code: func normalizeFlowSpecOpValues(args []string) []string {
  	// Extracts keywords from the given args.
  	sub := ""
  	subs := make([]string, 0)
  	for _, s := range _regexpFlowSpecOperator.FindAllString(strings.Join(args, " "), -1) {
  		sub += s
  		if _regexpFlowSpecOperatorValue.MatchString(s) {
  			subs = append(subs, sub)
  			sub = ""
  		}
  	}
  
  	// RFC5575 says "It should be unset in the first operator byte of a
  	// sequence".
  	if len(subs) > 0 {
  		subs[0] = strings.TrimPrefix(subs[0], "&")
  	}
  
  	return subs
  }
docs: // Joins the given and args into a single string and normalize it.
  // Example:
  // args := []string{"  &  <=80", " tcp  != udp ", " =!   SA   & =U!  F", " =  is-fragment+last-fragment"}
  // fmt.Printf("%q", normalizeFlowSpecOpValues(args))
  // >>> ["<=80" "tcp" "!=udp" "=!SA" "&=U" "!F" "=is-fragment+last-fragment"]