Michael Hudson mwh at python.net
Mon May 7 13:24:03 EDT 2001

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Aaron Ginn <aaron.ginn at motorola.com> writes:

> Maybe I have an incorrect understanding of the 'is' operator, but I
> was under the impression that 'is' and '==' operated the same way.

Nope.

>From http://www.python.org/doc/current/ref/comparisons.html:

  The operators is and is not test for object identity: x is y is true
  if and only if x and y are the same object. x is not y yields the
  inverse truth value.

The moral?  Don't use "is" on strings.  The results are predictable,
but unlikely to be what you want.

Cheers,
M.

-- 
  You can lead an idiot to knowledge but you cannot make him 
  think.  You can, however, rectally insert the information, 
  printed on stone tablets, using a sharpened poker.        -- Nicolai
               -- http://home.xnet.com/~raven/Sysadmin/ASR.Quotes.html

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