Question

When i add a node to a tree, i store its parent address (i thought so) in it:

-- Client --
$parent = new Node();
$child = new Node();
$parent->add($child)

-- Class Node --
function add($child) {
    $this->setParent(&$this);
    $this->children[] = $child;
}

function setParent($ref_parent) {
    $this->ref_parent = $ref_parent;
}

But when i try to echo $child->ref_parent, it fails on “Catchable fatal error: Object of class Node could not be converted to string…”, i use & cos i don’t want to store parent object in its child, but seems don’t work, any idea?

Answer 1

No, no, no. You can’t break down to such low level concepts like memory addresses in PHP. You can’t get a memory address of a value. $this and other objects are always passed by reference, so the object doesn’t get copied. At least in PHP5.