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node_modules/define-properties/README.md 2.66 KB
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  #define-properties <sup>[![Version Badge][npm-version-svg]][package-url]</sup>
  
  [![Build Status][travis-svg]][travis-url]
  [![dependency status][deps-svg]][deps-url]
  [![dev dependency status][dev-deps-svg]][dev-deps-url]
  [![License][license-image]][license-url]
  [![Downloads][downloads-image]][downloads-url]
  
  [![npm badge][npm-badge-png]][package-url]
  
  [![browser support][testling-svg]][testling-url]
  
  Define multiple non-enumerable properties at once. Uses `Object.defineProperty` when available; falls back to standard assignment in older engines.
  Existing properties are not overridden. Accepts a map of property names to a predicate that, when true, force-overrides.
  
  ## Example
  
  ```js
  var define = require('define-properties');
  var assert = require('assert');
  
  var obj = define({ a: 1, b: 2 }, {
  	a: 10,
  	b: 20,
  	c: 30
  });
  assert(obj.a === 1);
  assert(obj.b === 2);
  assert(obj.c === 30);
  if (define.supportsDescriptors) {
  	assert.deepEqual(Object.keys(obj), ['a', 'b']);
  	assert.deepEqual(Object.getOwnPropertyDescriptor(obj, 'c'), {
  		configurable: true,
  		enumerable: false,
  		value: 30,
  		writable: false
  	});
  }
  ```
  
  Then, with predicates:
  ```js
  var define = require('define-properties');
  var assert = require('assert');
  
  var obj = define({ a: 1, b: 2, c: 3 }, {
  	a: 10,
  	b: 20,
  	c: 30
  }, {
  	a: function () { return false; },
  	b: function () { return true; }
  });
  assert(obj.a === 1);
  assert(obj.b === 20);
  assert(obj.c === 3);
  if (define.supportsDescriptors) {
  	assert.deepEqual(Object.keys(obj), ['a', 'c']);
  	assert.deepEqual(Object.getOwnPropertyDescriptor(obj, 'b'), {
  		configurable: true,
  		enumerable: false,
  		value: 20,
  		writable: false
  	});
  }
  ```
  
  ## Tests
  Simply clone the repo, `npm install`, and run `npm test`
  
  [package-url]: https://npmjs.org/package/define-properties
  [npm-version-svg]: http://versionbadg.es/ljharb/define-properties.svg
  [travis-svg]: https://travis-ci.org/ljharb/define-properties.svg
  [travis-url]: https://travis-ci.org/ljharb/define-properties
  [deps-svg]: https://david-dm.org/ljharb/define-properties.svg
  [deps-url]: https://david-dm.org/ljharb/define-properties
  [dev-deps-svg]: https://david-dm.org/ljharb/define-properties/dev-status.svg
  [dev-deps-url]: https://david-dm.org/ljharb/define-properties#info=devDependencies
  [testling-svg]: https://ci.testling.com/ljharb/define-properties.png
  [testling-url]: https://ci.testling.com/ljharb/define-properties
  [npm-badge-png]: https://nodei.co/npm/define-properties.png?downloads=true&stars=true
  [license-image]: http://img.shields.io/npm/l/define-properties.svg
  [license-url]: LICENSE
  [downloads-image]: http://img.shields.io/npm/dm/define-properties.svg
  [downloads-url]: http://npm-stat.com/charts.html?package=define-properties