# define-property [](https://www.npmjs.com/package/define-property) [](https://npmjs.org/package/define-property) [](https://npmjs.org/package/define-property) [](https://travis-ci.org/jonschlinkert/define-property) > Define a non-enumerable property on an object. Uses Reflect.defineProperty when available, otherwise Object.defineProperty. 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 define-property ``` ## Release history See [the CHANGELOG](changelog.md) for updates. ## Usage **Params** * `object`: The object on which to define the property. * `key`: The name of the property to be defined or modified. * `value`: The value or descriptor of the property being defined or modified. ```js var define = require('define-property'); var obj = {}; define(obj, 'foo', function(val) { return val.toUpperCase(); }); // by default, defined properties are non-enumberable console.log(obj); //=> {} console.log(obj.foo('bar')); //=> 'BAR' ``` **defining setters/getters** Pass the same properties you would if using [Object.defineProperty](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/defineProperty) or [Reflect.defineProperty](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Reflect/defineProperty). ```js define(obj, 'foo', { set: function() {}, get: function() {} }); ``` ## 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: * [assign-deep](https://www.npmjs.com/package/assign-deep): Deeply assign the enumerable properties and/or es6 Symbol properies of source objects to the target… [more](https://github.com/jonschlinkert/assign-deep) | [homepage](https://github.com/jonschlinkert/assign-deep "Deeply assign the enumerable properties and/or es6 Symbol properies of source objects to the target (first) object.") * [extend-shallow](https://www.npmjs.com/package/extend-shallow): Extend an object with the properties of additional objects. node.js/javascript util. | [homepage](https://github.com/jonschlinkert/extend-shallow "Extend an object with the properties of additional objects. node.js/javascript util.") * [merge-deep](https://www.npmjs.com/package/merge-deep): Recursively merge values in a javascript object. | [homepage](https://github.com/jonschlinkert/merge-deep "Recursively merge values in a javascript object.") * [mixin-deep](https://www.npmjs.com/package/mixin-deep): Deeply mix the properties of objects into the first object. Like merge-deep, but doesn't clone. | [homepage](https://github.com/jonschlinkert/mixin-deep "Deeply mix the properties of objects into the first object. Like merge-deep, but doesn't clone.") ### Contributors | **Commits** | **Contributor** | | --- | --- | | 28 | [jonschlinkert](https://github.com/jonschlinkert) | | 1 | [doowb](https://github.com/doowb) | ### Author **Jon Schlinkert** * Connect with me on [linkedin/in/jonschlinkert](https://linkedin.com/in/jonschlinkert) * Follow me on [github/jonschlinkert](https://github.com/jonschlinkert) * Follow me on [twitter/jonschlinkert](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 January 25, 2018._