This lambda with receiver stuff in the kotlinx coroutines API is playing with fire.

# coroutines

[groostav]

This lambda with receiver stuff in the kotlinx coroutines API is playing with fire.

[Dico]

I would think they return the same exact thing in those suspend functions? The scope receiver and the continuation passed to the top level coroutineContext property at runtime typically are implemented by the same class and thus the same reference.

[groostav]

when you create an instance of a suspend () -> Unit, needless to say its coroutineContext can be greatly varied. Thus:

public fun myThing() = runBlocking {
  val x: suspend () -> Unit = { 
    val context = coroutineContext //did you get the invoker of X's context or did you get the runBlocking's context?
  }
}

[groostav]

the answer btw is the runblocking's context, which suprised me, its also difficult because I believe there is no way I can add a label to the anonymous function syntax I'm using

[Dico]

That's a sad oversight...

[groostav]

I think it might be worthy of a PR, something like currentCoroutineContext or runningCoroutineContext

[groostav]

leave the old one as an alias, but it was inline-intrinsic anyways, so I think that means its name can be changed relatively easily

[Dico]

I know it would be the runblockings context... that means you cant access the other one easily. You can create your own function to get what you want:

suspend inline fun getCoroutineContext() = suspendCoroutineUninterceptedOrReturn { cont -> cont.context }

[Dico]

But yeah, it should be named better

[Dico]

Probably want to make that inline

[groostav]

I was using suspendCoroutine { it.resume(it.context) } but yeah, even more simply I can create another inline global static function just to alias coroutineContext to something else.

[groostav]

inline suspend fun currentCoroutineContext() = coroutineContext

[Dico]

Of course haha

[Dico]

It would be cool if suspend val became a thing

[groostav]

created https://youtrack.jetbrains.com/issue/KT-33106?project=kt

[groostav]

Im really not sure about suspend val. When exactly is something too big to be a property? I donno, I've done a great deal of hand-wringing about suspend val.

[bdawg.io]

Methods on a receiver scope win over global methods with the same name unless you fully qualify the method name

[bdawg.io]

Is there a reason your lambda is being defined inside of that function instead of simply suspend fun x() { val context = coroutineContext } above the myThing function?

[Dico]

I have a good use case for it but it's elaborate to explain