__get() and __set() can be private, but not __call(). Why?

[dagfinn]

Maybe my brain just isn't working and there's some obvious explanation for this, but for now I'm bewildered.

When I test, I find that __get() and __set() will intercept member variable access even if they're private or protected, but when I try to make __call() private, I get an error message. The examples in the PHP manual seem to reflect this difference.

Any ideas?

[stereofrog]

// 5.1.0

class A {
    private $priv_var;

    private function priv_func() {
        echo "func\n";
    }
    private function __call($m, $a) {
        echo "call $m\n";
    }
    private function __get($p) {
         return "get $p\n";
    }
}

$x = new A();

echo $x->not_really; // ok
echo $x->priv_var;   // ok

$x->not_really();  // ok
$x->priv_func();   // ERROR 

__call itself can be private, just like get and friends.

IIRC __get behaviour was changed in 5.1. In 5.0 only "missing" properties were forwarded to __get, as of 5.1 all "unresolvable" requests (undefs + access violations) are forwarded. __call seems still to use 5.0 semantics.

[dagfinn]

Thanks. Very interesting. I've now tested it in the 5.1.1 version I had lying around, and it seems __call() can be private in 5.1 but not 5.0. I can't find it in the change log, though.

It's a useful feature, so I'm not complaining.