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Type-erased Swift Task that cancels itself on deinit
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| /// A type-erased task that you can store in a collection | |
| /// to allow you to cancel at a later date. | |
| /// | |
| /// Upon deinit of the task, the task will be cancelled | |
| /// automatically. Similar to Combine's AnyCancellable. | |
| final class AnyTask { | |
| /// Call this cancellation block to cancel the task manually. | |
| let cancel: () -> Void | |
| /// Checks whether the task is cancelled. | |
| var isCancelled: Bool { isCancelledBlock() } | |
| private let isCancelledBlock: () -> Bool | |
| deinit { | |
| // On deinit, if the task is not cancelled then cancel it | |
| if !isCancelled { cancel() } | |
| } | |
| /// Constructs an AnyTask from the provided Task. | |
| /// The provided task is held strongly until AnyTask is | |
| /// deinitted. | |
| /// - Parameter task: The task to construct with. | |
| init<S, E>(_ task: Task<S, E>) { | |
| cancel = task.cancel | |
| isCancelledBlock = { task.isCancelled } | |
| } | |
| } | |
| extension Task { | |
| var eraseToAnyTask: AnyTask { .init(self) } | |
| } | |
| extension Array where Element == Task<Void, Never> { | |
| var erased: [AnyTask] { map(\.eraseToAnyTask) } | |
| } |
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That’s nice! But means there’s a dependency on Combine which is a system library and not a language library right?