code: func New(r io.Reader) (s *Scanner) {
  	s = &Scanner{}
  	s.r = bufio.NewReader(r)
  	s.Whitespace = datastructs.NewBitSet(256)
  	s.Error = func(err error) {
  		fmt.Fprintf(os.Stderr, "Scanner error: %s\n", err)
  	}
  	// initialize default with Whitespace variable
  	s.InitWhitespace(Whitespace)
  	s.token = make([]rune, MaxTokenLen)
  	s.tokenIdx = 0
  	return
  }
docs: // New creates a new scanner from reader