Silex - Twig_Error_Syntax: The function "path" does not exist

Question

According to the Silex documentation:

Symfony provides a Twig bridge that provides additional integration between some Symfony2 components and Twig. Add it as a dependency to your composer.json file.

I include the following in my composer.json file:

{
    "require": {
        "silex/silex": "1.*",
        "twig/twig": ">=1.8,<2.0-dev",
        "symfony/twig-bridge": "2.3.*"
    }
}

I register the TwigServiceProvider() like so:

$app->register(new Silex\Provider\TwigServiceProvider(), array(
    'twig.path' => __DIR__ . '/views'
));

I'm attempting to use the twig path() method like so:

<a href="{{ path('logout') }}">Log out</a>

The error I get is as follows:

Twig_Error_Syntax: The function "path" does not exist

Why am I getting this error?

• I have tried switching around versions to check if it is a version issue
• One google groups comment suggested 'registering' the twig bridge provider, but this doesn't exist
• I don't want to have to use: app.url_generator.generate in all my templates instead

---

A temporary solution I have found:

Ensure The UrlGeneratorServiceProvider() is registered:

$app->register(new UrlGeneratorServiceProvider());

Create a new function for twig for path():

$app['twig']->addFunction(new \Twig_SimpleFunction('path', function($url) use ($app) {
    return $app['url_generator']->generate($url);
}));

I shouldn't have to do this!! How can I get this working properly?

Answer 1

Hopefully this will help future viewers as many have posted this question without a solid answer, so here is one.

It is literally that you need UrlGeneratorServiceProvider() registered

$app->register(new UrlGeneratorServiceProvider());

Also, as umpirsky mentions in the comments, you need symfony/twig-bridge installed via composer.

You do not need to add your own function. You need both the TwigServiceProvider() and the UrlGeneratorServiceProvider() registered before loading your twig template. This isn't easily apparent from the documentation.

Answer 2

I too had to create a new function for twig for path(), but I improved it a bit to handle a variable number of arguments to allow passing arrays in the twig template:

$app['twig']->addFunction(new \Twig_SimpleFunction('path', function(...$url) use ($app) {
   return call_user_func_array(array($app['url_generator'], 'generate'), $url);
}));

Answer 3

Four easy steps.

1. Create the loader
2. Create the twig object.
3. Create you custom function
4. Add to the Twig object.

    use Twig\Environment;
    use Twig\TwigFunction;
    use Twig\Loader\FilesystemLoader;

    $loader = new FilesystemLoader('/twig/templates');
    $twig = new Environment($loader, []);

    $function = new TwigFunction('url', function () { return 'MyURL'; });
    $twig -> addFunction($function);