Swift 5.1 Released!

Swift 5.1 builds on the strengths of Swift 5 by extending the stable features of the language to compile time with the introduction of module stability. With module stability it’s now possible to create and share binary frameworks that will work with future releases of Swift. Swift 5.1 also extends the capabilities of the language and the standard library with new features such as property wrappers, opaque result types, key path member lookup, diffing for appropriate collection types, and new APIs for String. Altogether the new features of Swift 5.1 make it easier to design better APIs and reduce the amount of common boilerplate code.

→ swift.org/blog/swift-5.1-released/

Swift 5.1 advances Swift 5 by introducing module stability, enabling binary frameworks that work across compiler versions, alongside library evolution support for resilient APIs.

The standard library gains features like collection diffing, enhanced array initialisation, new String APIs for contiguous handling and Unicode, SIMD vector improvements, and the Identifiable protocol. Language enhancements include property wrappers for custom access patterns, opaque result types for flexible returns, key path member lookup, expanded Self usage, synthesised property defaults, and implicit returns in single-expression functions.

SwiftSyntax sees performance boosts through parser integration, and the toolchain includes SourceKit-LSP for Language Server Protocol support, with source compatibility to Swift 5 and migration tools in Xcode 11.