Problem with object references...

[bu22]

I'll try to put this as simply as possible...

I have a class that contains an array of objects. This class has an addObject() method which simply does the following: -

// array object method
function addObject(&$object) {
$this->_objects[] =& $object;
}

It also has a method to list the object names: -

// array object method to list names
function listNames() {
foreach ($this->_objects as $object) {
echo($object->getName()."<br>");
}
}

Each object is added to the array object when it is created: -

// object constructor
function Object(&$arrayObject, $name) {
$this->name = $name;
$this->arrayObject =& $arrayObject;
$this->_arrayObject->addObject($this);
}

Each object also has a name property with the standard get/set functions: -

function getName() {
return $this->name;
}
function setName($name) {
$this->name = $name;
}

OK... here's the problem. When I run the following code: -

$arr = new $arrayObject();
$obj1 = new Object($arr, 'apples');
$obj2 = new Object($arr, 'bananas');
$arr->listNames();

I get the expected output: -

apples
bananas

But if I run the following code: -

$arr = new $arrayObject();
$obj1 = new Object($arr, 'apples');
$obj2 = new Object($arr, 'bananas');
$obj2->setName('oranges');
$arr->listNames();

I still get: -

apples
bananas

instead of the desired: -

apples
oranges

It seems there's a reference problem here somewhere but I have failed to spot it so far! :-(

Any help is appreciated.

[ahundiak]

Make sure you use the reference operator when creating the object.

$object =& new Object(...);

Otherwise you wll end up with two copies.

[bu22]

Thanks! That worked, but I don't understand why it works.

Fair enough, if I create a reference to an already existing object, I'd use the reference operator to prevent a duplicate being made: -

$objectRef =& object;

But when using the "new" operator, isn't there only ONE object created (the one on the left side of the " = " ?.....

$object = new Object;

What am I creating a reference to? The created object? Surely thats the one returned from the "new" call...

I'm Confused!

[ahundiak]

It's the assignement that generates the copy.

$object1 = $object2;

Will always make a copy of whatever is one the right side.

It is confusing. PHP5 is supposed to be better.