Filter a list of resource ids on category, or test if a single resource id belongs to a category.

This filter can be applied to a list of resource ids or a single resource id.

When it is applied to a list then it will filter the list of ids. Only those resource ids that belong to a certain category remain. Optionally the filter only returns the first n matches.

When applied to a single integer (resource id), then it will return a boolean. True when the id belongs to the parameter’s category, false otherwise.

Apply to a single resource id


{{ 1|is_a:"person"|yesno }}

Will output “yes”, because the resource with id 1 is a person (the System Administrator).

Apply to a list of resource ids

When applied to a list of ids:

{% for part_id in m.rsc[id].o.haspart|is_a:"person" %}
    {{ m.rsc[part_id].title }}
{% endfor %}

This will list all collection members that are a person. While:

{% for part_id in m.rsc[id].o.haspart|is_a:"person":3 %}
    {{ m.rsc[part_id].title }}
{% endfor %}

Lists only the first three collection members that are a person.

Edit on GitHub

is_visible Resource lists is_not_a

Referred by


Filters transform template variables before they are rendered.


is_not_a mirrors is_a. It is particularly useful when iterating over a category and excluding members of a sub-category…