qwurx [shmem] ~ > perl -MO=Deparse,-x,-p
{
    my $debug = 0;
    if ($debug) {
        warn "debug set\n";
    }
}
__END__
{
    (my $debug = 0);
    if ($debug) {
        warn("debug set\n");
    }
}
__DATA__
(<Ctrl>D pressed)
- syntax OK
qwurx [shmem] ~ > perl -MO=Deparse,-x,-p
{
    sub debug () { 0 }
    if (debug) {
        warn "debug set\n";
    }
}
__END__
sub debug () { 0 }
{
    '???';
}
__DATA__
(<Ctrl>D pressed)
- syntax OK