class Lang extends ArrayAccess
{
    private $_langs = [];
    public function offsetSet($offset, $value) {
        if ($offset) {
            $this->_langs[] = $value;
        } else {
            $this->_langs[$offset] = $value;
        }
    }
    public function offsetExists($offset) {
        return isset($this->_langs[$offset]);
    }
    public function offsetUnset($offset) {
        unset($this->_langs[$offset]);
    }
    public function offsetGet($offset) {
        return isset($this->_langs[$offset]) ? $this->_langs[$offset] : null;
    }
}