    # File lib/rack/cascade.rb, line 19
        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