iOSアプリ開発のためのThe Composable Architectureがすごく良いので紹介したい

iOSDC Japan 2020の発表資料です。The Composable Architecture v0.7.0についてのトークです。

# 参考URL

- https://fortee.jp/iosdc-japan-2020/proposal/40b59a33-1f0a-45ba-ba94-10ce9cf960f4
- https://github.com/pointfreeco/swift-composable-architecture
- https://www.pointfree.co/
- https://qiita.com/yimajo/items/77c204ab091223f9cb14

Transcript

1. iOSΞϓϦ։ൃͷͨΊͷ
   The Composable Architecture ͕
   ͘͢͝ྑ͍ͷͰ঺հ͍ͨ͠
   iOSDC Japan 2020 09/21 11:30 #iosdc #d
   ࠓ৓ળۣ / @yimajo
   

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2. iOSDC2020.9.21 11:30ͷൃදʹ
   ೖΕΒΕ͍ͯͳ͔ͬͨ಺༰ʹ͍ͭͯ
   ิ଍ͷͨΊʹ
   ௥هͨ͠ࢿྉʹͳ͍ͬͯ·͢
   ௥ه
   

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3. ࣗݾ঺հ͸͕࣌ؒ༨ͬͨΒޙ൒ʹ
   

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4. About The Composable Architecture
   

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5. About The Composable Architecture
   • A library for building applications
   • SwiftUI, UIKit
   • iOS, MacOS, tvOS, and WatchOS
   

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6. About The Composable Architecture
   • A library for building applications
   • SwiftUI, UIKit
   • iOS, MacOS, tvOS, and WatchOS
   • Point-Free hosted by Mr. Brandon and Mr. Stephen.
   • https://github.com/pointfreeco/swift-composable-architecture
   

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7. Point-Free
   ௥ه
   https://www.pointfree.co/
   

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8. What is
   The Composable
   Architecture
   

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9. State management
   

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10. Composition
    

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11. Side Effect
    

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12. Testable
    

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13. Ergonomics
    

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14. Basic Usage
    

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15. Main Parts
    • Action
    • Reducer
    • Effect
    • State
    • Store
    • Environment
    

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16. State
    Action
    Reducer
    Effect
    View
    Store
    

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17. State
    Action
    Reducer
    Effect
    View
    Store
    

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18. State
    Action
    Reducer
    Effect
    View
    Store
    

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19. State
    Action
    Reducer
    Effect
    View
    Store
    

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20. State
    Action
    Reducer
    Effect
    View
    Store
    

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21. State
    Action
    Reducer
    Effect
    View
    Store
    

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22. State
    Action
    Reducer
    Effect
    View
    Store
    

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23. State
    Action
    Reducer
    Effect
    View
    Store
    DI
    Environment
    

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24. αϯϓϧղઆ
    

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26. TCA
    

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27. Samples
    TCA
    

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28. Samples
    Swift Package Dependencies
    TCA
    

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29. ΍ΕΔ͜ͱ
    • - ͱ + ΛλοϓͰ͖Δ
    • ਺ࣈͷද͕ࣔ - ͱ + ʹΑΓมߋ͞ΕΔ
    ಛ௃
    • Effect ͕ͳ͍ɻEnvironment͸Χϥ
    CaseStudies/CounterDemo
    

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30. CaseStudies/CounterDemo
    State
    Action
    Reducer
    View
    Store
    

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31. CaseStudies/CounterDemo
    State
    Action
    Reducer
    View
    Store
    // Action
    enum CounterAction: Equatable {
    case decrementButtonTapped
    case incrementButtonTapped
    }
    

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32. CaseStudies/CounterDemo
    State
    Action
    Reducer
    View
    Store
    // Action
    enum CounterAction: Equatable {
    case decrementButtonTapped
    case incrementButtonTapped
    }
    // State
    struct CounterState: Equatable {
    var count = 0
    }
    

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33. CaseStudies/CounterDemo
    State
    Action
    Reducer
    View
    Store
    // Action
    enum CounterAction: Equatable {
    case decrementButtonTapped
    case incrementButtonTapped
    }
    // Reducer
    let counterReducer = Reducer { state, action, _ in
    switch action {
    case .decrementButtonTapped:
    state.count -= 1
    return .none
    case .incrementButtonTapped:
    state.count += 1
    return .none
    }
    }
    // State
    struct CounterState: Equatable {
    var count = 0
    }
    

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34. CaseStudies/CounterDemo
    State
    Action
    Reducer
    View
    Store
    // Action
    enum CounterAction: Equatable {
    case decrementButtonTapped
    case incrementButtonTapped
    }
    // Reducer
    let counterReducer = Reducer { state, action, _ in
    switch action {
    case .decrementButtonTapped:
    state.count -= 1
    return .none
    case .incrementButtonTapped:
    state.count += 1
    return .none
    }
    }
    // State
    struct CounterState: Equatable {
    var count = 0
    }
    struct CounterView: View {
    let store: Store
    var body: some View {
    WithViewStore(self.store) { viewStore in
    HStack {
    Button("−") {
    viewStore.send(.decrementButtonTapped)
    }
    Text(“\(viewStore.count)”)
    Button("+") {
    viewStore.send(.incrementButtonTapped)
    }
    }
    }
    

