#!/usr/bin/perl

use Template;

my $tt = Template->new;

my $template = <<"HERE";
<a[% IF url %] href="[% url %]"[% END %][% IF active %] class="active"[% END %]>
HERE

$tt->process( 
    \$template, 
    { url => 'http://www.example.com', active => 1 } 
    );

$tt->process( 
    \$template, 
    { url => 'http://www.example.com', active => 0 } 
    );