laravel mapWithKeys方法 【返回指定键值】

$collection = collect([
    [
        'name' => '哼',
        'department' => '测试',
        'email' => '965643796@qq.com'
    ],
    [
        'name' => '哈',
        'department' => '测试',
        'email' => '965643796@qq.com'
    ]
]);

$keyed = $collection->mapWithKeys(function ($item) {
    return [$item['email'] => $item['name']];
});

$keyed->all();

/*结果
[
    '965643796@qq.com' => 'John',
    '965643796@qq.com' => 'Jane',
]
*/