<?php

// creating a twig filter Extension
class MyTwigFilters extends Twig\Extension\AbstractExtension
{
    public function getName()
    {
        return 'MyFilters';
    }
    
    public function getFilters()
    {
        return [
            new Twig\TwigFilter('to_int', [$this, 'toInt']),
        ];
    }
    
    public function toInt($value)
    {
        return (int) $value;
    }
}

$templates = [
    'filter-template' => 'Filtered value: {{ null|to_int }}',
];

echo '- template content:' . PHP_EOL;
echo $templates['filter-template'] . PHP_EOL;

$loader = new Twig\Loader\ArrayLoader($templates);
$twig = new Twig\Environment($loader);
$twig->addExtension(new MyTwigFilters());

echo '- rendered template:' . PHP_EOL;
echo $twig->render('filter-template');

- template content:
Filtered value: {{ null|to_int }}
- rendered template:
Filtered value: 0

• Creating and using Twig functions
• Creating and using own Twig features with Twig tags
• Lint your json files and strings

PHP 8.2, Laminas MVC 3.2, Symfony 5.2, Laravel 8.28, PHPUnit 9.5, Doctrine ORM 2.8