To retrieve the first child element with a specified tag name

This example uses the [xml_node->extractone] method to retrieve the first "date" element from the "month" node. 

Code

var(aMonth = xml('<month>
    <data>
        <name>March</name>
        <date type="lastDay">31</date>
    </data>
    <date>4</date>
    <date>11</date>
    <date>16</date>
    <date>23</date>
    <date>30</date>
</month>') )

$aMonth->extractone('date')

Result

<date>4</date>