Keyword for exclusive or in ruby?

Question

Does Ruby have a plain-English keyword for exclusive or, like they have \"and\" and \"or\"? If not, is this because exclusive or doesn\'t allow evaluation short-cutting?

Answer 1

John's answer appears incorrect. In irb with 1.9.3, xor("cupcake", false) returns true, as you'd expect.

1.9.3-p429 :104 > def xor(a,b)
1.9.3-p429 :105?>     (a and (not b)) or ((not a) and b)
1.9.3-p429 :106?>   end
 => nil 
1.9.3-p429 :107 > xor(false, true)
 => true 
1.9.3-p429 :108 > xor("cupcake", false)
 => true