sub do_some_stuff {
  $debug .= qq(<h5 style="color:#c33;">SUB: do_some_stuff</h5><div style="margin-left:20px;">);
  
  my $abc = qq(The foo bar boogie);
  (my $xyz = $abc) =~ s!foo!bar!;
  $xyz = &do_something_else($xyz); #pretend &do_some_other_stuff is basically the same as &do_some_stuff
  
  $debug .= qq(XYZ: $xyz);
  $debug .= qq(</div><h5 style="color:#c33;">ENDSUB: do_some_stuff</h5>);
  
  return($xyz);
}

my $output	= $template->output;
$output .= qq(--Debug Info-- <pre>$debug</pre>);
return($output);