generating xml

Hi I've managed to inclue elements with php to xml file, but all the things i add come in one line. Like so: <one nr="4"><name>Patrik</name><sex>M</sex></one><one nr="5"><name>Patrik</name><sex>M</sex></one> Is there a way to add "\n" (new line) characters or something to my script so that it is better for humans to find possible bugs or something... Here is my script: //////////////////////////////////////////////// <?php class Test{

      function Test(){
      	$name="Patrik";
        $sex="M";
      	$xmlfile=$_SERVER["DOCUMENT_ROOT"]."/xml/test.xml";
        $xmlstr=join('', file($xmlfile));
        if (!$dom= domxml_open_mem($xmlstr)){
        	die ('couldn\'t open the file.' );
        }
        $ones=$dom->get_elements_by_tagname("one");
        $last_one=$ones[count($ones)-1];
        $last_nr=$last_one->get_attribute("nr");
        // here i found the attr nr of last one, so new ones nr=last_nr++

        $root = $dom->document_element();
        $new_one=$dom->create_element("one");
        $new_one->set_attribute("nr", $last_nr+1);
        $new_name=$dom->create_element("name");
        $new_sex=$dom->create_element("sex");
        $new_name->set_content($name);
        $new_sex->set_content($sex);
        $new_one->append_child($new_name);
        $new_one->append_child($new_sex);
        $root->append_child($new_one);

        $dom->dump_file($_SERVER["DOCUMENT_ROOT"]."/xml/test.xml" ,false ,true);
        $xmlstr = $dom->dump_mem();
        echo "<pre>";
        echo htmlentities($xmlstr);
        echo "<pre>";

      }

} $test=new Test(); ?> ////////////////////////////////////////