Whats new in Swift

Community update

• DocC and swift website open sourced
• New c++ interop workgroup to explore integration

Swift packages

• TOFU, trust on first use, package fingerprinting
• Command plugins, ie formatters and linters
  • DocC gets objc and c support
  • Build tool plugins too, can add additional steps during build

Performance improvements

• Build times faster
  • Swift directly in xcode build tools instead of a separate executable
• Faster type checking, with new implementations
• Runtime improvements
  • Protocol api cacheing

Concurrency updates

• Can back deploy async await to older OSs
• Data race avoidance
  • Moving to thread safety by default for swift 6
  • actor and distributed actor. See additional session about this
• Async algorithms
  • Open source package for things using AsyncSequence
  • zip, merge, debounce, chunked
• Actor prioritization, priority-inversion avoidance
  • New swift actor instrument, to visualize swift tasks

Expressive swift

• if let thing = thing becomes if let thing. works for guard as well
• .compactMap, map but filtering nil
• New rules for pointer conversions when calling c functions
• String processing
  • Less trimming/splitting etc, more regex
  • Literals are declared between forward slashes
  • Or, can create regexes with a swiftUI style syntax library.
    • Can turn these in to nestable components, or recursive
    • Take care of types and matching, ie for dates
  • Uses a new regex parser in swift
• Generic code clarity
  • Fixes for tricky errors I’ve never ran into
  • Adds the any keyword to distinguish box types of protocol conformance from generic types
  • But generics are better, so use them when possible
    • new some keyword allows removing some boilerplate with generics