DocBook
From APIDesign
DocBook is a language that rebuilds TeX on top of XML. In its use it resembles HTML, however it sort of deals with higher level abstractions (section, citation, reference, etc.), so it more suitable for additional processing (to PDF, etc.).
Btw. TheAPIBook has been written in Docbook. However Apress required the text to be in Microsoft Word format, so I had to do an automatic conversion. As such at the time of publishing TheAPIBook I was expert on OpenDocument format and various XSL tricks. In case anyone needs Docbook to OpenDocument conversion script, contact me, I can expose what I had to global world.
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