Construtor de Regex

Match starts with, then literal '(', then optional, then digit (0-9), then quantified by {2}, then literal ')', then optional, then whitespace, then optional, then '9', then optional, then digit (0-9), then quantified by {4}, then '-', then optional, then digit (0-9), then quantified by {4}, then ends

1. ^start of input
2. \(escaped '('
3. ?optional
4. \ddigit (0-9)
5. {2}quantifier {2}
6. \)escaped ')'
7. ?optional
8. \swhitespace
9. ?optional
10. 9literal '9'
11. ?optional
12. \ddigit (0-9)
13. {4}quantifier {4}
14. -literal '-'
15. ?optional
16. \ddigit (0-9)
17. {4}quantifier {4}
18. $end of input