Steven D'Aprano <[EMAIL PROTECTED]> writes:
> On Sun, 24 Aug 2008 11:09:46 +0200, Hrvoje Niksic wrote:
>
>> Use [classmethod] when your method needs to know what class it is
>> called from.
>
> Ordinary methods know what class they are called from
I guess I should have added "and no more". :-)
> Why is this useful? Consider the dict method "fromkeys". You can
> call it from any dictionary, but it doesn't care which dict you call
> it from, only that it is being called from a dict:
That's also a good example of the difference between classmethod and
staticmethod, since fromkeys is smart enough to use the type
information.
>>> class X(dict):
... pass
...
>>> x = X.fromkeys({1: 2})
>>> type(x)
<class '__main__.X'> # not <type 'dict'>
If 'fromkeys' were a staticmethod, it would have to be hardcoded to
always create dicts.
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