creditCard property
Matches common credit card numbers (Visa, MasterCard, Amex, Discover).
Implementation
static final RegExp creditCard = RegExp(
r'^(?:4[0-9]{12}(?:[0-9]{3})?' // Visa
r'|5[1-5][0-9]{14}' // MasterCard
r'|3[47][0-9]{13}' // Amex
r'|6(?:011|5[0-9]{2})[0-9]{12})$', // Discover
);