public function add($key, $value, array $options=[]) {
		$options = array_merge(self::$defaults, $options);
		
		if ($this->attributes === null) {
			$this->attributes = new AttributesObject();
		}
		
		$this->validator->claimUsedFields([$key], Validator::OBJECT_CONTAINER_ATTRIBUTES, $options);
		
		$this->attributes->add($key, $value);
	}