On 10/19/2019 07:56 PM, Steve Jorgensen wrote:
When using a custom classdict to implement a DSL or use in the body of a class definition, from what I can tell by experiment, the classdict takes priority, and the surrounding context is only referenced if trying to get an item from the classdict raises `KeyError`.
Thank you for the examples. As you have discovered, the issue is that when Python is processing a class and gets a name (whether a def, a property, a variable, etc., is irrelevant) it tries to look that name up in the class_dict that was returned by __prepare__, and that class_dict has one shot at it -- either return an object for the name, or raise KeyError -- in which case Python will keep looking up the scope in an attempt to find a match. Having said all that, I'm now wondering if wrapping a super() call in a try/except inside class_dict.__get_item__ might solve the problem -- although, even if that worked, you would have the reverse problem of wanting a name to be new in your class, but already existing outside. The solution I use in aenum.Enum is an extra variable, _ignore_, that lists all names that shouldn't be shadowed in the new dict; it starts as being set to property, classmethod, and staticmethod, and the user can replace that list with whatever they like. -- ~Ethan~ _______________________________________________ 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/LEKGEOCUNHPGA2BTXZJEMBVIHIEAHZLC/ Code of Conduct: http://python.org/psf/codeofconduct/
