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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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Xref: x330-a1.tempe.blueboxinc.net comp.lang.python:16265

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