Rails: nil error class not found -

my code cannot find module , returns nil error.

undefined method `next' nil:nilclass 

here code

module test   class mytestclass      before_save :cid      def cid       mytestclass.maximum(:id).next #error here, can't find mytestclass      end end 

i tried variants test::mytestclass none worked.

in context, can safely use maximum(:id).next