On Thu, 2010-07-08 at 13:10 -0700, sturlamolden wrote: > What happens here? Does Python (2.6.5) have an "is not" operator? > > >>> a = 5 > >>> print (a is not False) > True > >>> print (a is (not False)) > False > >>> print (not (a is False)) > True > > It seems "y is not x" fits well with spoken English, but it is also a > bit surprising that "y is not x" does not mean "y is (not x)" but "not > (y is x)". Why does Python reorder is and not operators, and what are > the formal rules for this behavior?
Don't forget about the similar "not in", as in: >>> 'a' not in 'abc' False This is probably the section of documentation you want: http://docs.python.org/reference/expressions.html#notin -- John Krukoff <jkruk...@ltgc.com> Land Title Guarantee Company -- http://mail.python.org/mailman/listinfo/python-list
