Taking the time to re-read your requirements (sorry, I was making dinner for the kids when I last posted) I notice you want to do this for various header tags, so consider this:

td.html

<!DOCTYPE html>
<html>
  <head>
    <style>
     div.hammer {
       height: 100px;
     }
    </style>
  </head>
<body>
  <h2>Derp</h2>
  <p>Derp content here</p>
  <div class='hammer'>Sponsored by artisan hammers</div>
  <h3>Gerp</h3>
  <p>Gerp content here</p>
  <div class='hammer'>Sponsored by artisan hammers</div>
  <h4>Blerp</h4>
  <p>Blerp content here</p>
  </body>
</html>

[download]

Why the divs? to break up the content a little so when you construct your TOC that it'll be easy to visibly test.

td.pl

#!/usr/bin/perl
use strict;
use warnings;
use feature 'say';

use Mojo::DOM;
use Mojo::File;

my $path = Mojo::File->new('td.html');
my $html = $path->slurp;

my $dom = Mojo::DOM->new( $html );

#for each hr
foreach my $hr ( $dom->find('h2,h3,h4,h5,h6')->each ){
  # grab the text
  my $text  = $hr->text;
  my $class = $hr->text;
  # remove x.x.
  $class =~ s/\-?\d+\.\d+\. //g;
  # update the DOM
  $hr->replace("<h2 class='$class'>$text</h2>");
  
}
# display updated DOM 
say $dom;

[download]

Output.

<!DOCTYPE html>
<html>
  <head>
    <style>
     div.hammer {
       height: 100px;
     }
    </style>
  </head>
<body>
  <h2 class="Derp">Derp</h2>
  <p>Derp content here</p>
  <div class="hammer">Sponsored by artisan hammers</div>
  <h2 class="Gerp">Gerp</h2>
  <p>Gerp content here</p>
  <div class="hammer">Sponsored by artisan hammers</div>
  <h2 class="Blerp">Blerp</h2>
  <p>Blerp content here</p>
  </body>
</html>

[download]

Now all you need to do is read and understand the Mojo docs, adding a little bit of code to create a TOC, appending it after the body, or wherever is appropriate in your actual HTML.

In reply to Re: Calling sub-routine in regex by marto
in thread Calling sub-routine in regex by tonydunn

Title:
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