Learning Perl/Tk

After a bit of a hiatus, Jason Bennett has returned with a review of Nancy Walsh's Learning Perl/Tk. As the title of the book would indicate, this is an ideal book for those looking to learn the Tk tool kit and Perl. This book assumes a level Perl background, and a little GUI, but is a good intermediate step-click below if you want to know more. Learning Perl/Tk author Nancy Walsh pages publisher O'Reilly rating 8/10 reviewer Jason Bennett ISBN 1-56592-314-6 summary A solid introduction to using the Tk toolkit with Perl. If you have a reasonable Perl background, and a little GUI on the side, you'll pick it up in no time. Background

Greetings, all. This will be the first in a series of reviews dealing with some Tcl/Tk books I've recently acquired. Since I already have some Perl in my background, I took this one first, both to sharpen my Perl skills, and to find out what this Tk thing is all about. Given that my GUI experience is limited to Smalltalk and Java, Tk is quite easy to use. With Smalltalk, I was too busy wrapping myself around OO theory to enjoy the interface, and Java always seemed to make GUI stuff more difficult than it needed to be (although I still love it). Perl and Tk are strong partners, because they share a philosophy of getting things done without a lot of fuss. Perl and Tk are excellent replacements for any GUI scripting language you might use (read: VB). Read on to see how to jump in!

What's the book about?

This is another book in O'Reilly's Learning series (of which Learning Perl really saved my butt in college), which is dedicated to teaching the fundamentals of a certain topic. I want to compare this series with the Learn XY in 21 days type of books, although I believe that would generally be an insult to the quality of O'Reilly. Once you finish this book, you will have enough of an understanding of Tk to be able to do most small projects. You will know most widgets (although I'll admit my own knowledge is limited here), and will generally be prepared to be productive with Tk in Perl.

What's Good?

In order for you to be able to evaluate the usefulness of this book, it will probably help to understand where I'm coming from. I have a BSCS from Georgia Tech, and have enough languages under my belt to do some damage (Lisp is cool!). In fact, I learned Perl originally for a networking project using Learning Perl. It gave me enough to do what was needed. Having said that, I don't live to program, and in fact I'm not big on reading language books. I don't know every language under the sun, and I don't necessarily learn them with the greatest of ease. In other words, my results should be duplicable by most programmers. The most important thing when reading this book is to know Perl (at least have written some stuff in it), and probably have an idea of what to expect when writing GUI code.

Going into this, my Perl was definitely rusty (having not touched it in a while). I didn't have any trouble diving straight in, however. The Perl constructs used are not overly complicated, and my knowledge was sufficient. (NOTE: make sure you have a very recent version of Perl installed. My Redhat 5.2 needed to be upgraded to m4 before the examples would work. Also, get the errata from O'Reilly.) The early chapters deal with basic constructs and widgets, and spend a great deal of time on the geometry managers (go figure). Each chapter introduces a new widget, although some are used before they are introduced (just nod and smile when you see those and don't worry). There are plenty of examples, code fragments, and exercises to keep anyone busy. I tried to work as many as I could, to get a feel for the language, and generally felt like they were helpful. I never felt completely lost or confused, and generally followed things without much trouble. Having finished the book, I feel confident that, given a little work on my Perl, I could write a useful application with Tk, especially given some research on CPAN for various contributed modules. For me, the book worked.

What's Bad?

Nothing in this book is particularly bad, although there are a few nits I'd like to pick. First, the early emphasis on geometry was somewhat interesting. I'm not sure why I care about grid vs pack when I can barely create a button to put on the screen. For that matter, frames are referenced in a short chapter late in the book, after being used all throughout. If the concept is so basic, why not put it toward the beginning? Also, there were times when the author mentions that an option is esoteric, or generally unused, and then spends much more time than necessary on that point. If it's so esoteric, why is it being covered in a basic book like this one? Finally, there were a few times that the book did not explain a point well enough to me, and I had to divine the answer down the road (like configuring scrollbars). It was not a major issue, but there were some things that could have been clearer.

What's In It For Us?

If you want to learn Tk using Perl, this book will let you do that. It gives a solid introduction to the topic, and on completion, you will be a useful Perl/Tk programmer. Just know your Perl going in, and you will be fine.

Purchase the book over at Computer Literacy.

1. Preface
   
2. Introduction to Perl/Tk
3. Geometry Management
4. The Basic Button
5. Checkbuttons and Radiobuttons
6. Label and Entry Widgets
7. Scrollbars
8. The Listbox Widget
9. The Text Widget
10. The Canvas Widget
11. The Scale Widget
12. Menus
13. Frames
14. Toplevel Widgets
15. Binding Events
16. Composite Widgets
17. Methods for Any Widget

1. Configuring Widgets with configure and cget
2. Operating System Differences
3. Fonts
   Index

Comments

Tcl and Perl

[LizardKing]

Tcl has always struck me as a little less anarchic
than Perl. The KDE to Perl's Gnome if you're
into weird analogies.

With version 8, Tcl/Tk really came of age, and I
have actually found myself questioning my
otherwise firm devotion to Perl. Especially when
I encountered oodles of memory leaks in the Perl
Tk module.


Chris Wareham