https://www.php.net/manual/tr/recursiveiteratoriterator.getinneriterator.php
PHP: RecursiveIteratorIterator::getInnerIterator - Manual
phpmanual
https://www.php.net/manual/es/outeriterator.getinneriterator.php
PHP: OuterIterator::getInnerIterator - Manual
Devuelve el iterador interno para la entrada actual
phpmanual
https://www.php.net/manual/en/iteratoriterator.getinneriterator.php
PHP: IteratorIterator::getInnerIterator - Manual
Get the inner iterator
phpmanual