Can I mark my methods as blocking to opt-in to the "inappropriate blocking call" warning somehow?

# coroutines

[spand]

Can I mark my methods as blocking to opt-in to the "inappropriate blocking call" warning somehow?

[Big Chungus]

Why can't you just dispatch them on Dispatchers.IO?

[spand]

That would be step 2

[spand]

Also, I cannot get rid of them so to prevent further accidental blocking calls in suspending functionss

[Big Chungus]

No I mean Dispatchers.IO are meant for blocking calls

[Big Chungus]

So

suspend fun myFun() {
  someSuspendFun()
  launch(<http://Dispatchers.IO|Dispatchers.IO>) { someBlockingFun() }
}

[spand]

Yes I am well aware. I want a warning when I or someone else forgets to do it

[Big Chungus]

Oooh, i totally misunderstood you issue. Apologies. 😀

[Big Chungus]

You can add RequiresOptIn annotation

[Big Chungus]

Or create a custom annotation like this https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-experimental-stdlib-api/

[louiscad]

You can add @Throws(IOException::class) I think, it should be an okayish workaround.

@elizarov Do you think declaring potentially long blocking functions could land in Kotlin at some point?

I'd use a way to declare if a function does significant CPU work or blocking I/O. Such a thing could propagate similarly to @RequiresOptIn annotated annotations (with warning or error), until stopped manually or automatically at the relevant dispatcher switch (using the invoke operator, withContext or explicit dispatcher injection e.g. in a launch call).

[CLOVIS]

Is there a way to tell the IDE to not display that warning inside a withContext(IO)?

[spand]

It happens by default

[spand]

Unless you are talking about the @RequiesOptIn way

[CLOVIS]

Not for me... I have to tell IntelliJ to ignore all calls one by one, it's really not fun

[spand]

You should report it. I had a similar bug that was fixed very fast.