Re: Pragmatics of the standard is() function

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Date	Sun, 27 Nov 2011 09:22:40 +1100
Subject	Re: Pragmatics of the standard is() function
From	Chris Angelico <rosuav@gmail.com>
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On Sun, Nov 27, 2011 at 8:20 AM, candide <candide@free.invalid> wrote:
> is() function makes comparaison of (abstract representation of) adresses of
> objects in memory. Comparing addresses of objects is a low level feature
> performed by low level langages such as C but seldom needed in high level
> languages like Python, isn'it ?

You also want 'is' when you're testing for a singleton used as a default value:

DEFAULT = object()

def foo(arg1,arg2,arg3=DEFAULT):
    if arg3 is DEFAULT: print("You gave me two args")


ChrisA

Thread

Pragmatics of the standard is() function candide <candide@free.invalid> - 2011-11-26 22:20 +0100
  Re: Pragmatics of the standard is() function Roy Smith <roy@panix.com> - 2011-11-26 16:32 -0500
  Re: Pragmatics of the standard is() function Chris Angelico <rosuav@gmail.com> - 2011-11-27 09:22 +1100
  Re: Pragmatics of the standard is() function Alexander Kapps <alex.kapps@web.de> - 2011-11-26 23:38 +0100
  Re: Pragmatics of the standard is() function Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2011-11-26 23:01 +0000
    Re: Pragmatics of the is operator candide <candide@free.invalid> - 2011-11-27 02:42 +0100
      Re: Pragmatics of the is operator Chris Angelico <rosuav@gmail.com> - 2011-11-27 12:50 +1100
      Re: Pragmatics of the is operator Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2011-11-27 03:13 +0000
    Re: Pragmatics of the standard is() function Den <patentsvnc@gmail.com> - 2011-11-28 11:22 -0800
      Re: Pragmatics of the standard is() function Ethan Furman <ethan@stoneleaf.us> - 2011-11-28 12:05 -0800
      Re: Pragmatics of the standard is() function alex23 <wuwei23@gmail.com> - 2011-11-28 19:58 -0800
      Re: Pragmatics of the standard is() function Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2011-11-29 08:41 +0000
        Re: Pragmatics of the standard is() function Den <patentsvnc@gmail.com> - 2011-11-29 09:11 -0800
  Re: Pragmatics of the standard is() function Jean-Michel Pichavant <jeanmichel@sequans.com> - 2011-11-28 13:57 +0100

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