unity-unitask-design

UniTask is a struct wrapping a pooled source, so awaiting the same UniTask variable twice throws InvalidOperationException. Call .Preserve() once to get a memoized copy that supports multiple awaits, or invoke the async method again for a fresh UniTask.

Use this.GetCancellationTokenOnDestroy(), available on MonoBehaviour, GameObject, and Component, and pass the token into every async call. Plain C# classes must own a CancellationTokenSource and cancel plus dispose it in their Dispose method.

No. UniTask.RunOnThreadPool, UniTask.Run, and SwitchToThreadPool throw NotSupportedException on WebGL because the platform is single-threaded. Guard those calls with #if UNITY_WEBGL && !UNITY_EDITOR and run the work synchronously as a fallback.

UniTask.Yield may resume on the same frame if awaited from an earlier PlayerLoop phase than the target timing. UniTask.NextFrame guarantees the continuation runs on a subsequent frame, making it the right choice for splitting work across frames.

A returned UniTask that is neither awaited nor .Forget()ed drops its result, and exceptions surface only through UniTaskScheduler.UnobservedTaskException. Always await the UniTask or call .Forget() with an exception handler for fire-and-forget work.

AsyncReactiveProperty suits a single mutable value whose changes subscribers observe, and it must be disposed to release subscribers. Channel<T> fits producer-consumer scenarios with independent rates, using Writer.TryWrite and Reader.ReadAllAsync for buffered consumption.