PHP array_map_keys

array_map_keys.php

<?php

function array_map_keys(
    Closure $keys,
    Closure $values,
    array $array
): array {
    $output = [];

    foreach ($array as $value) {
        $output[$keys($value)] = $values($value);
    }

    return $output;
}

$input = [
    (object) [
        'id'    => 1,
        'color' => 'red',
        'item'  => 'apple',
    ],
    (object) [
        'id'    => 2,
        'color' => 'orange',
        'item'  => 'orange',
    ],
    (object) [
        'id'    => 3,
        'color' => 'white',
        'item'  => 'eggplant',
    ],
];

$output = array_map_keys(
    function($val) {
        return $val->id;
    },
    function($val) {
        return $val;
    },
    $input
);

/*
 * Array
 * (
 *     [1] => stdClass Object
 *         (
 *             [id] => 1
 *             [color] => red
 *             [item] => apple
 *         )
 *
 *     [2] => stdClass Object
 *         (
 *             [id] => 2
 *             [color] => orange
 *             [item] => orange
 *         )
 *
 *     [3] => stdClass Object
 *         (
 *             [id] => 3
 *             [color] => white
 *             [item] => eggplant
 *         )
 *
 * )
 */
print_r($output);

$output = array_map_keys(
    function($val) {
        return $val->id;
    },
    function($val) {
        return $val->color;
    },
    $input
);

/*
 * Array
 * (
 *     [1] => red
 *     [2] => orange
 *     [3] => white
 * )
 */
print_r($output);