export declare function toCenterLine(str: string): string;
export declare function toUpper(str: string): string;
export declare function toSmallHump(str: string): string;
export declare function walk<T>(arr: T[], callback: (obj: T, parent: T[]) => void, parent?: T[]): void;
export declare function getFormatDateStr(dateStr?: number | string | Date): string;
/**
 * 从try{}catch(err){}语句中获取到error的msg
 */
export declare function getErrorMessage(error: Error | unknown): string;
/**
 * Retries a command a few times. Will return after the first
 * successful attempt, or will throw after specifies attempts count.
 */
export declare function retry<T extends Function>(count: number | undefined, fn: T): (...args: any[]) => Promise<any>;