Running Side Effects

Without Error

val doThings: WIO[MyState, Nothing, MyState] =
  WIO
    .runIO[MyState](state => IO(MyEvent()))
    .handleEvent((state, event) => MyState(state.counter + 1))
    .autoNamed

Flowchart

BPMN

Model

{
  "meta" : {
    "name" : "Do Things",
    "error" : null
  },
  "_type" : "RunIO"
}

With Error

val doThingsWithError: WIO[MyState, MyError, MyState] =
  WIO
    .runIO[MyState](state => IO(MyEvent()))
    .handleEventWithError((state, event) =>
      if (true) MyState(state.counter + 1).asRight
      else MyError().asLeft,
    )
    .autoNamed

Flowchart

BPMN

Model

{
  "meta" : {
    "name" : "Do Things With Error",
    "error" : {
      "name" : "My Error"
    }
  },
  "_type" : "RunIO"
}

note

Errors render in flowchart only when they are handled