lepu-test-platform-web/node_modules/d/README.md

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 [![Build Status](https://travis-ci.org/medikoo/d.png)](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>