与php刀片模板的codeigniter错误/不允许直接脚本访问

I have installed all the required component to use blade but am getting an error message when I run my code. here is my MY_Controller file

<?php
defined('BASEBATH') OR exit ('No direct script access allowed');

use Coolpraz\PhpBlade\PhpBlade;

class MY_Controller extends CI_Controller{
    protected $views = APPBATH. 'views';
    protected $cache = APPBATH. 'cache';
    protected $blade;

    public function __construct(){
        parent:: __construct();
        $this->$blade = new PhpBlade($this->$views, $this->$cache);
    }
}