@Effect()
  loadData$: Observable<Action> = this.actions$
    .ofType(ActionTypes.LOAD_DATA)
    .pluck('payload')
    .switchMap(params => {
      return this.myService.getData(params)
        .map(res => new LoadDataCompleteAction(res))

        // ...and this part would have to be extracted:
        .retryWhen(attempts => Observable
          .zip(attempts, Observable.range(1, 5))
          .flatMap((n, i) => {
            if (i < 4) {
              return Observable.timer(1000 * i);
            } else {
              throw(n);
            }
          })
        )
    })
    .catch(err => Observable.of(new LoadDataFailed()));

@Effect()
  loadData$: Observable<Action> = this.actions$
    .ofType(ActionTypes.LOAD_DATA)
    .pluck('payload')
    .switchMap(params => {
      return this.myService.getData(params)
        .map(res => new LoadDataCompleteAction(res))
        .retryWhen(attempts => Observable.retryOrThrow(attempts, maxAttempts)

         // or maybe - that's my design question
         .retryOrThrow(attempts, maxAttempts)
    })
    .catch(err => Observable.of(new LoadDataFailed()));

declare module 'rxjs/Observable' {
  interface Observable<T> {
    retryOrThrow<T>(): Observable<T>;
  }
}

Observable.prototype.retryOrThrow = function(attempt, max) {
  console.log('retryOrThrow called');

  return Observable.create(subscriber => {
    const source = this;
    const subscription = source.subscribe(() => {
        // important: catch errors from user-provided callbacks
        try {
          subscriber
            .zip(attempt, Observable.range(1, max + 1))
            .flatMap((n, i) => {
              console.log(n, i);
              if (i < max) {
                return Observable.timer(1000 * i);
              } else {
                throw(n);
              }
            });
        } catch (err) {
          subscriber.error(err);
        }
      },
      // be sure to handle errors and completions as appropriate and send them along
      err => subscriber.error(err),
      () => subscriber.complete());

    // to return now
    return subscription;
  });
};