Server : Apache System : Linux server1.cgrithy.com 3.10.0-1160.95.1.el7.x86_64 #1 SMP Mon Jul 24 13:59:37 UTC 2023 x86_64 User : nobody ( 99) PHP Version : 8.1.23 Disable Function : NONE Directory : /usr/share/perl5/vendor_perl/Business/ |
package Business::ISBN13; use strict; use base qw(Business::ISBN); use Business::ISBN qw(:all); use Data::Dumper; use subs qw( _checksum INVALID_COUNTRY_CODE INVALID_PUBLISHER_CODE BAD_CHECKSUM GOOD_ISBN BAD_ISBN ); use vars qw( $VERSION $debug ); use Carp qw(carp croak cluck); my $debug = 0; $VERSION = '2.06'; sub _max_length { 13 } sub _set_type { $_[0]->{type} = 'ISBN13' } sub _parse_prefix { my $isbn = $_[0]->isbn; # stupid workaround for 'Can't modify non-lvalue subroutine call' ( $isbn =~ /\A(97[89])(.{10})\z/g )[0]; } sub _set_prefix { croak "Cannot set prefix [$_[1]] on an ISBN-13" unless $_[1] =~ m/\A97[89]\z/; $_[0]->{prefix} = $_[1]; } sub _hyphen_positions { [ $_[0]->_prefix_length, $_[0]->_prefix_length + $_[0]->_group_code_length, $_[0]->_prefix_length + $_[0]->_group_code_length + $_[0]->_publisher_code_length, $_[0]->_checksum_pos, ] } # sub group { 'Bookland' } sub as_isbn10 { my $self = shift; return unless $self->prefix eq '978'; my $isbn10 = Business::ISBN->new( substr( $self->isbn, 3 ) ); $isbn10->fix_checksum; return $isbn10; } sub as_isbn13 { my $self = shift; my $isbn13 = Business::ISBN->new( $self->as_string ); $isbn13->fix_checksum; return $isbn13; } #internal function. you don't get to use this one. sub _checksum { my $data = $_[0]->isbn; return unless defined $data; my @digits = split //, $data; my $sum = 0; foreach my $index ( 0, 2, 4, 6, 8, 10 ) { $sum += substr($data, $index, 1); $sum += 3 * substr($data, $index + 1, 1); } #take the next higher multiple of 10 and subtract the sum. #if $sum is 37, the next highest multiple of ten is 40. the #check digit would be 40 - 37 => 3. my $checksum = ( 10 * ( int( $sum / 10 ) + 1 ) - $sum ) % 10; return $checksum; } 1; __END__ =head1 NAME Business::ISBN13 - work with 13 digit International Standard Book Numbers =head1 SYNOPSIS See L<Business::ISBN> =head1 DESCRIPTION See L<Business::ISBN> =head1 SOURCE AVAILABILITY This source is in Github. https://github.com/briandfoy/business--isbn =head1 AUTHOR brian d foy C<< <bdfoy@cpan.org> >> =head1 COPYRIGHT AND LICENSE Copyright (c) 2001-2013, brian d foy, All Rights Reserved. You may redistribute this under the same terms as Perl itself. =cut