In this example of actors from the guide. What ens...

# coroutines

[spand]

In this example of actors from the guide. What ensures the memory safety of the counter variable ? ie. that the latest write to counter is always read by the next processing thread?

fun counterActor() = actor<CounterMsg> {
    var counter = 0 // actor state
    for (msg in channel) { // iterate over incoming messages
        when (msg) {
            is IncCounter -> counter++
            is GetCounter -> msg.response.complete(counter)
        }
    }
}

[spand]

Is it the read from the mailbox that ensures the proper happens before relation?

[louiscad]

The for loop is executed sequentially, so no concurrency inside it

[spand]

I know, but that does not mean its memory safe. I pretty sure there has to be a read barrier somewhere and there probably is but I would prefer to see it documented.

[Evgeniy Zaharov]

look at this article: https://proandroiddev.com/what-is-concurrent-access-to-mutable-state-f386e5cb8292

[spand]

Thanks. That answers it all 🙂