Ben Forta - Learning Regular Expressions

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Ben Forta

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Learning Regular Expressions

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Library of Congress Control Number: 2018935165

Copyright 2018 Pearson Education, Inc.

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ISBN-13: 978-0-13-475706-3
ISBN-10: 0-13-475706-8

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Ben Forta is Adobe Systems Senior Director of Education Initiatives. He is also the author of numerous books on SQL, regular expressions, ColdFusion, Windows development, JSP, and more. His book Teach Yourself SQL in 10 Minutes is the best-selling book on SQL of all time.

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Regular expressions and the regular expression language have been around for many years. Regular expression experts have long been armed with an incredibly powerful tool, one that can be used to perform all sorts of powerful text processing and manipulation in just about every language and on every platform.

Thats the good news. The bad news is that for too long, regular expressions have been the exclusive property of only the most tech savvy. Most of us do not fully understand what regular expressions do and what problems they solve. And those who have braved them find regular expression syntax to be unintuitive, and even convoluted at times. Thats sad, because the truth is that regular expressions are nowhere near as complex as they appear to be at first glance. All it takes is a clear understanding of the problem being solved and how to leverage regular expressions so as to solve them.

Part of the problem is the scarcity of quality content on the subject. The few books on regular expressions (and indeed, most of the Web sites boasting regular expression tutorials) tend to concentrate on the syntax, defining what { does and how + differs from *. But that is the easy part; there are not that many special characters in the regular expression language. The tricky part is understanding how they should be used so as to solve real-world problems.

The book you are holding is not intended to be the last word on everything there is to know about regular expressions. If that is what you want, youll need a copy of Jeffrey Friedls Mastering Regular Expressions (OReilly, ISBN 0596528124). Mr. Friedl is the acknowledged regular expressions guru, and his book is the definitive and most comprehensive on the subject. But, and no offense to Mr. Friedl, his book is not for beginnersor even for casual users who just want to get their jobs done without needing to understand the inner workings of regular expression engines. Not that it is not useful informationit is, but not when all you want to do is add validation to your HTML forms or simply perform powerful replace operations on parsed text. If you need to get up and running quickly using regular expressions, youll find yourself torn between having too little information to be productive and having too much information to know where to begin.