Book Image

jQuery Design Patterns

By : Thodoris Greasidis
Book Image

jQuery Design Patterns

By: Thodoris Greasidis

Overview of this book

jQuery is a feature-rich JavaScript library that makes HTML document traversal and manipulation, event handling, animation, and Ajax much simpler with an easy-to-use API that works across a variety of browsers. With a combination of versatility and extensibility, jQuery has changed the way that millions of people write JavaScript. jQuery solves the problems of DOM manipulation, event detection, AJAX calls, element selection and document queries, element attribute and data management, as well as object management utilities. This book addresses these problems and shows you how to make the best of jQuery through the various design patterns available. The book starts off with a refresher to jQuery and will then take you through the different design patterns such as facade, observer, publisher/subscriber, and so on. We will also go into client-side templating techniques and libraries, as well as some plugin development patterns. Finally, we will look into some best practices that you can use to make the best of jQuery.
Table of Contents (18 chapters)
jQuery Design Patterns
Credits
About the Author
About the Reviewer
www.PacktPub.com
Preface
Index

Introducing the concept of Promises


Promises, also known as Futures, are described by Computer Science as specialized objects that are used for synchronization of asynchronous, concurrent, or parallel procedures. They are also used as proxies to propagate the result of a task when its generation completes. This way, a Promise object is like a contract where an operation will eventually complete its execution, and anyone having a reference to this contract can declare their interest to be notified about the result.

Since they were introduced to JavaScript developers, as part of several libraries, they revolutionized the way we use asynchronous functions and compose them in implementation with complex synchronization schemes. This way, web developers can create more flexible, scalable, and readable implementations, making method invocations with callbacks look like a primitive pattern and effectively eliminating the Callback Hell situations.

One of the key concepts of Promises is that asynchronous...