I’m also noticing a lack of literature on Perl on the command line, I.e “perl -nae <some script>”.
Is awk just better for this use case?
Why Perl gets such a bad rap, then? I'll tell you.
I've used Perl for almost 30 years now, and I've never found any limits in the tool. This means every limit I found was _mine_. Many programmers feel bad when they find their own limits, but it doesn't have to be the case.
You should be OK with finding your own limits, and be willing to overcome them, and strive to become a Perl power user, just like the founder, Larry Wall.
If you choose this, to grow and improve and be better, and better, and better, then Perl is the best option.
It's up to you.
I wonder if AI will make limitless languages easier to work with and maintain.
Limited languages are suitable for those that are willing to manage only so much. That's why Java has no "goto".
But Perl does offer "goto". Why? Because Larry Wall built Perl for himself, and he wanted the most powerful tool that he could conceive. That's exactly what Perl is.
And I accept that, and I really want that. Every time I mess up with Perl, I don't blame my tool. I just laugh out loud and exclaim: "Thanks, Larry, for letting me know another way to not be up to my job".
Perl is the magic wand. If you don't want to be a magician, you don't need it.
But if you want to be a magician, you'll be thrilled to know Perl has three forms of "goto", not just one. This is what the textbook says about the third one: "The goto &NAME form is highly magical and sufficiently removed from the ordinary goto to exempt its users from the opprobium to which goto users are customarily subjected".
sub test() {last unless $_}
for (1, 2, 0, 3) {
print "$_\n";
test;
}
// 1 2 0
I don’t think investing in it is wise when you can invest in something more relevant. Although there’s barely anything that covers the subj as much as Perl, which is a shame on us all. A programming language that requires an import or two to dig through a file is degenerate. Old languages understood well what a programmer needs.
The "creation" part is key. Perl is a tool for "easy creation", for creators that want to be more productive. This is what Larry Wall wanted.
This is why Perl is good for prototyping. You "create" the prototype, and then you "translate" it to something else.
Perl is quite relevant for me, but I say this as a creator.
For example, I can easily imagine something like this:
import 'use-perl'
while (await ls_lr('./*.txt')) {
while (await read_lines($filename)) {
print($ln, $line)
- "Programming is (should be) fun!", by Gerald Jay Sussman. https://m.youtube.com/watch?v=2MYzvQ1v8Ww
- "On Writing", by Stephen King. Just the chapter "Toolbox".
perl is more of a completely replacement for sh+awk for a standalone script/program. it was the first scripting language i know of that could do sockets networking and other complex things you'd previously need to write in c. it has extremely powerful text processing capabilities, like awk. but it's a big complicated, unusual scripting language. if you want a big complex full-featured scripting language to make a complete tool these days, why not use Python? if you only need really fancy text manipulation, maybe Perl, but i don't see that use a lot.
[1] https://www.gnu.org/software/gawk/manual/html_node/index.htm... [2] https://awk.dev/
Ruby is heavily inspired by Perl and lets you do a lot of work with simple one liners embedded in Bash scripts.
It's also great for longer standalone programs and there is a larger community.
Lots of interesting Perl-isms are also doable in Ruby.
I have written a book on Perl one-liners with plenty of examples and exercises [0]. I've also written books on CLI text processing tools like grep, sed, awk and coreutils [1]. If you prefer just solving exercises, check out my interactive TUI apps [2].
>Is awk just better for this use case?
It depends on the kind of tasks you'd need to solve. I generally prefer grep, sed and awk first. Perl helps if I need powerful regexp and other niceties like the huge number of built-in functions and access to third-party libraries.
[0] https://learnbyexample.github.io/learn_perl_oneliners/
[1] https://github.com/learnbyexample/scripting_course#ebooks
Your work is excellent! Thank you, I’ll buy a copy soon.
Searching for 'perl one liners' and the related term 'perl golf' gives many articles and books:
https://www.perl.com/article/perl-one-liners-part-1/
https://www.perl.com/article/perl-one-liners-part-2/
https://catonmat.net/perl-one-liners-explained-part-one
https://catonmat.net/perl-one-liners-explained-part-two
https://catonmat.net/perl-one-liners-explained-part-three
https://catonmat.net/perl-one-liners-explained-part-four
https://catonmat.net/perl-one-liners-explained-part-five
https://catonmat.net/perl-one-liners-explained-part-six
https://catonmat.net/perl-one-liners-explained-part-seven
http://novosial.org/perl/one-liner/
https://www.oreilly.com/library/view/perl-one-liners/9781457...
So you can start by spending 20 minutes to learn awk, and then spend 20 years to learn Perl (and use awk in the mean time)
Perl was inspired by awk, not the other way around. Perl is more general purpose.
that said, i found it gives a lot of 'foot-guns'.
Most of those are for backward compatilibity with earlier versions.
Recommend you place the following at the top of your Perl scripts:
use strict;
use warnings;
The issue with awk is that there are multiple non-interoperable implementations:
https://en.wikipedia.org/wiki/AWK#Versions_and_implementatio...
https://stackoverflow.com/questions/40409632/what-is-the-dif...
This makes awk scripts less portable than other text processing tools.
awk is also not extensible--it can be awkward (heh) to adapt it to some problems and big scripts get difficult to wrangle.
awk is great if your text processing problem is small.
Sometimes small problems grow in which case Perl tends to be a better choice:
https://stackoverflow.com/questions/366980/what-are-the-diff...
People love to hate perl, but there is a reason why it was installed on all Unix and Linux systems by default and was so popular for web servers on the early Internet (e.g. Apache mod_perl https://perl.apache.org/ and perl mason https://www.perl.com/pub/2002/12/11/mason.html/ ).
Perl also popularized regular expressions as a standard component of programming languages so much that "Perl-compatible regular expressions" are probably the most widely-used regex flavor versus POSIX or other regex variants:
AWK has that one covered fair and square, even BusyBox has AWk.
If you want more information about running Perl on the command line then start with https://perldoc.perl.org/perlrun (or `perldoc perlrun` in your shell)
For perl… not sure. I learned a bit of perl in high school and never had a chance to use it, even at work where i occasionally see it being used from other people.
Perl is more powerful but learning and remembering all (or a sufficiently more powerful superset of awk's capabilities) of it is going to take time. The peculiarities of its syntax is certainly not a small set.
All of awk on the other hand needs about 2 hours, if you have done some programming before.
I disagree.
Perl's syntax is easy to learn for anyone who has used C-style syntax as found in C, C++, Java, Javascript, or C#:
https://perldoc.perl.org/perlintro
Perl's syntax is more similar to AWK and C-style languages than Python is.
That said, there is nothing wrong with Python or AWK. They work great and have their places. But it is silly how many people treat Perl like it is impossible to learn or read without ever having used it or seeing where it is used.
I am quite comfortable with C and C++ and still find it hard to hold all of Perl and its operators and naming rules in my head, to keep $s, @, % and .(dot) and quotes etc straight. Granted it makes types more obvious than say Python.
AWK is smaller. There are fewer things to remember.
Perhaps a good comparison would be the size of a Perl pocket guide and a AWK pocket guide. Perl and Python are much bigger subsets of AWK.
In theory Python is the more verbose of these languages. But when I switched from Perl to Python way back when, my short scripts actually got shorter, were quicker and easier to write, and you could actually read them back and understand what they said!
Of course both Perl and Python have changed a lot since I last compared them, so YMMV these days somewhat. I'd be interested to hear from a modern perl-er!
(And: I do still use PCRE libraries sometimes :-P )