The playground covers two of the most important topics in the standard library:
- Strings (because strings are different in Swift)
- Sequences and collections (including a very helpful implementation of a custom collection type)
It’s a great addition to Apple’s Swift book because you can play around with the code and the explanations in the playground are more extensive than in the book. It “only” covers the standard library, however, so language features like the new
try/catch error handling syntax are not included.
The playground requires Xcode 7. To see the page structure, make sure to show the Project Navigator. And if you’re seeing the raw documentation comments, choose
Editor > Show Rendered Markup to switch to the formatted view.