Chyba v kode

<?php

class bbb{
  private $a="aaa";
 
  public function read(){
    return $this->a;
  }
}

class aaa{
  private $a="bbb";
 
  public function __construct(){
    $bbb = new bbb();
  }
 
  public function read(){
    return $this->a;
  }
}


class main{
  private $a="main";
 
  private $instance;

  public function __construct(){
    $aaa = new aaa();
  }
 
  public function read(){
    return $this->a;
  }
}

$oop = new main();

echo $oop->aaa->read();

?>

class A {

public function render() {
   echo 'ahoj';
}

}

class B {

private $var;

public function __construct(A $objekt) { //parameter musí byť objekt triedy A
        $this->var = $objekt;
   }

}

$objekt = new B(new A);
$objekt->var->render(); //vypise ahoj