Say i have a Composable which, makes use of `stringResource` and maps from one object to another. I...

# compose

[ritesh]

Say i have a Composable which, makes use of stringResource and maps from one object to another. I should be marking it as @ReadOnlyComposable ?
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[ritesh]

@Composable
@ReadOnlyComposable
fun SomeSealedClass.toOtherSealedClass(): OtherSealedClass {
  return when (this) {
    is SomeSealedClass.Something -> OtherSealedClass.Something(label = stringResource(id = this.stringId))
  }
}

[ritesh]

Since this composable will never write to the composition, it can be marked as ReadOnlyComposable IMO, to avoid generating groups and all.

[takahirom]

As I recall, a Composable that returns a value should not have a group.

Functions that have a non-unit return value don’t get their own scopes because they can’t be re-executed without also re-executing their caller, so their caller can “see” the new return value computed by the function.

https://dev.to/zachklipp/scoped-recomposition-jetpack-compose-what-happens-when-state-changes-l78

[Zach Klippenstein (he/him) [MOD]]

You never need to use these sorts of annotations. But yea if a composable returns a value then I don’t think this particular annotation has any effect anyway.

[ritesh]

Ahh okay, but it will make compose runtime avoid generating groups and all on slot table? As it's not writing to a composition, generating things like those can be avoided, i believe.