toc
Filter to derive a Table Of Contents from a HTML body.
This filter extracts a nested table of contents from the h2..h6 elements in a HTML text.
The headers may not have any attributes (ie. only <h2>).
All sections are wrapped in <div> elements, this to make it possible to make the
headers sticky without having them overlap.
Example usage:
{% with id.body|toc as toc, body %}
{% include "page-parts/_toc.tpl" toc=toc %}
{{ body|show_media }}
{% endwith %}
The returned ToC tree is a nested tree of 3-tuples:
[ {<<"toc1">>, <<"Text of header">>, [ ... ]}, ... ]
The third element is a list of sub-headers.
To generate a nested table of contents from the above structure:
{% include "page-parts/_toc.tpl" toc=toc %}
And then the page-parts/_toc.tpl as:
{% with level|default:1 as level %}
{% if toc %}
<ol class="toc-level-{{ level }}">
{% for p, text, sub in toc %}
<li>
<a href="#{{ p }}">{{ text }}</a>
{% include "page-parts/_toc.tpl" toc=sub level=level+1 %}
</li>
{% endfor %}
</ol>
{% endif %}
{% endwith %}