import { Epic } from 'redux-observable';
/**
 * EpicManager runs a permanent epic alongside a swappable one, so feature
 * epics can be code-split without putting bootstrap requests at risk.
 *
 * How it works:
 * 1. The `rootEpic` is passed to `epicMiddleware.run()` at store creation.
 * 2. The permanent epic (core epics) subscribes immediately and stays
 *    subscribed for the lifetime of the store.
 * 3. After first paint the full feature epic module is dynamically imported
 *    and injected via `setFeatureEpic()`, which merges into the same output.
 *
 * The feature slot uses `switchMap`, so replacing it unsubscribes the previous
 * feature epic — but the permanent epic is outside that slot and is never torn
 * down. That ordering guarantee matters: `fetch` is promise-based, so
 * unsubscribing an in-flight request does not cancel it. A cancelled core
 * subscription would let a successful response arrive with no subscriber left
 * to reduce it, pinning `fetchState` at `In-Progress` forever.
 *
 * The permanent epic must therefore contain everything the app needs before
 * the feature bundle resolves, and the injected feature epic must NOT repeat
 * those epics — see `featureRootEpic` in `epic.ts`.
 */
export interface EpicManager {
    /** The root epic to pass to epicMiddleware.run(). */
    rootEpic: Epic;
    /** Replace the swappable feature epic (switchMap semantics). */
    setFeatureEpic: (epic: Epic) => void;
}
export declare function createEpicManager(permanentEpic: Epic): EpicManager;