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35. ΍ΕΔ͜ͱ
    • 2ߦͷ- ͱ + ΛλοϓͰ͖ΔView͕2ͭ
    ಛ௃
    • Effect ͕ͳ͍ɻEnvironment͸Χϥ
    • Χ΢ϯλʔ༻ͷStoreͱViewΛͻͱͭͷ
    ෦඼ͱͯ͠2ߦར༻͍ͯ͠Δ
    CaseStudies/TwoCounterDemo
    

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36. CaseStudies/TwoCounterDemo
    State
    Action
    Reducer
    View
    Store
    

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37. CaseStudies/TwoCounterDemo
    State
    Action
    Reducer
    View
    Store
    // Action
    enum TwoCountersAction {
    case counter1(CounterAction)
    case counter2(CounterAction)
    }
    

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38. CaseStudies/TwoCounterDemo
    State
    Action
    Reducer
    View
    Store
    // Action
    enum TwoCountersAction {
    case counter1(CounterAction)
    case counter2(CounterAction)
    }
    // State
    struct TwoCountersState: Equatable {
    var counter1 = CounterState()
    var counter2 = CounterState()
    }
    

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39. CaseStudies/TwoCounterDemo
    State
    Action
    Reducer
    View
    Store
    // Action
    enum TwoCountersAction {
    case counter1(CounterAction)
    case counter2(CounterAction)
    }
    // Reducer
    let twoCountersReducer = Reducer
    .combine(
    counterReducer.pullback(
    state: \TwoCountersState.counter1,
    action: /TwoCountersAction.counter1,
    environment: { _ in CounterEnvironment() }
    ),
    counterReducer.pullback(
    state: \TwoCountersState.counter2,
    action: /TwoCountersAction.counter2,
    environment: { _ in CounterEnvironment() }
    )
    )
    // State
    struct TwoCountersState: Equatable {
    var counter1 = CounterState()
    var counter2 = CounterState()
    }
    

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40. struct TwoCountersView: View {
    let store: Store
    var body: some View {
    Form {
    Section(header: Text(template: readMe, .caption)) {
    HStack {
    Text("Counter 1")
    CounterView(
    store: self.store.scope(state: { $0.counter1 }, action: TwoCountersAction.counter1)
    )
    .buttonStyle(BorderlessButtonStyle())
    .frame(maxWidth: .infinity, maxHeight: .infinity, alignment: .trailing)
    }
    HStack {
    Text("Counter 2")
    CounterView(
    store: self.store.scope(state: { $0.counter2 }, action: TwoCountersAction.counter2)
    )
    .buttonStyle(BorderlessButtonStyle())
    .frame(maxWidth: .infinity, maxHeight: .infinity, alignment: .trailing)
    }
    }
    }
    .navigationBarTitle("Two counter demo")
    }
    }
    

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41. ΍ΕΔ͜ͱ
    • - ͱ + ΛλοϓͰ͖Δ
    • - λοϓ͢Δͱ1ඵޙʹ+͞ΕΔ
    • Number factϘλϯΛλοϓͰWeb APIݺͼग़͠
    ಛ௃
    • Effect ͕2ͭ͋Γɺ- Ϙλϯλοϓͱ NumberFact
    ϘλϯʹΑΓಈ࡞͢Δɻ
    CaseStudies/EffectBasics
    

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42. CaseStudies/EffectBasics
    State
    Action
    Reducer
    View
    Store
    Environment
    Effect
    

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43. CaseStudies/EffectBasics
    State
    Action
    Reducer
    View
    Store
    Environment
    // Action
    enum EffectsBasicsAction: Equatable {
    case decrementButtonTapped
    case incrementButtonTapped
    case numberFactButtonTapped
    case numberFactResponse (
    Result
    )
    }
    Effect
    

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44. CaseStudies/EffectBasics
    State
    Action
    Reducer
    View
    Store
    // State
    struct EffectsBasicsState: Equatable {
    var count = 0
    // ௨৴தΛࣔ͢ϑϥά
    var isNumberFactRequestInFlight = false
    // WebAPIͷϨεϙϯε
    var numberFact: String?
    }
    Environment
    // Action
    enum EffectsBasicsAction: Equatable {
    case decrementButtonTapped
    case incrementButtonTapped
    case numberFactButtonTapped
    case numberFactResponse (
    Result
    )
    }
    Effect
    

