35 lines
930 B
Swift
35 lines
930 B
Swift
/// The importer can dismiss before delivering its result. Keep the target until
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/// completion, without a separate presentation flag that can drift from it.
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struct MobileFileImportState<Target> {
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private enum Phase {
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case presented(Target)
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case awaitingResult(Target)
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}
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private var phase: Phase?
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var isPresented: Bool {
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get {
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if case .presented = phase { return true }
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return false
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}
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set {
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if !newValue, case .presented(let target) = phase {
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phase = .awaitingResult(target)
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}
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}
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}
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mutating func present(for target: Target) {
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phase = .presented(target)
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}
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mutating func takeTarget() -> Target? {
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defer { phase = nil }
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switch phase {
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case .presented(let target), .awaitingResult(let target): return target
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case nil: return nil
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}
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}
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}
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