Ruling the world with Perl and Excel

In Chapter 12 of Learning Perl, we have an exercise for people to practice using the file test operators. Our answer, which can only use the stuff we’ve covered in the book to that point, is simple: » Read more…

The vertical tab now matches \s

Perl 5.18 added vertical tab (or LINE TABULATION in the UCS) to the characters that match the \s character class shortcut. It’s the one exception that made that shortcut different from the POSIX definition of whitespace. For the details, see my posts in The Effective Perler: The vertical tab is part of \s in Perl 5.18. » Read more…

Why we teach the subroutine ampersand

In Learning Perl, we tell readers to use the & to prefix subroutine calls when we introduce the idea of reusable code. This doesn’t sit well with some programmers because it’s not how the experienced programmers work. The & does some magic, which we don’t mention in the book, and it’s a bit crufty for the Perl 5 programmer. » Read more…

“at least two or three hours per week”

Randal Schwartz, in his interview with Leo Laporte and Chris DiBona on FLOSS #9 (way before Randal was ever the host of the same show), says around the 9:20 mark that “Perl is meant for people who use the language at least two or three hours per week”.

This remark was highlighted by John D. Cook in Three-hour-a-week language. I found an even better thought in the comments. rdm says it’s more about knowing what to look for:

I have enough of a perl vocabulary that I know how to perform relevant searches when I am reaching for a concept. Python? Not so much…

That doesn’t have much to do with the language, really. If you spend a couple of hours each week using a language, reading the docs, and looking for answers, you gain experience and knowledge about the process making it slightly easier the next time. I’m not a great programmer, but I’m a pretty good answer finder. That can make up for a lack of talent.

In my Learning Perl classes, I tell people they aren’t going to learn Perl in a week. I can make them aware of things, but they need to practice. Even though we do exercises in the class, thinking about Perl all day for four days can melt anyone’s brain. Take that three (or more) hours a week for half a year and you’ll probably get passably good.

I got used to Perl by doing it almost every day all day for two years, but then I had to relearn it when Randal trained me to be a Perl trainer. I actually learned more by answering the random questions that people had. That was either students in classes or conversations on usenet. Now that could be Stackoverflow. You create some common set of problems for yourself, but by reading the problems from many people, you get to learn things from problems you wouldn’t make yourself. That’s where the gold is.

Advice to a new Perl user

A Learning Perl reader asked me for some advice in private email. After I typed it out I felt like posting it for everyone. He graciously let me use his questions and my answers.


1. I wish to use Perl on Windows, is it a good combination (from a career perspective)?

Although Windows can be a pain, and not just because of Perl, there are plenty of people who need to get things done on Windows. With the Win32:: modules, you can hook into the same APIs. I think you can even use Perl from Powershell.

2. Would the knowledge I’ll gain after self-training for Perl be useful for a long time?

You always have to keep learning. Perl is just a language and you can get almost anything done with it, but the more valuable thing is knowledge about the problem you’re trying to solve.

“Useful” is a harder thing to judge because it mostly depends on what you are doing. Perl can do quite a bit, but I find that “useful” is related to what non-Perl libraries I can access through Perl.

I don’t think you can go wrong at least learning Perl and practicing it for a couple of years. Some of the experience you gain there you can transfer to another language. It’s same the other way around, too, since the more experience you have as a programmer the easier new languages should be for you.

3. How does one figure out a niche for himself in this hugely spread-out world of Perl?

I find something that’s not getting done and take ownership of it. Something out there is being neglected. Just keep plugging away at something boring and unexciting. Running a local user group is good for that.

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