code: func (p *parser) skipWhitespace() bool {
  	i := p.i
  	for i < len(p.s) {
  		switch p.s[i] {
  		case ' ', '\t', '\r', '\n', '\f':
  			i++
  			continue
  		case '/':
  			if strings.HasPrefix(p.s[i:], "/*") {
  				end := strings.Index(p.s[i+len("/*"):], "*/")
  				if end != -1 {
  					i += end + len("/**/")
  					continue
  				}
  			}
  		}
  		break
  	}
  
  	if i > p.i {
  		p.i = i
  		return true
  	}
  
  	return false
  }
docs: // skipWhitespace consumes whitespace characters and comments.
  // It returns true if there was actually anything to skip.