Jalaali

Golang implementation of Jalaali JS and Jalaali Python implementations of Jalaali (Jalali, Persian, Khayyami, Khorshidi, Shamsi) convertion to Gregorian calendar system and vice-versa.

This implementation is based on an algorithm by Kazimierz M. Borkowski. Borkowski claims that this algorithm works correctly for 3000 years!

Documentation on API is available here at Go official documentation site.

Installation

Use go get on this repository:

$ go get -u github.com/jalaali/go-jalaali

Usage

Current time

Jalaali.Now() returns a Jalaali instance wrapping the current time. You can use all the methods from the Go time package on it.

package main

import (
	"jalaali"
)

func main() {
	j := jalaali.Now()
}

From a time instance

Jalaali.From(t) wraps an existing time.Time instance. You can then work with it the same way you work with the time package.

package main

import (
	"jalaali"
	"time"
)

func main() {
	t := time.Date(2014, 8, 4, 0, 0, 0, 0, time.UTC)
	j := jalaali.From(t)
}

Converting dates

Convert a Gregorian date to Jalaali with ToJalaali, and back with ToGregorian. Both return the date components plus an error that is non-nil when the input is invalid.

package main

import (
	"jalaali"
	"time"
)

func main() {
	// Gregorian to Jalaali
	jy, jm, jd, err := jalaali.ToJalaali(2014, time.August, 4)
	if err != nil {
		panic(err)
	}
	// jy = 1393, jm = jalaali.Mordad, jd = 13

	// Jalaali to Gregorian
	gy, gm, gd, err := jalaali.ToGregorian(1393, jalaali.Mordad, 13)
	if err != nil {
		panic(err)
	}
	// gy = 2014, gm = time.August, gd = 4
}

Formatting

Call the JFormat method of a Jalaali instance and pass it the same formatting layout used by the Go time package. The output is a Jalaali date using Persian digits and words.

package main

import (
	"jalaali"
	"time"
)

func main() {
	iran, _ := time.LoadLocation("Asia/Tehran")
	j := jalaali.From(time.Date(2001, 2, 3, 15, 17, 1, 0, iran))

	// "۱۳۷۹ بهمن شنبه ۱۵ ۰۳ ۱۷ ۰۱ بعدازظهر"
	formatted, err := j.JFormat("2006 January Monday 15 03 17 01 PM")
	if err != nil {
		panic(err)
	}
}

Utilities

• IsValidDate(jy, jm, jd) returns true if the given Jalaali date is valid.
• IsLeapYear(jy) returns true if the given Jalaali year is a leap year.
• MonthLength(jy, jm) returns the number of days in the given Jalaali month.