actor ImageDownloader { private enum CacheEntry { case inProgress(Task.Handle<Image, Error>) case ready(Image) } private var cache: [URL: CacheEntry] = [:] func image(from url: URL) async throws -> Image? { if let cached = cache[url] { switch cached { case .ready(let image): return image case .inProgress(let handle): return try await handle.get() } } let handle = async { try await downloadImage(from: url) } cache[url] = .inProgress(handle) do { let image = try await handle.get() cache[url] = .ready(image) return image } catch { cache[url] = nil throw error } } }

This appears to be fixed in Xcode 14.0 beta 2. I had to clean my build folder for it to start working though.

Using Reality Composer Pro, you can make a custom material that feeds the left and right images into a GeometrySwitchCameraIndexNode.

Use Group, with no more than 10 direct children in each Group. https://developer.apple.com/forums/thread/740677

This appears to be a bug in NSObject.KeyValueObservingPublisher. It's triggered because the values property only sends an initial Demand of .max(1) when it subscribes to the KVO publisher. Forcing a larger Demand works around the problem. We can use the handleEvents operator to send unlimited demand to the KVO publisher: Task { for await value in obj .publisher(for: \.count) .handleEvents(receiveSubscription: { $0.request(.unlimited) }) .values { print("async: \(value)") } }