What is the correct way of catching an exception i...

# coroutines

[CLOVIS]

What is the correct way of catching an exception in Flow.flatMapMerge?

I have this:

val f: Flow<CustomObject> = ...
f.flatMapMerge {
  it.customFlow()
}

This works fine as long as there is no exception, however if there is one, the entire flow is cancelled. I tried to write

f.flatMapMerge {
  try {
    it.customFlow()
  } catch(e: Throwable) {
    println("Caught")
    emptyFlow()

}
}

but that still cancels the flow, instead of just skipping items for which the conversion fails.

[CLOVIS]

Oh, that's because the exception is only thrown during collection.

But if I add a .catch after the .flatMapMerge, the flow has still been cancelled.

[Zach Klippenstein (he/him) [MOD]]

Use the catch operator on the inner flow (customFlow)

[CLOVIS]

Thanks! Not sure how I missed that 😓