session destroy does not work wamp code example

Example: session_destroy not working

//After using session_destroy(), the session is destroyed behind the scenes. For some reason this doesn't affect the values in $_SESSION, which was already populated for this request, but it will be empty in future requests.

//You can manually clear $_SESSION if you so desire ($_SESSION = [];).
 <?php
 $_SESSION = [];
 session_unset();
 session_destroy();
?>