PageTocFilter

Inserts a table of contents on a page via the HTML::Pipeline.

Add this line to your application's Gemfile:

gem 'page-toc-filter'

And then execute:

$ bundle

Or install it yourself as:

$ gem install page-toc-filter

The simplest way to do this is

require 'page-toc-filter'

Then, place this filter after you've rendered your content through the Markdown and TOC filters:

pipeline = HTML::Pipeline.new([
  HTML::Pipeline::MarkdownFilter,
  HTML::Pipeline::TableOfContentsFilter,
  HTML::Pipeline::PageTocFilter
])

Then, on your page, enter the text {:toc} to have it replaced by a table of contents.

By default, only h2 headings will be converted into a table of contents. You can change this with the optional toc_levels setting, which should be a comma-separated string of heading levels. For example:

pipeline = HTML::Pipeline.new([
  HTML::Pipeline::MarkdownFilter,
  HTML::Pipeline::TableOfContentsFilter,
  HTML::Pipeline::PageTocFilter
], { :toc_levels => 'h2, h3' })