default behavior

[Christian Heimes]

> I just went and read the entry that had the bogus claim -- personally, I 
> didn't see any confusion.  I would like to point out the __missing__ is 
> *not* part of dicts (tested on 2.5 and 2.6 -- don't have 2.7 installed yet).

I beg your pardon but you are wrong. __missing__ is available for all
*subclasses* of dict since Python 2.5. See
http://svn.python.org/view/python/branches/release25-maint/Objects/dictobject.c?revision=81031&view=markup

>>> class mydict(dict):
...     def __missing__(self, key):
...         print "__missing__", key
...         raise KeyError(key)
...
>>> m = mydict()
>>> m[1]
__missing__ 1
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "<stdin>", line 4, in __missing__
KeyError: 1

Christian