Test, validate and match regular expressions
Matches dates in DD/MM/YYYY format where the day can be 1-31 (with optional leading zero), month can be 1-12 (with optional leading zero), and year is exactly four digits. Useful for parsing European-style date formats in user input or text documents. Note that it validates the pattern structure but not actual calendar validity (e.g., 31/02/2023 would match).