> Per the AutoName example at > https://docs.python.org/3/library/enum.html#using-automatic-values, > one can easily use _generate_next_value_ to derive a member's value from its > name, but that is only invoked when the object's value is an instance of > auto(), so if you want to give an enum member an explicit value _and_ have an > attribute such as label derived from its name, that's a hard nut to > crack. > An example usage of what I'm suggesting would be something like… > class ChoiceEnum(Enum): > _use_context_ = True > > def __new__(cls, value, context): > obj = object.__new__(cls) > obj._value_ = value > obj.label = context.name.capitalize() > > class Color(ChoiceEnum): > SMALL = 'S' > MEDIUM = 'M' > LARGE = 'L' > > print(Color.SMALL.label) # Prints 'Small'
My though about `_use_context_ = True` is not _only_ about backward compatibility. It is also about not making simpler cases deal with the fact that the `context` argument will be passed to `__new__` though I guess one could argue that cases where `__new__` is used are already not simple. _______________________________________________ Python-ideas mailing list -- python-ideas@python.org To unsubscribe send an email to python-ideas-le...@python.org https://mail.python.org/mailman3/lists/python-ideas.python.org/ Message archived at https://mail.python.org/archives/list/python-ideas@python.org/message/Z56NRWE2R4NBUGGXJZTMZ5W5TGCDFPT6/ Code of Conduct: http://python.org/psf/codeofconduct/
