[Python-Dev] PEP 318 - posting draft

[Guido van Rossum]

>     >> 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/)