nunjucks set create object

Question

As nunjucks now supports using set as a block I wanted to do something like this:

{% set navigationItems %}
  {% for item in items %}
    { name: item.name, url: item.url }{% if not loop.last %},{% endif %}
  {% endif %}
{% endset %}

Then call this variable as the input object on another macro, like so:

{{ navigation(items=[navigationItems]) }}

However, navigationItems is evaluated as a string, not an array-literal. Any idea how, or if this is possible?

Thanks.

Answer 1

I'm not exactly sure what you're trying to accomplish. It looks like you want to loop over one array called items and copy it into a new array called navigationItems . Perhaps items contains more keys than you want to pass to the macro?

I'm going to make that assumption, otherwise you could simply copy items into navigationItems like so:

{% set navigationItems = items %}

This example works:

{% macro navigation(items) %}
    <ul>
        {% for item in items %}
            <li>{{ item.name }} - {{ item.url }}</li>
        {% endfor %}
    </ul>
{% endmacro %}

{% set websites = [
    {
        name: 'Google',
        url: 'http://google.com',
        description: 'A search engine'
    },
    {
        name: 'GitHub',
        url: 'http://github.com',
        description: 'A webapp for your git repos'
    },
    {
        name: 'StackOverflow',
        url: 'http://stackoverflow.com',
        description: 'The answer: 42'
    }] %}

{% set navigationItems = [] %}
{% for website in websites %}
    {% set navigationItems = (navigationItems.push({name: website.name, url: website.url}), navigationItems) %}
{% endfor %}

{{ navigation(items=navigationItems) }}

websites values contain a description key which is not passed on to the navigationItems array. If it were me, I'd just pass website directly to the navigation macro since your keys: name and url are the same in both arrays.

The pattern here is almost like a map method in Javascript or Ruby.