Cycle comments on field--comment.html.twig

Question

I would like to add a div for every comment on my field--comment.html.twig

On the template I've a "comments" variable, but if I cycle in this way, I obtain error (Fatal error: "0" is an invalid render array key in /var/www/html/core/lib/Drupal/Core/Render/Element.php on line 97):

{% for comment in comments %}
      {{ comment }}
  {% endfor %}

I would like to add "odd/even" class to comments.

[EDIT] If I use a cycle like this:

{% for key,value in comments %}
  {{ dump(key) }}
{% endfor %}

keys are: #sorted, #pre_render, 'pager', '106', '107' (where 106 and 107 are comment ids)

Answer 1

You can try something like this:

   {% set pre_render = comments['#pre_render'] %}

   {% for key, item in comments if key|first != '#' %}
     {% if key != 'pager' %}
       {% set item = { '#pre_render': pre_render, 0: item } %}
       <div class="comment-{{ cycle(['odd', 'even'], loop.index0) }}">{{ item }}</div>
     {% else %}
       <div class="comment-pager">{{ item }}</div>
     {% endif %}
   {% endfor %}

Answer 2

Loop and set the odd-even classes by using following code:

  {% for comment in comments %}
            {% set classes = cycle(['odd', 'even'], loop.index0) %}
            <div{{ comment.attributes.addClass('comment-', classes ) }} >{{ comment}}</div>
    {% endfor %}