import { Observable } from '../Observable';
/**
 * Opens a buffer immediately, then closes the buffer when the observable returned by calling `closingSelector` emits a value.
 * It that immediately opens a new buffer and repeats the process
 * @param {function} a function that takes no arguments and returns an Observable that signals buffer closure
 * @returns {Observable<T[]>} an observable of arrays of buffered values.
 */
export declare function bufferWhen<T>(closingSelector: () => Observable<any>): Observable<T[]>;