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45. CaseStudies/EffectBasics
    State
    Action
    Reducer
    View
    Store
    // State
    struct EffectsBasicsState: Equatable {
    var count = 0
    // ௨৴தΛࣔ͢ϑϥά
    var isNumberFactRequestInFlight = false
    // WebAPIͷϨεϙϯε
    var numberFact: String?
    }
    Environment
    // Action
    enum EffectsBasicsAction: Equatable {
    case decrementButtonTapped
    case incrementButtonTapped
    case numberFactButtonTapped
    case numberFactResponse (
    Result
    )
    }
    Effect
    // Reducer
    let effectsBasicsReducer = Reducer { state, action, environment in
    switch action {
    case .decrementButtonTapped:
    ɾɾɾলུ
    return Effect(value: EffectsBasicsAction.incrementButtonTapped)
    .delay(for: 1, scheduler: environment.mainQueue)
    .eraseToEffect()
    case .incrementButtonTapped:
    ɾɾɾলུ
    return .none
    case .numberFactButtonTapped:
    state.isNumberFactRequestInFlight = true
    state.numberFact = nil
    return environment.numberFact(state.count)
    .receive(on: environment.mainQueue)
    .catchToEffect()
    .map(EffectsBasicsAction.numberFactResponse)
    case let .numberFactResponse(.success(response)):
    state.isNumberFactRequestInFlight = false
    state.numberFact = response
    return .none
    case .numberFactResponse(.failure):
    ɾɾɾলུ
    return .none
    }
    }
    

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46. CaseStudies/EffectBasics
    State
    Action
    Reducer
    View
    Store
    // State
    struct EffectsBasicsState: Equatable {
    var count = 0
    // ௨৴தΛࣔ͢ϑϥά
    var isNumberFactRequestInFlight = false
    // WebAPIͷϨεϙϯε
    var numberFact: String?
    }
    Environment
    // Action
    enum EffectsBasicsAction: Equatable {
    case decrementButtonTapped
    case incrementButtonTapped
    case numberFactButtonTapped
    case numberFactResponse (
    Result
    )
    }
    Effect
    // Reducer
    let effectsBasicsReducer = Reducer { state, action, environment in
    switch action {
    case .decrementButtonTapped:
    ɾɾɾলུ
    return Effect(value: EffectsBasicsAction.incrementButtonTapped)
    .delay(for: 1, scheduler: environment.mainQueue)
    .eraseToEffect()
    case .incrementButtonTapped:
    ɾɾɾলུ
    return .none
    case .numberFactButtonTapped:
    state.isNumberFactRequestInFlight = true
    state.numberFact = nil
    return environment.numberFact(state.count)
    .receive(on: environment.mainQueue)
    .catchToEffect()
    .map(EffectsBasicsAction.numberFactResponse)
    case let .numberFactResponse(.success(response)):
    state.isNumberFactRequestInFlight = false
    state.numberFact = response
    return .none
    case .numberFactResponse(.failure):
    ɾɾɾলུ
    return .none
    }
    }
    

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47. CaseStudies/EffectBasics
    State
    Action
    Reducer
    View
    Store
    // State
    struct EffectsBasicsState: Equatable {
    var count = 0
    // ௨৴தΛࣔ͢ϑϥά
    var isNumberFactRequestInFlight = false
    // WebAPIͷϨεϙϯε
    var numberFact: String?
    }
    Environment
    // Action
    enum EffectsBasicsAction: Equatable {
    case decrementButtonTapped
    case incrementButtonTapped
    case numberFactButtonTapped
    case numberFactResponse (
    Result
    )
    }
    Effect
    // Reducer
    let effectsBasicsReducer = Reducer { state, action, environment in
    switch action {
    case .decrementButtonTapped:
    ɾɾɾলུ
    return Effect(value: EffectsBasicsAction.incrementButtonTapped)
    .delay(for: 1, scheduler: environment.mainQueue)
    .eraseToEffect()
    case .incrementButtonTapped:
    ɾɾɾলུ
    return .none
    case .numberFactButtonTapped:
    state.isNumberFactRequestInFlight = true
    state.numberFact = nil
    return environment.numberFact(state.count)
    .receive(on: environment.mainQueue)
    .catchToEffect()
    .map(EffectsBasicsAction.numberFactResponse)
    case let .numberFactResponse(.success(response)):
    state.isNumberFactRequestInFlight = false
    state.numberFact = response
    return .none
    case .numberFactResponse(.failure):
    ɾɾɾলུ
    return .none
    }
    }
    

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48. ͜͜·ͰΛ੔ཧ
    

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49. ͜͜·ͰΛ੔ཧ
    • StateΛมߋͰ͖Δͷ͸ReducerͷΈͱ͍͏੍໿Λ՝͢͜ͱ͕Ͱ͖Δ
    

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50. ͜͜·ͰΛ੔ཧ
    • StateΛมߋͰ͖Δͷ͸ReducerͷΈͱ͍͏੍໿Λ՝͢͜ͱ͕Ͱ͖Δ
    • ViewͱϩδοΫΛͻͱ·ͱ·Γͷ෦඼ͱͯ͠૊Έ߹ΘͤΒΕΔ
    

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51. ͜͜·ͰΛ੔ཧ
    • StateΛมߋͰ͖Δͷ͸ReducerͷΈͱ͍͏੍໿Λ՝͢͜ͱ͕Ͱ͖Δ
    • ViewͱϩδοΫΛͻͱ·ͱ·Γͷ෦඼ͱͯ͠૊Έ߹ΘͤΒΕΔ
    • େ͖ͳReducerΛ࡞Βͳͯ͘ྑ͍
    

