On 07/08/2014 07:53 AM, Anders J. Munch wrote:
So I make this claim: float.__eq__ implementing IEEE-754 NaN comparison rules creates real problems for developers. And it has never, ever, helped anyone do anything. "Never" is a strong claim, and easily disproven if false: Simply provide a counterexample. So that is my challenge: If you have a program (a pre-existing and useful one, not something artificial created for this challenge) that benefits from NaN!=NaN and that would fail if x==x for all float objects x, then please come forward and show it, and I'll buy you a beer the next time I'm at PyCon.
I would suggest you ask for this on the numerical mailing lists instead of here -- and you may not want to offer a beer to everyone that has an anecdote for NaN behavior being useful.
-- ~Ethan~ -- https://mail.python.org/mailman/listinfo/python-list
