I would like to express a suspend function as a callback: ```suspend fun getMyObject() : MyObject { ...

# getting-started

[Daniele B]

I would like to express a suspend function as a callback:

suspend fun getMyObject() : MyObject {
   ...
   return myObject
}

val myApp = myCallback { myObject ->
   /* code using myObject */
}

how should I write the function myCallback ?

[wbertan]

Hey, so what are you trying to achieve? as I notice you want to execute the block but also return a value for myApp?
For example (Using String as the MyObject):

suspend fun getMyObject(): String {
        return "something"
    }

    suspend fun myCallback(block: suspend (String) -> String): String {
        return block(getMyObject())
    }

    val myApp = myCallback { myObject ->
        myObject
    }

This makes your block responsible to return the value to assign to myApp.
If you want directly the value from getMyObject but ALSO execute the block with the value, can be something like this:

suspend fun myCallback(block: suspend (String) -> Unit): String {
        return getMyObject().also { block(it) }
    }

    val myApp = myCallback { myObject ->
        // do something with myObject
    }

[Daniele B]

that’s great!!! thanks
I wasn’t actually focused on myCallback returning a value

[Daniele B]

Note: DKMPViewModel.getWebInstance() is a suspend function

[Daniele B]

Actually I couldn’t make it work.
The error is:

Suspend function 'myComposeApp' should be called only from a coroutine or another suspend function

[streetsofboston]

Start your main with runBlocking { ...} or declare your suspend fun main() as suspend.

[CLOVIS]

Don't spam multiple channels.

[Daniele B]

Sorry, I had just posted a message in #coroutines, but somehow this channel is always the most helpful