Build, test, and debug regular expressions
Matches 10-digit North American Numbering Plan (NANP) phone numbers with optional hyphen separators, e.g. 212-586-1234 or 2125861234. Enforces modern NANP rules: area code starts with 2-9 and second digit 0-8, lookaheads block N11 service codes (911, 411) and repeated digits in the area code, and the exchange code must start with 2-9 and not be N11. Useful for validating US/Canadian phone numbers without country code or parentheses.