# File lib/mcollective/ddl/agentddl.rb, line 85
      def display(pref)
        # defaults to old behavior, complain if its supplied and invalid
        unless [:ok, :failed, :flatten, :always].include?(pref)
          raise "Display preference #{pref} is not valid, should be :ok, :failed, :flatten or :always"
        end

        action = @current_entity
        @entities[action][:display] = pref
      end