PHP array_is_list() Function

The array_is_list() function is an inbuilt function in PHP that is used to check whether a given array is a list or not. If the given array will be a list if the key of the array contains consecutive numbers from 0 to count($arr)-1.

Syntax: 

bool array_is_list(array $array)

Parameters: This function accepts one parameter $array that will check for the list.

Return Value: This function returns true if the given array is a list and false otherwise.

Note: This function returns true on an empty array.

Example 1:

<?php

$arr1 = array("10", "20", "30", "40", "50");

var_dump(array_is_list($arr1));

$arr2 = array(
    'Geeks'  => "HTML", 
    'GFG'  => "CSS", 
    'Geek'  => "JavaScript", 
    'G4G' => "PHP"
);

var_dump(array_is_list($arr2));

?>

Output:

bool(true)
bool(false)

Example 2:

<?php

var_dump(array_is_list([]));

var_dump(array_is_list(array(
    "10" => "Geeks", 
    "20" => "GeeksforGeeks",
    "30", 
    "40", 
    "50"
)));

var_dump(array_is_list(
    array(5, 10, 15, 20, 25)
));

?>

Output:

bool(true)
bool(false)
bool(true)

Note: This function works on PHP 8.1.0 or higher versions.

Reference: https://www.php.net/manual/en/function.array-is-list.php