Hey friends, is it reasonable to run suspended fun...

# arrow

[Hugo]

Hey friends, is it reasonable to run suspended functions within an IO? We're migrating from IO to suspend and wondering about interoperability. E.g. in this example, myFun() works as expected, despite log(..) being a suspended function. I believe this is because IO now uses suspend under the hood?

import <http://arrow.fx.IO|arrow.fx.IO>
import kotlinx.coroutines.delay

suspend fun log(message: String) {
  delay(1000)
  println(message)
}

fun myFun(): IO<Unit> = IO {
  log("test")
}

myFun() // does nothing, suspended
myFun().unsafeRunSync() // logs "test"

[raulraja]

Hi @Hugo,
IO was in a way doble wrapping suspend. You can use IO in 0.12 alongside suspend as in your example but be aware that in 0.13 IO is gone.
In your example translated to suspend you would push all of it’s running until the edge with suspend fun main or integrating with an endpoint that takes suspend or in Android in whatever compose handlers etc. Other than that suspend already covers all the use cases of IO. https://www.47deg.com/blog/arrow-0.13.0-release/
https://arrow-kt.io/docs/effects/io/

[Hugo]

Thanks @raulraja! Sounds like we're on the right track then 👍

[raulraja]

Glad to hear, if you run into any issues migrating feel free to ping us 🙂