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

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Date	Thu, 26 Jul 2012 14:06:03 -0700
From	Ethan Furman <ethan@stoneleaf.us>
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Chris Angelico wrote:
> 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.

Yes, it would.  The docs say that .keys(), .values(), etc., will 
maintain order unless the dict is modified in between calls.

~Ethan~

Thread

dict: keys() and values() order guaranteed to be same? Henrik Faber <hfaber@invalid.net> - 2012-07-23 13:23 +0200
  Re: dict: keys() and values() order guaranteed to be same? Philipp Hagemeister <phihag@phihag.de> - 2012-07-23 13:40 +0200
    Re: dict: keys() and values() order guaranteed to be same? Henrik Faber <hfaber@invalid.net> - 2012-07-23 14:19 +0200
  Re: dict: keys() and values() order guaranteed to be same? Stefan Behnel <stefan_ml@behnel.de> - 2012-07-23 13:43 +0200
  Re: dict: keys() and values() order guaranteed to be same? Stefan Behnel <stefan_ml@behnel.de> - 2012-07-23 13:58 +0200
    Re: dict: keys() and values() order guaranteed to be same? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-07-23 15:20 +0000
      Re: dict: keys() and values() order guaranteed to be same? Chris Angelico <rosuav@gmail.com> - 2012-07-24 02:18 +1000
      Re: dict: keys() and values() order guaranteed to be same? Ethan Furman <ethan@stoneleaf.us> - 2012-07-26 14:06 -0700
      Re: dict: keys() and values() order guaranteed to be same? Ethan Furman <ethan@stoneleaf.us> - 2012-07-26 14:03 -0700

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