In this lesson we'll take a stateful React component and look at how we can refactor our <code>setState</code> calls to use an updater function and then leverage Ramda's <code>evolve</code>function to make our updater function a reusable utility that isn't tied to the React API.
![[React] Render Elements Outside the Current React Tree using Portals in React 16[圖]](data:image/gif;base64,R0lGODlhAQABAIAAAP///wAAACwAAAAAAQABAAACAkQBADs=)