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Re: intersection, union, difference, symmetric difference for dictionaries

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Date Tue, 25 Feb 2014 16:36:08 -0600
From Tim Chase <python.list@tim.thechases.com>
To python-list@python.org
Subject Re: intersection, union, difference, symmetric difference for dictionaries
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Show key headers only | View raw

On 2014-02-25 22:21, Duncan Booth wrote:
> > It would save some space if I didn't have to duplicate all the
> > keys into sets (on the order of 10-100k small strings), instead
> > being able to directly perform the set-ops on the dicts.  But
> > otherwise, it was pretty readable & straight-forward.
> >     
> It doesn't matter whether they were small strings or full-length
> novels, creating a set from a dict doesn't duplicate any strings.  

pre-my-new-learning-about .viewkeys() it sounds like set(my_dict)
would have the overhead of storing an additional reference to a
string per set-entry (rather than duplicating every string).
With .viewkeys()/.keys(), it sounds like that overhead would go away.

-tkc

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intersection, union, difference, symmetric difference for dictionaries mauro <mauro@gmail.com> - 2014-02-25 20:32 +0000
  Re: intersection, union, difference, symmetric difference for dictionaries Nick Timkovich <prometheus235@gmail.com> - 2014-02-25 14:37 -0600
  Re: intersection, union, difference, symmetric difference for dictionaries Skip Montanaro <skip@pobox.com> - 2014-02-25 14:40 -0600
  Re: intersection, union, difference, symmetric difference for dictionaries Peter Otten <__peter__@web.de> - 2014-02-25 21:53 +0100
  Re: intersection, union, difference, symmetric difference for dictionaries Peter Otten <__peter__@web.de> - 2014-02-25 21:58 +0100
  Re: intersection, union, difference, symmetric difference for dictionaries Tim Chase <python.list@tim.thechases.com> - 2014-02-25 15:03 -0600
    Re: intersection, union, difference, symmetric difference for dictionaries Duncan Booth <duncan.booth@invalid.invalid> - 2014-02-25 22:21 +0000
      Re: intersection, union, difference, symmetric difference for dictionaries Tim Chase <tim@thechases.com> - 2014-02-25 16:35 -0600
      Re: intersection, union, difference, symmetric difference for dictionaries Tim Chase <python.list@tim.thechases.com> - 2014-02-25 16:36 -0600
      Re: intersection, union, difference, symmetric difference for dictionaries Oscar Benjamin <oscar.j.benjamin@gmail.com> - 2014-02-25 22:58 +0000
    Re: intersection, union, difference, symmetric difference for dictionaries Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2014-02-25 23:10 +0000
      Re: intersection, union, difference, symmetric difference for dictionaries Tim Chase <python.list@tim.thechases.com> - 2014-02-25 20:21 -0600
  Re: intersection, union, difference, symmetric difference for dictionaries Ben Finney <ben+python@benfinney.id.au> - 2014-02-26 08:27 +1100
  Re:intersection, union, difference, symmetric difference for dictionaries Dave Angel <davea@davea.name> - 2014-02-25 16:35 -0500
  Re: intersection, union, difference, symmetric difference for dictionaries Peter Otten <__peter__@web.de> - 2014-02-25 22:54 +0100
  Re: intersection, union, difference, symmetric difference for dictionaries mauro <mauro@gmail.com> - 2014-02-25 22:02 +0000
  Re: intersection, union, difference, symmetric difference for dictionaries mauro <mauro@gmail.com> - 2014-02-25 22:03 +0000
  Re: intersection, union, difference, symmetric difference for dictionaries Tim Chase <python.list@tim.thechases.com> - 2014-02-25 16:10 -0600
  Re: intersection, union, difference, symmetric difference for dictionaries mauro <mauro@gmail.com> - 2014-02-25 22:11 +0000
    Re: intersection, union, difference, symmetric difference for dictionaries Mark Lawrence <breamoreboy@yahoo.co.uk> - 2014-02-25 22:35 +0000
  Re: intersection, union, difference, symmetric difference for dictionaries MRAB <python@mrabarnett.plus.com> - 2014-02-25 23:07 +0000
    Re: intersection, union, difference, symmetric difference for dictionaries Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2014-02-26 00:37 +0000
  Re: intersection, union, difference, symmetric difference for dictionaries Ben Finney <ben+python@benfinney.id.au> - 2014-02-26 10:14 +1100
  Re: intersection, union, difference, symmetric difference for dictionaries MRAB <python@mrabarnett.plus.com> - 2014-02-25 23:25 +0000
  Re: intersection, union, difference, symmetric difference for dictionaries Grant Edwards <invalid@invalid.invalid> - 2014-02-25 20:44 +0000
  Re: intersection, union, difference, symmetric difference for dictionaries John Gordon <gordon@panix.com> - 2014-02-25 20:44 +0000
    Re: intersection, union, difference, symmetric difference for dictionaries Chris Angelico <rosuav@gmail.com> - 2014-03-02 09:29 +1100

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