parse

# File actionpack/lib/action_controller/request.rb, line 646
    def parse(key, value)
      self.string = key
      @top, @parent = result, nil

      # First scan the bare key
      key = scan(KEY_REGEXP) or return
      key = post_key_check(key)

      # Then scan as many nestings as present
      until eos?
        r = scan(BRACKETED_KEY_REGEXP) or return
        key = self[1]
        key = post_key_check(key)
      end

      bind(key, value)
    end