The documentation has been written in Org mode for GNU Emacs, with
both Texinfo and reStructuredText formats generated from that. The
Texinfo files are intended for use with the rest of the GnuPG
documentation; while the reStructuredText files are intended for use
with Docutils and Sphinx, as with other Python projects.
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* Cautionary Notes regarding Sphinx and EPUB::
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@node Cautionary Notes regarding Sphinx and EPUB
@subsection Cautionary Notes regarding Sphinx and EPUB
Though Python's Docutils in conjunction with Sphinx is capable of
generating some very useful HTML sites, as proven by @uref{https://readthedocs.org/, Read the Docs} and
the @uref{https://docs.python.org/, Python documentation}, there are a number of output formats it does
not handle well. At the top of the list of things it manages to break
so atrociously as to be embarassing is the @uref{http://idpf.org/epub, EPUB 3} format.
The automatically generated EPUB of the CPython documentation always
contains hundreds of validation errors and even the modest amount of
documentation here @uref{https://files.au.adversary.org.s3.amazonaws.com/crypto/gpgme-python/rst/epub/GPGMEPythonBindings.epub, produced a file} with approximately thirty
validation errors. As the volume of documentation content increases,
so does the induced errors. Whereas Texinfo doesn't produce EPUB
output at all, nor does Org-mode.
Should there ever be genuine demand for this format, lodge a @uref{https://dev.gnupg.org/maniphest/task/edit/form/4/, feature
request} case marked for @uref{https://dev.gnupg.org/p/BenM/, my} attention. The means of generating such
files flawlessly is already available, but is not yet part of the
GnuPG build system. Nor is it integrated with a means of converting
Org mode input files to the relevant base format automatically, as can
already be done when converting Org to reStructuredText or Org to
Texinfo. As a certain amount of work would be required to get it
done, there would need to be clear demand for that work to be done.