On Sat, 2009-03-07 at 03:07 -0500, Albert Hopkins wrote: > On Fri, 2009-03-06 at 23:57 -0800, Paul Rubin wrote: > > alex23 <wuwe...@gmail.com> writes: > > > But _you_ only _just_ stated "It does have some (generally small) > > > performance ramifications as > > > well" and provided timing examples to show it. Without qualification. > > > > The performance difference can be large if the objects are (for > > example) long lists. > > I would think (not having looked) that the implementation of == would > first check for identity (for performance reasons)... but then that lead > me to ask: can an object be identical but not equal to itself?
... answered my own question class Foo: def __eq__(self, b): return False >>> x == Foo() >>> x is x --> True >>> x == x --> False -- http://mail.python.org/mailman/listinfo/python-list