Awesome

What’s new in Swift 4

An Xcode playground showcasing the new features in Swift 4.0. As seen in the What’s New in Swift session at WWDC 2017.

Written by Ole Begemann, May–September 2017.

See also: my What’s new in Swift 4.2 playground from 2018.

The playground requires Swift 4. Xcode 9 includes Swift 4 by default.

You can also run it in Xcode 8.3, but you need to install the latest Swift 4.0 snapshot from swift.org (don’t worry, it’s easy).