Does anyone have any solutions for returning a res...

# coroutines

[Jonathan]

Does anyone have any solutions for returning a result to a Channel sender? I'm using a rendezvous Channel too synchronously send data to consumer coroutine that writes to a output stream. I would like to be able to return a boolean value indicating the result of the write to the coroutine that handles sending the work to the rendezvous Channel.

[Joffrey]

I don't understand your setup. Since there is no buffering, why not perform the write to the output stream directly from the same coroutine?

[Jonathan]

The way my code is written, I have a dedicated coroutine that accepts my OutputStream as an argument and will loop indefinitely writing data when it arrives in the Channel. I opted to use a channel so that I could eliminate the need for null checks on the stream, since my coroutine received a non-null instance.... I also thought it was best to use a channel to safely communicate between two coroutines... With that being said I'm not entirely sure I need to have a dedicated output coroutine.

[jw]

Send a callback

[jw]

Send a completable deferred

[Youssef Shoaib [MOD]]

A technique in concurrent programming is to send a reply channel that you want the person to reply on. Sending a completable deferred is definitely the better way since it enforces a single reply!

[Joffrey]

So yeah, we can replace the return channel with a deferred, and then go one step further and replace the send channel with a suspend call. No need for a channel or multiple coroutines at all in this case.

[Joffrey]

It would only be useful if there was a buffer, but we're talking about a rendezvous channel here.

[Jonathan]

Is the deferred necessary if I use a suspend function instead? The function could return a value indicating the result.

[Jonathan]

Also, what's the intended use case of a rendezvous Channel if it shouldn't be used as a mechanism for communicating between two Coroutines?

[jw]

It's unidirectional, you wanted bidirectional

[Jonathan]

Ah, I see. If I didn't want to signal success to sender, it would be fine to use..👌🏿

[Joffrey]

Also, I didn't say it shouldn't be used as a mechanism to communicate between coroutines. I'm saying you probably don't need 2 coroutines in the first place in your case, which simplifies the problem of 2-way communication because it removes the need for a channel in the first place