Dan Maharry - TypeScript revealed

TypeScript Revealed

Dan Maharry

TypeScript Revealed

Copyright 2013 by Dan Maharry

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ISBN-13 (pbk): 978-1-4302-5725-7

ISBN-13 (electronic): 978-1-4302-5726-4

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President and Publisher: Paul Manning

Lead Editor: Jonathan Hassell

Technical Reviewer: Todd Meister

Editorial Board: Steve Anglin, Mark Beckner, Ewan Buckingham, Gary Cornell, Louise Corrigan, Morgan Ertel, Jonathan Gennick, Jonathan Hassell, Robert Hutchinson, Michelle Lowman, James Markham, Matthew Moodie, Jeff Olson, Jeffrey Pepper, Douglas Pundick, Ben Renow-Clarke, Dominic Shakeshaft, Gwenan Spearing, Matt Wade, Tom Welsh

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For Jane and Evie, who make me smile and laugh

Contents at a Glance

Contents

About the Author

Dan Maharry is an experienced technical author with over a dozen books to his name and many more as technical reviewer and editor for a variety of publishers including Wrox Press, Apress, Microsoft Press, and OReilly Media.

Dan contributes code and documentation to various open source projects and tries to blog and to speak from time to time to user groups about cool stuff.

Hes also a .NET developer with past stints for the dotCoop TLD registry and various web development houses under his belt.

He listens to a lot of new music as he does the above.

You can find him online at http://hmobius.com . His blog is available at http://blog.hmobius.com .

About the Technical Reviewer

Todd Meister has been working in the IT industry for more than 15 years. Hes been a technical editor for over 75 titles, ranging from SQL Server to the .NET Framework. Besides technical editing, he is the senior IT architect at Ball State University in Muncie, Indiana. He lives in central Indiana with his wife, Kimberly, and their five excellent children.

Acknowledgments

Many thanks to Jon and Mark at Apress for inviting me to write this book, and thanks also to Anders and the TypeScript team for making the fruits of Project Strada available for us to consume.

And, of course, thanks to the two ladies in my life who keep me sane and drag me away from the screen into reality. To Jane and Evie, I love you both.

Introduction

Anders Hejlsberg has a lot to answer for. Perhaps not as well known as Bjarne Stroustrup (C++) or Dennis Ritchie (C), hes responsible for the creation of Turbo Pascal, Delphi, J++, and C#. And, as the creator of the language that the majority of .NET developers have been using for the past ten years, it is fair to say that he knows a fair bit about language design.

October 1, 2012 heralded the start of the journey for another Hejlsberg creation. TypeScript is a superset of JavaScript that brings to it an additional object-oriented-like syntax familiar to .NET programmers that compiles down into JavaScript that any browser can run today. As I write this three weeks since its announcement, its interesting to see how, with hindsight, the loudest reactions have been, Why do we need this? or Not in my backyard, and so onthe naysayers getting their dimes worth before this Friday, when Windows 8 is officially launched and they can copy and paste the same reactions back into their slightly revised pieces about the new touch interface that isnt called Metro. Now that the dust has settled, my personal favorite response to all the initial negativity was simply, But this is Anders.