On Sat, Nov 25, 2017 at 9:12 AM, Jennifer <jennifer@xxxxxxxxxxxxxxxxxxxx> wrote: > I'm using PHP 7.1 now and just changed some code to use the Null > Coalesce Operator, like so: > > $ua = sanitize($_SERVER['HTTP_USER_AGENT']) ?? null; > You must use the ?? operator on the array access before passing it to your sanitize() function. $ua = sanitize($_SERVER['HTTP_USER_AGENT'] ?? null); Cheers, David