You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: cascade.rb
    path of file: ./repos/ferrocarril/mruby-gems/vendor/ruby/2.6.0/gems/rack-2.0.7/lib/rack
    
    the code of the file until where you have to start completion: module Rack
  # Rack::Cascade tries a request on several apps, and
    
    def call(env)
      result = NotFound

      last_body = nil

      @apps.each do |app|
        # The SPEC says that the body must be closed after it has been iterated
        # by the server, or if it is replaced by a middleware action. Cascade
        # replaces the body each time a cascade happens. It is assumed that nil
        # does not respond to close, otherwise the previous application body
        # will be closed. The final application body will not be closed, as it
        # will be passed to the server as a result.
        last_body.close if last_body.respond_to? :close

        result = app.call(env)
        last_body = result[2]
        break unless @catch.include?(result[0].to_i)
      end

      result
    end

    def add(app)
      @has_app[app] = true
      @apps << app
    end

    def include?(app)
      @has_app.include? app
    end

    alias_method :<<, :add
  end