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

Using ES5 Strict Mode


A small but precious addition to all the Module Patterns that use IIFEs as their basic building blocks, is the use of Strict Mode for JavaScript execution. This was standardized in the fifth edition of JavaScript, and is an opt-in execution mode with slightly different semantics, in order to prevent some of the common pitfalls of JavaScript, but also having backwards compatibility in mind.

Under this mode, the JavaScript runtime engine will prevent you from accidentally creating a global variable and polluting the Global Namespace. Even in not-so-large applications, it is quite possible that a var declaration before the initial assignment of a variable can be missing, automatically promoting that to a global variable. To prevent this case, strict mode throws an error in case an assignment is issued to an undeclared variable. The following image show the error that is thrown by Firefox and Chrome when a Strict Mode violation happens.

This mode can be enabled by adding...