Feature request: api.subscribe(callback, /*selector*/) about zustand HOT 5 CLOSED

This is great! It would be good to test the performance when React is not in development mode. I was seeing comparable speeds with the production version of React.

But this is definitely worth exploring. I was just prototyping something that involved updating the store without calling React's dispatch (not performance related). It seems like we should enable full features for reading and writing state outside of React. We might need to make some of the types less strict. I'll look into this today.

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It's difficult to define the function signature of StateListener. Apparently generics are inferred as {} if used before being assigned a type. StateSelector is the second argument so the generic U is not inferred yet when the StateListener type is defined. I was able to get it to work by reversing the parameter order: subscribe(selector | listener, listener) but I don't like it.

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you mean i could either do

sub(state => console.log("state changed"))

or

sub(state => state.x, x => console.log("x has changed"))

?

I would actually prefer this : D but probably only because i don't know TS good enough to see the downsides (?)

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Yes, you would be able to do that. The selector function is optional and I'm used to optional parameters being last. Haha I guess it's mostly preference though. If you like it, I'm fine with it.

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Wound you merge it? I think this functionality would make it very versatile.

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