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Editorial Team
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Asked: 2026-05-27T08:30:42+00:00

What is the opposite of XPath’s last() function, to select the "first" (apparently, there

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What is the opposite of XPath’s last() function, to select the "first" (apparently, there is no first()) result from query?

Or, how would I mimic it?

Update

Maybe the problem is with my specific example using ancestors and context.

document.html

<div id="holder" special-header="We have a special header here">
    <div class="element" special-header="And this is even more specific">
        <p id="interested">Content, content</p>
    </div>
</div>

script.php

$doc = new DOMDocument;
$doc->loadHTMLFile('document.html');
$contextNode = $document->getElementById('interested');

/* first try */
$first = $xpath->query('//ancestor::*[@special-header][1]', $contextNode);
echo $first->getAttribute('special-header'); // result == "We have a special header here" intended == "And this is even more specific"

/* second try */
$one = $xpath->query('//ancestor::*[@special-header][last()]', $contextNode); // in case it starts from "first found ancestor" and descends
echo $one->getAttribute('special-header'); // same result as before..

Trying with position()=1 I get the same result again.

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1 Answer

  1. Editorial Team

    The problem is that the meaning of the expression //ancestor::*[@special-header] is rather vague, because // forces searching from the root node.

    The solution is to remove the // at the beginning of the expressions.

    BTW, your code is actually not working =). Here is the corrected version:

    $html = <<<HTML
<div id="holder" special-header="We have a special header here">
    <div class="element" special-header="And this is even more specific">
        <p id="interested">Content, content</p>
    </div>
</div>
HTML;

$doc = new DOMDocument();
$doc->loadHTML($html);
$contextNode = $doc->getElementById('interested');
$xpath = new DOMXpath($doc);

$first = $xpath->query('ancestor::*[@special-header][1]',
                       $contextNode) -> item(0);
echo $first->getAttribute('special-header') . "\n";

$one = $xpath->query('ancestor::*[@special-header][last()]',
                     $contextNode)-> item(0);
echo $one->getAttribute('special-header') . "\n";

    Results in:

    C:\>\php\php.exe dom_games.php
And this is even more specific
We have a special header here
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