Swift 4.2 Released!

Swift 4.2 is now officially released! Swift 4.2 builds on the strengths of Swift 4, delivering faster compile times, improving the debugging experience, updating the standard library, and converging on binary compatibility.

→ swift.org/blog/swift-4.2-released/

Swift 4.2 is a major update that enhances compile times, debugging, the standard library, and moves closer to binary compatibility, while maintaining source compatibility with Swift 4 and 4.1 but marking the last release to support Swift 3 compatibility.

It advances generics with conditional conformance, introduces standard library features like improved hashing and randomisation, and implements various Swift Evolution proposals such as dynamic member lookup and derived enum collections.

The Swift Package Manager gains batch mode compilation, automatic Xcode project generation with file watching, and new APIs for local dependencies and system libraries.