Typing hooks

// useState that has nullable object with arbitrary value type
const [data, setData] = useState<Record<string, unknown> | null>(null);

// setState
setState: React.Dispatch<React.SetStateAction<number>>;

// useCallback
const renderBlockList: () => Array<ReactElement> = useCallback(
  () => [
      <div>
        {...}
      </div>
    ], [some_dependency]
);

// useMemo
const randomValuesArray = useMemo<Uint16Array>(() => new Uint16Array(22), []);