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If you are calling an api and stored data in useState. sometimes you may get an error called 'undefined' when you use map in your jsx.
ex: const [responseData, setResposeData] = useState();
axios.get('http://url').then(resp => {
setResposeData(resp)
});
responseData.map((item)=>
//your code
)
then add ? it works like a try and catch block and avoids undefined errors.
responseData?.map((item)=>
//your htlml code
)
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