Christian Opitz

<?php
abstract class package_class
{
    private function __inPackage($class) {
        $self = get_class($this);
        return strpos($class, $self) === 0;
    }

    public function __call($method, $arguments) {
            $backtrace = debug_backtrace();
            $class = $backtrace[2]['class'];

        if ($this->__inPackage($class)) {
                call_user_func_array(array($this, $method), $arguments);
            }
    }

    public function __get($var) {
        $backtrace = debug_backtrace();
        $class = $backtrace[1]['class'];

        if ($this->__inPackage($class)) {
            return $this->$var;
        }
    }
}

class some_package_class extends package_class
{
    protected $string2 = ' World';

    protected function output($string1) {
        echo $string1;
    }
}

class some_package_class_hook
{
    public function output(some_package_class $instance, $string1) {

        $instance->output($string1);

        echo $instance->string2;
    }
}

$class = new some_package_class();
$hook = new some_package_class_hook();
//Output "Hello World"
$hook->output($class, 'Hello');