{%-comment-%}

via https://riaanhanekom.com/2018/03/01/setting-up-jekyll-related-posts-and-series
NOTE: liquid append-remove trick (`-@$remove@me`) inspired by https://vsoch.github.io/2019/jekyll-lists/

{%-endcomment-%}

{%-if page.series-%}

{%-case page.type-%}
  {%-when 'posts'-%}    {%-assign series_collection = site.posts-%}
  {%-when 'projects'-%} {%-assign series_collection = site.projects-%}
  {%-when 'pages'-%}    {%-assign series_collection = site.pages-%}
  {%-when 'people'-%}   {%-assign series_collection = site.people-%}
{%-endcase-%}
{%-assign series = series_collection | where: "series", page.series |  where: "published", true | sort: 'date' %}

<!– Series Aside –>

<aside class="series">
  <header>
    <h3>{{ page.series | replace: '-',' ' | capitalize }} <span class="header-aside"> - {% if page.type=='people'-%}group{%-else-%}{{ include.series_type | default: page.type | append: "-@$remove@me" | remove: "s-@$remove@me" }} series</span>{%-endif-%}</h3>
  </header>
  <ol class="series">
  {%-for item in series %}
    <li{%-if item.url == page.url %} class="active"{%-endif-%}>
    {%-if item.url == page.url-%}
      {{-item.title-}}
    {%-else-%}
      <a href="{{-item.url-}}">{{-item.title-}}</a>
    {%-endif-%}
    </li>
  {%-endfor %}
  </ol>
</aside>

{%-endif %}