The Ds\Queue::isEmpty() Function in PHP is used to whether a particular Queue instance is empty or not. It returns True if the Queue is empty otherwise it returns False.
Syntax:
bool public Ds\Queue::isEmpty ( void )
Parameters: This function does not accepts any parameters.
Return Value: This function returns a boolean value based on whether this Queue is empty or not. It returns True if the Queue is empty otherwise it returns False.
Below programs illustrate the Ds\Queue::isEmpty() Function in PHP:
Program 1:
<?php   // Declare new Queue $q = new \Ds\Queue();   // Initially Queue is Empty var_dump($q->isEmpty());   // Add elements to the Queue $q->push("One"); $q->push("Two"); $q->push("Three");   // Check again if the Queue // is Empty var_dump($q->isEmpty());   ?> |
bool(true) bool(false)
Program 2:
<?php   // Declare new Queue $q = new \Ds\Queue();   // Initially Queue is Empty var_dump($q->isEmpty());   // Add elements to the Queue $q->push("Geeks"); $q->push("for"); $q->push("Geeks");   // Check again if the Queue // is Empty var_dump($q->isEmpty());   ?> |
bool(true) bool(false)
Reference: http://php.net/manual/en/ds-priorityqueue.isempty.php
