ObservedNativeFlow property wrapper

ObservedNativeFlow.swift

import Combine
import KMPNativeCoroutinesCore
import KMPNativeCoroutinesCombine
import SwiftUI

class ObservablePublisher<Output>: ObservableObject {
    @Published var value: Output
    
    init(_ publisher: AnyPublisher<Output, Never>, _ initialValue: Output) {
        value = initialValue
        publisher.receive(on: RunLoop.main).assign(to: &$value)
    }
}

@propertyWrapper
struct ObservedNativeFlow<Value, Output, Failure: Error, Unit>: DynamicProperty {
    @ObservedObject private var publisher: ObservablePublisher<Value>
    
    init(
        wrappedValue: Value,
        _ nativeFlow: @escaping NativeFlow<Output, Failure, Unit>,
        _ transform: (AnyPublisher<Output, Failure>) -> AnyPublisher<Value, Never>
    ) {
        let publisher = transform(createPublisher(for: nativeFlow))
        self.publisher = ObservablePublisher(publisher, wrappedValue)
    }
    
    var wrappedValue: Value {
        get {
            return publisher.value
        }
    }
}

View.swift

import SwiftUI
import NativeCoroutinesSampleShared

struct ClockView: View {
    @ObservedNativeFlow(Clock().timeNative, {
        $0.map { time -> String in
            let formatter = DateFormatter()
            formatter.setLocalizedDateFormatFromTemplate("HH:mm:ss")
            let date = Date(timeIntervalSince1970: time.doubleValue)
            return formatter.string(from: date)
        }
        .assertNoFailure()
        .eraseToAnyPublisher()
    }) var time: String = "--:--:--"
}