React- is useState synchronous (not the setter returned by useState but useState itself)?

Question

const Child = (props) =>
{
    const {data1, data2} = props;
    let defaultData = [];
    //do some logic based on data1 and data2 e.g.
    defaultData.push(data1 + data2); 
    const [myStateData, myStateDataSetter] = useState(defaultData);
    console.log(myStateData);
}

Will myStateData always be defined? (I understand that myStateDataSetter(newData) is async - that is not my question; I am asking if the first assignment using the default param to useState is synchronous).

https://stackoverflow.com/questions/54119678/is-usestate-synchronous You can check that link — mc-user, Apr 07 '22 at 16:13

score 1 · Accepted Answer · answered Apr 07 '22 at 16:14

1

Yes it is. Given

const [someState, setSomeState] = useState(initialValue);

When the component mounts, someState will always be initialValue - it won't be undefined or anything else that requires a re-render before the state gets initially populated.

answered Apr 07 '22 at 16:14

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React- is useState synchronous (not the setter returned by useState but useState itself)?

1 Answers1