I don't like the idea to make the build process more complex at all. But if you have the tools to generate an XML out of your markdown format, that solves the problem for you, doesn't it?

I actually find the XML format easier to use because it's relatively simple. Using markdown, I never know what exactly is supported, which characters have special meanings, etc. I never really got the hang of writing in wikis.

The "related functions" section is annoying. It's almost impossible to maintain. The only time is useful is when you add links to other parts of the documentation, e.g. linking the object category documentation from GetCategory(). Otherwise, smart sorting into categories is the better solution. I don't know if multiple tags are even needed.

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