title: Twig extension: custom tag with un-rendered body
body: <p>Is it possible to create a custom tag with an un-rendered body? E.g.</p>
  
  <pre><code>{% mytag 'home' %}Welcome at {{ homepage }}{% endmytag %}
  </code></pre>
  
  <p>I would like to have the value of the <code>{{ homepage }}</code> variable in the new mytag function.</p>