[Python-ideas] Add OrderedSet now that OrderedDict is in collections
Mart Sõmermaa
mrts.pydev at gmail.com
Fri May 8 09:58:10 CEST 2009
On Sun, Apr 12, 2009 at 1:22 AM, Mart Sõmermaa <mrts.pydev at gmail.com> wrote:
> There was a somewhat ancient discussion on OrderedDict and OrderedSet
> before: http://mail.python.org/pipermail/python-dev/2005-March/051915.html
>
> The resolution seemed to be that neither of them should be in stdlib. Now
> that OrderedDict is in and Raymond Hettinger has created a solid OrderedSet
> implementation: http://code.activestate.com/recipes/576694/ , could the
> latter also be included in collections?
So, let's review what we have in terms of data structures:
Structure Stable Unique Python type
-------------------------------------------
Multiset no no -
Set no yes set
Map no yes dict
List yes no list, tuple
Ordered set yes yes -
Ordered map yes yes collections.OrderedDict
where "stable" means that input order is retained.
As Multiset is arguably quite useless, only Ordered set is missing
from "total" coverage of data structures. And it is practical as well.
Am I really the only one who would like to see this in stdlib?
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