> There is no way to have a value that isn't a value, in Python. The > concept doesn't make sense and would break all kinds of things. > (That's why, when a special function like __getitem__ has to be able > to return literally anything, it signals "nothing to return" by > raising an exception.)
I accept that it might be difficult to implement. I see that it would break things at cpython. Will definitely break some of the stdlib. E.g. inspect stuff. It wouldn’t break any of the existing python code. So yes, might not be a minor change. Could it be done nicely and easily by someone with relevant experience? I don’t know. But I fail to see why it doesn’t make sense - that’s a strong statement. It would be a value, just a value that is treated with exception in this particular case. There is definitely code at that level - resolving args, kwargs, dealing with “/" and “*” in relation to arguments provided, etc. It would take effect only on keyword arguments with defaults, if so then fairly contained matter. It could be a default of a keyword argument itself, would have a type and everything as any other object. _______________________________________________ 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/YN3QPKPCN2HSTARQNXXHXZWJTH3AA5RI/ Code of Conduct: http://python.org/psf/codeofconduct/
