[Python-Dev] PEP 318 - posting draft
Guido van Rossum
guido at python.org
Wed Mar 24 13:32:04 EST 2004
> >> I think this use case is rather elegant:
> >>
> >> def singleton(cls):
> >> return cls()
> >>
> >> class Foo [singleton]:
> >> ...
>
> Guido> And how would this be better than
>
> Guido> class Foo(singleton):
> Guido> ...
>
> Guido> (with a suitable definition of singleton, which could just be
> Guido> 'object' AFAICT from your example)?
>
> "Better"? I don't know. Certainly different. In the former, Foo gets
> bound to a class instance. In the latter, it would be a separate step which
> you omitted:
>
> class Foo(singleton):
> ...
> Foo = Foo()
Ok, so the metaclass would have to be a little different, but this can
be done with metaclasses. (But I think that this in particular
example, declaring the instance through the class is merely
confusing. :-)
--Guido van Rossum (home page: http://www.python.org/~guido/)
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