my @action_tree = ( { test => sub { $_[0] >= 300 && $_[0] <= 400 },
                      action => sub { print "GUDNITES\n"; CORE::exit(0) } },
                    { test => sub { $_[0] >= 425 && $_[0] <= 500 },
                      action => sub { print "OHAI\n" } } );

while ( my $signal = <SIGNAL_SOURCE> )
{
    $_->{test}->($signal) && $_->{action}->() for @action_tree;
}