import { type TAnyFeature } from 'feature-core';
import type { TListenerContext, TState } from 'feature-state';
/**
 * Calls `callback` immediately with the current state value, then on every future change,
 * matching `state.subscribe()`. The callback may return a cleanup function that runs before
 * the next call and on unmount. Pass `null` or `undefined` as `state` to opt out without
 * conditionally calling the hook.
 */
export declare function useSubscriber<GValue, GFeatures extends TAnyFeature[]>(state: TState<GValue, GFeatures> | null | undefined, callback: TUseSubscriberCallback<GValue>): void;
/** Receives the current listener context immediately, then on each future change. */
export type TUseSubscriberCallback<GValue> = (context: TListenerContext<GValue>) => (() => void) | Promise<void> | void;