Using array_unshift() to Insert One or More Elements at the Beginning of an Array

Purpose: int array_unshift(array &$array, mixed $var, ...) inserts one or more elements at the beginning of an array. The inserted elements are treated as a whole, preserving their order, and numeric keys are reindexed starting from zero while string keys remain unchanged.

Parameters:

array : The input array to be modified.

var : One or more variables to prepend to the array.

Return value: The new number of elements in the array after the operation.

Example:

<?php
$queue = array("orange", "banana");
array_unshift($queue, "apple", "raspberry");
print_r($queue);
?>

Output:

Array
(
    [0] => apple
    [1] => raspberry
    [2] => orange
    [3] => banana
)