val context = Executors.newFixedThreadPool(Runtime.getRuntime().availableProcessors()).asCoroutineDispatcher()
fun main() {
    val foo = Foo()
    val foo2 = Foo()

    thread { while (true) foo.spawn() }
    thread { while (true) foo2.spawn() }

    Thread.sleep(5000)
    foo2.close()
}

class Foo {
    private val instanceScope = CoroutineScope(context)
    private var bar = Bar(instanceScope)
    fun spawn() {
        runBlocking {
            val streamer = bar.streamer()
            for (x in streamer) {
                println("${Thread.currentThread().name} got a $x")
            }
        }
    }

    fun close() = instanceScope.cancel()
}

class Bar(scope: CoroutineScope) : CoroutineScope by scope {
    var num = Random.nextInt(10000)
    var invocations = 0
    fun streamer() = produce {
        invocations++
        repeat(5) {
            delay(500)
            send("$invocations-${num++}")
        }
    }
}