How can I wrap a block in jinja2

Question

I basically want to do something like this in my base template:

{% if the block 'headline' is not empty %}
<div class="something"><h1>{% block headline %}{% end block %}</h1></div>
{% endif %}

In jinja2 it appears blocks are not variables and you can't get at their contents or test their values, or anything else but output them.

This seems like it would be a no-brainer to allow this, but I can't figure out a way. Do I have to use macros instead of blocks?

Answer 1

You should be able check the contents of a block using the self.blockname syntax.

{% if self.headline() is not empty %}
{# Write out Headline HTML wrapper here #}
{% endif %}

To quote from the documentation :

If you want to print a block multiple times you can however use the special self variable and call the block with that name:

<title>{% block title %}{% endblock %}</title>
<h1>{{ self.title() }}</h1>
{% block body %}{% endblock %}