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Beautiful Code by Greg Wilson, Andy Oram

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Beautiful code was conceived by greg wilson in 2006 as a way to elicit insights from leading software developers and computer scientists. Together, he and his co-editor, Andy Oram, approached experts with diverse backgrounds from all over the world. They received a flood of responses, partly because royalties from the book are being donated to Amnesty International. The results of the project appear in this volume.

As wide-ranging as this book is, it represents just a small fraction of what is happening in this most exciting of fields. Thousand of other projects, equally interesting and educational, are being moved forward every day by other programmers whom we did not contact. Furthermore, many excellent practitioners who were asked for chapters do not appear in this book because they were too busy at the time, preferred not to contribute to Amnesty International, or had conflicting obligations. To benefit from the insights of all these people, we hope to do further books along similar lines in the future.

How This Book Is Organized

Chapter 1, A Regular Expression Matcher, by Brian Kernighan, shows how deep insight into a language and a problem can lead to a concise and elegant solution.

Chapter 2, Subversion’s Delta Editor: Interface As Ontology, by Karl Fogel, starts with a well-chosen abstraction and demonstrates its unifying effects on the system’s further development.

Chapter 3, The Most Beautiful Code I Never Wrote, by Jon Bentley, suggests how to measure a procedure without actually executing it.

Chapter 4, Finding Things, by Tim Bray, draws together many strands in Computer Science in an exploration of a problem that is fundamental to many computing tasks.

Chapter 5, Correct, Beautiful, Fast (in That Order): Lessons from Designing XML Verifiers, by Elliotte Rusty Harold, reconciles the often conflicting goals of thoroughness and good performance.

Chapter 6, Framework for Integrated Test: Beauty Through Fragility, by Michael Feathers, presents an example that breaks the rules and achieves its own elegant solution.

Chapter 7, Beautiful Tests, by Alberto Savoia, shows how a broad, creative approach to testing can not only eliminate bugs but turn you into a better programmer.

Chapter 8, On-the-Fly Code Generation for Image Processing, by Charles Petzold, drops down a level to improve performance while maintaining portability.

Chapter 9, Top Down Operator Precedence, by Douglas Crockford, revives an almost forgotten parsing technique and shows its new relevance to the popular JavaScript language.

Chapter 10, The Quest for an Accelerated Population Count, by Henry S. Warren, Jr., reveals the impact that some clever algorithms can have on even a seemingly simple problem.

Chapter 11, Secure Communication: The Technology Of Freedom, by Ashish Gulhati, discusses the directed evolution of a secure messaging application that was designed to make sophisticated but often confusing cryptographic technology intuitively accessible to users.

Chapter 12, Growing Beautiful Code in BioPerl, by Lincoln Stein, shows how the combination of a flexible language and a custom-designed module can make it easy for people with modest programming skills to create powerful visualizations for their data.

Chapter 13, The Design of the Gene Sorter, by Jim Kent, combines simple building blocks to produce a robust and valuable tool for gene researchers.

Chapter 14, How Elegant Code Evolves with Hardware: The Case of Gaussian Elimination, by Jack Dongarra and Piotr Luszczek, surveys the history of LINPACK and related major software packages to show how assumptions must constantly be re-evaluated in the face of new computing architectures.

Chapter 15, The Long-Term Benefits of Beautiful Design, by Adam Kolawa, explains how attention to good design principles many decades ago helped CERN’s widely used mathematical library (the predecessor of LINPACK) stand the test of time.

Chapter 16, The Linux Kernel Driver Model: The Benefits of Working Together, by Greg Kroah-Hartman, explains how many efforts by different collaborators to solve different problems led to the successful evolution of a complex, multithreaded system.

Chapter 17, Another Level of Indirection, by Diomidis Spinellis, shows how the flexibility and maintainability of the FreeBSD kernel is promoted by abstracting operations done in common by many drivers and filesystem modules.

Chapter 18, Python’s Dictionary Implementation: Being All Things to All People, by Andrew Kuchling, explains how a careful design combined with accommodations for a few special cases allows a language feature to support many different uses.

