import { Header } from './Header';
export declare class PromiseUtils {
    /**
     *  Promise wrapper for XMLHttpRequest.
     *  @static
     *  @public
     *  @param {string} url - Url of resource to request.
     *  @param {string} method - HTTP verb used to request resource.
     *  @param {string} responseType - Expected response type most of the time either "arraybuffer" or "text".
     *  @param {Header[]} headers - Headers for the request.
     *  @return {Promise<XMLHttpRequest>} - promise with the response.
     */
    static getRequestAsync(url: string, method?: string, responseType?: XMLHttpRequestResponseType, headers?: Header[]): Promise<XMLHttpRequest>;
    /**
     *  Promise chain that keeps executing action function until predicate in condition function is satisfied.
     *  @static
     *  @public
     *  @param {Function} condition - funtion returning boolean.
     *  @param {Function} action - action function.
     */
    static promiseWhile(condition: () => boolean, action: () => void): Promise<any>;
}