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CleanShot 2024-07-14 at 14.42.33@2x.png

CleanShot 2024-07-14 at 14.42.44@2x.png

First photo,  this is how I usually do stuff
Second photo, I didn't know I could do this. I am confused why use onEach though. I thought all of the "on*" operators were side-effecty

*Edit:*
Just read the above question. My question is sorta similar it seems. lol

It depends on your use case, but I always prefer manually launching versus using `launchIn`.

```launch {
  flow.collect { item -&gt; ... }
}```

> I am confused why use onEach though
• `flow.onEach { doStuff(it) }.collect()` is equivalent to `flow.collect { doStuff(it) }`
• `flow.launchIn(scope)` is equivalent to `scope.launch { flow.collect() }`
So... if you want to use `launchIn`, you kind of have to go with `onEach`, because you don't control the `collect()` call anymore (you can't pass a lambda to it). I do tend to prefer `scope.launch { flow.collect { ... } }` in general, but I don't have a very strong opinion on this, I guess it's a matter of style.

> I thought all of the "on*" operators were side-effecty
Well `updateUI(event)` seems quite side-effecty to me :smile: It does seem to match what you expected here

`updateUI` is the direct effect, not a side effect

Ah I see. I was thinking in terms of something that changes state, as opposed to a pure function

One benefit of launchIn is it prevents you from mistakenly collecting without launching a separate coroutine, which would suspend the main coroutine.

<https://www.billjings.com/posts/title/avoid-launchin/?up=|https://www.billjings.com/posts/title/avoid-launchin/?up=>