docs/_includes/sidebar.html

{% if page.toc %}
  {% assign p = page.toc %}
{% else %}
  {% assign p = 'toc.json' %}
{% endif %}
{% capture toc_string %}{% readj p %}{% endcapture %}
{% jsonball toc from var toc_string %}

{% capture pagesiteurl %}{{ site.url }}{{ page.url }}{% endcapture %}

<div id="sidebar_toc">
{% for x in toc %}
    {% capture ifactive %}{% if pagesiteurl == x.file %}toc-active
      {% else %}{% if x.children %}{% for x2 in x.children %}
        {% if pagesiteurl == x2.file %}toc-active{% else %}{% if x2.children %}{% for x3 in x2.children %}
            {% if pagesiteurl == x3.file %}toc-active{% endif %}
          {% endfor %}{% endif %}
        {% endif %}
      {% endfor %}{% endif %}
    {% endif %}{% endcapture %}
    {% capture ifactive %}{{ ifactive | trim }}{% endcapture %}
    
	  <div class="toc-1 {{ ifactive }}">
  {% if x.children %}
	    <a href="{{ x.file }}"><div class="toc-1-item toc-1-header {% if pagesiteurl == x.file %}{% if x.exclude %}{% else %} toc-active{% endif %}{% endif %}">{{ x.title }}</div></a>
        <div class="toc-1-children">
    {% for x2 in x.children %}
        {% capture ifactive %}{% if pagesiteurl == x2.file %}toc-active{% else %}{% if x2.children %}{% for x3 in x2.children %}
            {% if pagesiteurl == x3.file %}toc-active{% endif %}
          {% endfor %}{% endif %}
        {% endif %}{% endcapture %}
        {% capture ifactive %}{{ ifactive | trim }}{% endcapture %}
	      <div class="toc-2 {{ ifactive }}">
      {% if x2.children %}
	        <a href="{{ x2.file }}"><div class="toc-2-item toc-2-header{% if pagesiteurl == x2.file %}{% if x2.exclude %}{% else %} toc-active{% endif %}{% endif %}">{{ x2.title }}</div></a>
            <div class="toc-2-children-popup"><div class="toc-2-children">
        {% for x3 in x2.children %}
            {% capture ifactive %}{% if pagesiteurl == x3.file %}toc-active{% endif %}{% endcapture %}
              <div class="toc-3 {{ ifactive }}">
	            <a href="{{ x3.file }}"><div class="toc-3-item{% if pagesiteurl == x3.file %}{% if x3.exclude %}{% else %} toc-active{% endif %}{% endif %}">{{ x3.title }}</div></a>
              </div>
        {% endfor %}
            </div></div>
      {% else %}
	        <a href="{{ x2.file }}"><div class="toc-2-item{% if pagesiteurl == x2.file %} toc-active{% endif %}">{{ x2.title }}</div></a>
      {% endif %}
          </div>
    {% endfor %}
        </div>
  {% else %}
	    <a href="{{ x.file }}"><div class="toc-1-item{% if pagesiteurl == x.file %} toc-active{% endif %}">{{ x.title }}</div></a>
  {% endif %}
      </div>
{% endfor %} 
</div>
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