Hello, {{ name  *(instead {{ name }})*

message body

$twig->registerUndefinedFunctionCallback(function ($name) {

   if (function_exists($name)) {
    return new Twig_Function_Function($name);
   }

   return false;
});

try {

   $twig->parse($twig->tokenize($template));


} catch (Twig_Error_Syntax $e) {

    // here you are

}