    # File lib/core/facets/string/xor.rb, line 11
      def ^(aString)
        a = self.unpack('C'*(self.length))
        b = aString.unpack('C'*(aString.length))
        if (b.length < a.length)
          (a.length - b.length).times { b << 0 }
        end
        xor = ""
        0.upto(a.length-1) { |pos|
          x = a[pos] ^ b[pos]
          xor << x.chr()
        }
        return(xor)
      end