Christopher King wrote:
I would go with __cmp__ which covers them all. 1 for greater, 0 for equal,
-1 for less than.
So-called "rich comparisons" using __lt__, __gt__, etc. have been
preferred since Python 2.1. The major advantage of them is that they can
be used for more complicated data types, e.g. with sets where > means
superset and < means subset:
>>> a = set([1, 2, 3, 4])
>>> b = set([2, 3, 4, 5])
>>>
>>> a < b # a is not a subset of b
False
>>> a > b # neither is it a superset
False
>>> a == b # and they're not equal either
False
>>> a & b # but they do overlap:
set([2, 3, 4])
In Python 2.x, __cmp__ is only used as a fall-back if the rich
comparisons aren't defined. In Python 3.x, __cmp__ is gone: even if you
define it, it won't be used.
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