2 years ago

They have a really functional, Javascript-y taste: $sum = collect($numbers) ->filter(fn (int $x) => $x > 10) ->map(fn (int $x) => $x * 2) ->sum(); Another remarkable aspect of Laravel is custom collections. Let’s say we’re working on an investment portfolio application where we have transactions and holdings.

Fortunately, in Laravel, we can write a custom collection for a model: namespace App\Collections; use App\Models\Transaction; use Illuminate\Database\Eloquent\Collection; class TransactionCollection extends Collection { public function weightedPricePerShare(): float { if ($this->sum('quantity') === 0.00) { return 0; } $sumOfProducts = $this ->sum(fn (Transaction $transaction) => $transaction->quantity * $transaction->price_per_share ); return $sumOfProducts / $this->sum('quantity'); }}

The last step is to instruct Laravel to actually use this class whenever we're creating a new collection from Transaction models: namespace App\Models; use App\Collections\Transaction\TransactionCollection; use Illuminate\Database\Eloquent\Factories\HasFactory; class Transaction extends Model { use HasFactory; public function newCollection(array $models = []): TransactionCollection { return new TransactionCollection($models); }}

When the context of your function is a lot of model it’s a good indicator of a custom collection.