Skip to content

Instantly share code, notes, and snippets.

@allejo
Last active September 7, 2017 08:52
Show Gist options
  • Save allejo/a83bcef99a9e0a6f481fce01e492efff to your computer and use it in GitHub Desktop.
Save allejo/a83bcef99a9e0a6f481fce01e492efff to your computer and use it in GitHub Desktop.
Generate a Table of Contents for a Jekyll post with pure Liquid (License: BSD-3)
{% capture tocWorkspace %}
{% comment %}
"...like all things liquid - where there's a will, and ~36 hours to spare, there's usually a/some way" ~jaybe
Usage:
{% include toc_pure_liquid.html html=content sanitize=true class="inline_toc" id="my_toc" h_min=2 h_max=3 %}
Parameters:
* html (string) - the HTML of compiled markdown generated by kramdown in Jekyll
Optional Parameters:
* sanitize (bool) : false - when set to true, the headers will be stripped of any HTML in the TOC
* class (string) : '' - a CSS class assigned to the TOC
* id (string) : '' - an ID to assigned to the TOC
* h_min (int) : 1 - the minimum TOC header level to use; any header lower than this value will be ignored
* h_max (int) : 6 - the maximum TOC header level to use; any header greater than this value will be ignored
Output:
An unordered list representing the table of contents of a markdown block. This snippet will only generate the table of contents and will NOT output the markdown given to it
{% endcomment %}
{% capture my_toc %}{% endcapture %}
{% assign minHeader = include.h_min | default: 1 %}
{% assign maxHeader = include.h_max | default: 6 %}
{% assign nodes = include.html | split: '<h' %}
{% for node in nodes %}
{% if node == "" %}
{% continue %}
{% endif %}
{% assign headerLevel = node | replace: '"', '' | slice: 0, 1 %}
{% assign headerLevel = headerLevel | times: 1 %}
{% assign indentAmount = headerLevel | minus: minHeader | add: 1 %}
{% assign _workspace = node | split: '</h' %}
{% unless headerLevel >= minHeader %}
{% continue %}
{% endunless %}
{% if headerLevel > maxHeader %}
{% continue %}
{% endif %}
{% assign _idWorkspace = _workspace[0] | split: '"' %}
{% assign html_id = _idWorkspace[1] %}
{% capture _hAttrToStrip %}{{ headerLevel }} id="{{ html_id }}">{% endcapture %}
{% assign header = _workspace[0] | replace: _hAttrToStrip, '' %}
{% assign space = '' %}
{% for i in (1..indentAmount) %}
{% assign space = space | prepend: ' ' %}
{% endfor %}
{% capture my_toc %}{{ my_toc }}
{{ space }}- [{% if include.sanitize %}{{ header | strip_html }}{% else %}{{ header }}{% endif %}](#{{ html_id }}){% endcapture %}
{% endfor %}
{% if include.class %}
{% capture my_toc %}{:.{{ include.class }}}
{{ my_toc | lstrip }}{% endcapture %}
{% endif %}
{% if include.id %}
{% capture my_toc %}{: #{{ include.id }}}
{{ my_toc | lstrip }}{% endcapture %}
{% endif %}
{% endcapture %}{% assign tocWorkspace = '' %}
{{ my_toc | markdownify }}
@huhuang03
Copy link

Awesome!!

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment