Result of ``a is b''
afriere at yahoo.co.uk
Wed Mar 17 04:53:29 CET 2004
Skip Montanaro <skip at pobox.com> wrote in message news:<mailman.52.1079472192.742.python-list at python.org>...
> No, its behavior is quite well-specified. It does a pointer comparison.
> Here is my "is" rule:
> Use "is" to compare two objects only if one is explicitly known to be a
> singleton defined by the language (None, Ellipsis, True, False).
> and its corrolary:
> Never use "is" to compare two programmer-defined variables.
What about when it is an object explicitly known to be singleton
defined by the programmer. ;)
Another possible use, would be to type test, eg. 'foo.__class__ is
Foo', bearing in mind that one should avoid type testing in favour of
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