Eventually a EXC_BAD_ACCESS

EXC_BAD_ACCESS.swift

/* 
Eventually throws a EXC_BAD_ACCESS, reliably around iteration 130688, I think due to stack overflow.
https://share.cleanshot.com/qQdj9ygc
*/

import SwiftUI

@Observable
class MyObservableCounter {
    var value = 0
    
    func start() {
        value += 1
        DispatchQueue.main.asyncAfter(deadline: .now() + 0.01) {
            self.start()
        }
    }
}

class Owner {
    let counter = MyObservableCounter()
    
    func setup() {
        withObservationTracking(of: self.counter.value) { value in
            print("Counter changed to \(value)")
        }
        
        counter.start()
    }
}

struct ContentView: View {
 
    @State var owner = Owner()
    
    var body: some View {
        VStack {
            Text("Hello")
        }
        .onAppear {
            owner.setup()
        }
    }
}

// https://www.polpiella.dev/observable-outside-of-a-view
public func withObservationTracking<T>(of value: @escaping @autoclosure () -> T, execute: @escaping (T) -> Void) {
    Observation.withObservationTracking {
        execute(value())
    } onChange: {
        RunLoop.current.perform {
            withObservationTracking(of: value(), execute: execute)
        }
    }
}