package ThreatNet::Filter::Null;
=pod
=head1 NAME
ThreatNet::Filter::Null - ThreatNet Filter to discard all messages
=head1 DESCRIPTION
The default C<ThreatNet::Filter> object returns true for all messages
passed to its C<keep> method, and can thus be used as a logical "true"
filter object if needed.
C<ThreatNet::Filter::Null> is a utility class which provides the logical
opposite of this. Calls to the C<keep> method for Null filter objects
B<always> return false.
Its the bit bucket of the ThreatNet Filter world.
=head1 METHODS
Methods are as for the parent L<ThreatNet::Filter> class.
=cut
use strict;
use Params::Util '_INSTANCE';
use base 'ThreatNet::Filter';
use vars qw{$VERSION};
BEGIN {
$VERSION = '0.20';
}
sub keep {
_INSTANCE($_[1], 'ThreatNet::Message') ? '' : undef;
}
1;
=pod
=head1 SUPPORT
All bugs should be filed via the bug tracker at
L<http://rt.cpan.org/NoAuth/ReportBug.html?Queue=ThreatNet-Filter>
For other issues, or commercial enhancement and support, contact the author
=head1 AUTHORS
Adam Kennedy E<lt>adamk@cpan.orgE<gt>
=head1 SEE ALSO
L<http://ali.as/threatnet/>, L<ThreatNet::Filter>
=head1 COPYRIGHT
Copyright (c) 2005 Adam Kennedy. All rights reserved.
This program is free software; you can redistribute
it and/or modify it under the same terms as Perl itself.
The full text of the license can be found in the
LICENSE file included with this module.
=cut