This function accepts a credit card number and, optionally, a code for a credit card name. If a Name code is specified, the number is checked against card-specific criteria,
then validated with the Luhn Mod 10 formula. Otherwise it is only checked against the formula. It can be used for Visa, Mastercard, Amex, Discover, Diners Club and JCB
Form processing program. A trimmed-down version of the popular Phorm script, Phorm Jr. has just email, acknowledgement and text log capabilities, but with the same security and
error-handling features of its big brother.