code: func (s *SACKScoreboard) String() string {
  	var str strings.Builder
  	str.WriteString("SACKScoreboard: {")
  	s.ranges.Ascend(func(i btree.Item) bool {
  		str.WriteString(fmt.Sprintf("%v,", i))
  		return true
  	})
  	str.WriteString("}\n")
  	return str.String()
  }
docs: // Dump prints the state of the scoreboard structure.