export declare const IMAGE_EXTENSIONS: string[];
/**
 *
 * @param str 判断一个字符串是否是地址
 * @returns boolean
 */
export declare function isUrl(str: string): boolean;
/**
 *
 * @param str 判断一个地址是否是图片
 * @returns boolean
 */
export declare function isImageUrl(str: string): boolean;