[php: <=>] Spaceship operator on PHP 7. #php

spaceship_operator.php

/**
 * Spaceship operator.
 * @link https://qiita.com/Hiraku/items/62821d7d0e7af1ac211e
 * @link https://teratail.com/questions/61222#reply-97259
 */

// 多次元配列の Diff
$arr1 = [
    ['flag' => 2, 'status' => 25],
    ['flag' => 64, 'status' => 25],
];
$arr2 = [
    ['flag' => 122, 'status' => 25],
    ['flag' => 2, 'status' => 25],
    ['flag' => 88, 'status' => 25],
];

$compare = function ($x, $y) {
    return $x['flag'] <=> $y['flag'] ?: $x['status'] <=> $y['status'];
};

var_dump(array_merge(
    array_udiff($arr2, $arr1, $compare),
    array_udiff($arr1, $arr2, $compare)
));