Object and reference problem

Someone, have a go at this! I have encountered a very troublesome problem, which I don't see how to solve in an elegant way, since PHP doesn't support method overloading. Suppose my class is, kind of a tree, like: class A { var $children; function A() {

       $this->children = array();

} // I want this to accept both objects and strings etc. // IE. mixed function add($child) {

      $this->children[] = $child;

} function printStuff() {

      foreach ($this->children as $child) {
         if (is_object($child))
            $child->printStuff();
         else
           echo $child;
      }

} } Now this is fine: 1 $obj1 = new A(); 2 $obj2 = new A(); 3 $obj1->add("Something"); 4 $obj2->add(", something else"); 5 $obj1->add($obj2); 6 $obj1->printStuff(); and prints out "something, something else" But if I swap lines 4 and 5 it only prints out "something". Obviously, the add method of $obj1 only receives a copy of $obj2, and if I try to add something to $obj2 afterwards, even thought it's supposed to be hooked with $obj1, it will "disappear". For objects only I could solve this with declaring add() like: function add(&$child) {

    $this->children[] = $child;

} So it receives a reference of the object, but then I can't add a string (fatal error, cannot pass string as reference), or an integer or double, for that matter! And I really don't want to use different method names! I don't have full control over the reference stuff in PHP, does anyone know how I can fix this? Or a workaround? Thanx!