// source: https://r.je/mvc-in-php.html
class Model {
    public $txt;
    public function __construct() {
        $this->txt = 'Hi world!';
    }        
}
class View {
    private $model;
    public function __construct(Model $model) {
        $this->model = $model;
    }
    public function output() {
        return '<h1>' . $this->model->txt .'</h1>';
    }
}
class Controller {
    private $model;
    public function __construct(Model $model) {
        $this->model = $model;
    }
}
$model = new Model();
$controller = new Controller($model);
$view = new View($model);
echo $view->output();