typing problem storeApi outside of react with immer middleware

@kurosh-z Hey, I fixed it recently. Please check the example in #169. If it doesn’t work, would you please file a new issue?

_Originally posted by @dai-shi in https://github.com/react-spring/zustand/issues/75#issuecomment-684075606_

Hi , #169 actually solved the typing problem inside of react. But if you use the setState api outside of react, typescript requires you to return the state.

// outside of react
useStore.setState((state) => {
  state.bb.b1 = true;
});

codeSandbox :

https://codesandbox.io/s/pedantic-flower-immerzustand-forked-ptso7?file=/src/App.tsx

[dai-shi]

Let me close this issue as the first question is answered and now the context is a bit changed.

I added the above immer snippet in readme.md.

[dai-shi]

Ah, the codesandbox example in my comment. Here’s the fixed version: https://codesandbox.io/s/pedantic-flower-immerzustand-forked-5zdy9

The immer middleware with types:

const immer = <T extends State>(
  config: StateCreator<T, (fn: (state: T) => void) => void>
): StateCreator<T> => (set, get, api) =>
  config((fn) => set(produce(fn) as (state: T) => T), get, api);

Very weird the you need to extend it

It’s a long story (also discussed in various TS issues), but that’s how it works.