use strict;
use CGI;
use HTML::Template;

my $q = CGI->new();
my $template = HTML::Template->new(
   filename  => 'some.tmpl',
   associate => $q,
);

# assign params to $template according to user input/validation

print $q->header, $template->output;

##</code><code>##

use strict;
my $q = My::CGI->new;
print $q->h1('hello world'),$/;

package My::CGI;
use base qw(CGI);
sub h1 { "<42>$_[1]</42>" }

##</code><code>##

perl -MCGI=foo -le "print foo{bar=>baz},qux"