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Date: Tue, 24 Jul 2012 02:18:54 +1000
Subject: Re: dict: keys() and values() order guaranteed to be same?
From: Chris Angelico <rosuav@gmail.com>
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On Tue, Jul 24, 2012 at 1:20 AM, Steven D'Aprano
<steve+comp.lang.python@pearwood.info> wrote:
> (Although if you think about the implementation of dicts as hash tables,
> it does seem likely that it is trivial to enforce this -- one would have
> to work *harder* to break that promise than to keep it.)

However, it would be quite reasonable to implement a dict as a splay
tree, and have values() return them nearest-first. This would mean
that just reading from the dictionary could change the order of
values(), yet it wouldn't make the implementation non-conformant.

Of course, if I want splay tree semantics, I'd rather explicitly ask
for that. But it'd be legal.

ChrisA