Self Executing functions in PHP5.3?

I was trying to borrow some programing paradigms from JS to PHP (just for fun). Is there a way of doing:

$a = (function(){
  return 'a';
})();

I was thinking that with the combination of use this can be a nice way to hide variables JS style

$a = (function(){
    $hidden = 'a';
    return function($new) use (&$hidden){
        $hidden = $new;
        return $hidden;
    };
})();

right now I need to do:

$temp = function(){....};
$a = $temp();

It seems pointless...