Example usage of the "Null Coalescing Assignment Operator"

index.php

<?php

$arr = [
    'a' => 'xyz',
    'b' => null,
    'c' => 0,
];

// Rather than writing:
//
// if (
//     ! isset($arr['x'])
//     || is_null($arr['x'])
// ) {
//     $arr['x'] = 0;
// }
//
// Or (better):
//
// if (empty($arr['x'])) {
//     $arr['x'] = 0;
// }
//
// Why not just use the power of the "Null Coalescing Operator"?

$arr['a'] = $arr['a'] ?? 0;

// Or even better, you can use the "Null Coalescing ``Assignment`` Operator".

$arr['b'] ??= 0;
$arr['c'] ??= 0;
$arr['d'] ??= 0;

print_r($arr);

// Output:
//
// Array
// (
//     [a] => xyz
//     [b] => 0
//     [c] => 0
//     [d] => 0
// )