[Python-3000] Fixing super anyone?

[Calvin Spealman]

I must have miscopied then because it worked perfectly here. Yes, I
meant to have the _superdesc defined inside the metaclass __init__,
but thought I could pull it out to make it cleaner. I forgot it
actually had to be there! Here is the metaclass that works.

class autosuper(type):
	def __init__(cls, name, bases, clsdict):
		class _superdesc(object):
			def __get__(self, obj, objcls):
				return super(cls, obj)
		cls.__super__ = _superdesc()

On 4/24/07, Steven Bethard <steven.bethard at gmail.com> wrote:
> On 4/23/07, Calvin Spealman <ironfroggy at gmail.com> wrote:
> > I will +1 on the self.__super__ suggestion. Hey, its very doable and I
> > even whipped it up with a simple metaclass, so it would be a tiny
> > change to 'type' in order to actually implement it as a standard
> > feature. The demonstration is as follows:
> >
> > class _superdesc(object):
> >     def __get__(self, obj, objcls):
> >         return super(cls, obj)
> >
> > class autosuper(type):
> >     def __init__(cls, name, bases, clsdict):
> >         cls.__super__ = _superdesc()
> >
> > class A(object):
> >     __metaclass__ = autosuper
> >     x = 1
> >
> > class B(A):
> >     x = 2
> >
> > assert B().__super__.x == 1
>
> Does that really work?  There's a typo in _superdesc (I don't know
> where 'cls' comes from) but if you meant 'objcls', here's what I get::
>
>     >>> class _superdesc(object):
>     ...     def __get__(self, obj, cls):
>     ...         return super(cls, obj)
>     ...
>     >>> class autosuper(type):
>     ...     def __init__(cls, name, bases, clsdict):
>     ...         cls.__super__ = _superdesc()
>     ...
>     >>> class A:
>     ...     __metaclass__ = autosuper
>     ...     def f(self):
>     ...         print 'A'
>     ...
>     >>> class B(A):
>     ...     def f(self):
>     ...         print 'B'
>     ...         self.__super__.f()
>     ...
>     >>> class C(A):
>     ...     def f(self):
>     ...         print 'C'
>     ...         self.__super__.f()
>     ...
>     >>> class D(B, C):
>     ...     def f(self):
>     ...         print 'D'
>     ...         self.__super__.f()
>     ...
>     >>> D().f()
>     D
>     B
>     B
>     B
>     ...
>     Traceback (most recent call last):
>       File "<interactive input>", line 1, in <module>
>     ...
>     RuntimeError: maximum recursion depth exceeded
>
> STeVe
> --
> I'm not *in*-sane. Indeed, I am so far *out* of sane that you appear a
> tiny blip on the distant coast of sanity.
>         --- Bucky Katt, Get Fuzzy
>


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