filter
Filters a list on the value of a property, either on presence or equality.
Testing presence
To filter a list of values:
{% print somelist|filter:`p` %}
Results in a list where all elements have the property p defined and
where the property (after conversion to boolean) is true.
This can be used to filter a list of resource ids on the presence of a property. For example, to see all published elements in a list of resource ids:
{% print [1,2,3,4,5,6]|filter:`is_published` %}
To find all pages from page connection hasdocument that have an image:
{% print id.o.hasdocument|filter:`depiction` %}
Testing equality
A second argument can be added to test on equality:
{% print somelist|filter:`title`:"Untitled" %}
Shows all elements whose title property is “Untitled”.