Make mandatory to pass initial state in React.useState

Right now, it is possible to use hooks in order to set state for functional components as follows:

function Foo() {
  const [state, setState] = React.useState();
}

There is no parameter passed to useState above. If it is blank, React assumes it is undefined. I think it would be an improvement to make it compulsory to pass a parameter to useState. If it is supposed to be undefined, one should pass undefined. Or at least, there should be a warning if one does not manually set initial state.

This will make the developers be aware of what initial state they have set. And also the blunders like const [state = initial, setState] = React.useState().

Proposed way of doing

function Foo() {
  const [state, setState] = React.useState(initial);
}

[acagastya]

@TodorTotev if it is not explicitly stated, it is taken as undefined. Developers can manually set undefined. But it would be a breaking change. Other than that, I don’t see a reason why that should be a problem – But I welcome the opportunity to learn why you think otherwise.

But at the very least, warnings will be helpful.

[stale[bot]]

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