The comments in header files are often the only (or only useful) documentation. So don’t give up before looking there. Sometimes they wait a few years to write

The comments in header files are often the only (or only useful) documentation. So don’t give up before looking there. Sometimes they wait a few years to write docs. For example, NSWindowAccessoryViewController went undocumented for three or four years. Which was fine because it was too buggy for me to use anyway. The docs are enough to get you started but it’s only brutal experience that teaches you how to use things. In practice you spend a lot of time working around bugs and design flaws. Those will never be documented, of course.