each

# File actionpack/lib/action_controller/rack_process.rb, line 185
    def each(&callback)
      if @body.respond_to?(:call)
        @writer = lambda { |x| callback.call(x) }
        @body.call(self, self)
      elsif @body.is_a?(String)
        @body.each_line(&callback)
      else
        @body.each(&callback)
      end

      @writer = callback
      @block.call(self) if @block
    end