panel/app/views/posts/attributes/_array.haml

.form-group{ class: invalid(post, attribute) }
  = label_tag "post_#{attribute}", post_label_t(attribute, post: post)

  .taggable{ data: { values: metadata.value.join(','),
    name: "post[#{attribute}][]", list: id_for_datalist(attribute),
    remove: 'false', legend: post_label_t(attribute, post: post),
    described: id_for_help(attribute) } }

    = text_field(*field_name_for('post', attribute, '[]'),
      value: metadata.value.join(', '),
      **field_options(attribute, metadata))

  = render 'posts/attribute_feedback',
    post: post, attribute: attribute, metadata: metadata

  %datalist{ id: id_for_datalist(attribute) }
    - site.everything_of(attribute).each do |value|
      %option{ value: value }