Greetings,

I'm branching out from working with HTML::TreeBuilder::XPath and HTML::Element which I am comfortable with. I am now trying to streamline some existing scripts by using XML::LibXML and XMLL::Element instead since that seems to allow transformation between various instances of XML more easily.

Or maybe not. There are some differences but by and large everything I have tried has gone well, and the parts I have refactored seem to run more quickly, except now I have become stumped by the error produced on line 19 in the script below, "XML::LibXML::Node::addSibling() -- nNode is not a blessed SV reference". How can I get past that and add a node? 

#!/usr/bin/perl

use XML::LibXML;
use XML::Element;

use strict;
use warnings;

# produces the following error:
# XML::LibXML::Node::addSibling() -- nNode is not a blessed SV referen
+ce ...

my $html = XML::LibXML->load_xml( IO => *DATA{IO} );

foreach my $dd ($html->findnodes('//dd[*/*/a[@class="f"]]')) {
    if (my $f = $dd->find('./*/*/a[@class="f"]/@href')) {
        print qq(F=$f\n);
    my $cc = XML::Element->new('dd');
    $cc->push_content('foo');
    $dd->addSibling($cc);    # this line fails
    }
}

print $html->toString,"\n";

exit(0);

__DATA__
<html><body>
<dl>
 <dd><details><summary>Example</summary>
  <dl>

   <dd><details><summary>one 
    <a href="http://localhost/s1" class="s">0</a>
    <a href="http://localhost/f1" class="f">0</a>
   </summary></details></dd>

   <dd><details><summary>two
    <a href="http://localhost/s2" class="s">1</a>
    <a href="http://localhost/f2" class="f">1</a>
   </summary></details></dd>

   <dd><details><summary>three
    <a href="http://localhost/s3" class="s">2</a>
    <a href="http://localhost/f3" class="f">2</a>
   </summary></details></dd>

  </dl></details>
 </dd>
</dl>
</body></html>

[download]

The script successfully selects a specific set of dd elements below but cannot add a sibling to any of them, at least not the ways I've tried so far. I've tried quite a few permutations and variations on the theme, too.

In reply to XML::LibXML::Node::addSibling() -- nNode is not a blessed SV reference ... by mldvx4

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