block21.kt

// pseudocode
// marked by label
// ↓      ↓
label: whenStart
when (continuation.label) {
    0 -> {
        ...
    }

    1 -> {
        ...
        suspendReturn = noSuspendFriendList(user, continuation)
        if (suspendReturn == sFlag) {
            return suspendReturn
        } else {
            result = suspendReturn
            // Jump to the place marked by label
            // To execute the "when expression" again
            goto: whenStart
        }
    }

    2 -> {
        ...
    }

    3 -> {
        ...
    }
}