Steven D'Aprano <ste...@remove.this.cybersource.com.au> wrote: > I've already mentioned NaNs. Sentinel values also sometimes need to > compare not equal with themselves. Forcing them to compare equal will > cause breakage.
There's a conflict between such domain-specific considerations (NaNs, strange sentinels, SAGE's equations), and relatively natural assumptions about an == operator, such as it being an equivalence relation. I don't know how to resolve this conflict without introducing a new function which is (or at least strongly encourages developers to arrange for it to be) an equivalence relation. -- [mdw] -- http://mail.python.org/mailman/listinfo/python-list
