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Chrono

GitHub code size in bytes deno doc GitHub

A date utility library that extends the native Date object.

Features

  • Date and time manipulation
  • Fully compatible with the native Date object

How to use

Basic usage:

import { Chrono } from "https://raw.githubusercontent.com/ymonb1291/chrono/main/mod.ts";

const chrono = new Chrono();
chrono.addDay(1);

Compatibility

The class Chrono extends the Date object with additional functionalities. All functionalities from Date are accounted for.

The following two lines of code return the timestamp of the current date and time:

Chrono.now();
Date.now();

And so are the following two:

new Chrono().toLocaleString();
new Date().toLocaleString();

A Chrono object fully complies with the Date interface. The following example is valid:

function useDate(date: Date) {}
useDate(new Chrono());

However, a Date type does not allow objects of type Chrono.

function useChrono(date: Chrono) {}
useChrono(new Date());

Methods

Chrono.prototype.addDay

Method signature

Chrono.addDay(n?: number): number
  • Parameter:
    • n: (optional) parameter of type number which defaults to 1 and defines the number of days to add to the current date.
  • Returns: a value of type number representing the timestamp after execution

Example

const chrono = new Chrono("Feb 01 2020 12:00:00.000");
const res = chrono.addDay(2);
console.log(chrono.toLocaleString()); // Mon Feb 03 2020 12:00:00 GMT+0100 (CET)
console.log(res);                     // 1580727600000

Chrono.prototype.addHour

Method signature

Chrono.addHour(n?: number): number
  • Parameter:
    • n: (optional) parameter of type number which defaults to 1 and defines the number of hours to add to the current time.
  • Returns: a value of type number representing the timestamp after execution

Example

const chrono = new Chrono("Feb 01 2020 12:00:00.000");
const res = chrono.addHour(2);
console.log(chrono.toLocaleString()); // Sat Feb 01 2020 14:00:00 GMT+0100 (CET)
console.log(res);                     // 1580562000000

Chrono.prototype.addMinute

Method signature

Chrono.addMinute(n?: number): number
  • Parameter:
    • n: (optional) parameter of type number which defaults to 1 and defines the number of minutes to add to the current time.
  • Returns: a value of type number representing the timestamp after execution

Example

const chrono = new Chrono("Feb 01 2020 12:00:00.000");
const res = chrono.addMinute(2);
console.log(chrono.toLocaleString()); // Sat Feb 01 2020 12:02:00 GMT+0100 (CET)
console.log(res);                     // 1580554920000

Chrono.prototype.addMonth

Method signature

Chrono.addMonth(n?: number): number
  • Parameter:
    • n: (optional) parameter of type number which defaults to 1 and defines the number of months to add to the current date.
  • Returns: a value of type number representing the timestamp after execution

Example

const chrono = new Chrono("Feb 01 2020 12:00:00.000");
const res = chrono.addMonth(2);
console.log(chrono.toLocaleString()); // Wed Apr 01 2020 12:00:00 GMT+0200 (CEST)
console.log(res);                     // 1585735200000

Chrono.prototype.addSecond

Method signature

Chrono.addSecond(n?: number): number
  • Parameter:
    • n: (optional) parameter of type number which defaults to 1 and defines the number of seconds to add to the current time.
  • Returns: a value of type number representing the timestamp after execution

Example

const chrono = new Chrono("Feb 01 2020 12:00:00.000");
const res = chrono.addSecond(2);
console.log(chrono.toLocaleString()); // Sat Feb 01 2020 12:00:02 GMT+0100 (CET)
console.log(res);                     // 1580554802000

Chrono.prototype.addWeek

Method signature

Chrono.addWeek(n?: number): number
  • Parameter:
    • n: (optional) parameter of type number which defaults to 1 and defines the number of weeks to add to the current date.
  • Returns: a value of type number representing the timestamp after execution

Example

const chrono = new Chrono("Feb 01 2020 12:00:00.000");
const res = chrono.addWeek(2);
console.log(chrono.toLocaleString()); // Sat Feb 15 2020 12:00:00 GMT+0100 (CET)
console.log(res);                     // 1581764400000

Chrono.prototype.addYear

Method signature

Chrono.addYear(n?: number): number
  • Parameter:
    • n: (optional) parameter of type number which defaults to 1 and defines the number of years to add to the current date.
  • Returns: a value of type number representing the timestamp after execution

Example

const chrono = new Chrono("Feb 01 2020 12:00:00.000");
const res = chrono.addYear(2);
console.log(chrono.toLocaleString()); // Tue Feb 01 2022 12:00:00 GMT+0100 (CET)
console.log(res);                     // 1643713200000

Chrono.prototype.isLeapYear

Method signature

Chrono.isLeapYear(): boolean
  • Returns: a value of type boolean which is true when the year is a leap year

Example

const chrono = new Chrono("Jan 01 2020 00:00:00");
console.log(chrono.isLeapYear());    // true

Chrono.prototype.isUTCLeapYear

Method signature

Chrono.isUTCLeapYear(): boolean
  • Returns: a value of type boolean which is true when the UTC year is a leap year

Example

const chrono = new Chrono("Jan 01 2020 00:00:00");
console.log(chrono.isUTCLeapYear());    // false

