use strict;
use warnings;
use HTML::Template;

my @items = map {{item => $_}} qw(first second third fourth);
my $template = HTML::Template->new(filehandle => *DATA);

$template->param(items => \@items);
print $template->output();

__DATA__
    <TMPL_IF name="items">
    <ul><TMPL_LOOP name="items">
       <li><TMPL_VAR name="item"></li></TMPL_LOOP>
    </ul></TMPL_IF>

##</code><code>##

    
    <ul>
       <li>first</li>
       <li>second</li>
       <li>third</li>
       <li>fourth</li>
    </ul>