Yold

Yold is a zero-dependency library for working Naive ISO8061 dates. A naive date refers to a date representation that does not take into account time zones, daylight saving time, or any other specific time-related considerations. It simply represents a date without any additional information about the time or location.

Avoid issues with timezones being automatically added with new Date().

This library is designed for developers who need to work with ISO8061 date representations efficiently.

Install

To install Yold, use npm:

npm install yold

Usage

import { fromISODate, nextDay, toISOString } from 'yold';
// Parse an ISO8061 date string
const date = fromISODate("2024-07-22");
// Get the next day
const theNextDay = nextDay(date);
// Convert the date object back to an ISO8061 string
const iso = toISOString(theNextDay);
// Output the result
console.log(iso); // 2024-07-23

YOLD dates are ordered so you can use operators as you would with numbers

const d1 = fromISODate("2024-07-22");
const d2 = nextDay(d1);
console.log(d1 === d2);
console.log(d1 < d2); 
console.log(d1 > d2);

Why Yold

Yold stores date information by masking date components into a single number.

• Year: 13-bit number - year values ranging from 1 to 9999.
• Ordinal: 9-bit number - day values ranging from 1 to 366, accommodating leap years.
• Leap Year: 1-bit number - if a year is a leap year
• Day of the Week: 3-bit number - day of the week for the last day of the year before this year.