PHP5 overloading, cannot access protected property

[kaimeder]

hi everyone,

im using overloading, especially __get(), to simplify chaining of objects like this

$this->context->user->attributes->userID = 1; 

now i get this error-message:

"Fatal error: Cannot access protected property Radix_Context::$user in <file> on line <line>"

context has an protected attribute $user, so php should trigger __get() to dispatch this call but it doesn't! it tries to access the property directly which does not work.

on the other hand, this testcase works like a charm:

class OverloadingDispatcher
{
function __get($name)
    {
    return call_user_func(array($this , "get{$name}"));
    }
}


class Root extends OverloadingDispatcher
{
protected $a;

function __construct()
    {
    $this->a = new A();
    }

function getA()
    {
    return $this->a;
    }
}

class A extends OverloadingDispatcher
{
protected $b;

function __construct()
    {
    $this->b = new B();
    }

function getB()
    {
    return $this->b;
    }
}

class B extends OverloadingDispatcher
{
protected $c;

function __construct()
    {
    $this->c = new C();
    }

function getC()
    {
    return $this->c;
    }
}

class C
{
function sayHello()
    {
    echo 'hello world!';
    }
}

$r = new Root();
$r->a->b->c->sayHello(); 

i already sent this problem to the german mailinglist located at phpbar.de and johannes schlueter answered, stating that this procedure is absolutely normal.
php checks the properties visibility and than refuses to call the magic-overloading-functions.

anyone any hint?
thanks!
kai

[thr]

It is true, php checks for property visibility BEFORE it checks for overloading. Nothing u can do about it except use __call() instead and use them as method, ie:

$class1->class2()->class3()->class4()->class5()

[kaimeder]

k, i could understand this BUT why does the testcase work like a charm ???

[kaimeder]

*bump*

im using php5.1 RC1.
anyone any hint?

thanks,
kai

[stereofrog]

*bump*

You'll probably get your question answered quicker if you post a minimal code that doesn't work.

[kaimeder]

i tried to build a testcase with pretty much the same class-hierachy as in my non-working code but the bug does not appear, so i can't reproduce it....

i may post the complete code of my application but this is far too much ...

so ... rephrasing my question: is my problem at least _known_ to others? (using php5.1RC1)

yours,
kai

[kaimeder]

k, now i know the error.

you can't use __set() whiling chaining, only __get()-calls work ...

does NOT work:

$class1->class2->class3->foobar = 1; 

does work:

echo $class1->class2->class3->foobar; 

....
kai

[dagfinn]

you can't use __set() whiling chaining, only __get()-calls work ...

I assume you mean if you have an actual variable that's named the same as the virtual one you're trying to access. It seems to me it would be simpler to rename the real one to, say, $_var instead of $var;

[stereofrog]

I think it's a bug related to bug 28444.

You should submit a bugreport (seems it's not yet reported)

--reproduce code

class A {
	private $p;
	function __get($name){
		return $this->$name;
	}
	function __set($name, $value) {
		$this->$name = $value;
	}
}
class B {
	private $t;
	function __get($name){
		return $this->$name;
	}
	function __set($name, $value) {
		$this->$name = $value;
	}
}
$a = new A;
$b = new B;
$a->p = $b;
$b->t = "foo";

echo $a->p->t;
$a->p->t = "bar";
echo $a->p->t;

--expected result:

foobar

--actual result

foo
Fatal error: Cannot access private property A::$p in...

[kaimeder]

thats *exactly* what im meaning, thanks.
i've posted a bug-report using your code.

thanks!
kai

[stereofrog]

The testcase above works with last cvs.
kaimeder: thanks for help improving php

[Tanus]

This is a problem that's been affecting prado for quite a while.