Another strategy: 

use XML::LibXML;
my $d = XML::LibXML->new->parse_string(join "", <DATA>);
for my $dead ($d->findnodes(q{/opt/node[val = "2"]})) {
  $dead->unbindNode;
}
print $d->toString;

__END__
<opt>
  <node>
    <val>1</val>
  </node>
  <node>
    <val>2</val>
  </node>
  <node>
    <val>3</val>
  </node>
</opt>

[download]
which results in: 
<?xml version="1.0"?>
<opt>
  <node>
    <val>1</val>
  </node>
  
  <node>
    <val>3</val>
  </node>
</opt>

[download]

-- Randal L. Schwartz, Perl hacker
Be sure to read my standard disclaimer if this is a reply.

In reply to •Re: How to remove elements from XML data? by merlyn
in thread How to remove elements from XML data? by waxmop

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