Call __get() on protected properties with -> operator?

My team is using lazyloading techniques to load sub-objects from our database. To do this we're using the magic __get() method and making a database call. All of our properties are protected so the __get method gets called from outside of the object but our issue is that it doesn't get called from within the object without using $this->__get($name);

So my question is: Is it possible to force __get() to be called with the normal chaining operator even from within the object?

If I want to chain object access I currently have to do:

$this->__get('subObject')->__get('subObject')->__get('subObject')

Is it possible to write the following, but have it still call __get()?

$this->subObject->subObject->subObject

Thanks, Jordan

Solution

Jordan,

PHP won't call the __get() method unless the property is inaccessible—either because it doesn't exist, or because of visibility. When the property is hidden from the calling scope the __get() method is called because the property is inaccessible. When the property is referenced and is available to the calling scope, __get() will never fire. (It's not meant to fire for an existing/accessible property.)

To work around this you have to rename your internal properties. Either prefix them with a name, underscore, or store them in a common array parameter with a special name. The following is somewhat contrived, but it ought to demonstrate how you can deal with this situation.

class MyObject {
   protected $lazyloads = array();

   protected function lazyload($relation) {
     // ...
   }

   public function __get($key) {
     if (isset($this->lazyloads[$key]) {
       return $this->lazyloads[$key];
     } else {
       return $this->lazyload($key);
     }
   }
}

See: http://www.php.net/manual/language.oop5.overloading.php#object.get