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Programming in Objective-C
Fourth Edition

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Programming in Objective-C
Fourth Edition
Stephen G. Kochan

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Programming in Objective-C, Fourth Edition
Copyright © 2012 by Pearson Education, Inc. All rights reserved. No part of this book shall bereproduced, stored in a retrieval system, or transmitted by any means, electronic, mechanical, photocopying, recording, or otherwise, without written permission from the publisher. No patent liability is assumed with respect to the use of the information contained herein. Although every precaution has been taken in the preparation of this book, the publisher and author assume no responsibility forerrors or omissions. Nor is any liability assumed for damages resulting from the use of the information contained herein. ISBN-13: 978-0-321-81190-5 ISBN-10: 0-321-81190-9 Library of Congress Cataloging-in-Publication Data Kochan, Stephen G. Programming in objective-c / Stephen G. Kochan. -- 4th ed. p. cm. ISBN 978-0-321-81190-5 (pbk.) 1. Objective-C (Computer program language) 2. Object-orientedprogramming (Computer science) 3. Macintosh (Computer)--Programming. I. Title. QA76.64.K655 2012 005.1'17--dc23 2011046245 Printed in the United States of America Second Printing: March 2012

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❖ To Roy and Ve, two people whom I dearly miss. To Ken Brown, “It’s just a...