code: func (l *Line) Capture() string {
  	if len(l.Comment) == 0 {
  		return ""
  	}
  	matches := placeholderRegexp.FindSubmatch(l.Comment)
  	if len(matches) < 2 {
  		return ""
  	}
  	return string(matches[1])
  }
docs: // Capture extracts the first placeholder value from the
  // comments.