How to render a tree in Twig

Question

I would like to render a tree with an undetermined depth (children of children of children, etc.). I need to loop through the array recursively; how can I do this in Twig?

Answer 1

If you're running PHP 5.4 or higher, there is a wonderful new solution (as of May 2016) to this problem by Alain Tiemblo: https://github.com/ninsuo/jordan-tree.

It's a "tree" tag that serves this exact purpose. Markup would look like this:

{% tree link in links %}
    {% if treeloop.first %}
{% endif %}

    

        {{ link.name }}
        {% subtree link.sublinks %}
    

    {% if treeloop.last %}
{% endif %}
{% endtree %}