#!/usr/bin/env perl
use strict;
use warnings;
use HTML::HTML5::Parser;
use HTML::HTML5::Writer qw(DOCTYPE_XHTML1);
my $parser = 'HTML::HTML5::Parser'->new;
my $writer = 'HTML::HTML5::Writer'->new(markup => 'xhtml', doctype => DOCTYPE_XHTML1);
print $writer->document( $parser->load_html(IO => \*DATA) );
__DATA__
Some HTML
Here is some HTML