package Regexp::Common::SEN;

use 5.10.0;

use strict;
use warnings;
no  warnings 'syntax';

use Regexp::Common qw /pattern clean no_defaults/;

our $VERSION = '2017060201';

=begin does_not_exist

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)

=end does_not_exist

pattern name   => [qw /SEN USA SSN -sep=-/],
        create => sub {
            my $sep = $_ [1] {-sep};
            "(?k:(?k:[1-9][0-9][0-9]|0[1-9][0-9]|00[1-9])$sep"   .
                "(?k:[1-9][0-9]|0[1-9])$sep"                     .
                "(?k:[1-9][0-9][0-9][0-9]|0[1-9][0-9][0-9]|"     .

=begin does_not_exist

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

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)})|(?!))/;

=end does_not_exist




=head1 NAME

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


 use Regexp::Common qw /SEN/;

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


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

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

=head2 C<$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 hyphen (C<->).
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 C<-sep=I<P>> is specified, the pattern I<P> is used as the
separator between the groups of numbers.

Under C<-keep> (see L<Regexp::Common>):

=over 4

=item $1

captures the entire SSN.

=item $2

captures the first group of digits (the area number).

=item $3

captures the second group of digits (the group number).

=item $4

captures the third group of digits (the serial number).


=head1 SEE ALSO

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

=head1 AUTHORS

Damian Conway and Abigail.


This package is maintained by Abigail S<(I<>)>.


Bound to be plenty.

For a start, there are many common regexes missing.
Send them in to I<>.


This software is Copyright (c) 2001 - 2017, Damian Conway and Abigail.

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

 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 License.               See the file COPYRIGHT.BSD.
 4) The MIT License.               See the file COPYRIGHT.MIT.