What are the best practices for implementing a template-based processing system in PHP?

Template-based processing systems in PHP can help separate the presentation layer from the business logic, making code more maintainable and reusable. To implement this, create a template file with placeholders for dynamic content, then use PHP to replace these placeholders with actual data before rendering the final output. Utilizing a templating engine like Twig can also simplify the process and provide additional features like template inheritance and caching.

// Load the Twig library
require_once 'vendor/autoload.php';

// Set up Twig environment
$loader = new Twig_Loader_Filesystem('templates');
$twig = new Twig_Environment($loader);

// Define data to be passed to the template
$data = [
    'title' => 'Welcome to my website!',
    'content' => 'Lorem ipsum dolor sit amet, consectetur adipiscing elit.'
];

// Render the template with the data
echo $twig->render('index.html', $data);