1st implementation of launch (failed)

KotlinCoroutineLaunchTest.kt

package learningtest

import kotlin.coroutines.*

private class MyCont<T>(override val context: CoroutineContext): Continuation<T> {
    override fun resumeWith(result: Result<T>) {
        println("Resume with: ${result}")
    }
}

fun <T> CoroutineContext.launch(block: suspend CoroutineContext.()->T) =
    block.startCoroutine(this, MyCont(this))

suspend fun test(msg: String, a:Int): Int {
    println("$msg - 1")
    delay(10)
    println("$msg - 2")
    delay(10)
    println("$msg - 3")
    return a * 2
}

suspend fun delay(t: Int) {
    val start = System.currentTimeMillis()
    var i = 0
    while(true) {
        val now = System.currentTimeMillis()
        i++
        if(i%10_000_000 == 0) println("busy waiting: ${"%,d".format(i)}")
        if(now - start >= t) return
    }
}

fun main() {
    fun t() = java.time.LocalTime.now()
    println("start ${t()}")
    EmptyCoroutineContext.launch {
        launch {
            println("${test("1st", 30)}")
            println("after 1st launch ${t()}")
        }
        launch {
            println("${test("2nd", 30)}")
            println("after 2nd launch ${t()}")
        }
    }
    println("after launch ${t()}")
    Thread.sleep(4000)
}

실행 결과:

start 11:00:02.266474
1st - 1
1st - 2
1st - 3
60
after 1st launch 11:00:02.300051600
Resume with: Success(kotlin.Unit)
2nd - 1
2nd - 2
2nd - 3
60
after 2nd launch 11:00:02.320648200
Resume with: Success(kotlin.Unit)
Resume with: Success(kotlin.Unit)
after launch 11:00:02.320648200

실패함!