'is' versus '=='

[Michael Hudson]

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.

-- 
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