public static function mset($chunk, array $keys, $value) {
        $head = $chunk;
        $last = count($keys)-1;
        foreach($keys as $id => $key) {
            if ($last == $id) {
                if (is_null($value)) {
                    unset($chunk->$key);
                } else {
                    $chunk->$key = $value;
                }
            } else {
                $chunk->$key = isset($chunk->$key)? $chunk->$key : new stdClass();
                $chunk = $chunk->$key;
            }
        }
        return $head;
    }