On Tue, May 30, 2017 at 7:06 AM, Matt Gilson <matt@getpattern.com> wrote:
On Mon, May 29, 2017 at 11:59 AM, Neil Girdhar <mistersheik@gmail.com> wrote:
A long time ago, I proposed that the dict variants (sorteddict, defaultdict, weakkeydict, etc.) be made more discoverable by having them specified as keyword arguments and I got the same feedback that the poster here is getting. Now, instead of moving these classes into dict, why not have a factory like
dict.factory(values=None, *, ordered=True, sorted=False, has_default=False, weak_keys=False, weak_values=False, …)
Hmm ... I don't think that I like this. For one, it greatly increases the amount of surface area that needs to be maintained in the standard library. As far as I know, we don't currently have a OrderedWeakKeyDictionary with defaultdict behavior.
"defaultdict behavior" can be tacked onto anything:
class OrderedDefaultDict(collections.OrderedDict): ... def __missing__(self, key): ... self[key] = [] ... return self[key]
The core functionality of defaultdict is part of dict (the fact that __missing__ gets called). The core functionality of weak references could easily be added to dict too, if something like this were wanted. So a lot of these would indeed be orthogonal. That said, though, I don't know of many situations in which you would need an OrderedWeakKeyDictionary, so if you have to write some custom code to make that happen, so be it. ChrisA