A count in a loop

Question

Hello i would like do somthing like that:

<?php $count = 0; foreach($a as $v): $count++; ?>   <?php if ($count%2 == 0): ?>     ...   <?php endif; ?> <?php endforeach; ?> 

in twig:

{% for v in a %}    {% if ??? is even %}     ...   {% endif %} {% endfor %} 

but how can i have a variable evolving with loop ?

Answer 1

Apparently twig defines some loop variables inside the for-loop:

{% for v in a %}     {% if loop.index0 is even %}         ...     {% endif %} {% endfor %}