timer-example-1-cancel-nil

import Combine
import Foundation
import PlaygroundSupport

var subscription: Cancellable? = Timer.publish(every: 1, on: .main, in: .common)
    .autoconnect()
    .print("data stream")
    .sink { output in
        print("finished stream with : \(output)")
    } receiveValue: { value in
        print("receive value: \(value)")
    }
    
RunLoop.main.schedule(after: .init(Date(timeIntervalSinceNow: 5))) {
    print(" - cancel subscription")
    // subscription.cancel()
    subscription = nil
}