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  margin: 0 auto
  max-width: 42em

  margin-left: .25em

  font-family: monospace
  padding: .25em .5em
  background: #e0e0e0
  border-radius: .25em


              const useState = React.useState;
const useCallback = React.useCallback;
const useRef = React.useRef;

const useDebounceCallback = (callback, delay = 500) => {
  const [val, setVal] = useState();
  const debounceTimer = useRef(null);
  const dispatch = useCallback((_val) => {
    clearTimeout( debounceTimer.current );
    debounceTimer.current = setTimeout(() => {
    }, delay);
  }, [callback, delay, debounceTimer]);
  return [val, dispatch];

function App() {
  const addTax = useCallback((val) => {
    return Math.round( val * 1.1 );
  }, []);
  const [val, setVal] = useState(0);
  const [dVal, setDVal] = useDebounceCallback(addTax, 1000);
  const onChange = useCallback((_val) => {
    const val = _val - 0;
  }, []);
  return (
      <h2>useDebounceCallback hook</h2>
      Set Value: 
        onChange={(e) => onChange(}
      <p>Actual value: {val}</p>
        Debounce value: {dVal}
        <br />
        <small className="code">value * 1.10</small>

ReactDOM.render(<App />, document.getElementById('root'));