    # File lib/rbot/plugins.rb, line 481
        def add_botmodule(botmodule)
          raise TypeError, "Argument #{botmodule.inspect} is not of class BotModule" unless botmodule.kind_of?(BotModule)
          kl = botmodule.botmodule_class
          if @names_hash.has_key?(botmodule.to_sym)
            case self[botmodule].botmodule_class
            when kl
              raise "#{kl} #{botmodule} already registered!"
            else
              raise "#{self[botmodule].botmodule_class} #{botmodule} already registered, cannot re-register as #{kl}"
            end
          end
          @botmodules[kl] << botmodule
          @names_hash[botmodule.to_sym] = botmodule
          mark_priorities_dirty
        end