Mark-Jason Dominus is the smartest person in the world, and he wrote a fabulous book.

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Product Description

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

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Product Details

• Amazon Sales Rank: #76754 in Books
• Published on: 2005-03-28
• Original language: English
• Number of items: 1
• Binding: Paperback
• 600 pages

Review
"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, November 2005

"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, July 2005

"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, November 2005



"Higher-Order Perl is one of the Perl books that should have a place on the bookshelf of every Perl programmer. It offers an in-depth understanding of important programming techniques and fundamental concepts. The chapter on parsing alone is worth the price of this book. I do not know a better text about parsing in Perl."
—Reinhard Voglmaier, Unix Review, November 2005



"Higher-Order Perl is the most exciting, most clearly-written, most comprehensive, and most forward-looking programming book I've read in at least ten years. It's your map to the future of programming in any language."
—Sean M. Burke, Leading Programmer, Comprehensive Perl Archive Network (CPAN)

"There are lots of book that teach you new Perl modules or techniques. This book goes beyond that and teaches a new way to think about Perl programming."
—Peter Norvig, Google Inc.



"As a programmer, your bookshelf is probably overflowing with books that did nothing to change the way you program. . . or think about programming.

You're going to need a completely different shelf for this book.

While discussing caching techniques in Chapter 3, Mark Jason Dominus points out how a large enough increase in power can change the fundamental way you think about a technology. And that's precisely what this entire book does for Perl.

It raids the deepest vaults and highest towers of Computer Science, and transforms the many arcane treasures it finds--recursion, iterators, filters, memoization, partitioning, numerical methods, higher-order functions, currying, cutsorting, grammar-based parsing, lazy evaluation, and constraint programming--into powerful and practical tools for real-world programming tasks: file system interactions, HTML processing, database access, web spidering, typesetting, mail processing, home finance, text outlining, and diagram generation.

Along the way it also scatters smaller (but equally invaluable) gems, like the elegant explanation of the difference between 'scope' and 'duration' in Chapter 3, or the careful exploration of how best to return error flags in Chapter 4. It even has practical tips for Perl evangelists.

Dominus presents even the most complex ideas in simple, comprehensible ways, but never compromises on the precision and attention to detail for which he is so widely and justly admired.

His writing is—as always—lucid, eloquent, witty, and compelling.

Aptly named, this truly is a Perl book of a higher order, and essential reading for every serious Perl programmer."
—Damian Conway, Co-designer of Perl 6



"Higher-Order Perl is a terrific book targeted at the advanced Perl programmer with a significant computer science background. The tone, content, and code make Higher-Order Perl memorable; the knowledge, wisdom, and intuition it provides make it a book any Perl programmer should aim to understand and digest in full."."
—Teodor Zlatanov, Programmer, Gold Software Systems

From the Back Cover
"Higher-Order Perl is the most exciting, most clearly-written, most comprehensive, and most forward-looking programming book I've read in at least ten years. It's your map to the future of programming in any language."
—Sean M. Burke, Leading Programmer, Comprehensive Perl Archive Network (CPAN)
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.

About the Author
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. Mark is an occasional contributor to the Perl Core, and is the author of the standard perlreftut man page as well as the Tie::File, Text::Template, and Memoize modules. From 1999-2001, Mark was the managing editor of the www.perl.com website. He was also a columnist for The Perl Journal for several years. All of his articles for TPJ have been reprinted in Computer Science and Perl Programming: Best of the Perl Journal, from O'Reilly and Associates. Mark's other Perl-related articles have appeared in magazines such as Wiredand IEEE Software. Since 1998, Mark has been a professional Perl trainer. In addition to speaking at conferences such as YAPC, the O'Reilly Open Source Conferences, Usenix, and LISA, he has given training courses for large companies and organizations, including Morgan Stanley, IBM, Bristol-Myers Squibb, and the U.S. Air Force. Mark's work on Rx, a Perl regular expression debugger, won the 2001 Larry Wall Award for Practical Utility.

