ole / whats-new-in-swift-4

An Xcode playground showcasing the new features in Swift 4.0.

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).

whats-new-in-swift-4's Issues

Swift 4 and Foundation - New block-based KVO

Hi,
With the WWDC 2017 in session 201 What's New in Cocoa Touch (21m01) Apple introduce a new block-base KVO.
Is not a pure Swift 4 feature 🤔 but it's may be interesting to mention on your playground 😉

integer-protocols.png is not displaying

integer-protocols.png, referenced by the "New Integer Protocols" page is not displaying. I spent a few minutes trying tweaking the resource in the page but nothing causes it to display. I see it in the Resources folder. Is this just an Xcode 9 bug?

Associated type constraints page broken by Xcode 9b3

I haven't had time to dig into exactly what's wrong but the associated type constraints page no longer compiles with Xcode 9 beta 3.