1.0.0 - First Full Release of Dispatch Async

🚀 First 1.0.0 Semver-stable release 1.0.0 of swift-dispatch-async - a pure-swift implementation of libDispatch

swift-dispatch-async is a lightweight Swift package providing core Grand Central Dispatch (GCD)–APIs implemented using Swift Concurrency. Pure Swift, no direct C or Posix library usage.

Designed to provide support for Swift for WebAssembly / WASI, where the standard Dispatch library has been previously unavailable.

🎯 Overview

• Implements a minimal compatibility layer for Dispatch APIs using async/await.
• Enables Swift for WebAssembly builds without modifying code that depends on GCD. You can just replace import Dispatch with import DispatchAsync for most cases.

✅ Features

• DispatchQueue
  • Supports DispatchQueue.main, DispatchQueue.global(), and custom queues.
  • Provides async(_:) for asynchronous task submission using Swift Concurrency.
• DispatchWorkItem
  • Lightweight wrapper for units of concurrent work.
  • Can be submitted to queues or executed directly via async tasks.
• DispatchTime / DispatchWallTime
  • Minimal support for scheduling and time-based operations.
• DispatchSemaphore
  • Async-safe, non-blocking implementation for single-threaded WASM environments.
  • Balanced wait and signal required; assertions enforce correctness.
• Conditional Import Support
  • Seamless replacement for Dispatch when unavailable:

    #if os(WASI) && !canImport(Dispatch)
    import DispatchAsync
    #else
    import Dispatch
    #endif

• Cross-Platform Test Suite
  • Includes tests ported from the original libDispatch project.
  • Validates queue behavior, async scheduling, and semaphore semantics.
• SwiftPM Integration & Apache-2.0 License

📓 Notes

• Blocking APIs (e.g. sync) are not supported by design.
• DispatchSemaphore assumes single-threaded execution on WASM.
• Any unavoidable breaking API changes will be created following traditional semver rules with a bump in the major version of the package.