[doc] Fix the example for length
@@ -7,7 +7,7 @@ The `if` tag allows you to designate a chunk of content as conditional depending
{% verbatim %}
{% if users is empty %}
There are no users.
-{% elseif users.length == 1 %}
+{% elseif users|length == 1 %}
There is only one user.
{% else %}
There are many users.
