value) ? null : boolval($this->value); } public function set($value): bool { if ($value === 'false') $value = false; if ($value === 'null') $value = null; return parent::set(is_null($value) ? null : boolval($value)); } public static function applyFilter($query, $value) { parent::applyFilter($query, ($value === 'yes')); } }