Read value from Kotlin flow and return immediately - kotlin

Question

I have to read a value from a flow just once and then immediately return it from the function. I have a piece of code like this:
fun getValue(): String {
val flow = getFlow()
Mainscope().launch {
flow.collect {
return it
}
}
}
But this is giving me an error saying that I cant return from inside collect. I know that ideally I should be returning the flow object itself and then calling collect on the returned flow. But it is not possible, since getValue() has already been used in several places by now and I cannot change its signature now.
I have tried using suspend and synchronized as follows:
// call the function like this: runBlocking { print(getValue()) }
suspend fun getValue(): String {
val flow = getFlow()
flow.collect {
return it
}
}
and
fun getValue(): String {
val lock = Any()
var value: String? = null
val flow = getFlow()
MainScope().launch {
flow.collect {
synchronized(lock) {
value = it.toString()
lock.notify()
}
}
}
synchronized(lock) {
while (value == null) lock.wait()
return value as String
}
}
But in both cases the control never reaches inside collect. So I tried putting collect inside a new thread:
...
val flow = getFlow()
thread {
MainScope().launch {
flow.collect {
synchronized(lock) {
value = it.toString()
lock.notify()
}
}
}
}
synchronized(lock) {
...
but its still the same. So how do I read the value from the flow in a non-suspending way and return it immediately?

Answer 1

To get first value of the flow:
fun getFlow() = flowOf("one","two","three")
fun getValue(): String {
var r = ""
runBlocking {
r = getFlow().firstOrNull()?:"none"
}
return r
}
println(getValue())
//one
To get last value of the flow:
fun getValue(): String {
var r = ""
runBlocking {
getFlow().collect {
r = it
}
}
return r
}
println(getValue())
//three