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52. ͜͜·ͰΛ੔ཧ
    • StateΛมߋͰ͖Δͷ͸ReducerͷΈͱ͍͏੍໿Λ՝͢͜ͱ͕Ͱ͖Δ
    • ViewͱϩδοΫΛͻͱ·ͱ·Γͷ෦඼ͱͯ͠૊Έ߹ΘͤΒΕΔ
    • େ͖ͳReducerΛ࡞Βͳͯ͘ྑ͍
    • ෭࡞༻͸Effectܕʹ͠ɺ࣍ͷΞΫγϣϯΛݺͼग़ͤΔ
    

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53. αϯϓϧίʔυ
    ͷิ଍
    

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54. WithViewStore
    &
    ViewStore
    㚎
    㚎
    

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55. public struct WithViewStore: View where Content: View {
    private let content: (ViewStore) -> Content
    private var prefix: String?
    @ObservedObject private var viewStore: ViewStore
    public init(
    _ store: Store,
    removeDuplicates isDuplicate: @escaping (State, State) -> Bool,
    @ViewBuilder content: @escaping (ViewStore) -> Content
    ) {
    self.content = content
    self.viewStore = ViewStore(store, removeDuplicates: isDuplicate)
    }
    public var body: some View {
    … লུ
    return self.content(self.viewStore)
    }
    

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56. public struct WithViewStore: View where Content: View {
    private let content: (ViewStore) -> Content
    private var prefix: String?
    @ObservedObject private var viewStore: ViewStore
    public init(
    _ store: Store,
    removeDuplicates isDuplicate: @escaping (State, State) -> Bool,
    @ViewBuilder content: @escaping (ViewStore) -> Content
    ) {
    self.content = content
    self.viewStore = ViewStore(store, removeDuplicates: isDuplicate)
    }
    public var body: some View {
    … লུ
    return self.content(self.viewStore)
    }
    

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57. public struct WithViewStore: View where Content: View {
    private let content: (ViewStore) -> Content
    private var prefix: String?
    @ObservedObject private var viewStore: ViewStore
    public init(
    _ store: Store,
    removeDuplicates isDuplicate: @escaping (State, State) -> Bool,
    @ViewBuilder content: @escaping (ViewStore) -> Content
    ) {
    self.content = content
    self.viewStore = ViewStore(store, removeDuplicates: isDuplicate)
    }
    public var body: some View {
    … লུ
    return self.content(self.viewStore)
    }
    

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58. @dynamicMemberLookup
    public final class ViewStore: ObservableObject {
    … লུ
    /// The current state.
    public private(set) var state: State {
    willSet {
    self.objectWillChange.send()
    }
    }
    … লུ
    public func send(_ action: Action) {
    self._send(action)
    }
    

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59. Effect
    

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60. public struct Effect: Publisher
    

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61. • Combine.Publisherʹ४ڌ
    public struct Effect: Publisher
    

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62. • Combine.Publisherʹ४ڌ
    • PublisherͳͷͰTCA಺෦ͰSubscriber؂ࢹͰ͖Δ
    public struct Effect: Publisher
    

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63. • Combine.Publisherʹ४ڌ
    • PublisherͳͷͰTCA಺෦ͰSubscriber؂ࢹͰ͖Δ
    • ΦϖϨʔλͰϝιουνΣΠϯͰ͖Δ
    public struct Effect: Publisher
    

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64. Effect Examples
    https://github.com/pointfreeco/swift-composable-architecture/blob/0.7.0/Sources/
    ComposableArchitecture/Effect.swift
    ௥ه
    

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65. Effect(
    NotificationCenter.default
    .publisher(for: UIApplication.userDidTakeScreenshotNotification)
    )
    NotificationCenter.default
    .publisher(for: UIApplication.userDidTakeScreenshotNotification)
    .eraseToEffect()
    ௥ه
    

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66. Effect.future { callback in
    DispatchQueue.main.asyncAfter(deadline: .now() + 1) {
    callback(.success(42))
    }
    }
    ௥ه
    

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67. Effect.result {
    let fileUrl = URL(
    fileURLWithPath: NSSearchPathForDirectoriesInDomains(
    .documentDirectory,
    .userDomainMask,
    true
    )[0]
    )
    .appendingPathComponent("user.json")
    let result = Result {
    let data = try Data(contentsOf: fileUrl)
    return try JSONDecoder().decode(User.self, from: $0)
    }
    return result
    }
    ௥ه
    

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68. EffectܕΛ؂ࢹͯ࣍͠ͷActionΛݺͼग़͢࢓૊Έ
    

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69. • Store͸ViewStore͔ΒActionΛݺͼग़͞ΕΔͱɺݱࡏͷActionͷ
    Ωϡʔʹ௥Ճ
    EffectܕΛ؂ࢹͯ࣍͠ͷActionΛݺͼग़͢࢓૊Έ
    

