When dealing with arrays in PHP, checking for an index like if ($a['foo'])
throws a PHP warning.
There are two ways to avoid these warnings: one is using isset(), which checks the existance of an array index. The second one is empty(), which not only checks for the existence of the array index, but also that the value that contains is not empty (not NULL, 0, '' or FALSE).
Here are some console examples:
juampy@juampybox $ php -a
php > $a = array('foo' => 'asdfasd');
php >