Implement fizzbuzz with actor of kotlin coroutine.

actor_fizzbuzz.kt

class Value(val value: Int, var output: String = "")

fun rule(seed: Int, print: String, next: SendChannel<Value>) = actor<Value> {
    for (value in channel) {
        next.send(value.apply {
            if (value.value % seed == 0) {
                this.output += print
            }
        })
    }
}

fun printer() = actor<Value> {
    for (value in channel) {
        if (value.output.isNotEmpty()) {
            println(value.output)
        } else {
            println(value.value)
        }
    }
}

fun fizz(next: SendChannel<Value>) = rule(3, "Fizz", next)

fun buzz(next: SendChannel<Value>) = rule(5, "Buzz", next)

sample.kt

fun main(args: Array<String>) = runBlocking<Unit> {
    val fizzBuzz = fizz(buzz(printer()))
    repeat(100) {
        fizzBuzz.send(Value(it + 1))
    }
}