complex-right.ts

fromEvent(document.querySelector('input'), 'input').pipe(
  debounceTime(300),
  map(event => (event.target as HTMLInputElement).value),
  switchMap(query => getData(query).pipe(
    switchAll(),
    map(({firstName, lastName}) => firstName + ' ' + lastName),
    toArray(),
  )),
).subscribe(console.log);