/**
* Create a filter iterator.
*
* @param Ingo_Storage $storage A storage object.
* @param array $filter A list of rules (classnames) to filter.
*
* @return Ingo_Storage_FilterIterator Filtered iterator.
*/
public static function create(Ingo_Storage $storage, array $filter = array())
{
$iterator = new static($storage->getIterator());
$iterator->setFilter($filter);
return $iterator;
}