[Python-3000] Fixing super anyone? (original) (raw)

Steven Bethard steven.bethard at gmail.com
Tue Apr 24 06:22:44 CEST 2007

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

More information about the Python-3000 mailing list