val state = MutableStateFlow(...)

state.map {
  // a reducer
}.catch {
  // catch the exception happened in a reducer
}

reduce { 
   // omitted
}.catch {
   when (exception) {
     // to distinguish between stateA & stateB exception, unless it's a general toast
     ExceptionFromStateA -> state.copy(a = // do something with data specific to stateA)
     ExceptionFromStateB -> state.copy(b = // similar to the above apprach)
   }

   // or a general error message
   state.copy(errorMessage = it.message)
}

runCatching

.catch

will update the github link, still AFK 🙏

intent { }

fun loadDataForId(id: Int) = intent {
   postSideEffect(MySideEffect.Toast("Loading..."))
   
   val result = try {
       repository.loadData(id)
   } catch (e: NetworkException) {
       postSideEffect(MySideEffect.Toast(e.code().humanizedMessage()))
       null
   }

   reduce {
       state.copy(data = result)
   }
}

private fun Int.humanizedMessage() = when (this) {
   404 -> "Ooops, There's no such resources exist"
   400 -> "Ooops, we can't process those data"
   // ... any other http error code here
   else -> "OOops, something went wrong"
}