public function __construct($name, Property $childType = null)
 {
     $this->childProperty = $childType;
     parent::__construct($name);
     // Must be traversable
     $this->addRequirement(new IsType(IsType::TYPE_ARRAY));
 }
 public function __construct(Model $model, $name = null)
 {
     $this->model = $model;
     if (!isset($name)) {
         $name = $model->getName();
     }
     parent::__construct($name);
 }