Build, test, and debug regular expressions
Matches strings containing 8 to 10 consecutive digits followed by exactly one non-letter, non-whitespace character (e.g., a symbol like #, -, or !). Intended for simple phone number validation, though note it requires a trailing special character after the digits, so a plain number like '12345678' will not match. With the g, m, and i flags, it can find all phone-like patterns across multiple lines of text.