Typescript port of js-money. Implementation of the Money value object.
npm install ts-money
TS Money is a Typescript port of the great js-money package, which is an implementation of Martin Fowlers Money pattern.
``sh`
npm install ts-money
First we need to import the library.
`typescript`
import { Money, Currencies } from 'ts-money'
or in javascript:
`javascript`
const TsMoney = require('ts-money')
const Money = TsMoney.Money
const Currencies = TsMoney.Currencies
There are multiple options of what to pass into the constructor to create a new Money instance:
* amount as number, currency as string
* amount as number, currency as object
* object with amount and currency fields (only with fromInteger and fromDecimal methods)
Amounts can be supplied either as integers or decimal numbers.
Instances of Money are immutable and each arithmetic operation will return a new instance of the object.
When using decimals the library will allow only decimals with the precision allowed by the currencies smallest unit.
`typescript
const fiveEur = new Money(500, Currencies.EUR)
const tenDollars = Money.fromInteger({ amount: 1000, currency: Currencies.USD })
const someDollars = Money.fromDecimal(15.25, 'USD')
// the following will fail and throw an Error since USD allows for 2 decimals
const moreDollars = Money.fromDecimal(15.3456, Currencies.USD)
// but with rounder function provider the following will work
const someMoreDollars = Money.fromDecimal(15.12345, 'USD', Math.ceil)
`
The Currency interface hold the following properties:
`typescript`
interface Currency {
symbol: string
name: string
symbol_native: string
decimal_digits: number
rounding: number
code: string
name_plural: string
}
Ex:
`typescript
import { Currency } from 'ts-money'
const usd: Currency = {
"symbol": "$",
"name": "US Dollar",
"symbol_native": "$",
"decimal_digits": 2,
"rounding": 0,
"code": "USD",
"name_plural": "US dollars"
}
`
Arithmetic operations involving multiple objects are only possible on instances with the same currency and will throw an Error otherwise.
`typescript
const fiveEur = new Money(500, Currencies.EUR) // 5 EUR
// add
fiveEur.add(new Money(250, Currencies.EUR)) // 7.50 EUR
// subtract
fiveEur.subtract(new Money(470, Currencies.EUR)) // 0.30 EUR
// multiply
fiveEur.multiply(1.2345) // 6.17 EUR
fiveEur.multiply(1.2345, Math.ceil) // 6.18 EUR
// divide
fiveEur.divide(2.3456) // 2.13 EUR
fiveEur.divide(2.3456, Math.ceil) // 2.14 EUR
`
Will divide the funds based on the ratio without loosing any pennies.
`typescript
const tenEur = new Money(1000, Currencies.EUR)
// divide 10 EUR into 3 parts
const shares = tenEur.allocate([1,1,1])
// returns an array of Money instances worth [334,333,333]
// split 5 EUR 70/30
const fiveEur = new Money(500, Currencies.EUR)
const shares = fiveEur.allocate([70,30])
// returns an array of money [350,150]
`
Two objects are equal when they are of the same amount and currency.
Trying to compare 2 objects with different currencies will throw an Error.
`typescript
const fiveEur = new Money(500, Currencies.EUR)
const anotherFiveEur = new Money(500, Currencies.EUR)
const sevenEur = new Money(700, Currencies.EUR)
const fiveDollars = new Money(500, Currencies.USD)
fiveEur.equals(fiveDollars) // return false
fiveEur.equals(anotherFiveEur) // return true
fiveEur.compare(sevenEur) // return -1
sevenEur.compare(fiveEur) // return 1
fiveEur.compare(anotherFiveEur) // return 0
fiveEur.compare(fileDollars) // throw Error
fiveEur.greaterThan(sevenEur) // return false
fiveEur.greaterThanOrEqual(sevenEur) // return false
fiveEur.lessThan(sevenEur) // return true
fiveEur.lessThanOrEqual(fiveEur) // return true
`
Some changes have been made compared with the javascript version:
Currencies are now exported in a standalone object:
`typescript
import { Money, Currencies } from 'ts-money'
Currencies.LTC = {
symbol: "Ł",
name: "Litecoin",
symbol_native: "Ł",
decimal_digits: 8,
rounding: 0,
code: "LTC",
name_plural: "Litecoins"
}
const m1 = new Money(12, 'LTC')
const m2 = new Money(234, Currencies.USD)
const m3 = new Money(543, Currencies.LTC)
`
Money accepts currencies as case insensitive:
`typescript`
const m1 = new Money(1, 'usd')
const m2 = new Money(2, 'USD')
const m3 = new Money(3, 'Usd')
`sh`
npm install
`sh`
npm run build
`sh``
npm test
> TS Money is an open source library and is completely free to use.
>
> If you find this project useful and would like to support its development, consider making a donation.
