map

Creates an array of values by extracting the values of a named property from another object.

In this example, assume the object site.pages contains all the metadata for a website. Using assign with the map filter creates a variable that contains only the values of the category properties of everything in the site.pages object.

Input

{% assign all_categories = site.pages | map: "category" %}

{% for item in all_categories %}
{{ item }}
{% endfor %}

Output

business
celebrities
lifestyle
sports
technology