Visitor pattern


package OpenBSD::PackingElement;
sub do_stuff {}

package OpenBSD::PackingElement::FileBase;
sub do_stuff 
{
       my $self = shift;
       print "Any file: ", $self->fullname(), "\n";
}

package OpenBSD::PackingElement::Manpage;
sub do_stuff 
{
       my $self = shift;
       print "Man page: ", $self->fullname(), "\n";
}

$plist = OpenBSD::PackingList->fromfile("f");
$plist->visit('do_stuff');