is-number

Returns true if the value is a number. comprehensive tests.

Please consider following this project's author, Jon Schlinkert, and consider starring the project to show your :heart: and support.

Install

Install with npm:

$ npm install --save is-number

Usage

To understand some of the rationale behind the decisions made in this library (and to learn about some oddities of number evaluation in JavaScript), see this gist.

var isNumber = require('is-number');

true

See the tests for more examples.

isNumber(5e3)      //=> 'true'
isNumber(0xff)     //=> 'true'
isNumber(-1.1)     //=> 'true'
isNumber(0)        //=> 'true'
isNumber(1)        //=> 'true'
isNumber(1.1)      //=> 'true'
isNumber(10)       //=> 'true'
isNumber(10.10)    //=> 'true'
isNumber(100)      //=> 'true'
isNumber('-1.1')   //=> 'true'
isNumber('0')      //=> 'true'
isNumber('012')    //=> 'true'
isNumber('0xff')   //=> 'true'
isNumber('1')      //=> 'true'
isNumber('1.1')    //=> 'true'
isNumber('10')     //=> 'true'
isNumber('10.10')  //=> 'true'
isNumber('100')    //=> 'true'
isNumber('5e3')    //=> 'true'
isNumber(parseInt('012'))   //=> 'true'
isNumber(parseFloat('012')) //=> 'true'

False

See the tests for more examples.

isNumber('foo')             //=> 'false'
isNumber([1])               //=> 'false'
isNumber([])                //=> 'false'
isNumber(function () {})    //=> 'false'
isNumber(Infinity)          //=> 'false'
isNumber(NaN)               //=> 'false'
isNumber(new Array('abc'))  //=> 'false'
isNumber(new Array(2))      //=> 'false'
isNumber(new Buffer('abc')) //=> 'false'
isNumber(null)              //=> 'false'
isNumber(undefined)         //=> 'false'
isNumber({abc: 'abc'})      //=> 'false'

About

Pull requests and stars are always welcome. For bugs and feature requests, please create an issue.

Running and reviewing unit tests is a great way to get familiarized with a library and its API. You can install dependencies and run tests with the following command:

$ npm install && npm test

(This project‘s readme.md is generated by verb, please don’t edit the readme directly. Any changes to the readme must be made in the .verb.md readme template.)

To generate the readme, run the following command:

$ npm install -g verbose/verb#dev verb-generate-readme && verb

Related projects

You might also be interested in these projects:

even: Get the even numbered items from an array. | homepage
is-even: Return true if the given number is even. | homepage
is-odd: Returns true if the given number is odd. | homepage
is-primitive: Returns true if the value is a primitive. | homepage
kind-of: Get the native type of a value. | homepage
odd: Get the odd numbered items from an array. | homepage

Contributors

Commits	Contributor
38	jonschlinkert
5	charlike

Author

Jon Schlinkert

License

This file was generated by verb-generate-readme, v0.6.0, on October 17, 2017.