I'm interested in compiling a list of major programming languages and their preferred documentation toolsets. To scope this a bit:

• The exact structure of the answer may vary from language to language, but there appear to be two aspects common to all languages: (1) in-code syntax for documentation, and (2) documentation generators that make use of said syntax.

• There are also cases where generators are used independent of code. For example, tutorial-style documentation is common in the Python world and is often disconnected from underlying code.

• Many languages have multiple commonly-used documentation strategies and tool chains, and I'd love to capture this.

• Finally, there are cross-language tools like Doxygen that also have some traction and would be worth noting here.

Here are some obvious target languages to start with: Python, Ruby, Java, C#, PHP, Objective-C, C/C++, Haskell, Erlang, Scala, Clojure

If this question catches on, I'll try and keep this section updated with the most recent list.

Thanks!