Is it possible (and wise) to extend the None-type ?
Stef Mientki
stef.mientki at gmail.com
Wed Nov 26 16:26:58 EST 2008
<snip>
> Alternative (if you *really* want to save the explicit test) is to
> attach the behaviour modification to the *relevant* class:
>
> class NonEvent(Event):
> def do_nothing(self):
> pass
> skip = jump = hop = waltz = saunter = do_nothing
> def __len__(self):
> return 0
> NON_EVENT = NonEvent()
> del NonEvent
>
> # later:
>
> def amethod(self, event=NON_EVENT):
> if event: # still works thanks to __len__ above
> event.skip()
> # now can avoid test, if desired
> event.skip()
>
>
thanks guys, the Null, Dummy, Skipper, Nonevent class works great
> HTH ... BTW, ever heard of PEP 8?
>
I guess Python is missing some kind of CSS ;-)
cheers,
Stef
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