rOACCT/node_modules/is-numberdd570dbc4621master
is-number
README.md
is-number ![NPM version](https://www.npmjs.com/package/is-number) ![NPM monthly downloads](https://npmjs.org/package/is-number) ![NPM total downloads](https://npmjs.org/package/is-number) ![Linux Build Status](https://travis-ci.org/jonschlinkert/is-number)
Returns true if the value is a finite number.
Please consider following this project's author, Jon Schlinkert, and consider starring the project to show your ❤️ and support.
Install
Install with npm:
sh $ npm install --save is-number
Why is this needed?
In JavaScript, it's not always as straightforward as it should be to reliably check if a value is a number. It's common for devs to use +, -, or Number() to cast a string value to a number (for example, when values are returned from user input, regex matches, parsers, etc). But there are many non-intuitive edge cases that yield unexpected results:
js console.log(+[]); //=> 0 console.log(+''); //=> 0 console.log(+' '); //=> 0 console.log(typeof NaN); //=> 'number'
This library offers a performant way to smooth out edge cases like these.
Usage
js const isNumber = require('is-number');
See the [tests](./test.js) for more examples.
true
js 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
Everything else is false, as you would expect:
js isNumber(Infinity); // false isNumber(NaN); // false isNumber(null); // false isNumber(undefined); // false isNumber(''); // false isNumber(' '); // false isNumber('foo'); // false isNumber([1]); // false isNumber([]); // false isNumber(function () {}); // false isNumber({}); // false
Release history
7.0.0
- Refactor. Now uses .isFinite if it exists.
- Performance is about the same as v6.0 when the value is a string or number. But it's now 3x-4x faster when the value is not a string or number.
6.0.0
- Optimizations, thanks to @benaadams.
5.0.0
Breaking changes
- removed support for instanceof Number and instanceof String
Benchmarks
As with all benchmarks, take these with a grain of salt. See the [benchmarks](./benchmark/index.js) for more detail.
# all v7.0 x 413,222 ops/sec ±2.02% (86 runs sampled) v6.0 x 111,061 ops/sec ±1.29% (85 runs sampled) parseFloat x 317,596 ops/sec ±1.36% (86 runs sampled) fastest is 'v7.0' # string v7.0 x 3,054,496 ops/sec ±1.05% (89 runs sampled) v6.0 x 2,957,781 ops/sec ±0.98% (88 runs sampled) parseFloat x 3,071,060 ops/sec ±1.13% (88 runs sampled) fastest is 'parseFloat,v7.0' # number v7.0 x 3,146,895 ops/sec ±0.89% (89 runs sampled) v6.0 x 3,214,038 ops/sec ±1.07% (89 runs sampled) parseFloat x 3,077,588 ops/sec ±1.07% (87 runs sampled) fastest is 'v6.0'
About
<details> <summary><strong>Contributing</strong></summary>
Pull requests and stars are always welcome. For bugs and feature requests, [please create an issue](../../issues/new).
</details>
<details> <summary><strong>Running Tests</strong></summary>
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:
sh $ npm install && npm test
</details>
<details> <summary><strong>Building docs</strong></summary>
_(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](.verb.md) readme template.)_
To generate the readme, run the following command:
sh $ npm install -g verbose/verb#dev verb-generate-readme && verb
</details>
Related projects
You might also be interested in these projects:
- is-plain-object: Returns true if an object was created by the Object constructor. | [homepage](https://github.com/jonschlinkert/is-plain-object "Returns true if an object was created by the Object constructor.")
- is-primitive: Returns true if the value is a primitive. | [homepage](https://github.com/jonschlinkert/is-primitive "Returns true if the value is a primitive. ")
- isobject: Returns true if the value is an object and not an array or null. | [homepage](https://github.com/jonschlinkert/isobject "Returns true if the value is an object and not an array or null.")
- kind-of: Get the native type of a value. | [homepage](https://github.com/jonschlinkert/kind-of "Get the native type of a value.")
Contributors
Commits | Contributor | |
---|---|---|
49 | jonschlinkert | |
5 | charlike-old | |
1 | benaadams | |
1 | realityking | |
Author
Jon Schlinkert
License
Copyright © 2018, Jon Schlinkert. Released under the [MIT License](LICENSE).
_This file was generated by verb-generate-readme, v0.6.0, on June 15, 2018._