Randal L. Schwartz - Learning Perl: Making Easy Things Easy and Hard Things Possible

by Randal L. Schwartz , brian d foy , and Tom Phoenix

Copyright 2017 Randal L. Schwartz, brian foy, and Tom Phoenix. All rights reserved.

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• October 2016: Seventh Edition

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978-1-491-95432-4

[LSI]

Welcome to the seventh edition of Learning Perl, updated for Perl 5.24 and its latest features. This book is still mostly good even if you are still using Perl 5.8 (although, its been a long time since it was released; have you thought about upgrading?).

We hope youre reading this preface before you buy the book because theres a historical hiccup that may cause some confusion. Theres another language, Perl 6, that started off as a replacement for Perl 5 but then went out on its own without changing the name. As we write this, Perl 5 is probably the version you want. Its the widely installed and used language that people mean when they say simply Perl. Its the one you want if you dont know why this paragraph is here.

If youre looking for the best way to spend your first 30 to 45 hours with the Perl programming language, youve found it. In the pages that follow, youll find a carefully paced introduction to the language that is the workhorse of the Internet, as well as the language of choice for system administrators, web hackers, and casual programmers around the world. Weve designed this book based on the in-person classes we teach, so weve timed the book for a weeks worth of work.

We cant give you all of Perl in just a few hours. The books that promise that are probably fibbing a bit. Instead, weve carefully selected a useful subset of Perl for you to learn, good for programs from 1 to 128 lines long, which end up being about 90% of the programs in use out there. And when youre ready to go on, you can get Intermediate Perl, which picks up where this book leaves off. Weve also included a number of pointers for further education.

Each chapter is small enough so you can read it in an hour or two. Each chapter ends with a series of exercises to help you practice what youve just learned, with the answers in for your reference. Thus, this book is ideally suited for a classroom Introduction to Perl course. We know this directly because the material for this book was lifted almost word for word from our flagship Learning Perl course, delivered to thousands of students around the world. However, weve designed the book for self-study as well.

Perl lives as the toolbox for Unix, but you dont have to be a Unix guru, or even a Unix user, to read this book. Unless otherwise noted, everything were saying applies equally well to Windows ActivePerl from ActiveState and Strawberry Perl and pretty much every other modern implementation of Perl.

Although you dont need to know a single thing about Perl to begin reading this book, we recommend that you already have familiarity with basic programming concepts such as variables, loops, subroutines, and arrays, and the all-important editing a source code file with your favorite text editor. We dont spend any time trying to explain those concepts. Although were pleased that weve had many reports of people successfully picking up Learning Perl and grasping Perl as their first programming language, of course we cant promise the same results for everyone.