More-or-less readable Markdown can be generated. A doclet needs to be written that also creates a markdown-based index and overview. Currently, the edoc_doclet creates an index.html and overview.html, which do not point to the .md files.
To generate markdown edoc, run:
edoc:application(App, [{doclet, edown_doclet} | OtherOpts]).
The edown_xmerl module is used as an xmerl export module.
It converts xmerl's "simple xml" to Markdown syntax. Note that
GH-flavored Markdown allows HTML markup (at least common tags),
but doesn't expand markdown markup inside HTML markup, so the
edown_xmerl module has to know the context in which it operates.
EDoc provides a plugin structure, so that one may specify own layout modules, export modules, and doclets. However, there is some overlap esp. between the layout and doclet modules, and several functions are expected to produce files on their own. This causes a problem for EDown, since it cannot handle frames. Instead, it would probably like to create one overview file with different sections. It would have been better to have a framework where some plugin functions identify the different files to be written, and the outline of each, other plugins convert to suitable content representation (e.g. HTML or Markdown), and EDoc then writes the files necessary.
For now, EDown focuses on producing reasonable Markdown, rather than complying fully with the plugin framework. That is, the edown_doclet module will not go out of its way to function together with any other layout module than edown_layout, and vice versa.