was frankly shocked that this didn't raise a > ValueError to begin with. > > Apparently all enums are true/false depending on whether the underlying > value is truthy or falsy. > > Which breaks the abstraction Enum's are trying to achieve because now the > user of an Enum has to know "stuff" about the underlying value and how it > behaves.
If you want to abstract away the underlying value, just don't have one? >>> from enum import Enum, auto >>> class Color(Enum): ... red = auto() ... green = auto() ... blue = auto() ... >>> bool(Color.red) True >>> bool(Color.green) True >>> bool(Color.blue) True They happen to have the values 1, 2, and 3, but that doesn't matter. When an enum has to correspond to a real underlying value, it behaves as similarly to that value as possible: >>> http.HTTPStatus.METHOD_NOT_ALLOWED == 405 True Thus it should also inherit its truthiness from that value. ChrisA -- https://mail.python.org/mailman/listinfo/python-list
