I don’t like this book very much. To my taste, the examples and explanations aren’t enough simple, focused and clear as I would like to. The good professor makes a hard theme looks no so hard, and remark only the essentials. In at least one chapter, he uses code that he said “is out of this book scope” and do not explains it, so why he uses it? I don’t finish the reading, it bothers me.
It’s a good introduction to Swift but a bit lacking in depth if you’re already an experienced developer. It would have been nice to see some more complex examples and some topics covered in more detail like annotations, operator overloading/creation, good copy-on-write implementations, and more detailed concurrency information (especially when comparing traditional locking in other languages e.g. in Java and C# this is replaced by that etc.)
Overall, a solid, well written introduction to Swift. About 8 hours of total reading for me, with lots of internet searching between chapters to get a bit more depth in the topics I was most interested in.