Question

My question is pretty simple: How can I write a function once and make it available globally across every Twig template I have in a bundle?

Answer 1

Try to reproduce more or less the following class in Bundle\Twig\Extensions

class LabelsExtension extends \Twig_Extension
{

   function getName()
   {
      return 'labels';
   }

   function getFunctions()
   {
      return array(
          'perso_label' => new \Twig_Function_Method($this, 'persoLabel')
      );
   }
   function persoLabel($value)
   {
      if ($value == 1) return 'HI';
   }
}

Then in your config.yml or services.yml, you need to have something like this:

services:
    twig.extension.mynamespace.labels:
        class: Namespace\Bundle\Twig\Extension\LabelsExtension
        tags:
            - { name: 'twig.extension' }

So now you can call it in any template with {{ perso_label(1) }} or whatever.