Testing the absolute() function in the aggregate version.
>>>>templates/test.tpl
<?xml version="1.0" ?>
<opt:root>
{@vars is absolute($vars)}
{@vars.v1}
{@vars.v2}
</opt:root>
>>>>data.php
$view->vars = array(
'v1' => 5,
'v2' => -5
);
>>>>expected.txt
OUTPUT
>>>>result.txt
5
5