Swift 4.2 is a major language release and comprises of language changes such as Generics improvements, and Standard library updates.
Better support has been added for Generics which ultimately makes more of your code reusable.
The standard library in this latest release consists of a number of new features such as improvements to the Hashable protocol and a new unified set of randomization functions and protocols.
Swift 4.2 has enabled the binary compatibility for future releases of Swift. Support has been added for batch mode compilation that results in faster build times. There’s a change in calling convention for retain/release cycle which helps reduce the code size and improve runtime performance.
Swift 4.2 explores three new features namely, batch mode support, improved scheme generation logic, and automatic Xcode project generation.
With Swift 4.2, the swift targets will be now compiled using the Swift compiler’s batch mode The scheme generation logic has been improved and it generates the following schemes:
Swift 4.2 offers automatic Xcode project generation. The generate-xcodeproj here has a new –watch option which enables it to watch the file system and regenerate the Xcode project automatically, if needed.
For more information on this release, check out the official release notes.
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