[Python-Dev] defaultdict proposal round three

["Martin v. Löwis"]

Raymond Hettinger wrote:
>>Yes, I now agree. This means that I'm withdrawing proposal A (new
>>method) and championing only B (a subclass that implements
>>__getitem__() calling on_missing() and on_missing() defined in that
>>subclass as before, calling default_factory unless it's None). I don't
>>think this crisis is big enough to need *two* solutions, and this
>>example shows B's superiority over A.
> 
> 
> FWIW, I'm happy with the proposal and think it is a nice addition to Py2.5.

I agree. I would have preferred if dict itself was modified, but after
ruling out changes to dict.__getitem__, d[k]+=1 is too important to
not support it.

Regards,
Martin