Liquid templates - accessing members by name

Question

I'm using Jekyll to create a new blog. It uses Liquid underneath.

Jekyll defines certain "variables": site, content, page, post and paginator. These "variables" have several "members". For instance, post.date will return the date of a post, while post.url will return its url.

My question is: can I access a variable's member using another variable as the member name?

See the following example:

{% if my_condition %}
  {% assign name = 'date' %}
{% else %}
  {% assign name = 'url' %}
{% endif %}

I have a variable called name which is either 'date' or 'url'.

How can I make the liquid equivalent of post[name] in ruby?

The only way I've found is using a for loop to iterate over all the pairs (key-value) of post. Beware! It is quite horrible:

{% for property in post %}
  {% if property[0] == name %}
    {{ property[1] }}
  {% endif %}
{% endfor %}

Argh! I hope there is a better way.

Thanks.

Answer 1

I don't know what I was thinking.

post[name] is a perfectly valid liquid construction. So the for-if code above can be replaced by this:

{{ post[name] }}

I thought that I tried this, but apparently I didn't. D'oh!

Liquid admits even fancier constructs; the following one is syntactically correct, and will return the expected value if post, element, categories, etc are correctly defined:

{{ post[element.id].categories[1].name }}

I am greatly surprised with Liquid. Will definitively continue investigating.

Answer 2

Actually, this did not work for me. I tried a bunch of different combinations and what finally worked was

<!-- object myObj.test has the string value "this is a test" -->
{% assign x = 'test' %}
{{ myObj.[x] }}

Output: this is a test