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

I played around with domi27's idea and came up with this. I made a nested array as my tree, ['link']['sublinks'] is null or another array of more of the same.

Templates

The sub-template file to recurse with:

{% for link in links %}
    

        {{ link.name }}
        {% if link.sublinks %}
            

                {% include "includes/menu-links.html" with {'links': link.sublinks} %}
            
        {% endif %}
    
{% endfor %}

Then in the main template, call this (kind of redundant 'with' stuff there):

    {% include "includes/menu-links.html" with {'links':links} only %}

Macros

A similar effect can be achieved with macros:

{% macro menu_links(links) %}
    {% for link in links %}
        

            {{ link.name }}
            {% if link.sublinks %}
                

                    {{ _self.menu_links(link.sublinks) }}
                
            {% endif %}
        
    {% endfor %}
{% endmacro %}

In the main template, do this:

{% import "macros/menu-macros.html" as macros %}

    {{ macros.menu_links(links) }}