is-number
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Package description
The is-number npm package is a simple utility for checking if a value is a number. It works with various types of numeric representations, including strings that can be coerced to numbers, and provides a straightforward API for determining if a value can be considered a number in JavaScript.
Check if a value is a number
This feature allows you to check if a value is a number, including numeric strings.
const isNumber = require('is-number');
console.log(isNumber(5)); // true
console.log(isNumber('5')); // true
console.log(isNumber('five')); // falseCheck if a value is not a number
This feature allows you to check if a value is not a number, including strings that cannot be coerced to numbers and other non-numeric types.
const isNumber = require('is-number');
console.log(isNumber('foo')); // false
console.log(isNumber([1, 2, 3])); // falseCheck if a value is a finite number
This feature allows you to check if a value is a finite number, excluding Infinity, -Infinity, and NaN.
const isNumber = require('is-number');
console.log(isNumber(Infinity)); // false
console.log(isNumber(-Infinity)); // false
console.log(isNumber(NaN)); // falseThe isnumeric package offers similar functionality to is-number by checking if a value is numeric. It is similar in its simplicity and direct approach.
The numerable package is a more comprehensive library for number validation and formatting. It provides additional functionality compared to is-number, such as parsing and formatting numbers with localization support.
This package is part of the validate.io suite and checks if a value is a number primitive. It is more strict than is-number as it does not consider numeric strings to be numbers.
Readme
Returns true if the value is a number. comprehensive tests.
Install with npm:
$ npm install --save is-number
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');
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'
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'
true if the value is a primitive. | homepagePull requests and stars are always welcome. For bugs and feature requests, please create an issue.
(This document was generated by verb-generate-readme (a verb generator), please don't edit the readme directly. Any changes to the readme must be made in .verb.md.)
To generate the readme and API documentation with verb:
$ npm install -g verb verb-generate-readme && verb
Install dev dependencies:
$ npm install -d && npm test
Jon Schlinkert
Copyright © 2016, Jon Schlinkert. Released under the MIT license.
This file was generated by verb-generate-readme, v0.1.30, on September 10, 2016.
FAQs
Returns true if a number or string value is a finite number. Useful for regex matches, parsing, user input, etc.
The npm package is-number receives a total of 59,457,952 weekly downloads. As such, is-number popularity was classified as popular.
We found that is-number demonstrated a not healthy version release cadence and project activity because the last version was released a year ago. It has 3 open source maintainers collaborating on the project.
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