PHP Sadness... Callbacks as arguments

class.php

<?php

class c {
  public $f;
  public function __construct() { 
    $this->f = function() { echo 'coucou'; };
  }
}

// Note: "public $f = function() {...}" is a syntax error...

$c = new c;

// Works (displays "coucou")
$f = $c->f;
$f();

// Doesn't work (syntax error)
$c->f();

// Of course, doesn't work either...
($c->f)();