[Python-Dev] Proposal: defaultdict

[Guido van Rossum]

On 2/17/06, "Martin v. Löwis" <martin at v.loewis.de> wrote:
> That's why I think has_key and in should return True for any key.
> This leaves keys(), items(), and values(). From a pure point of
> view, they should return infinite sets. Practicality beats purity,
> so yes, d[k] could be considered a modifying operation.

I think practicality beats purity even for has_key/in; IMO these
operations are more useful when they match keys() instead of always
returning True. But someone should start writing some code to play
with this.

I have a working patch (including a hack for PyDict_GetItem()):
python.org/sf/1433928

So there's no excuse to be practical now.

--
--Guido van Rossum (home page: http://www.python.org/~guido/)