Memory and ARC

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In a live coding session you're handed the following Combine ViewModel. Add a feature that subscribes to the price stream and reflects it in priceText, and explain, with code, how you'd handle unsubscribing.

final class ProductViewModel {
    @Published var priceText = ""
    private let priceStream: AnyPublisher<Decimal, Never>
    init(priceStream: AnyPublisher<Decimal, Never>) {
        self.priceStream = priceStream
    }
}

Your answer

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See the short answer

Store the sink result in a Set<AnyCancellable> property. When the ViewModel is deallocated the cancellables deinit and the subscription cancels itself; if you keep it in a local variable, the subscription ends as soon as the function returns.

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