Meyers - More effective C++: 35 new ways to improve your programs and designs

"This is an enlightening book on many aspects of C++: both the regions of the language you seldom visit, and the familiar ones you THOUGHT you understood. Only by understanding deeply how the C++ compiler interprets your code can you hope to write robust software using this language. This book is an invaluable resource for gaining that level of understanding. After reading this book, I feel like I've been through a code review with a master C++ programmer, and picked up many of his most valuable insights."

Fred Wild, Vice President of Technology, Advantage Software Technologies

"This book includes a great collection of important techniques for writing programs that use C++ well. It explains how to design and implement the ideas, and what hidden pitfalls lurk in some obvious alternative designs. It also includes clear explanations of features recently added to C++. Anyone who wants to use these new features will want a copy of this book close at hand for ready reference."

Christopher J. Van Wyk, Professor, Mathematics and Computer Science, Drew University

"Industrial strength C++ at its best. The perfect companion to those who have read Effective C++."

Eric Nagler, C++ Instructor and Author, University of California Santa Cruz Extension

"More Effective C++ is a thorough and valuable follow-up to Scott's first book, Effective C++. I believe that every professional C++ developer should read and commit to memory the tips in both Effective C++ and More Effective C++. I've found that the tips cover poorly understood, yet important and sometimes arcane facets of the language. I strongly recommend this book, along with his first, to developers, testers, and managers ... everyone can benefit from his expert knowledge and excellent presentation."

Steve Burkett, Software Consultant

35 New Ways to Improve Your Programs and Designs

Scott Meyers

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Library of Congress Cataloging-in-Publication Data

Meyers, Scott (Scott Douglas)

More effective C++: 35 new ways to improve your programs and
designs / Scott Meyers.
p. cm.(Addison-Wesley professional computing series)

Includes bibliographical references and index.

ISBN 0-201-63371-X (paperback: alk. paper)

1. C++ (Computer program language) I. Series.

QA76.73.C153M495 1996
005.13'3dc20 9547354

CIP

Copyright 1996 by Addison-Wesley

All rights reserved. Printed in the United States of America. This publication is protected by copyright, and permission must be obtained from the publisher prior to any prohibited reproduction, storage in a retrieval system, or transmission in any form or by any means, electronic, mechanical, photocopying, recording, or likewise. For information regarding permissions, write to:

Pearson Education, Inc
Rights and Contracts Department
501 Boylston Street, Suite 900
Boston, MA 02116
Fax (617) 671-3447

ISBN-13: 978-0-201-63371-9
ISBN-10: 0-201-63371-X

Text printed in the United States on recycled paper at Courier in Stoughton, Massachusetts.

Twenty-fourth printing April 2007

For Clancy,
my favorite enemy within.

A great number of people helped bring this book into existence. Some contributed ideas for technical topics, some helped with the process of producing the book, and some just made life more fun while I was working on it.

When the number of contributors to a book is large, it is not uncommon to dispense with individual acknowledgments in favor of a generic "Contributors to this book are too numerous to mention." I prefer to follow the expansive lead of John L. Hennessy and David A. Patterson in Computer Architecture: A Quantitative Approach (Morgan Kaufmann, first edition 1990). In addition to motivating the comprehensive acknowledgments that follow, their book provides hard data for the 90-10 rule, which I refer to in .

With the exception of direct quotations, all the words in this book are mine. However, many of the ideas I discuss came from others. I have done my best to keep track of who contributed what, but I know I have included information from sources I now fail to recall, foremost among them many posters to the Usenet newsgroups comp.lang.c++ and comp.std.c++.

Many ideas in the C++ community have been developed independently by many people. In what follows, I note only where I was exposed to particular ideas, not necessarily where those ideas originated.

Brian Kernighan suggested the use of macros to approximate the syntax of the new C++ casting operators I describe in .

In , my warning about deleting an array of derived class objects through a base class pointer is based on material in Dan Saks' "Gotchas" talk, which he's given at several conferences and trade shows.

, the proxy class technique for preventing unwanted application of single-argument constructors is based on material in Andrew Koenig's column in the January 1994 C++ Report.

James Kanze made a posting to comp.lang.c++ on implementing postfix increment and decrement operators via the corresponding prefix functions; I use his technique in .

David Cok, writing me about material I covered in Effective C++, brought to my attention the distinction between operator new and the new operator that is the crux of . Even after reading his letter, I didn't really understand the distinction, but without his initial prodding, I probably still wouldn't.

The notion of using destructors to prevent resource leaks (used in ) comes from section 15.3 of Margaret A. Ellis' and Bjarne Stroustrup's The Annotated C++ Reference Manual (see page 285). There the technique is called resource acquisition is initialization. Tom Cargill suggested I shift the focus of the approach from resource acquisition to resource release.

Some of my discussion in was inspired by material in Chapter 4 of