type SubscriberFunc<S> = (newState: S) => void;
export interface Atom<S> {
    set(newValue: S): void;
    subscriptions: Array<SubscriberFunc<S>>;
}
export declare function createAtom<S>(): Atom<S>;
export declare function useAtom<S>(atom: Atom<S>, initialState: S | (() => S)): [S, SubscriberFunc<S>];
export declare function useAtom<S = undefined>(atom: Atom<S | undefined>): [S | undefined, SubscriberFunc<S | undefined>];
export {};