Do I need to explictly `close` a channel if I only want to `receive` a single value from it? Somethi...

# coroutines

[efemoney]

Do I need to explictly close a channel if I only want to receive a single value from it? Something like this inside some suspend function

val whatIWant = myChannel.receive()
myChannel.close()
return whatIWant

// VS

return mychannel.receive()

[Vivek Sharma]

I think no, but for if you want to be secure that, no more values should be send on the channel then yes

[marstran]

Are you sure using a Channel is the correct approach if you only want to receive a single value?

[efemoney]

Yeah @marstran, channel elements can be offered asynchronously via some callback

[Vivek Sharma]

if you want to receive a single value, we can use channel and then receive them as flow @marstran

[efemoney]

I have doubts if its needed to convert to flow. Whats the real difference between

myChannel.receiveAsFlow().first()
// AND
myChannel.receive()

[Vivek Sharma]

receiveAsFlow convert channel to hotflow, whenever something is send to channel, stateflow will be collecting values

[efemoney]

Yeah I know that. But specificallhy for the example above, what is the effect other than the unnecessary indirection via flow?

[Vivek Sharma]

you should check by trying I think, how both works

[marstran]

If all you need is to retrieve a value from a callback, you could just use suspendCancellableCoroutine to convert the callback-function to a normal suspend function.

[marstran]

See here: https://kotlin.github.io/kotlinx.coroutines/kotlinx-coroutines-core/kotlinx.coroutines/suspend-cancellable-coroutine.html

[marstran]

If the callback can be called multiple times, you can use callbackFlow instead.

[efemoney]

Yeah you are absolutely correct @marstran. I might not need a channel after all.