note 124288 added to function.empty

$a = '' or '0' or false or 0 or null or what else.. <?php $a = function(){ $arr = ['', 0, '0', false, null]; return $arr[rand(0,4)]; }; $a = $a(); if (! $a) { var_dump($a); } if (empty($a)) { var_dump($a); } ?> results : all passed so, what is the difference between empty function and "!" operator? ---- Server IP: 208.43.231.9 Probable Submitter: 185.85.3.168 (proxied: 176.43.222.185) ---- Manual Page -- http://php.net/manual/en/function.empty.php Edit -- https://master.php.net/note/edit/124288 Del: integrated -- https://master.php.net/note/delete/124288/integrated Del: useless -- https://master.php.net/note/delete/124288/useless Del: bad code -- https://master.php.net/note/delete/124288/bad+code Del: spam -- https://master.php.net/note/delete/124288/spam Del: non-english -- https://master.php.net/note/delete/124288/non-english Del: in docs -- https://master.php.net/note/delete/124288/in+docs Del: other reasons-- https://master.php.net/note/delete/124288 Reject -- https://master.php.net/note/reject/124288 Search -- https://master.php.net/manage/user-notes.php