===================
Templates
===================

Relative imports and extends in templates
-------------------------------------------

Django templates can not import via relative imports. This is therefore wrong.::

    {% extends '../base.html' %}
    
    {% include '../../breadcrumbs_frag.html' %}


Solution:
Always import as specified from the application/template directory, or the
`TEMPLATE_DIRS` specified in `settings.py`


Not wrapping {% for %} in {% if %}
--------------------------------------------

A common pattern is::

    <ul><!-- or any other element, eg table -->
    {% for comments in post.comment_set.all %}
    <li>
    {{ comment }}
    </li>
    {% endfor %}
    </ul>

This doesnot handle an empty queryset, and will create a empty `<ul></ul>`,
which might be visible and break your design depending on your css.


Solution:

Wrap it in `{% if %}`::
    
    {% if post.comment_set.all %}
    <ul><!-- or any other element, eg table -->
    {% for comments in post.comment_set.all %}
    <li>
    {{ comment }}
    </li>
    {% endfor %}
    </ul>
    {# optional else #}
    {% else %}
    <div>No comment</div>
    {% endif %}
    
Or (Django 1.1 only)

    <ul><!-- or any other element, eg table -->
    {% for comments in post.comment_set.all %}
    <li>
    {{ comment }}
    </li>
    {% empty %}
    <li>
    No comment
    </li>
    {% endfor %}
    </ul>

Template Silencing:
--------------------

Any empty variable is rendered empty in the templates. But errors are rendered empty as well.
Django templates silence many variable errors and render nothing at that position.

Solution:

During development set the template string to a convenient value when the template string is invalid.

This setting helps.::

TEMPLATE_STRING_IF_INVALID = '{{ %s }}'

Tip: This should be one of the settings in your `localsettings`, or one of conditions within `if DEBUG:`

Warning: The breaks the admin design.