serum v1.4.1 Serum.Plugins.TableOfContents View Source

A Serum plugin that inserts a table of contents.

Using the Plugin

First, add this plugin to your serum.exs:

%{
  plugins: [
    Serum.Plugins.TableOfContents
  ]
}

This plugin works with both pages(.md, .html, and .html.eex) and blog posts(.md). Insert the <serum-toc> tag at the position you want to display a table of contents at.

<serum-toc start="2" end="4"></serum-toc>

The start and end attributes define a range of heading level this plugin recognizes. In the case of the above example, <h1>, <h5>, and <h6> tags are ignored when generating a table of contents.

After this plugin has run, each <serum-toc> tag is replaced with an unordered list:

<ul id="toc" class="serum-toc">
  <li class="indent-0">
    <a href="#s_1">
      <span class="number">1</span>
      Section 1
    </a>
  </li>
  <!-- More list items here... -->
</ul>

This plugin produces a "flat" unordered list. However, each list item tag has an indent-x class, where x is an indentation level (from 0 to 5) of the current item in the list. You can utilize this when working on stylesheets.

The id attribute of each target heading tag is used when hyperlinks are generated. If the element does not have an id, the plugin will set one appropriately.

Notes

You may use <serum-toc> tag more than once in a single page. However, all occurrences of this tag will be replaced with a table of contents generated using the attributes of the first one. That is, for example, all three tags in the code below expand to the same table of contents, showing a 2-level deep list.

<serum-toc start="2" end="3"></serum-toc>
...
<serum-toc></serum-toc>
...
<serum-toc></serum-toc>

It's recommended that you wrap a <serum-toc> tag with a <div> tag when using in a markdown file, to ensure a well-formed structure of HTML output.

<div><serum-toc ...></serum-toc></div>

And finally, make sure you close every <serum-toc> tag properly with </serum-toc>.

Link to this section Summary

Functions

Returns the short description of the plugin.

Returns the version requirement of Elixir.

Returns a list of optional callbacks which the plugin implements.

Returns the name of the plugin.

Returns the version requirement of Serum.

Returns the version of the plugin.

Link to this section Functions

Returns the short description of the plugin.

You must implement this callback, or the plugin may fail.

Callback implementation for Serum.Plugin.description/0.

Returns the version requirement of Elixir.

Refer to this document for the string format.

You must implement this callback, or the plugin may fail.

Callback implementation for Serum.Plugin.elixir/0.

Returns a list of optional callbacks which the plugin implements.

Each list item can be in one of two forms:

  • {callback_name, arity}
  • callback_name - This is deprecated and left for compatibility. New Serum plugins must use the above format.

For example, if your plugin implements build_started/2 and finalizing/2, you must implement this callback so that it returns [build_started: 2, finalizing: 2].

You must implement this callback, or the plugin may fail.

Callback implementation for Serum.Plugin.implements/0.

Returns the name of the plugin.

You must implement this callback, or the plugin may fail.

Callback implementation for Serum.Plugin.name/0.

Link to this function

rendering_fragment(html, metadata, arg3)

View Source

Callback implementation for Serum.Plugin.rendering_fragment/3.

Returns the version requirement of Serum.

Refer to this document for the string format.

You must implement this callback, or the plugin may fail.

Callback implementation for Serum.Plugin.serum/0.

Returns the version of the plugin.

The returned version string must follow the semantic versioning scheme.

You must implement this callback, or the plugin may fail.

Callback implementation for Serum.Plugin.version/0.