Integrate Twig with CodeIgniter 4

I used Twig with Symfony and I really loved it. I now have a CodeIgniter project and I want to integrate Twig with it.

I installed the latest versions of CodeIgniter and Twig via Composer and and followed this tutorial but I believe the code in the tutorial is for CI v3.

Could anyone who has integrated Twig with CI v4 help me with the proper code please.

UPDATE

solution below!

Solution

I found the solution some time ago and I'm posting it in case some people stumble across the question.

First of all, all your controllers must extend BaseController; this controller is available by default when you install CodeIgniter 4.
Create a custom helper file and put in [project-name]/appstarter/app/Helpers.

IMPORTANT

the name of your helper must be [name]_helper.php or it will not work!

for example mine is called custom_helper.php

Create the following function in the custom helper you just created:

 use Twig\Environment;
 use Twig\Extension\DebugExtension;
 use Twig\Loader\FilesystemLoader;
 use Twig\TwigFilter;

 if (!function_exists('twig_conf')) {
     function twig_conf() {
         // the follwing line of code is the only one needed to make Twig work
         // the lines of code that follow are optional
         $loader = new FilesystemLoader('Views', '../app/');

         // to be able to use the 'dump' function in twig files
         $twig = new Environment($loader, ['debug' => true]);
         $twig->addExtension(new DebugExtension());

         // twig lets you create custom filters            
         $filter = new TwigFilter('_base_url', function ($asset) {
             return base_url() . '/' . $asset;
         });
         $twig->addFilter($filter);

         return $twig;
     }
 }

NOTE

before creating any custom filter, make sure Twig doesn't already has one built-in.

Now in the BaseController you'll find an empty array called $helpers. You must put the name of your custom helper in it. Mine is called custom_helper.php; so the code looks like this for me:
```
protected $helpers = ['custom'];
```

Just below the array you'll find the constructor for BaseController and this is where the Twig library will be initialized; by calling the function you created in your custom helper:

public function initController(RequestInterface $request, ResponseInterface $response, LoggerInterface $logger) {      
    parent::initController($request, $response, $logger);

    $this->twig = twig_conf();
}

Now you are good to go! To render your twig files in any controller:
```
return $this->twig->render('twig_name', $dataArray);
```