Chapter 19, Multidimensional Iterators in NumPy, by Travis E. Oliphant, takes you through the design steps that succeed in hiding complexity under a simple interface.

Chapter 20, A Highly Reliable Enterprise System for NASA’s Mars Rover Mission, by Ronald Mak, uses industry standards, best practices, and Java technologies to meet the requirements of a NASA expedition where reliability cannot be in doubt.

Chapter 21, ERP5: Designing for Maximum Adaptability, by Rogerio Atem de Carvalho and Rafael Monnerat, shows how a powerful ERP system can be developed with free software tools and a flexible architecture.

Chapter 22, A Spoonful of Sewage, by Bryan Cantrill, lets the reader accompany the author through a hair-raising bug scare and a clever solution that violated expectations.

Chapter 23, Distributed Programming with MapReduce, by Jeff Dean and Sanjay Ghemawat, describes a system that provides an easy-to-use programming abstraction for large-scale distributed data processing at Google that automatically handles many difficult aspects of distributed computation, including automatic parallelization, load balancing, and failure handling.

Chapter 24, Beautiful Concurrency, by Simon Peyton Jones, removes much of the difficulty of parallel programs through Software Transactional Memory, demonstrated here using Haskell.

Chapter 25, Syntactic Abstraction: The syntax-case Expander, by R. Kent Dybvig, shows how macros—a key feature of many languages and systems—can be protected in Scheme from producing erroneous output.

Chapter 26, Labor-Saving Architecture: An Object-Oriented Framework for Networked Software, by William R. Otte and Douglas C. Schmidt, applies a range of standard object-oriented design techniques, such as patterns and frameworks, to distributed logging to keep the system flexible and modular.

Chapter 27, Integrating Business Partners the RESTful Way, by Andrew Patzer, demonstrates a designer’s respect for his programmers by matching the design of a B2B web service to its requirements.

Chapter 28, Beautiful Debugging, by Andreas Zeller, shows how a disciplined approach to validating code can reduce the time it takes to track down errors.

Chapter 29, Treating Code As an Essay, by Yukihiro Matsumoto, lays out some challenging principles that drove his design of the Ruby programming language, and that, by extension, will help produce better software in general.

Chapter 30, When a Button Is All That Connects You to the World, by Arun Mehta, takes you on a tour through the astounding interface design choices involved in a text-editing system that allows people with severe motor disabilities, like Professor Stephen Hawking, to communicate via a computer.

Chapter 31, Emacspeak: The Complete Audio Desktop, by T. V. Raman, shows how Lisp’s advice facility can be used with Emacs to address a general need—generating rich spoken output—that cuts across all aspects of the Emacs environment, without modifying the underlying source code of a large software system.

Chapter 32, Code in Motion, by Laura Wingerd and Christopher Seiwald, lists some simple rules that have unexpectedly strong impacts on programming accuracy.

Chapter 33, Writing Programs for “The Book”, by Brian Hayes, explores the frustrations of solving a seemingly simple problem in computational geometry, and its surprising resolution.

Conventions Used in This Book

The following typographical conventions are used in this book:


Indicates new terms, mathematical variables, URLs, file and directory names, and commands.

Constant width

Indicates elements of program code, the contents of files, and text output displayed on a computer console.

Constant width bold

Shows commands or other text typed literally by the user.

Constant width italic

Shows text replaced with user-supplied values.

Using Code Examples

This book is here to help you get your job done. In general, you may use the code in this book in your programs and documentation. You do not need to contact us for permission unless you’re reproducing a significant portion of the code. For example, writing a program that uses several chunks of code from this book does not require permission. Selling or distributing a CD-ROM of examples from O’Reilly books does require permission.

Answering a question by citing this book and quoting example code does not require permission. Incorporating a significant amount of example code from this book into your product’s documentation does require permission.

We appreciate, but do not require, attribution. An attribution usually includes the title, author, publisher, and ISBN. For example: "Beautiful Code, edited by Andy Oram and Greg Wilson. Copyright 2007 O’Reilly Media, Inc., 978-0-596-51004-6.”

If you feel your use of code examples falls outside fair use or the permission given above, feel free to contact us at .

How to Contact Us

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