callback = $callback; } } #[ReturnTypeWillChange] public function __unserialize($data) {} // phpcs:enable public function __wakeup() { unset($this->callback); } #[ReturnTypeWillChange] public function current() { $value = parent::current(); if (is_callable($this->callback)) { $value = call_user_func($this->callback, $value); } return $value; } #[ReturnTypeWillChange] public function unserialize($data) {} }