Method transformItems

examples/demo.php:3031–3031

* @template T * @param array $items * @param callable(T): T $fn * @return array */

(array $items, callable $fn)

     * @return array<T>
     */
    public function transformItems(array $items, callable $fn): array { return $fn(); }

    /** @param \Closure(User): string $fn */
    public function mapUsers(\Closure $fn): array { return []; }