sub par11 { my $string = shift; my $sum = 0; for my $i (0 .. length ($string) - 1) { my $c = substr ($string, $i, 1); $sum += $c * (length ($string) - $i) } !($sum % 11) }

It's not clear whether this is the right checksum.

# http://www.google.nl/search?q=cache:8m1zKNYrEO0J:www.enschede.nl/nieuw/projecten/aanbesteding/integratie/pve%2520Bijlage%25207.5.doc+Sofi+nummer+formaat&hl=en&start=56&lr=lang_en|lang_nl&ie=UTF-8 pattern name => [qw /SEN Netherlands SoFi/], create => sub { # 9 digits (d1 d2 d3 d4 d5 d6 d7 d8 d9) # 9*d1 + 8*d2 + 7*d3 + 6*d4 + 5*d5 + 4*d6 + 3*d7 + 2*d8 + 1*d9 # == 0 mod 11. qr /([0-9]{9})(?(?{par11 ($^N)})|(?!))/; } ;

NAME

Regexp::Common::SEN -- provide regexes for Social-Economical Numbers.

SYNOPSIS 

 use Regexp::Common qw /SEN/;

 while (<>) {
     /^$RE{SEN}{USA}{SSN}$/    and  print "Social Security Number\n";
 }

DESCRIPTION

Please consult the manual of Regexp::Common for a general description of the works of this interface.

Do not use this module directly, but load it via Regexp::Common.

$RE{SEN}{USA}{SSN}{-sep}

Returns a pattern that matches an American Social Security Number (SSN). SSNs consist of three groups of numbers, separated by a hypen (-). This pattern only checks for a valid structure, that is, it validates whether a number is valid SSN, was a valid SSN, or maybe a valid SSN in the future. There are almost a billion possible SSNs, and about 400 million are in use, or have been in use.

If -sep=P is specified, the pattern P is used as the separator between the groups of numbers.

Under -keep (see Regexp::Common):

$1
captures the entire SSN.
$2
captures the first group of digits (the area number).
$3
captures the second group of digits (the group number).
$4
captures the third group of digits (the serial number).

HISTORY 

 $Log: SEN.pm,v $
 Revision 2.104  2008/05/23 21:30:09  abigail
 Changed email address

 Revision 2.103  2008/05/23 21:28:01  abigail
 Changed license

 Revision 2.102  2005/01/02 01:17:48  abigail
 - Removed 'use Carp', as we aren't using it.
 - Outcommented unused 'par11' function. Ought to be in _support.pm anyway.

 Revision 2.101  2004/06/09 21:52:14  abigail
 Force 2.101 version

 Revision 2.1  2004/06/09 21:50:14  abigail
 Initial checkin

SEE ALSO

Regexp::Common for a general description of how to use this interface.

AUTHORS

Damian Conway and Abigail.

MAINTAINANCE

This package is maintained by Abigail (regexp-common@abigail.be).

BUGS AND IRRITATIONS

Bound to be plenty.

For a start, there are many common regexes missing. Send them in to regexp-common@abigail.be.

COPYRIGHT

This software is Copyright (c) 2001 - 2008, Damian Conway and Abigail.

This module is free software, and maybe used under any of the following licenses: 

 1) The Perl Artistic License.     See the file COPYRIGHT.AL.
 2) The Perl Artistic License 2.0. See the file COPYRIGHT.AL2.
 3) The BSD Licence.               See the file COPYRIGHT.BSD.
 4) The MIT Licence.               See the file COPYRIGHT.MIT.