Re: Python 3: dict & dict.keys()

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Date	Wed, 24 Jul 2013 08:57:11 -0700
From	Ethan Furman <ethan@stoneleaf.us>
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Subject	Re: Python 3: dict & dict.keys()
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On 07/24/2013 05:51 AM, Oscar Benjamin wrote:
>
> On Jul 24, 2013 7:25 AM, "Peter Otten" <__peter__@web.de <mailto:peter__@web.de>> wrote:
>>
>> Ethan Furman wrote:
>>
>> > So, my question boils down to:  in Python 3 how is dict.keys() different
>> > from dict?  What are the use cases?
>>
>> I just grepped through /usr/lib/python3, and could not identify a single
>> line where some_object.keys() wasn't either wrapped in a list (or set,
>> sorted, max) call, or iterated over.
>>
>> To me it looks like views are a solution waiting for a problem.
>
> What do you mean? Why would you want to create a temporary list just to iterate over it explicitly or implicitly (set,
> sorted, max,...)?

You wouldn't.  But you don't need .keys() for that either as you can just use the dict itself.

My point is that in 2.x .keys() did something different from the dict, while in 3.x it appears to me that they are the same.

Peter's point is that in the stdlib the new functionality of .keys() is never used, not even once.

--
~Ethan~

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Thread

Re: Python 3: dict & dict.keys() Ethan Furman <ethan@stoneleaf.us> - 2013-07-24 08:57 -0700
  Re: Python 3: dict & dict.keys() Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-07-25 05:48 +0000
    Re: Python 3: dict & dict.keys() Chris Angelico <rosuav@gmail.com> - 2013-07-25 16:02 +1000
      Re: Python 3: dict & dict.keys() Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-07-25 07:27 +0000
        Re: Python 3: dict & dict.keys() Chris Angelico <rosuav@gmail.com> - 2013-07-25 18:15 +1000
          Re: Python 3: dict & dict.keys() Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-07-25 09:44 +0000
            Re: Python 3: dict & dict.keys() Chris Angelico <rosuav@gmail.com> - 2013-07-25 20:34 +1000
              Re: Python 3: dict & dict.keys() Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-07-25 14:57 +0000
                Re: Python 3: dict & dict.keys() Chris Angelico <rosuav@gmail.com> - 2013-07-26 01:07 +1000
    Re: Python 3: dict & dict.keys() Johannes Bauer <dfnsonfsduifb@gmx.de> - 2013-07-25 15:22 +0200
    Re: Python 3: dict & dict.keys() Ethan Furman <ethan@stoneleaf.us> - 2013-07-25 06:57 -0700

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