diff options
Diffstat (limited to 'node_modules/is-number/README.md')
| -rw-r--r-- | node_modules/is-number/README.md | 187 |
1 files changed, 187 insertions, 0 deletions
diff --git a/node_modules/is-number/README.md b/node_modules/is-number/README.md new file mode 100644 index 0000000..eb8149e --- /dev/null +++ b/node_modules/is-number/README.md @@ -0,0 +1,187 @@ +# is-number [](https://www.npmjs.com/package/is-number) [](https://npmjs.org/package/is-number) [](https://npmjs.org/package/is-number) [](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](https://github.com/jonschlinkert), and consider starring the project to show your :heart: and support. + +## Install + +Install with [npm](https://www.npmjs.com/): + +```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](https://github.com/verbose/verb-generate-readme), 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](https://www.npmjs.com/package/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](https://www.npmjs.com/package/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](https://www.npmjs.com/package/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](https://www.npmjs.com/package/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](https://github.com/jonschlinkert) | +| 5 | [charlike-old](https://github.com/charlike-old) | +| 1 | [benaadams](https://github.com/benaadams) | +| 1 | [realityking](https://github.com/realityking) | + +### Author + +**Jon Schlinkert** + +* [LinkedIn Profile](https://linkedin.com/in/jonschlinkert) +* [GitHub Profile](https://github.com/jonschlinkert) +* [Twitter Profile](https://twitter.com/jonschlinkert) + +### License + +Copyright © 2018, [Jon Schlinkert](https://github.com/jonschlinkert). +Released under the [MIT License](LICENSE). + +*** + +_This file was generated by [verb-generate-readme](https://github.com/verbose/verb-generate-readme), v0.6.0, on June 15, 2018._
\ No newline at end of file |