Equivalent of `getState()` from redux.js about reducer HOT 6 CLOSED

I've put this fix to good use (copying the state when I need it rather than on every update). Thanks for taking the time to explain, and for addressing this request.

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Sorry, just realized I used Subscription without any context. I got that from redux-rs, it's the function signature that takes a reference to the State.

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The reason why Store doesn't provide direct access to the inner state at the moment, is because I felt it would encourage anti-patterns that deviate from a truly reactive design, but I'd love to be given a counter example, would you mind sharing more details about your use-case?

Better would be a get_state(callback: Subscription<State>) function on the Store so I don't have to copy the state.

Wouldn't it be sufficient for Store<State, Reactor> to expose a get_state(&self) -> &State method? Better yet, we could consider implementing Deref<Target = State> for Store<State, Reactor> so that &Store may seamlessly be used where &State is expected.

It would also be splendid if I could register more than one reactor. For now I'm maintaining my own collection of listeners.

This should be possible out-of-the-box, tuples, arrays and slices of reactors are themselves reactors.

The same is true for Reducers by the way.

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Certainly, a simplified get_state() would be fine. As for a use-case, in the event of my application, there is a background thread that's generating state changes. At some point the front-end will send a query to display the current state. I don't want to wait for a reactor update if the background job takes a while to emit an action.

Thanks for the tip on the reactors and reducers, I'll look into using that strategy.

Update: now I remember why I wanted the callback to get the state: I'm using lazy_static and a Mutex to hold the application state. I don't think I can return a reference to the state to the caller when there's a mutex involved, but then again my Rust skills are not great.

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Sorry for the late response, I've somehow missed your update.

now I remember why I wanted the callback to get the state: I'm using lazy_static and a Mutex to hold the application state. I don't think I can return a reference to the state to the caller when there's a mutex involved, but then again my Rust skills are not great.

This shouldn't be of any concern, it is always be possible to write a method that gets a &'a S out of &'a Store<S, R>, regardless of what S is.

For example, If S is MyState(Mutex<SomeData>), you'll get a &MyState back. You're then free to lock the mutex to get access to SomeData if you like.

Does that make sense?

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Ah, right, thanks for pointing that out. It adds a step for the caller, but it's an alternative to copying, which is what I'm doing now.

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