Interface: \Conifer\Twig\HelperInterface

Easily define custom functions to add to Twig by implementing this interface

Example

Define a class that implements this interface (typically in a lib file
in your theme):
```php
// my-project-theme/lib/MyProject/Twig/AnimalTwigHelper.php
namespace MyProject\Twig;
use Conifer\Twig\HelperInterface;
class AnimalTwigHelper implements HelperInterface {
  public function get_functions() : array {
return [
  'list_animals' => function() { return ['cat', 'dog', 'fox']; },
];
  }
  public function get_filters() : array {
return [
  'speak' => [$this, 'speak'],
];
  }
  public function speak(string $animal) {
return [
  'dog' => 'woof',
  'cat' => 'meow',
][$animal] ?? 'o hai';
  }
}

Add the functions/filters to your Site in your callback config:

// functions.php
use MyProject\Twig\AnimalTwigHelper;
$site->configure(function() {
  // ...
  $this->add_twig_helper(new AnimalTwigHelper());
});

Finally, call it from your Twig:

{# call our custom Twig function to get the list of animals #}
{% for animal in list_animals() %}
  {# what does the fox say?? #}
  <p>The {{ animal }} says: "{{ animal | speak }}!"</p>
{% endfor %}

This will output:

<p>The dog says: "woof!"</p>
<p>The cat says: "meow!"</p>
<p>The fox says: "o hai!"</p>

```