ram.rachum at gmail.com
Tue Sep 24 14:27:08 CEST 2013
I think that your mistake is defining OrderedDict as a dict sorting by
insertion order. I see no reason to define it that way, and the fact that
insertion order is the default is not a reason in my opinion. It's just a
dict with an order, and I see no reason to not let users move elements
about as they wish. Yes, I'm aware that the documentation defined
OrderedDict your way too; I still think it's a pointless restriction.
I've used my `OrderedDict.sort` at least 10 times. Just today I've used it
again. I was putting three items in an ordrered dict, with keys 'low',
'medium' and 'high'. I wanted to have them sorted as 'low', 'medium' and
'high' but the insertion order was different because of the algorithm that
calculated them. (Also not all 3 items were guaranteed to exist, I wanted
to sort those that existed.)
So I created an OrderedDict of my subclass and called `.sort`.
I'm sure you can think of a bunch more examples, if not I can give them to
On Tuesday, September 24, 2013 3:13:15 PM UTC+3, Steven D'Aprano wrote:
> On Tue, Sep 24, 2013 at 04:49:20AM -0700, Ram Rachum wrote:
> > What do you think about providing an `OrderedDict.sort` method? I've
> > using my own `OrderedDict` subclass that defines `sort` for years, and I
> > always wondered why the stdlib one doesn't provide `sort`.
> > I can write the patch if needed.
> I'm not entirely sure why anyone would need an OrderedDict sort method.
> Ordered Dicts store keys by insertion order. Sorting the keys goes
> against the purpose of an OrderedDict.
> I can understand a request for a SortedDict, that keeps the keys in
> sorted order as they are deleted or inserted. I personally don't have
> any need for one, since when I need the keys in sorted order I just
> sort them on the fly:
> for key in sorted(dict):
> but in any case, that's a separate issue from sorting an OrderedDict.
> Can you explain the use-case for why somebody might want to throw away
> the insertion order and replace with sorted order?
> Python-ideas mailing list
-------------- next part --------------
An HTML attachment was scrubbed...
More information about the Python-ideas