pmndrs/jotai v2.2.0

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// suppose we have this
const asyncAtom = atom(() => Promise.resolve(1))
const countAtom = atomWithDefault((get) => get(asyncAtom))
// and in component
const setCount = useSetAtom(countAtom)

// previously,
setCount((c) => c + 1) // it worked, but it will no longer work

// instead, you need to do this
setCount((countPromise) => countPromise.then((c) => c + 1))

// suppose we have async storage
const storage = createJSONStorage(() => AsyncStorage)
const countAtom = atomWithStorage('count-key', 0, storage)
  // in component
  const [count, setCount] = useAtom(countAom)

  // previously, countAtom is a sync atom, so you could update like this:
  setCount((c) => c + 1)

  // with the new version, it becomes async occasionally, so you need to resolve it:
  setCount(async (c) => (await c) + 1)