/**
* Returns true if this list iterator has more elements when traversing the list in the backward direction.
* @return boolean
*/
public function next()
{
if ($this->hasNext()) {
$this->canRemove = true;
return $this->list->get(--$this->index);
} else {
throw new NoSuchElementException("Could not find element at index {$this->index}");
}
}
/**
* Injects a node into the current tree structure,
* such that the node at the specified index becomes
* a child of the injected node, and the injected node
* moves to the specified index in the receiver
* @param int $index
* @param TreeNodeInterface $node
*/
public function injectAt($index, TreeNodeInterface $node)
{
$node->insert($this->children->get($index));
$this->replaceAt($index, $node);
}
