laravel collection keyby

1$collection = collect([
2    ['product_id' => 'prod-100', 'name' => 'Desk'],
3    ['product_id' => 'prod-200', 'name' => 'Chair'],
4]);
5
6$keyed = $collection->keyBy('product_id');
7
8$keyed->all();
9
10/*
11    [
12        'prod-100' => ['product_id' => 'prod-100', 'name' => 'Desk'],
13        'prod-200' => ['product_id' => 'prod-200', 'name' => 'Chair'],
14    ]
15*/

1$collection = collect([1, 2, 3, 4]);
2
3$filtered = $collection->filter(function ($value, $key) {
4    return $value > 2;
5});
6
7$filtered->all();
8
9// [3, 4]

1$item = collect();
2$item->push($product);