+
+
+ # Compare two Domain objects for sorting purposes. The comparison
+ # is based on their String representations.
+ #
+ # @param other [Domain] the Domain object to compare me to.
+ #
+ # @return [0,1,-1] a trinary indicator of how *self* relates to *other*,
+ # obtained by performing the same comparison on the String
+ # representations of *self* and *other*.
+ #
+ def <=>(other)
+ return self.to_s() <=> other.to_s()
+ end