Promise and async/await sample in Kotlin/JS

coroutineSample.kt

fun main(args: Array<String>) {
    launch {
        loadAllFiles()
    }
}

fun launch(block: suspend () -> Unit) {
    block.startCoroutine(object : Continuation<Unit> {
        override val context: CoroutineContext get() = EmptyCoroutineContext
        override fun resume(value: Unit) {}
        override fun resumeWithException(e: Throwable) { println("Coroutine failed: $e") }
    })
}

suspend fun <T> Promise<T>.await(): T = suspendCoroutine { cont ->
    then({ cont.resume(it) }, { cont.resumeWithException(it) })
}

suspend fun loadAllFiles() {
    println("step1!")
    openFile("https://yesno.wtf/api").await()
    println("step2!")
    openFile("https://yesno.wtf/api").await()
    println("step2!")
    openFile("https://yesno.wtf/api").await()
    println("done!")
}

fun openFile(url: String): Promise<XMLHttpRequest> {
    val p = Promise<XMLHttpRequest> {
        resolve, reject ->
        val xhr = XMLHttpRequest()
        xhr.open("GET", url)
        xhr.addEventListener("load", {
            e ->
            resolve(xhr)
        })
        xhr.send()
    }
    return p
}

// References:
//   https://discuss.kotlinlang.org/t/async-await-on-the-client-javascript/2412
//   https://sbfl.net/blog/2016/07/13/simplifying-async-code-with-promise-and-async-await/

Do you know how we can accomplish the same using the new 1.3 coroutines instead of the experimental coroutines? Thanks!