Higher order collection message

Collections also provide support for "higher order messages", which are short-cuts for performing common actions on collections. This example calculates the price per group of products on an offer.

$offer = [
        'name'  => 'offer1',
        'lines' => [
            ['group' => 1, 'price' => 10],
            ['group' => 1, 'price' => 20],
            ['group' => 2, 'price' => 30],
            ['group' => 2, 'price' => 40],
            ['group' => 3, 'price' => 50],
            ['group' => 3, 'price' => 60]
        ]
];
 
$totalPerGroup = collect($offer['lines'])->groupBy->group->map->sum('price');