boolean xor

[Rainer Deyke]

"Andrew Dalke" <dalke at acm.org> wrote in message
news:93i9ff$q4l$1 at slb0.atl.mindspring.net...
> The expression "not ( (a and b) or (not (a or b)) )"
> checks the truth value of a and b, which means it calls
> __nonzero__ or __len__ as unary methods of the object.
> The == is a binary operator which may call the __coerce,
> __cmp__ or __rcmp__ methods, so your version does something
> different than the original code.

You could, however, remove a redundant 'not' from the original:

def xor(a, b): return (a or b) and not (a and b)


--
Rainer Deyke (root at rainerdeyke.com)
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