Re: Pragmatics of the standard is() function

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Date	Sat, 26 Nov 2011 23:38:26 +0100
From	Alexander Kapps <alex.kapps@web.de>
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On 26.11.2011 22:20, candide wrote:

You already got answers for the "is" vs. "==" difference. I'd like 
to add the following.

> In which cases should we use the is() function ?

"is" is not a function, It's an operator, just like == or +.

> is() function makes comparaison of (abstract representation of)
> adresses of objects in memory.

That's an implementation detail. CPython (and maybe others) 
implement "is" in terms of memory addresses. Other implementations 
might use an object ID number or whatever else.

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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