Chrono.prototype.set

Method signature

Chrono.set(time: number | Date | Chrono): number
  • Parameter:
    • time: parameter of type number | Date | Chrono representing a valid date
  • Returns: a value of type number representing the timestamp after execution

Example

const chrono = new Chrono("Feb 01 2020 12:00:00.000");
const res = chrono.set(new Date(946681200000));
console.log(chrono.toLocaleString()); // Sat Jan 01 2000 00:00:00 GMT+0100 (CET)
console.log(res);                     // 946681200000

Chrono.prototype.substractDay

Method signature

Chrono.substractDay(n?: number): number
  • Parameter:
    • n: (optional) parameter of type number which defaults to 1 and defines the number of days to substract to the current date.
  • Returns: a value of type number representing the timestamp after execution

Example

const chrono = new Chrono("Feb 01 2020 12:00:00.000");
const res = chrono.substractDay(2);
console.log(chrono.toLocaleString()); // Thu Jan 30 2020 12:00:00 GMT+0100 (CET)
console.log(res);                     // 1580382000000

Chrono.prototype.substractHour

Method signature

Chrono.substractHour(n?: number): number
  • Parameter:
    • n: (optional) parameter of type number which defaults to 1 and defines the number of hours to substract to the current time.
  • Returns: a value of type number representing the timestamp after execution

Example

const chrono = new Chrono("Feb 01 2020 12:00:00.000");
const res = chrono.substractHour(2);
console.log(chrono.toLocaleString()); // Sat Feb 01 2020 10:00:00 GMT+0100 (CET)
console.log(res);                     // 1580547600000

Chrono.prototype.substractMinute

Method signature

Chrono.substractMinute(n?: number): number
  • Parameter:
    • n: (optional) parameter of type number which defaults to 1 and defines the number of minutes to substract to the current time.
  • Returns: a value of type number representing the timestamp after execution

Example

const chrono = new Chrono("Feb 01 2020 12:00:00.000");
const res = chrono.substractMinute(2);
console.log(chrono.toLocaleString()); // Sat Feb 01 2020 11:58:00 GMT+0100 (CET)
console.log(res);                     // 1580554680000

Chrono.prototype.substractMonth

Method signature

Chrono.substractMonth(n?: number): number
  • Parameter:
    • n: (optional) parameter of type number which defaults to 1 and defines the number of months to substract to the current date.
  • Returns: a value of type number representing the timestamp after execution

Example

const chrono = new Chrono("Feb 01 2020 12:00:00.000");
const res = chrono.substractMonth(2);
console.log(chrono.toLocaleString()); // Sun Dec 01 2019 12:00:00 GMT+0100 (CET)
console.log(res);                     // 1575198000000

Chrono.prototype.substractSecond

Method signature

Chrono.substractSecond(n?: number): number
  • Parameter:
    • n: (optional) parameter of type number which defaults to 1 and defines the number of seconds to substract to the current time.
  • Returns: a value of type number representing the timestamp after execution

Example

const chrono = new Chrono("Feb 01 2020 12:00:00.000");
const res = chrono.substractSecond(2);
console.log(chrono.toLocaleString()); // Sat Feb 01 2020 11:59:58 GMT+0100 (CET)
console.log(res);                     // 1580554798000

Chrono.prototype.substractWeek

Method signature

Chrono.substractWeek(n?: number): number
  • Parameter:
    • n: (optional) parameter of type number which defaults to 1 and defines the number of weeks to substract to the current date.
  • Returns: a value of type number representing the timestamp after execution

Example

const chrono = new Chrono("Feb 01 2020 12:00:00.000");
const res = chrono.substractWeek(2);
console.log(chrono.toLocaleString()); // Sat Jan 18 2020 12:00:00 GMT+0100 (CET)
console.log(res);                     // 1579345200000

Chrono.prototype.substractYear

Method signature

Chrono.substractYear(n?: number): number
  • Parameter:
    • n: (optional) parameter of type number which defaults to 1 and defines the number of years to substract to the current date.
  • Returns: a value of type number representing the timestamp after execution

Example

const chrono = new Chrono("Feb 01 2020 12:00:00.000");
const res = chrono.substractYear(2);
console.log(chrono.toLocaleString()); // Thu Feb 01 2018 12:00:00 GMT+0100 (CET)
console.log(res);                     // 1517482800000

Chrono.prototype.toArray

Method signature

Chrono.toArray(): [number, number, number, number, number, number, number]
  • Returns: an array of 7 values of type number representing [year, month, date, hours, minutes, seconds, milliseconds]

Example

const chrono = new Chrono("Feb 01 2020 00:00:00");
console.log(chrono.toUTCArray());   // [2020, 1, 1, 0, 0, 0, 0]

Chrono.prototype.toUTCArray

Method signature

Chrono.toUTCArray(): [number, number, number, number, number, number, number]
  • Returns: an array of 7 values of type number representing [UTCYear, UTCMonth, UTCDate, UTCHours, UTCMinutes, UTCSeconds, UTCMilliseconds]

Example

const chrono = new Chrono("Feb 01 2020 00:00:00");
console.log(chrono.toUTCArray());   // [2020, 0, 31, 23, 0, 0, 0]

Contributions

PRs are welcome!