import type { StringifyDates } from './typeutils.js';
/**
 * Convert a date to a string while retaining the timezone offset.
 *
 * For example, instead of converting to UTC and ending the string with a 'Z', like
 * JSON.stringify would do, this function will keep the timezone and append '-0600'
 * to signify that it was recorded on a device that was 6 hours off from UTC.
 */
export declare function dateToISOWithTZ(dt: Date): string;
/**
 * This function may be passed to JSON.stringify's second parameter to make Date
 * objects stringify with their time zone offset in tact.
 *
 * JSON.stringify(someobj, stringifyDateWithTZ)
 */
export declare function stringifyDateWithTZ(key: string, value: any): any;
/**
 * Recurse through an object to find Date objects and convert them to strings
 * with dateToISOWithTZ
 */
export declare function stringifyDates<T>(obj: T): StringifyDates<T>;