func extractID(s string, ln *line) (string, error) {
	tokens := strings.Split(s, sharp)

	l := len(tokens)

	if l < 2 {
		return "", nil
	}

	if l > 2 {
		return "", fmt.Errorf("multiple IDs are specified [file: %s][line: %d]", ln.fileName(), ln.no)
	}

	return strings.Split(tokens[1], dot)[0], nil
}
func extractID(s string, ln *line) (string, error) {
	tokens := strings.Split(s, sharp)

	l := len(tokens)

	if l < 2 {
		return "", nil
	}

	if l > 2 {
		return "", fmt.Errorf("multiple IDs are specified [file: %s][line: %d]", ln.fileName(), ln.no)
	}

	return strings.Split(tokens[1], dot)[0], nil
}
func extractID ( s string , ln * line ) ( string , error ) { tokens := strings . Split ( s , sharp ) l := len ( tokens ) if l < 2 { return " " , nil } if l > 2 { return " " , fmt . Errorf ( " " , ln . fileName ( ) , ln . no ) } return strings . Split ( tokens [ 1 ] , dot ) [ 0 ] , nil }
// extractID extracts and returns an ID.
extractID extracts and returns an ID .