Jordan Rastrick wrote: > I don't want to order the objects. I just want to be able to say if one > is equal to the other. > > Here's the justification given: > > The == and != operators are not assumed to be each other's > complement (e.g. IEEE 754 floating point numbers do not satisfy > this). It is up to the type to implement this if desired. > Similar for < and >=, or > and <=; there are lots of examples > where these assumptions aren't true (e.g. tabnanny). > > Well, never, ever use equality or inequality operations with floating > point numbers anyway, in any language, as they are notoriously > unreliable due to the inherent inaccuracy of floating point. Thats > another pitfall, I'll grant, but its a pretty well known one to anyone > with programming experience. So I don't think thats a major use case. >
I think this is referring to IEEE 754's NaN equality test, which basically states that x==x is false if-and-only-if x.isNaN() is true. -- http://mail.python.org/mailman/listinfo/python-list
