import type { Observable, Observer } from 'rxjs';
/**
 * React hook that subscribes to an observable using `useEffect`.
 *
 * The subscription is created when the observable or observer changes, and
 * torn down on unmount or re-subscription.
 *
 * @template T - The value type emitted by the observable.
 * @param observable - The observable to subscribe to.
 * @param observer - An observer or `next` callback.
 * @param teardown - Optional teardown function added to the subscription.
 */
export declare const useObservableSubscription: <T>(observable: Observable<T>, observer?: Partial<Observer<T>> | ((value: T) => void), teardown?: () => void) => void;
/**
 * React hook that subscribes to an observable using `useLayoutEffect`,
 * ensuring the subscription is active before the browser paints.
 *
 * Useful when the observable drives ref updates or other commit-phase side effects.
 *
 * @template T - The value type emitted by the observable.
 * @param observable - The observable to subscribe to.
 * @param observer - An observer or `next` callback.
 * @param teardown - Optional teardown function added to the subscription.
 */
export declare const useObservableLayoutSubscription: <T>(observable: Observable<T>, observer?: Partial<Observer<T>> | ((value: T) => void), teardown?: () => void) => void;