    # File lib/action_controller/caching/actions.rb, line 139
            def initialize(controller, options = {}, infer_extension=true)
              if infer_extension and options.is_a? Hash
                request_extension = extract_extension(controller.request)
                options = options.reverse_merge(:format => request_extension)
              end
              path = controller.url_for(options).split('://').last
              normalize!(path)
              if infer_extension
                @extension = request_extension
                add_extension!(path, @extension)
              end
              @path = URI.unescape(path)
            end