How to check if a block exists in a twig template - Symfony2

Question

Imagine I have something like this in my twig template

{% block posLeft %}    ----- {%endblock%} 

Is there any way to check for existance of the posLeft block without calling to:

block("posLeft")  

And check the return value of the posBlock to varify the existance. I am a newbie in Symfony2 + Twig.

Answer 1

You can solve it like this, if you want to display a certain block only if it has content. Hope, this is what you're looking for.

Example index.html.twig

{% set _block = block('dynamic') %} {% if _block is not empty %}     {{ _block|raw }} {% endif %} 

Example part.html.twig

{% extends "index.html.twig" %}  {% block dynamic %}     Block content goes here. {% endblock %}