in reply to Properly indented using HTML::Tiny

In the past I have used CGI::Pretty (part of CGI) to do something similar. Very useful when debugging tables. Not exactly what you're asking for though.

This CGI::Pretty code more-or-less duplicates your HTML::Tiny sample code: 

#!/usr/bin/perl
use strict;
use warnings;
use diagnostics;
use CGI::Pretty qw(-oldstyle_urls -no_xhtml);

my $q = CGI::Pretty->new();

print $q->start_html(-title => 'Sample page');
print $q->h1({-class => 'main'}, 'Sample page');
print $q->p('Hello, World');
print $q->p({-class => 'detail' }, 'Second para' );
print $q->end_html();

[download]
Output is: 
<!DOCTYPE html
        PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
         "http://www.w3.org/TR/html4/loose.dtd">
<html lang="en-US"><head><title>Sample page</title>
</head>
<body>

<h1 class="main">
        Sample page
</h1>
<p>
        Hello, World
</p>
<p class="detail">
        Second para
</p>

</body>
</html>

[download]

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