Recently a post by jao, who’s written a whole bunch of excellent software, popped up in my feed inbox. It’s just a very short (15 words) mention of apropos-library, a function that lists all the variables and functions in a library. It can also be configured to show the keybindings for the functions.
Apparently it’s been around since Emacs 23 but neither jao nor I were aware of it. It seems like a useful facility. Even though you won’t need it often, it’s easy to see how it could be really useful in certain circumstances. It’s already installed so give it a try to see how it works.