import { ObservableInput, ObservedValueOf, OperatorFunction } from '../types';
/**
* Applies an accumulator function over the source Observable where the
* accumulator function itself returns an Observable, emitting values
* only from the most recently returned Observable.
*
* It's like {@link mergeScan}, but only the most recent
* Observable returned by the accumulator is merged into the outer Observable.
*
* @see {@link scan}
* @see {@link mergeScan}
* @see {@link switchMap}
*
* @param accumulator
* The accumulator function called on each source value.
* @param seed The initial accumulation value.
* @return A function that returns an observable of the accumulated values.
*/
export declare function switchScan>(accumulator: (acc: R, value: T, index: number) => O, seed: R): OperatorFunction>;
//# sourceMappingURL=switchScan.d.ts.map