dict: keys() and values() order guaranteed to be same?

Chris Angelico rosuav at gmail.com
Mon Jul 23 18:18:54 CEST 2012


On Tue, Jul 24, 2012 at 1:20 AM, Steven D'Aprano
<steve+comp.lang.python at 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



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