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Customer Reviews

Aptly named
As a programmer, your bookshelf is probably overflowing with books that did nothing to change the way you program...or think about programming.

You're going to need a completely different shelf for this book.

While discussing caching techniques in Chapter 3, Mark Jason Dominus points out how a large enough increase in power can change the fundamental way you think about a technology. And that's precisely what this entire book does for Perl.

It raids the deepest vaults and highest towers of Computer Science, and transforms the many arcane treasures it finds---recursion, iterators, filters, memoization, partitioning, numerical methods, higher-order functions, currying, cutsorting, grammar-based parsing, lazy evaluation, and constraint programming---into powerful and practical tools for real-world programming tasks: file system interactions, HTML processing, database access, web spidering, typesetting, mail processing, home finance, text outlining, and diagram generation.

Along the way it also scatters smaller (but equally invaluable) gems, like the elegant explanation of the difference between 'scope' and 'duration' in Chapter 3, or the careful exploration of how best to return error flags in Chapter 4. It even has practical tips for Perl evangelists.

Dominus presents even the most complex ideas in simple, comprehensible ways, but never compromises on the precision and attention to detail for which he is so widely and justly admired.

His writing is--as always--lucid, eloquent, witty, and compelling.

Aptly named, this truly is a Perl book of a higher order, and essential reading for every serious Perl programmer.

An instant classic
Many in the Perl community have been eagerly awaiting Higher Order Perl, and they will not be dissapointed. Not only is this a great Perl book, it's one of the best general computer science texts I've read in a long time. Dominus focuses on the functional, LISP-like aspects of Perl, breaking readers of the procedural habits they have developed writing Perl code. The book starts with a few simple examples of callbacks and closures, and quickly moves on to developing functions that dynamically manufacture and return other functions. These techniques are used to their fullest potential as Dominus shows us how to use dynamic iterators to eliminate recursion; an invaluable technique considering Perl's lack of tail call optimization. Further techniques include using iterators to transform other iterators (analagous to Perl's map function), currying, using linked lists to create "lazy" streams that produce their data upon request, and function memoization. Dominus also makes digressions into Perl internals, giving the reader a magnificent depth of understanding about how these techniques actually function under the hood.

Lives up to the expectations
In "Higher Order Perl" (or HOP as it's affectionately called in the Perl community), the renown Perl wizard Mark Jason Dominus (MJD) shows how to take Perl coding to the next level by applying advanced programming techniques from the domain of functional programming.

The book covers recursion (including methods to convert recursive code to iterative code), iterators, streams, memoization, currying, parsing, constraint programming and higher order functions (functions that take functions as arguments and/or return other functions). It is packed with great, sophisticated code which is explained very well and is a model for correct programming. The author takes an approach similar to Peter Norvig's PAIP - advanced coding techniques are presented, and then non-trivial programs are written to demonstrate these concepts.

The comparison with Lisp here is unavoidable, and MJD talks about Lisp in his preface. He claims that Perl shares 6 of the "7 features unique to Lisp" quoted from Norvig's PAIP, and that this basically means that most of what can be written in Lisp can be written in Perl in roughly the same manner. But as he himself admits in a later interview, the 7th "missing feature" of Lisp, namely its uniform syntax, is what *really* differentiates Lisp from the rest. Lisp's syntax allows a very clean handling of higher-order functions, list-processing, and most importantly macros. The contrast between MJD's own code in HOP and Norvig's PAIP code is the best example for this fundamental difference. Be MJD's code as clean and nice as it is (for Perl, anyway), it is nowhere near the sheer aesthetic appeal of Norvig's Lisp.

Still, Lisp is Lisp and Perl is Perl, and each has its respectable place in the world of programming. HOP is a great book to read, and I warmly recommend it to any intermediate+ Perl programmer. For people who have never programmed in Lisp or have never learned functional programming techniques, this book is a must - it will literally take your code to a higher level. For diehard fans of Lisp, this book demonstrates how to employ most of your favorite techniques in the most practical language out there (though the Perlish syntactic sugar will at times make your teeth grind).