Not to be a stick in the mud, but please remember that not all credit cards are 16 digits long. For instance, AMEX is 15 digits (4-6-5 or s/(.{4})(.{6})(.{5})/$1 $2 $3/) and some VISA cards are 13 digits (4-3-3-3 or s/(.{4})(.{3})(.{3})(.{3})/$1 $2 $3 $4/).

On a side note, you can use Business::CreditCard to tell what type of credit card you are dealing with as well as whether or not the credit card's checksum is valid.

Hope this helps.

antirice    
The first rule of Perl club is - use Perl
The ith rule of Perl club is - follow rule i - 1 for i > 1

In reply to Re: Simple formatting question for credit card number by antirice
in thread Simple formatting question for credit card number by Anonymous Monk

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