The internal MoinPage DOM

At the core of Moin’s document conversion is an “EmeraldTree” based internal document format, the MoinPage DOM tree.

Unfortunately, the MoinPage format is only sparsely documented, with hints in ../../src/moin/utils/tree.py and docstrings and comments in the converter modules in ../../src/moin/converters/. Also the unit tests in ../../src/moin/converters/ reveal some insights.

This document is an attempt to improve the situation. Please help by revising and adding information and insights.

Elements

As the main target format is HTML, the most complete and up to date authority on MoinPage elements and their attributes is the source of the HTML-Out converter ../../src/moin/converters/html_out.py.

Most MoinPage elements are equivalent to HTML elements.

Some share also the name:

<a>, <aside>, <audio>, <blockquote>, <code>, <del>, <div>, <figure>, <figcaption>, <ins>, <kbd>, <object>, <p>, <s>, <samp>, <span>, <strong>, <sub>, <sup>, <table>, <u>, <video>

Others have a more descriptive name (mostly inspired by DocBook):

<blockcode>, <block_comment>, <emphasis>, <line_break>, <quote>, <separator>, <table_body>, <table_cell>, <table_cell_head>, <table_footer>, <table_header>, <table_row>

Additional elements represent features present in several input formats but missing in HTML (mainly inspired by DocBook or Docutils)

<admonition>, <note>, <noteref>, <nowiki>, <line_block_line>, <line_block>, <literal>, <page>, <table_of_content>

At some stages, the representation in MoinPage differs from HTML:

  • A single heading element <h level=N> replaces HTML’s <h1>, …, <h6>.

  • The various list types are represented by <list> <list_item>, <list_item_label>, <list_item_body> using a set of specific attributes.

The “macro” feature uses the special auxiliary elements <part> and <inline_part>.

Namespaces

Almost all elements and many of their attributes use the moin-page namespace.

However, elements and attributes may use “foreign” namespaces to “inherit” definitions from external specifications or to prevent naming collisions. Converters may use “foreign” namespaces on moin DOM elements to attach additional information for round-trips or for the HTML rendering.

  • xinclude is used for transclusions (<include> element and some of its attributes).

  • xlink is used for link-related attributes (similar to DocBook).

  • xml is used for the “id”, “lang”, and “base” attributes (similar to DocBook) by docbook_in, html_in, and markdown_in while mediawiki_in, moinwiki_in and rst_in use “moinpage:id”. html_out supports both, “xml:id” and “moinpage:id”.

    TODO: consistently use “xml:id”?

  • html is used for the “data-lines” attribute added by Moin to moin DOM elements. html is also used by various …-in converters for attributes defined in the HTML standard (“alt”, “class”, “style”, “href”, …).

Representation of inline text that is some literal value

In addition to a generic “literal text” markup, MoinPage supports three, more specific “monospace-styled” elements:

MoinPage

<literal>

<code>

<kbd>

<samp>

DocBook

<literal>

<code>

<userinput>

<computeroutput>

HTML

<tt> [1]

<code>

<kbd>

<samp>

MediaWiki

<tt> [1]

<code>

<kbd>

<samp>

Markdown

<tt> [1]

`…`

<kbd>

<samp>

MoinWiki

`…`

{{{…}}}

n/a

n/a

rST

``…``

:code:`…`

:kbd:`…`

:samp:`…`

Creole

{{{ … }}}

n/a

n/a

n/a