[Python-Dev] Deprecated __cmp__ and total ordering

[Michael Foord]

Raymond Hettinger wrote:
>
> [Mart Sõmermaa]
>> To provide total ordering without __cmp__ one has to implement all of
>>  __lt__, __gt__, __le__, __ge__, __eq__ and __ne__. However, in all
>> but a few cases it suffices only to provide a "real" implementation for
>> e.g. __lt__ and define all the other methods in terms of it as follows:
>
> FWIW, I'm working on a solution for the problem using class decorators.
> The idea is that it would scan a class and fill-in missing methods based
> on the ones already there.  That way, any one of the four ordering
> relations can be provided as a starting point and we won't have to
> annoint one like __lt__ as the one true underlying method.
>
> When it's ready, I'll bring it to python-dev for discussion.

Is there something you don't like about this one: 
http://code.activestate.com/recipes/576529/


Michael

>
>
> Raymond
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