Allright, I'll do it myself:

$xmlreader = XMLReader::open('xml_file.xml');
$indent = 0;
while ($xmlreader->read() !== FALSE)
{
    switch ($xmlreader->nodeType)
    {
        case XMLReader::ELEMENT:
            echo str_repeat("\t", ($xmlreader->isEmptyElement ? $indent : $indent++)), '[element]: ', $xmlreader->name, "\n";
            break;
        case XMLReader::TEXT:
            echo str_repeat("\t", $indent), $xmlreader->value, "\n";
            break;
        case XMLReader::END_ELEMENT:
            echo str_repeat("\t", --$indent), '[end element]: ', $xmlreader->name, "\n";
            break;
    }
}