class TOC extends Genome {
    public $lot = [];
    public function __construct(?string $content) {}
    public function content(): ?string {}
    public function count(): int {}
    public function of(): ?string {}
}

Hook::set('page.t-o-c', function () {
    $t = new TOC($this->content);
    return $t->count() > 1 ? $t : null;
});

<?php if ($v = $page->{'t-o-c'}): ?>
  <?= $v->of; ?>
  <?= $v->content; ?>
<?php else: ?>
  <?= $page->content; ?>
<?php endif; ?>