export declare abstract class PromiseUtil {
    static try(f: any): Promise<any>;
    static map(arr: any[], f: (this: void, value: any, index: number, array: any[]) => any): Promise<any[]>;
    static mapSeries(arr: any, f: any): Promise<any[]>;
    static sleepPromise<T>(ms: any, v?: T): Promise<T>;
}