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70. • Store͸ViewStore͔ΒActionΛݺͼग़͞ΕΔͱɺݱࡏͷActionͷ
    Ωϡʔʹ௥Ճ
    • ΩϡʔΛwhileϧʔϓͯ͠ActionΛॱ࣮࣍ߦ͠
    EffectܕΛ؂ࢹͯ࣍͠ͷActionΛݺͼग़͢࢓૊Έ
    

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71. • Store͸ViewStore͔ΒActionΛݺͼग़͞ΕΔͱɺݱࡏͷActionͷ
    Ωϡʔʹ௥Ճ
    • ΩϡʔΛwhileϧʔϓͯ͠ActionΛॱ࣮࣍ߦ͠
    • ͦΕʹඥͮ͘EffectΛߪಡॲཧ͍ͯ͘͠
    EffectܕΛ؂ࢹͯ࣍͠ͷActionΛݺͼग़͢࢓૊Έ
    

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72. • Store͸ViewStore͔ΒActionΛݺͼग़͞ΕΔͱɺݱࡏͷActionͷ
    Ωϡʔʹ௥Ճ
    • ΩϡʔΛwhileϧʔϓͯ͠ActionΛॱ࣮࣍ߦ͠
    • ͦΕʹඥͮ͘EffectΛߪಡॲཧ͍ͯ͘͠
    • EffectΛߪಡ͢Δͱ݁Ռͱͯ࣍͠ͷActionΛݺͼग़͢
    EffectܕΛ؂ࢹͯ࣍͠ͷActionΛݺͼग़͢࢓૊Έ
    

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73. ςετίʔυ
    

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74. State
    Action
    Reducer
    Environment
    Effect
    TestStore
    Scheduler
    

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75. State
    Action
    Reducer
    Environment
    Effect
    TestStore
    Scheduler
    SUT
    

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76. State
    Action
    Reducer
    Environment
    Effect
    TestStore
    Scheduler
    SUT
    

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77. State
    Action
    Reducer
    Environment
    Effect
    TestStore
    Scheduler Test Double
    SUT
    

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78. State
    Action
    Reducer
    Environment
    Effect
    TestStore
    Scheduler Test Double
    SUT
    

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79. State
    Action
    Reducer
    Environment
    Effect
    TestStore
    Scheduler Test Double
    Test Double
    SUT
    

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80. func testNumberFact() {
    let store = TestStore(
    initialState: EffectsBasicsState(),
    reducer: effectsBasicsReducer,
    environment: EffectsBasicsEnvironment(
    mainQueue: self.scheduler.eraseToAnyScheduler(),
    numberFact: { n in Effect(value: "\(n) is a good number") }
    )
    )
    store.assert(
    .send(.incrementButtonTapped) {
    $0.count = 1
    },
    .send(.numberFactButtonTapped) {
    $0.isNumberFactRequestInFlight = true
    },
    .do { self.scheduler.advance(by: 1) },
    .receive(.numberFactResponse(.success("1 is a good number"))) {
    $0.isNumberFactRequestInFlight = false
    $0.numberFact = "1 is a good number"
    }
    )
    }
    

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81. func testNumberFact() {
    let store = TestStore(
    initialState: EffectsBasicsState(),
    reducer: effectsBasicsReducer,
    environment: EffectsBasicsEnvironment(
    mainQueue: self.scheduler.eraseToAnyScheduler(),
    numberFact: { n in Effect(value: "\(n) is a good number") }
    )
    )
    store.assert(
    .send(.incrementButtonTapped) {
    $0.count = 1
    },
    .send(.numberFactButtonTapped) {
    $0.isNumberFactRequestInFlight = true
    },
    .do { self.scheduler.advance(by: 1) },
    .receive(.numberFactResponse(.success("1 is a good number"))) {
    $0.isNumberFactRequestInFlight = false
    $0.numberFact = "1 is a good number"
    }
    )
    }
    

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82. func testNumberFact() {
    let store = TestStore(
    initialState: EffectsBasicsState(),
    reducer: effectsBasicsReducer,
    environment: EffectsBasicsEnvironment(
    mainQueue: self.scheduler.eraseToAnyScheduler(),
    numberFact: { n in Effect(value: "\(n) is a good number") }
    )
    )
    store.assert(
    .send(.incrementButtonTapped) {
    $0.count = 1
    },
    .send(.numberFactButtonTapped) {
    $0.isNumberFactRequestInFlight = true
    },
    .do { self.scheduler.advance(by: 1) },
    .receive(.numberFactResponse(.success("1 is a good number"))) {
    $0.isNumberFactRequestInFlight = false
    $0.numberFact = "1 is a good number"
    }
    )
    }
    

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83. func testNumberFact() {
    let store = TestStore(
    initialState: EffectsBasicsState(),
    reducer: effectsBasicsReducer,
    environment: EffectsBasicsEnvironment(
    mainQueue: self.scheduler.eraseToAnyScheduler(),
    numberFact: { n in Effect(value: "\(n) is a good number") }
    )
    )
    store.assert(
    .send(.incrementButtonTapped) {
    $0.count = 1
    },
    .send(.numberFactButtonTapped) {
    $0.isNumberFactRequestInFlight = true
    },
    .do { self.scheduler.advance(by: 1) },
    .receive(.numberFactResponse(.success("1 is a good number"))) {
    $0.isNumberFactRequestInFlight = false
    $0.numberFact = "1 is a good number"
    }
    )
    }
    $0.count Λ 1 count ͸ 1
    -> ࣗ෼͕ظ଴͢ΔState
    ࣮ࡍʹมߋ͞ΕͨState
    ͱൺֱ
    

