Beginning Lua Programming

673 Pages·2007·8.529 MB·English

by  Kurt Jung, Aaron Brown

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Beginning
Lua Programming
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Beginning
Lua Programming
Kurt Jung and Aaron Brown
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Beginning Lua Programming
Published by
Wiley Publishing, Inc.
10475 Crosspoint Boulevard
Indianapolis, IN 46256
www.wiley.com
Copyright © 2007 by Wiley Publishing, Inc., Indianapolis, Indiana
Published simultaneously in Canada
ISBN: 978-0-470-06917-2
Manufactured in the United States of America
10 9 8 7 6 5 4 3 2 1
1MA/SS/QR/QX/IN
Library of Congress Cataloging-in-Publication Data
Jung, Kurt, 1956-
Beginning Lua programming / Kurt Jung and Aaron Brown.
p. cm.
ISBN-13: 978-0-470-06917-2 (pbk.)
ISBN-10: 0-470-06917-1 (pbk.)
1. Lua (Computer program language) I. Brown, Aaron, 1973- II. Title.
QA76.73.L82J96 2007
005.13’3--dc22
2006036460
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respective owners. Wiley Publishing, Inc., is not associated with any product or vendor mentioned in this book.
Lua 5.0 Copyright © 1994-2006, Lua.org, PUC-Rio
Lua 5.1 Copyright © 2006, Lua.org
The Lua logo was designed by Alexandre Nakonechnyj.
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About the Authors
Between his first programs submitted to a Burroughs 5500 on Hollerith punch cards and his latest programs
tapped into a Palm Pilot, Kurt Junghas been the principal programmer on various projects ranging from
airline yield management to state machine–driven workflow.
Aaron Brownbegan programming in elementary school on a Commodore 64. He plays various musical
instruments and speaks Esperanto.
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Credits
Acquisitions Editor Vice President and Executive Publisher
Kit Kemper Joseph B. Wikert
Development Editor Graphics and Production Specialists
Maryann Steinhart Denny Hager
Shane Johnson
Technical Editor Barry Offringa
Adam Dumas Heather Ryan
Production Editor Quality Control Technician
Rachel Meyers John Greenough
Jessica Kramer
Copy Editor
Kathryn Duggan Project Coordinator
Erin Smith
Editorial Manager
Mary Beth Wakefield Proofreading and Indexing
Techbooks
Production Manager
Tim Tate Anniversary Logo Design
Richard Pacifico
Vice President and Executive Group Publisher
Richard Swadley
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Acknowledgments
This project has had strong and capable guidance from Kit Kemper and Maryann Steinhart at Wiley
Publishing. Maryann was remarkably responsive in making sure our questions were answered promptly.
May Kit and Maryann land leading roles when Hollywood makes Beginning Lua Programminginto a
major motion picture.
Laurels and commendations go to Adam Dumas, the best technical editor a book could possibly have.
Adam’s thoroughness and attention to detail uncovered a humbling number of issues with the manuscript,
all of which were brought to our attention in the most courteous and constructive way and often with
insightful corrections.
The Lua community provided much help and many answers. Thanks go to Roberto Ierusalimschy,
Waldemar Celes, and Luiz Henrique de Figueiredo for creating a remarkable language about which
it is easy to remain enthusiastic. Roberto and Luiz Henrique also answered some specific questions
related to this book. The following people were very helpful in answering questions about their respec-
tive projects: André Carregal (LuaForge and the Kepler Project), Mark Hamburg (Adobe Lightroom),
Asko Kauppi (LuaSDLand LuaX), and Kein-Hong Man (ChunkSpy and the No-Frills Introduction to
Lua 5.1 VM Instructions).
From Kurt Jung: Collaborating with an individual as gifted and inventive as Aaron has been an entirely
rewarding experience. It’s with great pleasure that I look forward to future projects together. Multajn
dankojn, mia bonamiko.
The encouragement of my mother and other family members has been greatly appreciated. Although
writing this book may have given me a great excuse to delay various chores (most notably the one
involving a lawn mower) and household repairs, it never interfered with the frequent, pleasurable, and
bonding walks I take with my wife Maura, daughter Laura, and our bundle of canine energy, Brilla.
Iowe the greatest thanks to Maura for her support during this endeavor.
From Aaron Brown: Apart from being my programming mentor, inviting me to collaborate on this book
with him, and being an all-around nice guy, Kurt Jung is one of the few true kindred spirits I have
encountered. Mia teraplano estas plena je angiloj!
Cathy Lewis gave advice on the writing process at a pivotal moment. She (in her capacity as my girlfriend),
my bandmates, and family also deserve thanks for their understanding of my reduced availability while
slaving in the book mines.
Special thanks to Mom (a.k.a. Marty Brown), who bought me that first computer so long ago.