---
tags: rxjs, case_study
---
# Case Study: Pass valur to few steps later

    const createAll$ = forkJoin(xxxObsArr).pipe(
      switchMap((xxxArr) => {
        const getYYY$ = forkJoin(yyyObsArr).pipe(
          map((yyyArr) =>
            yyyArr.map((yyy) => ({
              ...yyy,
              newOne: xxxArr.find((xxx) => xxx.name === yyy.name).newOne,
            }))
          )
        );

        return getYYY$;
      }),
      switchMap(...)
    );