I'm currently using XML::Twig to handle processing of XML documents, and have run into a snag regarding setting a default twig handler. We want to use the "_default_" twig handler to print a warning about unrecognized elements for development (and validation) purposes, but XML::Twig doesn't seem to be calling the "_default_" twig handler at all.

I've created a minimal test program and test XML document that illustrates the problems we're having: 

#!/usr/bin/perl -w

# twigtest.pl

use strict;
use XML::Twig;

my $t = new XML::Twig(
        TwigHandlers => {
            'download' => \&tag_download,
            '_default_' => \&tag__default,
            }
        );
if (!($t->safe_parsefile('test.xml'))) {
    warn("Error: Test XML had processing errors: $@\n");
}

# Handles the <download> tag.
sub tag_download {
    my ($t,$elt) = @_;
    
    print("Found a <download>!\n");
    
    $t->purge();
}

# Handles any unrecognized tag.
sub tag__default {
    my ($t,$elt) = @_;
    
    print("Unrecognized tag: <".$elt->gi().">!\n");
    
    $t->purge();
}

[download]
Here's the test XML document (named "test.xml"): 
<?xml version="1.0" ?>
<download>
  <oops/>
</download>

[download]
The output from running "./twigtest.pl" is: 
Found a <download>!

[download]
which seems to indicate that tag__default isn't being called by XML::Twig.

The version of Perl we're using is 5.005_03, haven't yet had a chance to try it on 5.6.1. XML::Twig version is 2.02. Am I doing something wrong? Has anybody else experienced this problem?

- Zoogie

In reply to Problems with default twig handler in XML::Twig by Zoogie

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