hello guys, I am fighting with intellij and coroutines. I try to use `produce` I have imported it fr...

# coroutines

[Tamas]

hello guys, I am fighting with intellij and coroutines. I try to use produce I have imported it from import kotlinx.coroutines.channels.produce but the ide still displays it red, and says create function on alt-enter. my dependencies are

implementation 'org.jetbrains.kotlin:kotlin-stdlib-jdk8'
    implementation 'org.jetbrains.kotlinx:kotlinx-coroutines-jdk9:1.3.7'
    implementation 'org.jetbrains.kotlinx:kotlinx-coroutines-javafx:1.3.7'

[octylFractal]

is kotlinx-coroutines-jdk9 a thing? I thought there was only jdk8

[Tamas]

https://search.maven.org/artifact/org.jetbrains.kotlinx/kotlinx-coroutines-jdk9/1.3.7/jar

[octylFractal]

Additionally, you may need an explicit dependency on kotlinx-coroutines-core, I don't know if the other ones declare it as api or implementation, the latter would mean core wouldn't appear on your classpath

[Tamas]

I will try this

[araqnid]

(the jdk9 flavour added interop with Java9's Flow, a reactive streams implementation)

[octylFractal]

yes, I see that now

[Tamas]

did not change

[Tamas]

fun addFile(file: File): ReceiveChannel<List<String>> = produce {
    }

[Tamas]

the ide writes unresolved reference, but with ctrl+click I can jump to produce sources

[octylFractal]

oh, I know why that's unresolved -- you don't have a CoroutineScope to call it on

[octylFractal]

unless that's not part of the snippet you showed

[Tamas]

hmm that is it

[Tamas]

I was watching a tutorial online - and that one does not use CoroutineScope. it is version m6 of coroutines though

[octylFractal]

yes, the scoping / structured concurrency was added in the later iterations of coroutines

[Tamas]

then this leads to my next question. the examples on the kotlin site are for functions, but I would like to use produce in a method of a class. how can I get the coroutine scope there

[octylFractal]

pass it as a normal argument, either to the method or the constructor

[octylFractal]

receivers are just syntax sugar 🙂

[Tamas]

thanks for your help! I will try further 🙂 (it is harder to wrap my head around it than I first thought)