关于codestyle

如果你的代码易于阅读，那么代码中bug也将会很少，因为一些bug可以很容被调试，并且，其他开发者参与你项目时的门槛也会比较低。因此，如果项目中有多人参与，采取一个有共识的编码风格约定非常有必要。

以todomvc的编码要求为例：

General Rules

Tab indentation
Single-quotes
Semicolon
Strict mode
No trailing whitespace
Variables at the top of the scope
Multiple variable statements
Space after keywords and between arguments and operators
Return early
JSHint valid
Consistency

Example:

'use strict';

function foo(bar, fum) {
    var i, l, ret;
    var hello = 'Hello';

    if (!bar) {
        return;
    }

    for (i = 0, l = bar.length; i < l; i++) {
        if (bar[i] === hello) {
            ret += fum(bar[i]);
        }
    }

    return ret;
}

Read idiomatic.js for general JavaScript code style best practices.

Anonymous Functions

When using anonymous functions, leave a space between the function name and opening parenthesis.

Example:

(function () {
    'use strict';

    var thanks = 'mate';
})

Strict mode

Strict mode should be used wherever possible, but must never be globally applied. Instead, use it inside an IIFE as shown above

Comments

Inline comments are a great way of giving new users a better understanding of what you're doing and why.

It's also helpful to let your functions breathe, by leaving additional lines between statements.

Example:

// Ok.
var removeTodo = function (todoItem) {
    var todoModel = todoItem.getModel(); // Grab the model from the todoItem.
    todoItem.find('.destroy').click(); // Trigger a click to remove the element from the <ul>.
    todoModel.remove(); // Removes the todo model from localStorage.
};

// Better.
var removeTodo = function (todoItem) {
    // Grab the model from the todoItem.
    var todoModel = todoItem.getModel();

    // Trigger a click to remove the element from the <ul>.
    todoItem.find('.destroy').click();

    // Removes the todo model from localStorage.
    todoModel.remove();
};

RequireJS

When using RequireJS, please format your code to these specifications:

define('Block', [
    'jQuery',
    'Handlebars'
], function ($, Handlebars) {
    'use strict';

    // Code here.
});

JSHint

When you submit your pull request, one of the first things we will do is run JSHint against your code.

You can help speed the process by running it yourself:

jshint path/to/your/app/js

Your JSHint code blocks must follow this style:

/*global define, App */
/*jshint unused:false */

一些达成共识的JavaScript编码风格约定

http://www.iteye.com/news/28028-JavaScript-code-style-guide