(PHP 5 >= 5.3.0, PHP 7) Constructs a new empty queue

(PHP 5 >= 5.1.0, PHP 7) Returns if an iterator can be created fot the current entry.

(PHP 5 >= 5.0.0, PHP 7) Seek to position public

(PHP 5 >= 5.1.0, PHP 7) Seek to a position

(PHP 5 >= 5.1.0, PHP 7) End children public

(PHP 5 >= 5.1.0, PHP 7) Notify an observer

(PHP 5 >= 5.1.2, PHP 7) Tells if the file is a link

(PHP 5 >= 5.3.0, PHP 7) Peeks at the node from the top of the heap

(PHP 5 >= 5.3.0, PHP 7) Rewind iterator back to the start

(PHP 5 >= 5.3.0, PHP 7) Return current node index