public function id($object)
    {
        if ($provider = $this->nearestForClass(get_class($object), 'id')) {
            return call_user_func($provider, $object);
        }
        return '';
    }
public function id($object)
    {
        if ($provider = $this->nearestForClass(get_class($object), 'id')) {
            return call_user_func($provider, $object);
        }
        return '';
    }
{@inheritdoc}

@param object $object
@return int|string