Instead of generating a file for code and one for documentation, do both
via a macro instead. Most of the code is the same (modulo reformatting
in a more modern style), and instead of printing the result to a file,
it just returns it as the result of a macro. (Since this is done in a
naive way, the macro is bad -- it is unhygienic since this is basically
what it did before only through a generated file; it should eventually
be improved to avoid these hacks.)
