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kotlinlang

Given a `StateFlow&lt;T&gt;` instance, I want to log every emission of `T` from the source standpoint. Is this possible without duplicating logs for each subscriber?

We currently log at this point (before converting into a state flow):

```.scan { .. }
.logEachState(logger)
.stateIn(scope)```
But this will log duplicate values that are not emitted to subscribers.

We had a bug where `T` was not immutable and was not emitting when it’s `var` changed bc only the instance was mutated - (same instance will not be emitted twice in a row due to equality checks, even if the value changes)

if we logged at each subscriber, then we risk some real noisy logs 

If I understand correctly, you basically want to swap line 2 and 3?

Yep, but it's a `doOnNext()` which returns a `Flow&lt;T&gt;` - and I want a `StateFlow&lt;T&gt;`

```.scan { .. }
.stateIn(scope)
.apply { logEachState(logger).launchIn(scope) }```

Oh wait, I'm guessing you don't want to log when there are no subscribers. If that's the case my code snippet won't work.

You could add a `distinctUntilChanged()` to your snippet I guess.

I guess you need something like this: <https://kotlinlang.slack.com/archives/C1CFAFJSK/p1652287040843249>

but for `onEach`

Reworked - &lt;duh&gt;
Expose your State flow like
// expose as
val state = flow { ...}
.stateIn(scope)
// Log with
private loggy = state.onEach {
   log(it)
}.launchIn(..)