I’ve long been a fan of pbook, converts a buffer containing source code into a
marked-up LaTeX document. But the implementation was a bit crufty and not
easy to customize, so I never used it as much as I would have liked. Recently
I stumbled upon [http://lukego.github.io/blog/2012/10/24/readable-programs/],
where Luke replaces the whole program with a sed one-liner. rs-pbook is an
implementation of his approach, surrounding the global search-and-replace with
a bit of Emacs comfort (auto-handling comment prefixes, making the output
format extensible, creating a buffer with a proper filename, etc.).
Write your source code as usual, sprinkling it with top-level comments beginning in column 0. These comments will be converted to text, everything else becomes code blocks.
M-x rs-pbook creates a buffer in org or markdown format. Use this to create
pdf or html, browse on screen, or print it out and read on the bus. Hope it
is useful!