// Available variables:
  // - Machine
  // - interpret
  // - assign
  // - send
  // - sendParent
  // - spawn
  // - raise
  // - actions
  // - XState (all XState exports)
  
  const machine = Machine({
    initial: 'loading',
    context: {
      value: 0
    },
    invoke: {
      src: 'onload',
      onError: {
        target: 'error',
        internal: true,
        actions: assign((context, event) => ({...context, error: event.data}))
      }
    },
    on: {
      loaded: {
        target: 'loaded',
        internal: true,
        actions: assign((context) => ({value: context.value + 1}))
      }
    },
    states: {
      loading: {},
      loaded: {},
      error: {}
    }
  }, {
    services: {
      onload: () => (fireEvent) => {
        throw new Error("An error");
      }
    }
  });
  
  const service = interpret(machine);
  service.start();