Lazily load classes through registry system - php

Question

I've been trying to optimise a backend system to make it just load classes as and when they're required, since there's no point loading every class when they're not required. I know we have the spl_autoload_register in PHP. At present I have my registry using __get and __set to access and set variables lazily, along with a loading function to add new classes to the registry as an object.
class registry {
public function __set($index, $value){
if(!isset($this->$index)){
$this->vars[$index] = $value;
} else {
die("The variable ".__CLASS__."->".$index." is already in use and cannot be redefined.");
}
}
public function __get($index){
if(isset($this->vars[$index])){
return $this->vars[$index];
} else if(isset($this->$index)){
return $this->$index;
} else {
$debug_backtrace = debug_backtrace();
$callee = next($debug_backtrace);
die("The variable \$".__CLASS__."->".$index." does not exist!");
}
}
public function load($class){
if(isset($class) && !empty($class) && file_exists('/_class/'.$class.'.class.php')){
include_once('/_class/'.$class.'.class.php');
$this->$class = new $class();
if(is_object($this->$class)){
} else {
die('Not found!');
}
}
} else if(isset($class) && !empty($class)){
die('The class `'.$class.'` does not exist!');
}
}
}
The above works great, at the moment, so all I need to do is the following:
$registry = new registry();
$registry->load('router');
$registry->load('mysql');
$registry->load('settings');
//etc
However, to make it use everything as and when needed, say settings doesn't appear on every page, I thought I could just change the __get section of the class as follows:
public function __get($index){
if(isset($this->vars[$index])){
return $this->vars[$index];
} else if(isset($this->$index)){
return $this->$index;
} else if($this->load($index)){ // additional line
return $this->$index; // additional line
} else {
$debug_backtrace = debug_backtrace();
$callee = next($debug_backtrace);
die("The variable \$".__CLASS__."->".$index." does not exist!");
}
}
However, all I keep getting now is Notice: Undefined property: registry::$settings in ... which is the if(is_object($this->$class)){ line, which I do not understand as it works normally via the function route as outlined previously, so an object success gets created through the current method, but not in the new one. Even as basic as the below, the same error appears (and hi there appears in the browser`):
class settings {
function __construct(){
echo 'hi there!';
}
}
I know I'm probably missing something very small, but an extra pair of eyes may help :o)

Answer 1

Seems I forgot to return the class via the load function :o(