* @license http://opensource.org/licenses/MIT MIT */ declare(strict_types=1); namespace Ramsey\Collection; /** * This class contains the basic implementation of a collection that does not * allow duplicated values (a set), to minimize the effort required to implement * this specific type of collection. * * @template T * @extends AbstractCollection */ abstract class AbstractSet extends AbstractCollection { public function add(mixed $element): bool { if ($this->contains($element)) { return false; } // Call offsetSet() on the parent instead of add(), since calling // parent::add() will invoke $this->offsetSet(), which will call // $this->contains() a second time. This can cause performance issues // with extremely large collections. For more information, see // https://github.com/ramsey/collection/issues/68. parent::offsetSet(null, $element); return true; } public function offsetSet(mixed $offset, mixed $value): void { if ($this->contains($value)) { return; } parent::offsetSet($offset, $value); } }