FYI - xor is an "exclusive or". It has the following rules: 
(1 xor 1) == 0
(1 xor 0) == 1
(0 xor 1) == 1
(0 xor 0) == 0
(0 xor 1 xor 1) == 0
(0 xor 1 xor 0) == 1
etc etc

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Meaning that it will return true if and only if exactly 1 of the xor'd variables returns true.

In reply to xor = by hubb0r
in thread adding/subtracting calender dates by Fuism

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