Do I understand correctly that there are no ways t...

# coroutines

[r4zzz4k]

Do I understand correctly that there are no ways to have observable collection out of the box? So if I want observable list, I have to have either a channel holding either new copy of the list or incremental changes depending on the use-case?

[elizarov]

I would not recommend combining observability and concurrency. Observable frameworks better be confined to UI thread.

[r4zzz4k]

I'm actually not having UI in mind, I'm thinking about decoupling of business logic from input events. Right now I have a chain of producers which gets byte buffer from some place (static test data, will later be provided by hardware I/O, doesn't matter for the question though), parses them into well-known commands (described as sealed class) and then updates data layer consisting of several classes with `BroadcastChannel`s. Now I'm working on the logic itself which should act on these classes, and that's where the question regarding collection arises -- there is a collection of entities which can change over the lifetime, and I want to react to these changes.

Thinking about it a bit more -- every entity has unique tag, so it's probably just a matter of an additional sealed class with Added(tag, value), Removed(tag) and changes to the entities themselves should be covered by their own channels.

Or am I missing something?

[r4zzz4k]

Sorry for quite cumbersome description, I still don't have bird's-eye view on what I'm implementing in mind.

[elizarov]

We don't have an out-of-the-box abstraction readily available, but there was somewhat similar use-case that is recorded here: https://github.com/Kotlin/kotlinx.coroutines/issues/145

[r4zzz4k]

Yes, looks similar to what I'm looking for, probably with an added notification when new entity is added or removed. Thank you for the link.
I should probably investigate if similar problem is solved in some actor framework or coroutine / channel implementation.