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.