function writeCode(callback) { // do something... callback(); // ... } function introduceBugs() { // ... make bugs } writeCode(introduceBugs); A Callback Example // refactored findNodes() to accept a callback var findNodes = function (callback) { var…

Drawbacks of the namespacing pattern • Reliance on a single global variable to be the application’s global. In the namespacing pattern, there is no way to have two versions of the same application or library run on the same page, because they both ne…

Chaining Pattern - Call methods on an object one after the other without assigning the return values of the previous operations to variables and without having to split your calls on multiple lines. var obj = { value: 1, increment: function () { this…

MYAPP.namespace('MYAPP.utilities.array'); MYAPP.utilities.array = (function () { // dependencies var uobj = MYAPP.utilities.object, ulang = MYAPP.utilities.lang, // private properties array_string = "[object Array]", ops = Object.prototype.toStr…

global namespace object // global object var MYAPP = {}; // constructors MYAPP.Parent = function() { }; MYAPP.Child = function() { }; // a variable MYAPP.some_var = 1; // an object container MYAPP.modules = {}; // nested objects MYAPP.modules.module1…

Principle • Aligning each case with switch(an exception to the curly braces indentation rule). • Indenting the code within each case. • Ending each case with a clear break;. • Avoiding fall-throughs (when you omit the break intentionally). If you're…

JavaScript:回调模式(Callback Pattern) 函数就是对象,所以他们可以作为一个参数传递给其它函数: 当你将introduceBugs()作为一个参数传递给writeCode(),然后在某个时间点,writeCode()有可能执行(调用)introduceBugs(): 这种情况下,introduceBugs()被称为回调函数(callback function)或简称为回调(callback:): function writeCode(callback) { // do…

Gets a length property containing the number of arguments the function expects: function func(a, b, c) {} console.log(func.length); var myFunc = function () { // serialize the arguments object as a JSON string and use that string as a key in your cac…

Scenario You want to use just the methods you like, without inheriting all the other methods that you’ll never need. This is possible with the borrowing methods pattern, which benefits from the function methods  call() and apply(). // call() example…

7.1 Singleton The idea of the singleton pattern is to have only one instance of a specific class. This means that the second time you use the same class to create a new object, you should get the same object that was created the first time. var obj =…