Originally derived from es5-ext package.
Defining properties with descriptors is very verbose:
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:
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:
{ configurable: true, enumerable: false, writable: true }
You can overwrite it by preceding value argument with instruction:
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 }
$ npm install d
To port it to Browser or any other (non CJS) environment, use your favorite CJS bundler. No favorite yet? Try: Browserify, Webmake or Webpack
Define methods which will be automatically bound to its instances
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);
Define lazy properties, which will be resolved on first access
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
$ npm test
# 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