The SplDoublyLinkedList::isEmpty() function is an inbuilt function in PHP which is used to check whether the doubly linked list is empty or not.
Syntax:
php
php
bool SplDoublyLinkedList::isEmpty( void )Parameters: This function does not accepts any parameters. Return Value: This function returns True if doubly linked list is empty, False otherwise. Below programs illustrate the SplDoublyLinkedList::isEmpty() function in PHP: Program 1:
<?php
// Declare an empty SplDoublyLinkedList
$list = new \SplDoublyLinkedList;
// Use isEmpty function
$res = $list->isEmpty();
var_dump($res);
// Use SplDoublyLinkedList::push() function to
// add elements to the SplDoublyLinkedList
$list->push(1);
$list->push(2);
$list->push(3);
$list->push(8);
$list->push(5);
// Use isEmpty function
$res = $list->isEmpty();
var_dump($res);
?>
Output:
Program 2:
bool(true) bool(false)
<?php
// Declare an empty SplDoublyLinkedList
$list = new \SplDoublyLinkedList;
// Use isEmpty function
$res = $list->isEmpty();
var_dump($res);
// Use SplDoublyLinkedList::add() function to
// add elements to the SplDoublyLinkedList
$list->add(0, 30);
$list->add(1, 20);
$list->add(2, 30);
$list->add(3, "Geeks");
$list->add(4, 'G');
// Use isEmpty function
$res = $list->isEmpty();
var_dump($res);
?>
Output:
Reference: https://www.php.net/manual/en/spldoublylinkedlist.isempty.phpbool(true) bool(false)