import { Subscription } from 'rxjs';
import { StoreEvent } from './storeEvents';
import { getStateMutationMetadata } from './storeMetadata';
export type StoreExtensionApi = Readonly<{
    getStateMutationMetadata: typeof getStateMutationMetadata;
}>;
export type StoreExtension<State> = (api: StoreExtensionApi) => {
    onStoreEvent?: (event: StoreEvent<State>) => void;
};
export declare function registerStoreExtension(extension: StoreExtension<unknown>): Subscription;