(PHP 5 >= 5.3.0, PHP 7, PHP 8)
SplDoublyLinkedList::setIteratorMode — Sets the mode of iteration
modeThere are two orthogonal sets of modes that can be set:
SplDoublyLinkedList::IT_MODE_LIFO (Stack style)SplDoublyLinkedList::IT_MODE_FIFO (Queue style)SplDoublyLinkedList::IT_MODE_DELETE (Elements are deleted by the iterator)SplDoublyLinkedList::IT_MODE_KEEP (Elements are traversed by the iterator)
The default mode is: SplDoublyLinkedList::IT_MODE_FIFO | SplDoublyLinkedList::IT_MODE_KEEP
The direction of iteration can not be changed for SplStack and
SplQueue classes, it is always SplDoublyLinkedList::IT_MODE_FIFO.
Trying to modify it will result in a RuntimeException being thrown.
Returns the different modes and flags that affect the iteration.