I'm trying to add a new <student> node with attibute id="1003" after the <student> element with id='1001'. Here is the xml structure:

<?xml version="1.0" encoding="utf-8" ?>
<University>
    <students>
        <student id="1000"/>
        <student id="1001"/>
        <student id="1002"/>
    </students>
</University>

[download]

I'm using XML::LibXML module and wrote the following snippet: 

#!/usr/bin/perl

use XML::LibXML;

$parser = XML::LibXML->new();
$doc    = $parser->parse_file('student.xml');

$query  = '//student';

for my $ele ($doc->findnodes($query)){
    my $attr_text=$ele->getAttribute('id');
    if($attr_text eq '1001'){
        $new_ele=$doc->createElement('student');
        $new_ele->setAttribute('id','1003');
        $doc->insertAfter($new_ele,$ele);

        last;
    }
        
}

open(TESTFILE,">result.xml");
print TESTFILE $doc->toString;
close(TESTFILE);

[download]

But I'm getting the following run-time error:

NOT_FOUND_ERR

I'm still a novice in perl.Can you please explain the error message and tell me how to resolve it?

In reply to NOT_FOUND_ERR in insertAfter() by kingsaint

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