Mastering JavaScript High Performance

208 Pages·2015·12.299 MB·English

by  Chad R. Adams

Mastering JavaScript
High Performance
Master the art of building, deploying, and optimizing
faster web applications with JavaScript
Chad R. Adams
BIRMINGHAM - MUMBAI
Mastering JavaScript High Performance
Copyright © 2015 Packt Publishing
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First published: March 2015
Production reference: 1250315
Published by Packt Publishing Ltd.
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ISBN 978-1-78439-729-6
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Credits
Author Project Coordinator
Chad R. Adams Milton Dsouza
Reviewers Proofreaders
Yaroslav Bigus Stephen Copestake
Andrea Chiarelli Paul Hindle
Vishal Rajpal
Indexer
Tejal Soni
Commissioning Editor
Ashwin Nair
Production Coordinator
Melwyn D'sa
Acquisition Editor
Owen Roberts
Cover Work
Melwyn D'sa
Content Development Editor
Parita Khedekar
Technical Editor
Anushree Arun Tendulkar
Copy Editors
Hiral Bhat
Vikrant Phadke
Stuti Srivastava
About the Author
Chad R. Adams is a mobile frontend architect, currently working at Intouch
Solutions, where he looks at creative ways of building HTML5-driven content
and native iOS, Android / Windows Runtime applications. He lives in Raymore,
Missouri, with his wife, Heather, and son, Leo.
In the past, Chad worked as a web developer for large websites, such as MSN.com,
Ford.ca, Xbox.com, WindowsPhone.com, and Copia.com. He also speaks at
developer conferences and groups in the Kansas City area on HTML5 and mobile
development and is the author of Learning Python Data Visualization, Packt Publishing.
You can contact Chad on LinkedIn (http://www.linkedin.com/in/chadradams),
Twitter (@chadradams), or his website (http://chadradams.com).
About the Reviewers
Yaroslav Bigus is an expert in building cross-platform web and mobile
applications. He has over 5 years' experience in development and has worked for
companies in Leeds and New York. He has used the .NET Framework stack to
develop backend systems, JavaScript, AngularJS, jQuery, Underscore for frontends,
and Xamarin for mobile devices.
Yaroslav is working for an Israeli start-up called Tangiblee. He has reviewed Xamarin
Mobile Application Development for iOS, Packt Publishing, written by Paul F. Johnson;
iOS Development with Xamarin CookBook, Packt Publishing, written by Dimitris
Tavlikos; and Learning JavaScript Data Structures and Algorithms, Packt Publishing,
written by Loiane Groner.
I am thankful to my friends and family for their support and love.
Andrea Chiarelli has over 20 years' experience as a software engineer and
technical writer. In his professional career, he has used various technologies for the
projects he was involved in, from C#, JavaScript, and ASP.NET to AngularJS, REST,
and PhoneGap/Cordova.
Andrea has contributed to many online and offline magazines, such as Computer
Programming and ASP Today, and coauthored a few books published by Wrox Press.
Currently, Andrea is a senior software engineer at the Italian office of Apparound,
a mobile software company founded in the heart of Silicon Valley. He is a regular
contributor to http://www.HTML.it, an Italian online magazine focused on web
technologies.
Vishal Rajpal is an experienced software engineer who started developing
professional software applications in 2011. He has worked primarily on Java,
Javascript, and multiplatform mobile application development, including
PhoneGap and Titanium.
Vishal is pursuing his master's degree in computer science from Northeastern
University, Seattle, and has worked on C, Java, and JavaScript. He lives in Seattle and
can be contacted at [email protected]. You can also read more about his
work at https://github.com/vishalrajpal/ and http://www.vishal-rajpal.
blogspot.in.
Vishal has also worked on books by Packt Publishing, such as PhoneGap 3.x Mobile
Application Development HOTSHOT and Learning Javascript, Data Structures,
and Algorithms.
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Table of Contents
Preface v
Chapter 1: The Need for Speed 1
Weren't websites always fast? 1
Getting faster 3
Selecting an effective editor 3
Integrated Development Environments 4
Mid-range editors 8
Lightweight editors 10
Cloud-based editors 12
Summary 15
Chapter 2: Increasing Code Performance with JSLint 17
Checking the JavaScript code performance 17
About the console time API 18
When to use console.time 21
What is JavaScript linting? 22
About JSLint 22
Using JSLint 24
Reviewing errors 26
Configuring messy white space 27
Understanding the use strict statement 30
Using console in JSLint 32
Summary 34
Chapter 3: Understanding JavaScript Build Systems 35
What is a build system? 35
Compiling code by example 36
Error-checking in a JavaScript build system 37
Adding optimization beyond coding standards 38
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