You just need to setup a DATA block and pass through filehandle => *DATA to HTML::Template 
#!/usr/bin/perl
use warnings; use strict;
use HTML::Template;
#------------
package Page;

use base 'HTML::Template';

sub new {
  my $self = shift;
  my %args = @_;

  $self->SUPER::new(%args);
}
#------------
package main;

my $template = Page->new(filehandle => *DATA)
   || die "Unable to open template";
$template->param(orb => 'world');
print $template->output;
__DATA__
hello <TMPL_VAR orb>

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In reply to Re: Converting code to use DATA filehandle instead of external templates by snoopy
in thread resolved: Converting code to use DATA filehandle instead of external templates by Spidy

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