PHP Ds\Queue clear() Function

The Ds\Queue::clear() Function in PHP is used to clear all of the elements from a Queue instance. This function just clears the instance without deleting it.

Syntax:

void public Ds\Queue::clear ( void )

Parameters: This function does not accepts any parameters.

Return Value: This function does not returns any value.

Below programs illustrate the Ds\Queue::clear() function in PHP:

Program 1:

PHP

<?php

// Declare new Queue
$q = new \Ds\Queue();

// Add elements to the Queue
$q->push("One");
$q->push("Two");
$q->push("Three");

echo "Initial Queue: \n";
// Display the Queue
print_r($q);

// clear the Queue
$q->clear();

echo "\nQueue after clearing:\n";
print_r($q);

?>

Output:

Initial Queue: 
Ds\Queue Object
(
    [0] => One
    [1] => Two
    [2] => Three
)

Queue after clearing:
Ds\Queue Object
(
)

Program 2:

PHP

<?php

// Declare new Queue
$q = new \Ds\Queue();

// Add elements to the Queue
$q->push("Geeks");
$q->push("for");
$q->push("Geeks");

echo "Initial Queue: \n";
// Display the Queue
print_r($q);

// clear the Queue
$q->clear();

echo "\nQueue after clearing:\n";
print_r($q);

?>

Output:

Initial Queue: 
Ds\Queue Object
(
    [0] => Geeks
    [1] => for
    [2] => Geeks
)

Queue after clearing:
Ds\Queue Object
(
)

Reference: http://php.net/manual/en/ds-queue.clear.php