/**
 * @method truncate
 * @param  {Number} letters max letters numbers
 * @param  {String} word    word to analyze
 * @return {String} truncated word
 */
export declare const truncate: (letters: number, word: string) => string;
/**
 * @method randomString
 * @param  {Number} length
 * @return {String}
 */
export declare const randomString: (length: number) => string;
/**
 * @method toLowerCase
 * @param  {String}       text
 * @return {String}
 */
export declare const toLowerCase: <T extends string>(text: T) => T | string;
/**
 * @method isString
 * @param  {any} value
 * @return {Boolean}
 */
export declare const isString: (value: unknown) => boolean;