Higher-Order Perl

Most Perl programmers were originally trained as C and Unix programmers, so the Perl programs that they write bear a strong resemblance to C programs. However, Perl incorporates many features that have their roots in other languages such as Lisp. These advanced features are not well understood and are rarely used by most Perl programmers, but they are very powerful. They can automate tasks in everyday programming that are difficult to solve in any other way. One of the most powerful of these techniques is writing functions that manufacture or modify other functions. For example, instead of writing ten similar functions, a programmer can write a general pattern or framework that can then create the functions as needed according to the pattern. For several years Mark Jason Dominus has worked to apply functional programming techniques to Perl. Now Mark brings these flexible programming methods that he has successfully taught in numerous tutorials and training sessions to a wider audience.

• Introduces powerful programming methods — new to most Perl programmers — that were previously the domain of computer scientists
• Gradually builds up confidence by describing techniques of progressive sophistication
• Shows how to improve everyday programs and includes numerous engaging code examples to illustrate the methods

"It's well written...everyone who claims to be an expert ought to read it...these techniques allow programmers to accomplish far more than they're used to." Gregory V. Wilson, Dr. Dobb's Journal

"It is, quite simply, one of the best books on programming I have read for a long time." Martin Schweitzer, Computing Reviews, Association for Computing Machinery

"Mark Jason Dominus has hit his mark with Higher-Order Perl. It is a very informative book that is a must read for Perl programmers who want to take their skills to the next level." Mark Rutz, Linux Journal

The eagerly awaited book by one of the best-known Perl developers summarizing years of innovative practice

Most Perl programmers, including the inventor of Perl, were originally trained as C and UNIX programmers. So the Perl programs that they write bear a strong resemblance to C programs. But Perl incorporates many features that have their roots in non-C programming languages such as LISP. These advanced features are not well understood and are rarely used by most Perl programmers, but they are very powerful. They can automate tasks in everyday programming that are difficult to solve any other way, and also serve as an introduction to the techniques of functional programming for those who have not have come across them in a computer science curriculum. Functional programming is important because it can make code more flexible and reusable. Instead of writing ten similar functions, a programmer can write a general pattern or framework that can then create the functions as needed according to the pattern. So instead of the programmer writing the whole program, the computer does the work. The application of these techniques to Perl has been the work of Mark Jason Dominus for many years. A well-known Perl developer, Mark is the author of several standard Perl modules and was the managing editor of www.perl.com from 1999-2001. He was also a columnist for The Perl Journal for several years and is a frequent speaker and lecturer at numerous Perl conferences and meetings.

Mark Jason Dominus has been programming in Perl professionally since 1992, when he was a UNIX sysadmin with the University of Pennsylvania Department of Computer and Information Sciences.

1. Recursion and Callbacks; 2. Dispatch Tables; 3. Caching and Memoization; 4. Iterators; 5. From Recursion to Iterators; 6. Infinite Streams; 7. Higher-Order Functions and Currying; 8. Parsing; 9. Declarative Programming