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[Python-Dev] Python3 regret about deleting list.sort(cmp=...)

Reid Kleckner reid.kleckner at gmail.com
Sat Mar 12 23:09:29 CET 2011 
On Sat, Mar 12, 2011 at 4:58 PM, Nick Coghlan <ncoghlan at gmail.com> wrote:
> On Sat, Mar 12, 2011 at 4:50 PM, Reid Kleckner <reid.kleckner at gmail.com> wrote:
>> They should be able to use a slotted cmp_to_key style class:
>> http://docs.python.org/howto/sorting.html
>>
>> That will allocate 1 Python object with no dict per key, but that
>> might not be good enough.
>
> Tuples are already slotted, so that isn't likely to help in this case.

It's three allocations vs. one.  The first is tuple + str + int, while
the adapter is just one object.  I'm not sure how it eventually shakes
out, though.

That said, it's still worse than Python 2, which is zero allocations.  :)

Reid
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