I have a function(this is exactly how it appears, from the top of my file):
Another possible reason for getting that error is that your function has the same name as another PHP built-in function. For example,
function checkdate($date){
$now=strtotime(date('Y-m-d H:i:s'));
$tenYearsAgo=strtotime("-10 years", $now);
$dateToCheck=strtotime($date);
return ($tenYearsAgo > $dateToCheck) ? false : true;
}
echo checkdate('2016-05-12');
where the checkdate function already exists in PHP.