Hello, so I am wondering about this piece of code ...

# coroutines

[oday]

Hello, so I am wondering about this piece of code

private fun startCoroutines() {
    GlobalScope.launch(Dispatchers.Main) {
        withTimeout(1000L) {
            println("This is executed before the first delay")
            stallForTime()
            println("This is executed after the first delay")
        }

        printAfterSomething("the timeout")
    }

    println("This is executed immediately")
}

suspend fun stallForTime() {
    withContext(Dispatchers.Default) {
        delay(2000L)
    }
}

after the child job inside withTimeout does not finish in time (because stallForTime made it take too long (2 seconds))

why does the printAfterSomething not get called

[oday]

or otherwise, why does the parent seemingly also get canceled? the child didnt crash or anything, nor did I call cancel, why am I not seeing the printAfterSomething print statement?

[oday]

ok sorry got it, cause withTimeout throws an exception, and if exception is thrown inside the child, parent cancels as well

[jw]

Yes, but note that there's no parent/child here. There's just one coroutine that's moving around between dispatchers and through functions.

[oday]

ok then I dont know what makes a job a child of another, which caused me to face another problem with another example here if you have the time to look

https://klassbook.commonsware.com/lessons/Coroutine%20Basics/cancel-sans-cooperation.html

so line 24 here, this cancels that job right? Ok

this example is showing how that busyWait and print dont honor cancellation request

[oday]

yea i dont even know what the question is, I dont understand what is going on there and how to make the job wait for cancellation and not print the subsequent lines….i tried to call join on that job or cancelAndJoin but I am not even sure what join does….

[oday]

ignore the above, sorry about that, it’s of course cancelAndJoin so it could wait until cancelation is done and NOT print them

[oday]

@jw you still hit IRC somewhere? or all Slack now?

[jw]

Not in many years