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84. func testNumberFact() {
    let store = TestStore(
    initialState: EffectsBasicsState(),
    reducer: effectsBasicsReducer,
    environment: EffectsBasicsEnvironment(
    mainQueue: self.scheduler.eraseToAnyScheduler(),
    numberFact: { n in Effect(value: "\(n) is a good number") }
    )
    )
    store.assert(
    .send(.incrementButtonTapped) {
    $0.count = 1
    },
    .send(.numberFactButtonTapped) {
    $0.isNumberFactRequestInFlight = true
    },
    .do { self.scheduler.advance(by: 1) },
    .receive(.numberFactResponse(.success("1 is a good number"))) {
    $0.isNumberFactRequestInFlight = false
    $0.numberFact = "1 is a good number"
    }
    )
    }
    $0.count Λ 1 count ͸ 1
    -> ࣗ෼͕ظ଴͢ΔState
    ࣮ࡍʹมߋ͞ΕͨState
    ͱൺֱ
    

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85. func testNumberFact() {
    let store = TestStore(
    initialState: EffectsBasicsState(),
    reducer: effectsBasicsReducer,
    environment: EffectsBasicsEnvironment(
    mainQueue: self.scheduler.eraseToAnyScheduler(),
    numberFact: { n in Effect(value: "\(n) is a good number") }
    )
    )
    store.assert(
    .send(.incrementButtonTapped) {
    $0.count = 1
    },
    .send(.numberFactButtonTapped) {
    $0.isNumberFactRequestInFlight = true
    },
    .do { self.scheduler.advance(by: 1) },
    .receive(.numberFactResponse(.success("1 is a good number"))) {
    $0.isNumberFactRequestInFlight = false
    $0.numberFact = "1 is a good number"
    }
    )
    }
    $0.count Λ 1 count ͸ 1
    -> ࣗ෼͕ظ଴͢ΔState
    ࣮ࡍʹมߋ͞ΕͨState
    ͱൺֱ
    

    View Slide

86. func testNumberFact() {
    let store = TestStore(
    initialState: EffectsBasicsState(),
    reducer: effectsBasicsReducer,
    environment: EffectsBasicsEnvironment(
    mainQueue: self.scheduler.eraseToAnyScheduler(),
    numberFact: { n in Effect(value: "\(n) is a good number") }
    )
    )
    store.assert(
    .send(.incrementButtonTapped) {
    $0.count = 1
    },
    .send(.numberFactButtonTapped) {
    $0.isNumberFactRequestInFlight = true
    },
    .do { self.scheduler.advance(by: 1) },
    .receive(.numberFactResponse(.success("1 is a good number"))) {
    $0.isNumberFactRequestInFlight = false
    $0.numberFact = "1 is a good number"
    }
    )
    }
    $0.count Λ 1 count ͸ 1
    -> ࣗ෼͕ظ଴͢ΔState
    ࣮ࡍʹมߋ͞ΕͨState
    ͱൺֱ
    ෭࡞༻ͷ݁Ռɺ"DUJPO͕ड͚औΔظ଴஋
    

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87. func testNumberFact() {
    let store = TestStore(
    initialState: EffectsBasicsState(),
    reducer: effectsBasicsReducer,
    environment: EffectsBasicsEnvironment(
    mainQueue: self.scheduler.eraseToAnyScheduler(),
    numberFact: { n in Effect(value: "\(n) is a good number") }
    )
    )
    store.assert(
    .send(.incrementButtonTapped) {
    $0.count = 1
    },
    .send(.numberFactButtonTapped) {
    $0.isNumberFactRequestInFlight = true
    },
    .do { self.scheduler.advance(by: 1) },
    .receive(.numberFactResponse(.success("1 is a good number"))) {
    $0.isNumberFactRequestInFlight = false
    $0.numberFact = "1 is a good number"
    }
    )
    }
    $0.count Λ 1 count ͸ 1
    -> ࣗ෼͕ظ଴͢ΔState
    ࣮ࡍʹมߋ͞ΕͨState
    ͱൺֱ
    ෭࡞༻ͷ݁Ռɺ"DUJPO͕ड͚औΔظ଴஋
    -> ࣗ෼͕ظ଴͢ΔState
    

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88. TCAͷςετίʔυʹ͍ͭͯͷ੔ཧ
    

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89. TCAͷςετίʔυʹ͍ͭͯͷ੔ཧ
    • TCA͸Reducer༻ͷςετํ๏Λఏڙͯ͘͠ΕͯΔ
    

