# File lib/chef/knife/role_show.rb, line 37
      def run
        @role_name = @name_args[0]

        if @role_name.nil?
          show_usage
          ui.fatal("You must specify a role name")
          exit 1
        end

        role = Chef::Role.load(@role_name)
        output(format_for_display(config[:environment] ? role.environment(config[:environment]) : role))
      end