@StateObject passing rules

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import SwiftUI
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class Manager: ObservableObject {
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    @Published var cnt: Int = 0
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}
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class Manager2: ObservableObject {
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    @ObservedObject var m: Manager;
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    init(m: Manager) {
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        self.m = m
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    }
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    func f() {
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        self.m.cnt += 1
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    }
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}
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struct ViewB: View {
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    @ObservedObject var m: Manager
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    @ObservedObject var m2: Manager2
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    init(m: Manager) {
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        print("init")
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        self.m = m
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        self.m2 = .init(m: m)
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    }
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    var body: some View {
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        Button(action: {
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            print("Clicked")
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            self.m2.f()
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            print("After Clicked")
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        }) {
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            Text("Click me")
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                .font(.system(size: 40))
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        }
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    }
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}
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struct ContentView: View {
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    @ObservedObject var m = Manager();
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    var body: some View {
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        ViewB(m: self.m)
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    }
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}
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#Preview {
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    ContentView()
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}

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import SwiftUI
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class Manager: ObservableObject {
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    @Published var cnt: Int = 0
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}
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class Manager2: ObservableObject {
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    var m = Manager();
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    init() {
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    }
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    func f() {
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        self.m.cnt += 1
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    }
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}
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struct ViewB: View {
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    @ObservedObject var m2: Manager2
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    @ObservedObject var m: Manager
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    var printer = DeallocPrinter()
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    var body: some View {
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        Button(action: {
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            print("***\nClicked")
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            self.m2.f()
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            print(self.m.cnt)
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            print("After Clicked")
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        }) {
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            Text("\(self.m.cnt)")
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                .font(.system(size: 40))
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        }
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    }
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}
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class DeallocPrinter {
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    deinit {
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        print("deallocated")
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    }
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}
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struct ContentView: View {
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    @StateObject private var m2: Manager2
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    init() {
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        self._m2 = StateObject(wrappedValue: Manager2())
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    }
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    var body: some View {
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        ViewB(m2: self.m2, m: self.m2.m)
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    }
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}
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#Preview {
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    ContentView()
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}