[Python-Dev] More compact dictionaries with faster iteration

Armin Rigo arigo at tunes.org
Mon Dec 10 10:40:30 CET 2012

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. :-/

A bientôt,


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