It's hard to envisage what the HTML you are dealing with looks like from the code snippet. It would help us provide an answer if you could include sample HTML with the sample code. It would be even better if it were wrapped up like this:

use strict;
use warnings;
use HTML::TreeBuilder;

my $str = do {local $/; <DATA>};

get_birthday ($str);

sub get_birthday {
  my $content = shift;
  my $tree = HTML::TreeBuilder->new;
  $tree->parse($content);
  my @elements = $tree->look_down('_tag' => 'a');
  for my $element (@elements) {
    my $class_tag = $element->attr_get_i('class') || '';
    if ($class_tag eq "mailtext") {
      my $subject = $element->as_trimmed_text();
      my $subject_url = $element->attr_get_i('href');
      print "<a href='$subject_url'>$subject</a>\n";
      print $element->look_up('_tag' => 'a')->all_attr() . "\n";
    }
  }
}

__DATA__
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<html lang="en">
<head>
</head>
<body>
<p><a>Metalink<a class="mailtext" href='http://erewhon.com'>Erewhon</a
+></a></p>
 </body>
</html>

[download]

Interestingly this generates a 'Use of uninitialized value' warning in line 16 then prints:

<a href='http://erewhon.com'>Erewhon</a>
5/8

[download]

which looks like a stringified hash to me. That may be a clue, but without something resembling your actual HTML it's a bit hard to say.

DWIM is Perl's answer to Gödel

In reply to Re: look_up() in HTML::Element Not Traversing As Expected by GrandFather
in thread look_up() in HTML::Element Not Traversing As Expected by initself

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