GBBopen 1.5 Reference -- xor

xor

xor &rest args => boolean [Function]

Purpose
Return the exclusive or (XOR) of zero or more arguments.

Package :gbbopen-tools

Module :gbbopen-tools

Arguments and values

arg		A generalized boolean (an object)
boolean		A generalized boolean

Returns
True if there are an even odd number of true arguments; nil otherwise.

Examples

  > (xor)
  nil
  > (xor nil nil)
  nil
  > (xor 't 't)
  nil
  > (xor nil 't)
  t
  > (xor 't nil)
  t
  > (xor nil 't nil 't 't nil)
  t
  >

xor