How can I check the size of a collection within a Django template?

Question

I have a list in my Django template. I want to do something only if the size of the list is greater than zero.

I have tried myList|length and m

Answer 1

If you're using a recent Django, changelist 9530 introduced an {% empty %} block, allowing you to write

{% for athlete in athlete_list %}
  ...
{% empty %}
  No athletes
{% endfor %}

Useful when the something that you want to do involves special treatment for lists that might be empty.