public function allOf(string $name): array
    {
        $oid = AttributeType::attrNameToOID($name);
        $attribs = array_filter($this->_attribs,
            function (AttributeTypeAndValue $tv) use ($oid) {
                return $tv->oid() == $oid;
            });
        return array_values($attribs);
    }