135 lines
		
	
	
		
			3.3 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
			
		
		
	
	
			135 lines
		
	
	
		
			3.3 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
| # D
 | |
| 
 | |
| ## Property descriptor factory
 | |
| 
 | |
| _Originally derived from [es5-ext](https://github.com/medikoo/es5-ext) package._
 | |
| 
 | |
| Defining properties with descriptors is very verbose:
 | |
| 
 | |
| ```javascript
 | |
| var Account = function () {};
 | |
| Object.defineProperties(Account.prototype, {
 | |
|   deposit: {
 | |
|     value: function () {
 | |
|       /* ... */
 | |
|     },
 | |
|     configurable: true,
 | |
|     enumerable: false,
 | |
|     writable: true
 | |
|   },
 | |
|   withdraw: {
 | |
|     value: function () {
 | |
|       /* ... */
 | |
|     },
 | |
|     configurable: true,
 | |
|     enumerable: false,
 | |
|     writable: true
 | |
|   },
 | |
|   balance: {
 | |
|     get: function () {
 | |
|       /* ... */
 | |
|     },
 | |
|     configurable: true,
 | |
|     enumerable: false
 | |
|   }
 | |
| });
 | |
| ```
 | |
| 
 | |
| D cuts that to:
 | |
| 
 | |
| ```javascript
 | |
| var d = require("d");
 | |
| 
 | |
| var Account = function () {};
 | |
| Object.defineProperties(Account.prototype, {
 | |
|   deposit: d(function () {
 | |
|     /* ... */
 | |
|   }),
 | |
|   withdraw: d(function () {
 | |
|     /* ... */
 | |
|   }),
 | |
|   balance: d.gs(function () {
 | |
|     /* ... */
 | |
|   })
 | |
| });
 | |
| ```
 | |
| 
 | |
| By default, created descriptor follow characteristics of native ES5 properties, and defines values as:
 | |
| 
 | |
| ```javascript
 | |
| { configurable: true, enumerable: false, writable: true }
 | |
| ```
 | |
| 
 | |
| You can overwrite it by preceding _value_ argument with instruction:
 | |
| 
 | |
| ```javascript
 | |
| d("c", value); // { configurable: true, enumerable: false, writable: false }
 | |
| d("ce", value); // { configurable: true, enumerable: true, writable: false }
 | |
| d("e", value); // { configurable: false, enumerable: true, writable: false }
 | |
| 
 | |
| // Same way for get/set:
 | |
| d.gs("e", value); // { configurable: false, enumerable: true }
 | |
| ```
 | |
| 
 | |
| ### Installation
 | |
| 
 | |
|     $ npm install d
 | |
| 
 | |
| To port it to Browser or any other (non CJS) environment, use your favorite CJS bundler. No favorite yet? Try: [Browserify](http://browserify.org/), [Webmake](https://github.com/medikoo/modules-webmake) or [Webpack](http://webpack.github.io/)
 | |
| 
 | |
| ### Other utilities
 | |
| 
 | |
| #### autoBind(obj, props) _(d/auto-bind)_
 | |
| 
 | |
| Define methods which will be automatically bound to its instances
 | |
| 
 | |
| ```javascript
 | |
| var d = require('d');
 | |
| var autoBind = require('d/auto-bind');
 | |
| 
 | |
| var Foo = function () { this._count = 0; };
 | |
| Object.defineProperties(Foo.prototype, autoBind({
 | |
|   increment: d(function () { ++this._count; });
 | |
| }));
 | |
| 
 | |
| var foo = new Foo();
 | |
| 
 | |
| // Increment foo counter on each domEl click
 | |
| domEl.addEventListener('click', foo.increment, false);
 | |
| ```
 | |
| 
 | |
| #### lazy(obj, props) _(d/lazy)_
 | |
| 
 | |
| Define lazy properties, which will be resolved on first access
 | |
| 
 | |
| ```javascript
 | |
| var d = require("d");
 | |
| var lazy = require("d/lazy");
 | |
| 
 | |
| var Foo = function () {};
 | |
| Object.defineProperties(Foo.prototype, lazy({ items: d(function () { return []; }) }));
 | |
| 
 | |
| var foo = new Foo();
 | |
| foo.items.push(1, 2); // foo.items array created and defined directly on foo
 | |
| ```
 | |
| 
 | |
| ## Tests [](https://travis-ci.org/medikoo/d)
 | |
| 
 | |
|     $ npm test
 | |
| 
 | |
| ## Security contact information
 | |
| 
 | |
| To report a security vulnerability, please use the [Tidelift security contact](https://tidelift.com/security). Tidelift will coordinate the fix and disclosure.
 | |
| 
 | |
| ---
 | |
| 
 | |
| <div align="center">
 | |
| 	<b>
 | |
| 		<a href="https://tidelift.com/subscription/pkg/npm-d?utm_source=npm-d&utm_medium=referral&utm_campaign=readme">Get professional support for d with a Tidelift subscription</a>
 | |
| 	</b>
 | |
| 	<br>
 | |
| 	<sub>
 | |
| 		Tidelift helps make open source sustainable for maintainers while giving companies<br>assurances about security, maintenance, and licensing for their dependencies.
 | |
| 	</sub>
 | |
| </div>
 |