Comma number


Install

``sh
$ npm install --save comma-number
`




Usage

`js
const commaNumber = require('comma-number')

commaNumber(1000) // "1,000"
commaNumber(-1000) // "-1,000"
commaNumber(-1000, '.') // "-1.000"

commaNumber(1000.12) // "1,000.12"
commaNumber(-1000.12) // "-1,000.12"
commaNumber('-1000,12', '.', ',') // "-1.000,12"

// make a new function using custom separator and decimal char:
const format = commaNumber.bindWith('_', '!')
// use it as you would commaNumber().
format(1000) // "1_000"
format(-1000) // "-1_000"
format(1000.12) // "1_000!12"
format(-1000.12) // "-1_000!12"
`




Version 2 Changes

Revised implementation changes the API a bit:

1. input with a type other than string and number is returned as is, not as '0'.
2. supports decimals in the number
3. a string number may use an alternate decimal character, specify it as the third argument
4. added a bindWith function to use a currying style to bind options for a reusable format function.

Other changes:

1. Added benchmarking to test implementation performance
2. added code coverage
3. added new badges in this README
4. added more versions to the Travis CI config




API

$3

Parameters:

* number : {(Number|String)} Number to format
* separator : {String} Value used to separate numbers
* decimalChar : {String} Value used to separate the decimal value

Returns:

* {String} Comma formatted number




$3

The commaNumber function accepts these same parameters as the second and third params. This prevents using currying to bind them and reuse that bound function.

The bindWith function accepts the options and returns a function bound with them.

`javascript
// the default commaNumber uses a comma separator and period for decimal char.
var commaNumber = require('comma-number')
// can build a custom version using bindWith.
, format = commaNumber.bindWith('_', '!')
, result1 = commaNumber(1234567.89)
, result2 = format('1234567.89')

console.log(result1) // outputs: 1,234,567.89
console.log(result2) // outputs: 1_234_567!89
`




Scripts for Testing, Benchmarking, and Code Coverage

`sh


run tests via tap

$ npm test

benchmark current implementation versus previous

npm run benchmark

get coverage info by default with testing:

npm test
``

Performance Comparison

The rewrite has a considerable performance increase from the previous version.

I converted the benchmark output from my machine into a table.

It compares the performance of version 1.1.0 with 2.0.0. The inputs with decimals can only be processed by the new version so those show as "invalid" for the previous version.

MIT License