[Python-Dev] More compact dictionaries with faster iteration

[Antoine Pitrou]

Le Mon, 10 Dec 2012 10:40:30 +0100,
Armin Rigo <arigo at tunes.org> a écrit :
> Hi Raymond,
> 
> On Mon, Dec 10, 2012 at 2:44 AM, Raymond Hettinger
> <raymond.hettinger at gmail.com> wrote:
> > Instead, the data should be organized as follows:
> >
> >     indices =  [None, 1, None, None, None, 0, None, 2]
> >     entries =  [[-9092791511155847987, 'timmy', 'red'],
> >                 [-8522787127447073495, 'barry', 'green'],
> >                 [-6480567542315338377, 'guido', 'blue']]
> 
> As a side note, your suggestion also enables order-preserving
> dictionaries: iter() would automatically yield items in the order they
> were inserted, as long as there was no deletion.  People will
> immediately start relying on this "feature"...  and be confused by the
> behavior of deletion. :-/

If that's really an issue, we can deliberately scramble the iteration
order a bit :-) (of course it might negatively impact HW prefetching)

Regards

Antoine.