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90. TCAͷςετίʔυʹ͍ͭͯͷ੔ཧ
    • TCA͸Reducer༻ͷςετํ๏Λఏڙͯ͘͠ΕͯΔ
    • Reducer༻ͷςετͰ͸Effect͸ςετμϒϧͱͯ͠ஔ͖׵͑ɺผ
    ్୯ମςετॻ͍ͨΒ͍͍
    

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91. TCAͷςετίʔυʹ͍ͭͯͷิ଍
    expectedState actualState
    ൺֱ
    

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92. TCAʹ͍ͭͯ
    ·ͱΊ
    

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93. ྑ͍ͱ͜Ζ
    

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94. ྑ͍ͱ͜Ζ
    • Reducer͔͠StateΛѻ͑ͳ͍ͱ͍͏੍໿͕͋Δ
    

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95. ྑ͍ͱ͜Ζ
    • Reducer͔͠StateΛѻ͑ͳ͍ͱ͍͏੍໿͕͋Δ
    • ReducerΛ෼ׂͰ͖ΔͨΊɺେ͖ͳReducerΛ࡞Βͳ͍͍ͯ͘
    

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96. ྑ͍ͱ͜Ζ
    • Reducer͔͠StateΛѻ͑ͳ͍ͱ͍͏੍໿͕͋Δ
    • ReducerΛ෼ׂͰ͖ΔͨΊɺେ͖ͳReducerΛ࡞Βͳ͍͍ͯ͘
    • SwiftUIͰ΋࢖͍΍͍͢
    

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97. ྑ͍ͱ͜Ζ
    • Reducer͔͠StateΛѻ͑ͳ͍ͱ͍͏੍໿͕͋Δ
    • ReducerΛ෼ׂͰ͖ΔͨΊɺେ͖ͳReducerΛ࡞Βͳ͍͍ͯ͘
    • SwiftUIͰ΋࢖͍΍͍͢
    • TCAΛѻ͏ࡍʹCombineΛ͋Μ·Γཧղͯ͠ͳͯ͘΋࣮ߦͱ؂ࢹͷԸ
    ܙ͕͋Δ
    

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98. ྑ͍ͱ͜Ζ
    • Reducer͔͠StateΛѻ͑ͳ͍ͱ͍͏੍໿͕͋Δ
    • ReducerΛ෼ׂͰ͖ΔͨΊɺେ͖ͳReducerΛ࡞Βͳ͍͍ͯ͘
    • SwiftUIͰ΋࢖͍΍͍͢
    • TCAΛѻ͏ࡍʹCombineΛ͋Μ·Γཧղͯ͠ͳͯ͘΋࣮ߦͱ؂ࢹͷԸ
    ܙ͕͋Δ
    • ςετεέδϡʔϥͱςετํ๏Λఏڙͯ͘͠Ε͍ͯΔ
    

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99. ೉͍͠ͱ͜Ζ
    

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100. ೉͍͠ͱ͜Ζ
     • ͋Δఔ౓CombineΛཧղ͠ͳ͍ͱTCAΛཧղͮ͠Β͍
     

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101. ೉͍͠ͱ͜Ζ
     • ͋Δఔ౓CombineΛཧղ͠ͳ͍ͱTCAΛཧղͮ͠Β͍
     • Combine͕OSS͡Όͳ͍ͨΊCombineࣗମͷίʔυ͸ಡΊͳ͍
     

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102. ೉͍͠ͱ͜Ζ
     • ͋Δఔ౓CombineΛཧղ͠ͳ͍ͱTCAΛཧղͮ͠Β͍
     • Combine͕OSS͡Όͳ͍ͨΊCombineࣗମͷίʔυ͸ಡΊͳ͍
     • جຊతʹ͸ΞϓϦઃܭ͸TCAͰ΍Γ͖Βͳ͍ͱ͍͚ͳ͍ʢؾ͕͢
     Δʣɻ
     

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103. ͞Βʹৄ͍͠৘ใ͸
     

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104. https://qiita.com/yimajo/items/77c204ab091223f9cb14
     QiitaʹهࣄΛॻ͍͍ͯ·͢
     

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105. 2020/09/21 14:40ʙ Track B ϨΪϡϥʔτʔΫʢ40෼ʣ
     TCAҎ֎ͷؔ਺ܕͳϑϨʔϜϫʔΫʹ͍ͭͯ஌Γ͍ͨͳΒ
     ͜ͷޙͷτʔΫʹظ଴͠·͠ΐ͏
     

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106. ࣗݾ঺հ
     

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107. ը૾Ҿ༻ݩ: ͓Ͱ͔͚ମݧܕϝσΟΞSPOT
     ʰ஑ାʹര஀ͨ͠α΢φͷָԂʮ͔Δ·Δʯ͕ྑ͗ͯ͢ҰੜՈʹؼΕͳ͍͔΋͠Εͳ͍ ʱ
     https://travel.spot-app.jp/karumaru_yoppy/
     

