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CustomIDs is a preprocessor that allows to define custom identifiers (IDs) for headings in Markdown source by using Pandoc-style syntax in projects built with MkDocs or another backend that provides HTML output. These IDs may be used in hyperlinks that refer to a specific part of a page.


$ pip install foliantcontrib.customids


To enable the preprocessor, add customids to preprocessors section in the project config:

    - customids

The preprocessor supports the following options:

    - customids:
        stylesheet_path: !path customids.css
            - pre
            - mkdocs
            - site
            - ghp
Path to the CSS stylesheet file. This stylesheet should define rules for .custom_id_anchor_container, .custom_id_anchor_container_level_N, .custom_id_anchor, and .custom_id_anchor_level_N classes. Here N is the heading level (1 to 6). Default path is customids.css. If stylesheet file does not exist, default built-in stylesheet will be used.
Allowed targets for the preprocessor. If not specified (by default), the preprocessor applies to all targets.

Custom ID may be specified after a heading content at the same line. Examples of Markdown syntax:

# First Heading {#custom_id_for_first_heading}

A paragraph.

## Second Heading {#custom_id_for_second_heading}

Some another paragraph.

This Markdown source will be finally transformed into the HTML code:

<div class="custom_id_anchor_container custom_id_anchor_container_level_1"><div id="custom_id_for_first_heading" class="custom_id_anchor custom_id_anchor_level_1"></div></div>

<h1>First Heading</h1>

<p>A paragraph.</p>

<div class="custom_id_anchor_container custom_id_anchor_container_level_2"><div id="custom_id_for_second_heading" class="custom_id_anchor custom_id_anchor_level_2"></div></div>

<h2>Second Heading</h2>

<p>Some another paragraph.</p>

(Note that CustomIDs preprocessor does not convert Markdown syntax into HTML; it only inserts HTML tags <div class="custom_id_anchor_container">...</div> into Markdown code.)

Custom IDs must not contain spaces and non-ASCII characters.

Examples of hyperlinks that refer to custom IDs:

[Link to Heading 1](#custom_id_for_first_heading)

[Link to Heading 2 in some document at the current site](/some/page/#custom_id_for_second_heading)

[Link to some heading with custom ID at an external site](
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