import Joi from 'joi';
/**
 * 格式化字符串
 */
export declare function inspectLimit(data: any, options?: {
    depth: number;
    limit: number;
}): string;
/**
 * 获取随机字符串
 */
export declare function randomString(length: number, chars?: string): string;
/**
 * 使用 Joi 检查+转换数据源参数
 */
export declare function checkParams<T = any>(params: T, schema: Joi.ObjectSchema): T;
/**
 * 是否为有效的字符串
 */
export declare function isValidString(str: any): str is string;
/**
 * 是否为有效的数组
 */
export declare function isValidArray<T = any>(arr: any): arr is Array<T>;