#[Cast]

Applies a cast to a constructor parameter during hydration (get()) and serialization (set()).

Syntax

use StdOut\SimpleDataObjects\Attributes\Cast;

#[Cast(new SomeCast(...))]
public readonly SomeType $property,

Example

use StdOut\SimpleDataObjects\Attributes\Cast;
use StdOut\SimpleDataObjects\Casts\DateTimeCast;
use StdOut\SimpleDataObjects\Casts\BooleanCast;

class EventData extends BaseData
{
    public function __construct(
        public readonly string $name,

        #[Cast(new DateTimeCast('Y-m-d'))]
        public readonly DateTime $startsAt,

        #[Cast(new BooleanCast)]
        public readonly bool $isPublic,
    ) {}
}

$event = EventData::from([
    'name'     => 'PHP Conf',
    'startsAt' => '2025-06-15',    // string → DateTime on hydration
    'isPublic' => 'yes',           // string → true on hydration
]);

$event->toArray()['startsAt']; // '2025-06-15' (DateTime → string on serialization)
$event->toArray()['isPublic']; // true

Constraints

• Only one #[Cast] per parameter is allowed.
• Cannot be combined with #[DataCollection] or #[Flatten] on the same parameter.

Built-in Casts

See Built-in Casts → for the full list.

Custom Casts

Implement CastsValue:

use StdOut\SimpleDataObjects\Contracts\CastsValue;

final class UpperCaseCast implements CastsValue
{
    public function get(mixed $value): ?string
    {
        return $value === null ? null : strtoupper((string) $value);
    }

    public function set(mixed $value): ?string
    {
        return $value === null ? null : strtoupper((string) $value);
    }
}

See Custom Casts →.