Uncaught TypeError: Cannot read properties of undefined (reading '0') at line 13:1

while working on code ran into some errors on line 13 when the value is undefined and is reading as 0 please how can I solve this

the error message

homepage.js:13 Uncaught TypeError: Cannot read properties of undefined (reading ‘0’)

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  const dispatch = useDispatch();
  const danceClass = useSelector((state) => state.class);
  const { classes } = danceClass;

  const [dance, setDance] = useState(
    classes[0] ? classes[0].slice(0, 3) : [],
  );

>Solution :

Because the classes is undefined. You should check like

classes ? classes[0]?.slice(0,3) : []