    # File lib/action_controller/caching.rb, line 172
          def expire_action(options = {})
            return unless perform_caching
            if options[:action].is_a?(Array)
              options[:action].dup.each do |action|
                expire_fragment(url_for(options.merge({ :action => action })).split("://").last)
              end
            else
              expire_fragment(url_for(options).split("://").last)
            end
          end