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108. • ࠓ৓ળۣʢ͍·͡ΐ͏ Α͠ͷΓʣ
     ը૾Ҿ༻ݩ: ͓Ͱ͔͚ମݧܕϝσΟΞSPOT
     ʰ஑ାʹര஀ͨ͠α΢φͷָԂʮ͔Δ·Δʯ͕ྑ͗ͯ͢ҰੜՈʹؼΕͳ͍͔΋͠Εͳ͍ ʱ
     https://travel.spot-app.jp/karumaru_yoppy/
     

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109. • ࠓ৓ળۣʢ͍·͡ΐ͏ Α͠ͷΓʣ
     • ΞΧ΢ϯτ͸େ఍ y.imajo ͱ͔
     yimajo
     ը૾Ҿ༻ݩ: ͓Ͱ͔͚ମݧܕϝσΟΞSPOT
     ʰ஑ାʹര஀ͨ͠α΢φͷָԂʮ͔Δ·Δʯ͕ྑ͗ͯ͢ҰੜՈʹؼΕͳ͍͔΋͠Εͳ͍ ʱ
     https://travel.spot-app.jp/karumaru_yoppy/
     

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110. • ࠓ৓ળۣʢ͍·͡ΐ͏ Α͠ͷΓʣ
     • ΞΧ΢ϯτ͸େ఍ y.imajo ͱ͔
     yimajo
     • גࣜձࣾΩϡϦΦγςΟιϑτ
     ΢ΣΞΛҰਓͰ΍͍ͬͯ·͢
     ը૾Ҿ༻ݩ: ͓Ͱ͔͚ମݧܕϝσΟΞSPOT
     ʰ஑ାʹര஀ͨ͠α΢φͷָԂʮ͔Δ·Δʯ͕ྑ͗ͯ͢ҰੜՈʹؼΕͳ͍͔΋͠Εͳ͍ ʱ
     https://travel.spot-app.jp/karumaru_yoppy/
     

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111. • ࠓ৓ળۣʢ͍·͡ΐ͏ Α͠ͷΓʣ
     • ΞΧ΢ϯτ͸େ఍ y.imajo ͱ͔
     yimajo
     • גࣜձࣾΩϡϦΦγςΟιϑτ
     ΢ΣΞΛҰਓͰ΍͍ͬͯ·͢
     • ͓͢͢Ίͷα΢φ͸஑ାͷʮ͔Δ
     ·Δʯ
     ը૾Ҿ༻ݩ: ͓Ͱ͔͚ମݧܕϝσΟΞSPOT
     ʰ஑ାʹര஀ͨ͠α΢φͷָԂʮ͔Δ·Δʯ͕ྑ͗ͯ͢ҰੜՈʹؼΕͳ͍͔΋͠Εͳ͍ ʱ
     https://travel.spot-app.jp/karumaru_yoppy/
     

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112. pixiv / BOOTHͰిࢠॻ੶Λൢച͍ͯ͠·͢
     https://swift.booth.pm/
     • async/await ݚڀಡຊ (iOSDC 2018)
     • RxSwift ݚڀಡຊ1~4 (iOSDC 2019)
     • VIPER ݚڀಡຊ
     • SwiftUI ΨΠυϒοΫ
     • Combine ΨΠυϒοΫ (iOSDC 2020)
     

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113. ݱঢ়ܧଓதͷ࢓ࣄ
     • IoTͷʮ·͝νϟϯωϧʯͱ͍͏
     ੡඼ͷiOSΞϓϦ։ൃΛख఻ͬͯ
     ͍·͢
     • SwiftUI൛΋࡞ͬͯͨΓ͠·͢
     

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114. ࠷ۙҰ೥Ҏ಺ͷ
     աڈͷ࢓ࣄ
     • ʮϚωʔϑΥϫʔυΫϥ΢υձ
     ܭʯͱ͍͏iOSΞϓϦ։ൃΛख
     ఻͍ͬͯ·ͨ͠
     

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115. Ҋ݅Λืू͍ͯ͠·͢
     

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116. • ΋͠ɺSwiftUIΛ࢖ͬͯΞϓϦ։ൃΛख఻ͬͯ΄͍͠૊৫/๏ਓ͕͍
     Ε͹ख఻͏ͷͰ͝࿈བྷ͍ͩ͘͞
     Ҋ݅Λืू͍ͯ͠·͢
     

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117. • ΋͠ɺSwiftUIΛ࢖ͬͯΞϓϦ։ൃΛख఻ͬͯ΄͍͠૊৫/๏ਓ͕͍
     Ε͹ख఻͏ͷͰ͝࿈བྷ͍ͩ͘͞
     • ΋͠ɺςετίʔυΛॻ͍͍ͯ͘จԽΛࠜ෇͔͍ͤͨͱ͍͏૊৫/๏
     ਓ͕͍Ε͹ॏཁੑͱָ͠͞Λਁಁͤ͞Δख఻͍΋Ͱ͖Δͱࢥ͏ͷ
     Ͱɺ͝࿈བྷ͍ͩ͘͞
     Ҋ݅Λืू͍ͯ͠·͢
     

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118. ࠷ޙ·Ͱ͝ཡ͍͖ͨͩ
     ͋Γ͕ͱ͏͍͟͝·ͨ͠
     @yimajo
     

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