A lot of Apple documentation is just a list of functions a class has without any explanation whatsoever. Many sample projects are written in older swift versions and don't compile anymore. Xcode 11 can only convert swift 4 to swift 5. A lot of samples are still swift 2 or 3. So you either have to manually fix the errors or install an older xcode version to convert them. Such a waste of time.

And you know it's bad when Microsoft has better Apple docs than Apple has: https://twitter.com/akashivskyy/status/1187790245804367873