Django Template: Comparing Dictionary Length in IF Statement

Question

I am trying to compare the length of a dictionary inside a django template

For example, I would like to know the correct syntax to do the following:

 {% if error_messages %}
  <div class="error">
   {% if length(error_messages) > 1 %}
    Please fix the following errors:
    <div class="erroritem">
     {% for key, value in error_messages.items %}
      <br>{{ value }}
     {% endfor %}
    </div>

   {% else %}
     {% for key, value in error_messages.items %}
      {{ value }}
     {% endfor %}
   {% endif %}
  </div>
 {% endif %}

Answer 1

You could do this, using the length filter and the ifequal tag:

{% if error_messages %}
    <div class="error">
        {% ifequal error_messages|length 1 %}
            error_messages[0]
        {% else %}
            Please fix the following errors:
            <div class="erroritem">
            {% for key, value in error_messages.items %}
                <br>{{ value }}
            {% endfor %}
            </div>
        {% endifequal %}
    </div>
{% endif %}

Anything else will have to go down the path of custom tags and filters.

Answer 2

use the smart_if template tag:

http://www.djangosnippets.org/snippets/1350/

its super cool :)

can do all the obvious stuff like:

{% if articles|length >= 5 %}...{% endif %}

{% if "ifnotequal tag" != "beautiful" %}...{% endif %}