array_assoc

array_assoc.php

<?php 

/**
 * Go from $scores to $result without using any loops!
 */
$scores = [
    ["player_id" => 3, "name" => "player #1", "score" => 150, "bonus" => 200],
    ["player_id" => 4, "name" => "player #2", "score" => 120, "bonus" => 100],
];

$result = collect([
    3 => ["name" => "player #1", "score" => 350],
    4 => ["name" => "player #2", "score" => 220],
]);

function array_assoc($callback, $value)
{
    return array_reduce(array_map($callback, $value), function($assoc, $row)
    {
        [$key, $value] = $row;
        $assoc[$key] = $value;

        return $assoc;
    }, []);
}

$result = array_assoc(function ($data) {
    return [$data["player_id"], [
        "name"  => $data["name"],
        "score" => $data["score"] + $data["bonus"],
    ]];
}, $scores);

<?php
$scores = [
    ['player_id' => 3, 'name' => 'player #1', 'score' => 150, 'bonus' => 200],
    ['player_id' => 4, 'name' => 'player #2', 'score' => 120, 'bonus' => 100],
];

$result = array_map(function ($item) {
    return ['name' => $item['name'], 'score' => $item['score'] + $item['bonus']];
}, array_column($scores, null, 'player_id'));