John Salerno wrote: > Diez B. Roggisch wrote: > >> I can't imagine what you're actually after here, but assuming that you >> really need this > > Hard to explain because I'm still trying to figure out how to do it > myself. I'm trying to solve a little puzzle using Python, even though > I'm sure it's not necessary. Basically W, X, Y and Z are propositions > that are either true or false, and the puzzle lists a few statements > such as "Exactly one of X, Y and Z is true", and I'm trying to work out > a little algorithm that might test for this kind of stuff.
Then use a Proposition-class that holds the actual value. > Another thing I'm trying to do is write a function that tests to see if > a list contains exactly one true item, and the rest are false (obviously > this would have to be a list of boolean values, I guess). No - you can for example override the comparison-semantics on the Proposition-class to be comparable with True/False with the proper semantics: class Proposition(object): def __init__(self, v): self._v = v def __eq__(self, o): return self._v == o TrueProposition = Proposition(True) FalseProposition = Proposition(False) print True == TrueProposition print False == TrueProposition print False == FalseProposition Diez -- http://mail.python.org/mailman/listinfo/python-list