- var_dump: documentation ( source)
<?php
$_GETO['complr'] = 'complr';
$_GETO['complr'] = 'complc';
$reunion_url = 'reunion_url';
$course_url = 'course_url';
var_dump(isset($_GETO['complr'], $_GETO['complc']));
list($voiture, $bus) = (isset($_GETO['complr'], $_GETO['complc'])) ? [$_GETO['complr'], $_GETO['complc']] : [$reunion_url, $course_url];
echo $voiture;
echo "\n";
echo $bus;