Calling closure assigned to object property directly

Question

I would like to be able to call a closure that I assign to an object\'s property directly without reassigning the closure to a variable and then calling it. Is this possible

Answer 1

Updated:

$obj = new stdClass();
$obj->callback = function() {
     print "HelloWorld!";
};

PHP >= 7 :

($obj->callback)();

PHP >= 5.4 :

$callback = $obj->callback;  
$callback();