On Dec 15, 9:05 am, [EMAIL PROTECTED] wrote: > On Dec 15, 8:33 am, Carl Banks <[EMAIL PROTECTED]> wrote: > > > > > On Dec 14, 4:15 pm, Neil Cerutti <[EMAIL PROTECTED]> wrote: > > > > When implementing the rich comparison operators for some sort of > > > container, it's tempting to save code by doing something like: > > > > class LarchTree: > > > ... > > > def __gt__(self, other): > > > # A lot of code to traverse the tree > > > def __le__(self): > > > return not self > other > > > > However, if I'm thinking correctly, this is a bad idea. The > > > reasoning being that > and <= are not required to be each others > > > opposite for arbitrary value types, and may not even both be > > > supplied by the contained objects. > > > And yet, by the same reasoning, using > and <= for list and tuple is > > also a "bad idea". > > My reasoning is (I hope) that the container ought to support every > comparison operation supported by the contained objects. This can be > ensured by being careful in the implementation.
I see what you're asking now. Yep, probably a bad idea to use that shortcut. Carl Banks -- http://mail.python.org/mailman/listinfo/python-list
