JavaScript Patterns 2.10 Naming Conventions

javaScript Patterns 2.10 Naming Conventions

1. Capitalizing Constructors

var adam = new Person();

2. Separating Words

camel case - type the words in lowercase, only capitalizing the first letter in each word.

upper camel case, as in MyConstructor(),

lower camel case, as in myFunction(), calculateArea()and getFirstName()

variable names - first_name, favorite_bands, and old_company_name.

ECMAScript uses camel case for both methods and PRoperties, although the multiword property names are rare (lastIndex and ignoreCase properties of regular expression objects).

3. Other Naming Patterns

Constants - Number.MAX_VALUE

// precious constants, please don't touch

var PI = 3.14,

MAX_WIDTH = 800;

Naming globals with all caps can reinforce the practice of minimizing their number and can make them easily distinguishable.

use an underscore prefix to denote a private method or property.

var person = {    getName: function () {        return this._getFirst() + ' ' + this._getLast();    },    _getFirst: function () {        // ...    },    _getLast: function () {        // ...    }};

Note that JSLint will complain about the underscore prefixes, unless you set the option nomen: false.

Following are some varieties to the _private convention:

• Using a trailing underscore to mean private, as in name_ and getElements_()

• Using one underscore prefix for _protected properties and two for __private properties

• In Firefox some internal properties not technically part of the language are available, and they are named with a two underscores prefix and a two underscore suffix, such as __proto__ and __parent__