import { AsyncIterableX } from '../../asynciterable/asynciterablex';
/**
 * @ignore
 */
export declare function distinctUntilChangedProto<TSource, TKey>(this: AsyncIterableX<TSource>, keySelector?: (value: TSource) => TKey | Promise<TKey>, comparer?: (x: TKey, y: TKey) => boolean | Promise<boolean>): AsyncIterableX<TSource>;
declare module '../../asynciterable/asynciterablex' {
    interface AsyncIterableX<T> {
        distinctUntilChanged: typeof distinctUntilChangedProto;
    }
}