useState-as-a-ref

useState-as-a-ref.jsx

const [node, setRef] = useState(null);

useEffect(() => {
  if (!node) {
    console.log('unmounted!');
    return null;
  }
  
  console.log('mounted');
  
  const fn = e => console.log(e);
  
  node.addEventListener('mousedown', fn);
  return () => node.removeEventListener('mousedown', fn);
}, [node])

// <div ref={setRef}....