import { Observable } from 'rxjs';
import { WebsocketData } from '../websocket-insider';
export declare function transformSourceData<T, U>(params: {
    source$: Observable<WebsocketData<T>>;
    update?: (originSource: WebsocketData<T>, updateSource: WebsocketData<T>) => WebsocketData<T>;
    transform: (source: WebsocketData<T>) => U;
}): Observable<U>;