Iterating over all docstrings in a Lisp buffer

[Sebastian Wiesner]

Hello,

how would I iterate over all function/macro/variable docstrings in an Emacs 
Lisp buffer?

The idea is to write a command that automatically re-wraps all docstrings in 
the current buffer.  I’d like to use this as part of a test suite to 
automatically check whether contributed code adheres to the Emacs Lisp style 
guide.

Thanks,
Sebastian Wiesner