TypeScript Design Patterns

Vilic Vane

• Éditeur: Packt Publishing
• Année: 2016
• ISBN:
  9781785280832
• Édition: 1
• Sujet: Computer Science
• Sous-sujet: Programming

Boost your development efficiency by learning about design patterns in TypeScript

About This Book

• This step-by-step guide will would demonstrate all the important design patterns in practice
• This book is the only documentation on the market focusing on design patterns in TypeScript
• This book is packed with rich examples that will improve your efficiency and encourage code reuse

Who This Book Is For

If you are a TypeScript developer, this book is for you. No knowledge of design patterns is required to read this book.

What You Will Learn

• Understand the challenges and implications of developing an enterprise application
• Install and configure the necessary tools in order to start developing an application
• Identify the challenges when developing an application
• Apply GoF patterns in an application with a testing approach
• Use and utilize design patterns while developing a TypeScript application or during JavaScript application development
• Reference to SOLID principles and what their benefits do to your projects
• Apply various principles in a TypeScript application
• Improve code quality and development speed

In Detail

In programming, there are several problems that occur frequently. To solve these problems, there are various repeatable solutions that are known as design patterns. Design patterns are a great way to improve the efficiency of your programs and improve your productivity.

This book is a collection of the most important patterns you need to improve your applications' performance and your productivity. The journey starts by explaining the current challenges when designing and developing an application and how you can solve these challenges by applying the correct design pattern and best practices.

Each pattern is accompanied with rich examples that demonstrate the power of patterns for a range of tasks, from building an application to code testing. We'll introduce low-level programming concepts to help you write TypeScript code, as well as work with software architecture, best practices, and design aspects.

Style and approach

In this book, design patterns are explained in a step-by-step manner. All the major patterns covered will improve your understanding of TypeScript and the patterns associated with TypeScript.

TypeScript Design Patterns

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TypeScript Design Patterns

Copyright © 2016 Packt Publishing

All rights reserved. No part of this book may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, without the prior written permission of the publisher, except in the case of brief quotations embedded in critical articles or reviews.

Every effort has been made in the preparation of this book to ensure the accuracy of the information presented. However, the information contained in this book is sold without warranty, either express or implied. Neither the author, nor Packt Publishing, and its dealers and distributors will be held liable for any damages caused or alleged to be caused directly or indirectly by this book.

Packt Publishing has endeavored to provide trademark information about all of the companies and products mentioned in this book by the appropriate use of capitals. However, Packt Publishing cannot guarantee the accuracy of this information.

First published: August 2016

Production reference: 1240816

Published by Packt Publishing Ltd.

Livery Place

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Birmingham

B3 2PB, UK.

ISBN 978-1-78528-083-2

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Credits

Author Vilic Vane	Copy Editor Safis Editing
Reviewer Wander Wang	Project Coordinator Suzanne Coutinho
Commissioning Editor Kunal Parikh	Proofreader Safis Editing
Acquisition Editor Denim Pinto	Indexer Rekha Nair
Content Development Editor Nikhil Borkar	Graphics Jason Monteiro
Technical Editor Hussain Kanchwala	Production Coordinator Aparna Bhagat

About the Author

Vilic Vane is a JavaScript engineer with over 8 years of experience in web development. He started following the TypeScript project since it went public, and he’s also a contributor of the project. He is now working at Ruff, a startup company building an IoT platform that runs JavaScript on embedded devices.

I want to thank the editors and reviewers, including Wander Wang, for their efforts that made this book possible. I also want to thank my girlfriend, Emi, for not pissing me off when she came for me from her school 1,400 km away but could only have a takeout with me in my apartment due to my always-about-to-start-writing condition.

About the Reviewer

Wander Wang is working at Egret Technology Co., Ltd. as the chief architect of Egret Engine. He also works as a part-time teacher in the School of Software Engineering at Beijing University of Technology. Wang has 7 years of experience in developing web and mobile games, and he currently focuses on the language research and extension of TypeScript. Egret Engine is a popular HTML5 game engine written in TypeScript. There are more than 80,000 developers worldwide who build their web or mobile games on the top of Egret Engine. Wang is also interested in technologies such as React, React-Native, and Electron, and so on.

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Preface

It wasn’t a long time ago that many JavaScript engineers or, most of the time, web frontend engineers, were still focusing on solving detailed technical issues, such as how to lay out specific content cross-browsers and how to send requests cross-domains.

At that time, a good web frontend engineer was usually expected to have notable experience on how detailed features can be implemented with existing APIs. Only a few people cared about how to write application-scale JavaScript because the interaction on a web page was really simple and no one wrote ASP in JavaScript.

However, the situation has changed tremendously. JavaScript has become the only language that runs everywhere, cross-platform and cross-device. In the main battlefield, interactions on the Web become more and more complex, and people are moving business logic from the backend to the frontend. With the growth of the Node.js community, JavaScript is playing a more and more important roles in our life.

I am currently working for an IoT company called Ruff that builds a platform for JavaScript to write applications run on embedded devices. You might have seen a fake book cover in the title of Writing Device Drivers in JavaScript, but that is actually a part of what we do.

The boom of JavaScript, however, makes people realize that the language itself might not be powerful enough for applications on a larger scale. While we enjoy the flexibility of the language, we suffer from its lack of static-type information; for instance, consider the following:

• No static type checking: We have to rely on debugging or tests to get rid of simple errors that could be eliminated when the code is written.
• Refactoring is a pain: Basically, what the IDEs or editors can do about JavaScript code is renaming local variables or exported module functions at best.
• Understanding code is difficult: When you grasp a piece of code, you might have to look around and manually search for references just to figure out which properties an object has and what types of property they are. This happens to our own code as well.

Compared to tools such as ESLint and even Flow, which only partially solve the problems, TypeScript does a really good job while it is still sticking to the ECMAScript standard.

TypeScript is indeed an awesome tool for JavaScript. Unfortunately, intelligence is still required to write actually robust, maintainable, and reusable code. But wait, doesn’t the intelligence part involve the true value of our work?

We might all have had trouble finding clues to mysterious bugs, or squeezed our head thinking about how we can add new features to the existing code base. Some of us, with experience and intuition built over the years, may directly come up with a design that’s not bad. For these people, getting through the common design patterns can help gain knowledge of what people have already catalogued over years in the industry or be better understood when discussing software designs with others. For people who have less experience, learning common design patterns may be a more straightforward approach to creating code that’s beautifully designed.

What this book covers

Chap...