C++ Standard Evolution Active Issues List, #37. Logical xor operatorより一部引用。
(snip) This has traditionally been dismissed as un-necessary, as it is equivalent to boolean operator!=, and there is no short-circuiting benefit to justify adding it. However, contextual conversions to 'bool' are handled specially for logical operators, and in that context it would be completing a hole in the language. (snip)function<void()> a; function<void()> b; assert(a != b); // does not compile assert(a ^^ b); // would compile, and assert!
(a ^^ b);」が煽り系顔文字に見えて仕方ない。