Chris Rebert wrote: > Using the xor bitwise operator is also an option: > bool(x) ^ bool(y)
I prefer something like: bool(a) + bool(b) == 1 It works even for multiple tests (super xor): if bool(a) + bool(b) + bool(c) + bool(d) != 1: raise ValueError("Exactly one of a, b, c and d must be true") Christian -- http://mail.python.org/mailman/listinfo/python-list