On Perl

The sixth edition of this bestselling Perl tutorial includes recent changes to the language. Years of classroom testing and experience helped shape the book's pace and scope, and this edition is packed with exercises that let readers practice the concepts while they follow the text.

Written by one of today's top-selling author's on programming languages, this practical, trailblazing guide to learning Perl offers all the advantages of a reference manual with a detailed, yet concise study on all of the language's key elements, and is not dependent upon either UNIX or Windows. Begins with a complete introduction to Perl: what it is, scripts vs. programs, its central characteristics, and more. Examines scalar types, expressions, and simple input and output; control statements; arrays; hashes and references; functions; pattern matching; files, input/output, and formats; CGI programming with Perl; and other advanced topics. Each chapter includes a summary and numerous exercises. For professionals in the computer science and related fields.

The book has an introductory chapter that gets the reader started quickly with programming in Perl. The initial part of the book discusses Perl expressions, statements, control flow, built-in data types such as arrays and hashes, and complex data structures built using references. On Perl has several chapters covering specialized topics. The chapter on socket-based network programming deals with forking and using fork to write complex interactive client-server programs. There is a chapter with in-depth discussion of CGI programming including error-handling and security issues that arise. The chapter on web-client programming deals with writing programs that access Web pages, fill up GET and POST forms, handle cookies and redirected Web pages. The book has several unique chapters not found in any other book on Perl in the market. The chapter on security discusses hashes such as MD5, message authentication codes (MACs), digital signature schemes, and encryption techniques such as DES, Rijndael, and RSA. Other chapters deal with writing recursive programs that work with files and directories; this chapter also discusses predefined modules that deal with portability in file names and paths across operating systems, recursive traversal of file hierarchies and tarring and untarring of filles. The chapter on functional programming illustrates that Perl functions are first-class, can be used to write closures and can be composed to form more complex functions. In particular, this can be useful for programming in artificial intelligence.

Part of the fun of programming in Perl lies in tackling tedious tasks with short, efficient, and reusable code. Often, the perfect tool is the one-liner, a small but powerful program that fits in one line of code and does one thing really well. In Perl One-Liners, author and impatient hacker Peteris Krumins takes you through more than 100 compelling one-liners that do all sorts of handy things, such as manipulate line spacing, tally column values in a table, and get a list of users on a system. This cookbook of useful, customizable, and fun scripts will even help hone your Perl coding skills, as Krumins dissects the code to give you a deeper understanding of the language. You'll find one-liners that: * Encode, decode, and convert strings * Generate random passwords * Calculate sums, factorials, and the mathematical constants π and e * Add or remove spaces * Number lines in a file * Print lines that match a specific pattern * Check to see if a number is prime with a regular expression * Convert IP address to decimal form * Replace one string with another And many more! Save time and sharpen your coding skills as you learn to conquer those pesky tasks in a few precisely placed keystrokes with Perl One-Liners.

Perl is a powerful programming language that has grown in popularity since it first appeared in 1988. The first edition of this book, Programming Perl, hit the shelves in 1990, and was quickly adopted as the undisputed bible of the language. Since then, Perl has grown with the times, and so has this book.Programming Perl is not just a book about Perl. It is also a unique introduction to the language and its culture, as one might expect only from its authors. Larry Wall is the inventor of Perl, and provides a unique perspective on the evolution of Perl and its future direction. Tom Christiansen was one of the first champions of the language, and lives and breathes the complexities of Perl internals as few other mortals do. Jon Orwant is the editor ofThe Perl Journal, which has brought together the Perl community as a common forum for new developments in Perl.Any Perl book can show the syntax of Perl's functions, but only this one is a comprehensive guide to all the nooks and crannies of the language. Any Perl book can explain typeglobs, pseudohashes, and closures, but only this one shows how they really work. Any Perl book can say that my is faster than local, but only this one explains why. Any Perl book can have a title, but only this book is affectionately known by all Perl programmers as "The Camel."This third edition of Programming Perl has been expanded to cover version 5.6 of this maturing language. New topics include threading, the compiler, Unicode, and other new features that have been added since the previous edition.

A Perl expert can solve a problem in a few lines of well-tested code. Now you can unlock these powers for yourself. Modern Perl teaches you how Perl really works. It's the only book that explains Perl thoroughly, from its philosophical roots to the pragmatic decisions that help you solve real problems--and keep them solved. You'll understand how the language fits together and discover the secrets used by the global Perl community. This beloved guide is now completely updated for Perl 5.22. When you have to solve a problem now, reach for Perl. When you have to solve a problem right, reach for Modern Perl. Discover how to scale your skills from one-liners to asynchronous Unicode-aware web services and everything in between. Modern Perl will take you from novice to proficient Perl hacker. You'll see which features of modern Perl will make you more productive, and which features of this well-loved language are best left in the past. Along the way, you'll take advantage of Perl to write well-tested, clear, maintainable code that evolves with you. Learn how the language works, how to take advantage of the CPAN's immense trove of time-tested solutions, and how to write clear, concise, powerful code that runs everywhere. Specific coverage explains how to use Moose, how to write testable code, and how to deploy and maintain real-world Perl applications. This new edition covers the new features of Perl 5.20 and Perl 5.22, including all the new operators, standard library changes, bug and security fixes, and productivity enhancements. It gives you what you need to use the most up-to-date Perl most effectively, all day, every day. What You Need: Perl 5.16 or newer (Perl 5.20 or 5.22 preferred). Installation/upgrade instructions included.

This book aims to give existing Perl programmers more detailed knowledge of some of the more advanced elements of the language.

Many programmers would love to use Perl for projects that involve heavy lifting, but miss the many traditional algorithms that textbooks teach for other languages. Computer scientists have identified many techniques that a wide range of programs need, such as: Fuzzy pattern matching for text (identify misspellings!) Finding correlations in data Game-playing algorithms Predicting phenomena such as Web traffic Polynomial and spline fitting Using algorithms explained in this book, you too can carry out traditional programming tasks in a high-powered, efficient, easy-to-maintain manner with Perl.This book assumes a basic understanding of Perl syntax and functions, but not necessarily any background in computer science. The authors explain in a readable fashion the reasons for using various classic programming techniques, the kind of applications that use them, and -- most important -- how to code these algorithms in Perl.If you are an amateur programmer, this book will fill you in on the essential algorithms you need to solve problems like an expert. If you have already learned algorithms in other languages, you will be surprised at how much different (and often easier) it is to implement them in Perl. And yes, the book even has the obligatory fractal display program.There have been dozens of books on programming algorithms, some of them excellent, but never before has there been one that uses Perl.The authors include the editor of The Perl Journal and master librarian of CPAN; all are contributors to CPAN and have archived much of the code in this book there."This book was so exciting I lost sleep reading it." Tom Christiansen