class<<self

问：
Hi
   I have code like

   class A
     class <<self
        def first
         -------
        end
        def second
          ------
         end
      end
    end

    What I understood is now the def first and second becomes class methods of class A..Am I right? Is that its only use?

Thanks in advance
Sijo

答：
Yes you understood it well, and it's its only use. You could also type:

class A
def self.first
end
end

or

class << A
def first
end
end