Views render the data produced by an action.

Views are implemented by subclassing the View class. But in most scenarios this is overkill. Usually you will use Twig templates with HotMelt (which are implemented by the TemplateView class behind the scenes).

To use a template view, place a Twig template file in the site templates directory (Site/Templates) and specify its name when declaring a route, e.g. for an index template:

<?php
\HotMelt\Route::add('/^\/$/', 'MySite\\Site::index', 'Index.html');

If you want to configure Twig, e.g. by adding filters or functions, you can access the Twig environment used by HotMelt with HotMelt\TemplateView::twig():

<?php
$twig = \HotMelt\TemplateView::twig();
$twig->addFilter(new \Twig_SimpleFilter('currency_format', function ($string) {
    return number_format(floatval($string), 2, ',', '.').' €';
}));