Subroutine Signatures in Perl v5.38

Handling of undef / false default values in Perl v5.38
Please checkout the post for more information:
https://theweeklychallenge.org/blog/subroutine-signatures

Create a static mirror of your DEV blog

I started using DEV at the suggestion of Perl Weekly, and I was quite pleased with it - until I discovered that links to dev.to are effectively "shadowbanned" on several major platforms (Reddit, Hacker News, etc.). Posts containing DEV URLs would simply not be shown to users, making it impossible to share content effectively.

To work around this, I thought I would need a way to publish my DEV articles on my own domain so I could freely share them. There are some DEV tutorials out there that explain how to consume the API using frontend frameworks like React, however I don't enjoy frontend at all and I did not want to spend much time on that.

My solution was to get a simple Perl script that builds static versions of the articles, along with an index page. A Perl 5 script will run anywhere, including an old shared linux hosting account I still keep on IONOS, and I really like the speed of static sites.

An introduction to App::ModuleBuildTiny part 2: authoring

Now that we have set up our mbtiny configuration in the previous post, we can actually use it.

Minting a new distribution

Minting a distribution is trivial once you’ve completed the setup. It’s typically just a matter of calling mbtiny mint Foo::Bar. If needed you can override the global configuration at minting time (e.g.  mbtiny mint Foo::Bar --license BSD).

Converting an existing distribution

You can also convert an existing distribution to App::ModuleBuildTiny. In most cases that requires just two things:

Scoping out an even conciser fork idiom

Years ago I wrote about a concise fork idiom. It turns out that it’s possible to do better than everything I discussed in that entry as well as the proposals in the comments.

I didn’t at the time appreciate a clever aspect of variable scoping in Perl:

use strict;
sub get_answer { 0 }
if ( my $answer = get_answer ) {
    ...;
} else {
    print $answer;
}

Random in Perl

Environment variable PERL_RAND_SEED in Perl v5.38
Please checkout the post for more information:
https://theweeklychallenge.org/blog/random-in-perl

This week in PSC (182) | 2025-03-06

All three of us attended, but none of us had the time for significant discussion, so we decided to reclaim the time and make some progress on our various to-do list items.

[P5P posting of this summary]

An introduction to App::ModuleBuildTiny part 1: setting things up

App::ModuleBuildTiny is a relatively new authoring tool. It aims to be a relatively lightweight (at least to some other tools like Dist::Zilla) and newbie friendly tool. It supports two install tools: Module::Build::Tiny (obviously what it was originally designed for) and Dist::Build; it does not support ExtUtils::MakeMaker or Module::Build.

obfuscating Perl for fun and profit

(apologies for "promoting"(?) Perl obfuscation...)

Today I won a gift card at an in-office meeting with the following code. Challenge: print the numbers 1-100 in the most incomprehensible, inefficient way. My entry, edited for brevity:

#!/usr/bin/env perl
use v5.16;
splice @_, @_, -1, ++$_;
splice @_, @_, -1, ++$_;
splice @_, @_, -1, ++$_;
splice @_, @_, -1, ++$_;
splice @_, @_, -1, ++$_;
# plus 95 more of this
say join $/, @_;

Thinking about it more this evening, I came up with

$SIG {__DIE__} = sub { $_ = (pop)+0; chomp; $_%6?say:exit};
{ select undef,undef,undef,1; eval { die time-$^T }; redo; }

(where 6 instead of 101 so I don't have to wait 100 seconds (and to be honest I'm not sure if there'll be rounding errors)).

Wonder if any obfuscators could come up with better (the less inefficient, incomprehensible the better).

Once more unto the Wide character (U+XXXX) in substitution (s///)

I wrote very elliptically about this warning and received some helpful comments with the standard advice about how to proceed when encountering it. Except unfortunately that advice will be of no use when you encounter this warning.

Namely I should have been less cute about it and made it clear that I was specifically talking about a warning about a wide character “in substitution”. How can a s/// even possibly trigger a wide character warning, you ask? Beats me, to be entirely honest, even now, but: if you have a use locale somewhere, it turns out that it can. Because defeating that is what fixed the warning I was getting:

3D Object Scripting using OpenSCAD and Perl

Control. That’s what we all desire and very rarely acquire. The natural restlessness that occurs when you watch one of your offspring flicking from one movie title to the next, barely glancing at the summary before rejecting it, is one of the reasons I don’t like family movie night. My daughter’s grip on the remote is as strong as her decision making skills are weak; I struggle silently to hold back any outburst that would expose my failing parenting abilities once again. I have to distract myself with thoughts of the good old days when the TV had only 4 channels and Teletext was the closest thing to internet. Desiring such regression is now getting much of a habit for me. But we change what we can, accept what we can’t and trust, often foolishly, that those blessed with control do the best for all of us. Ah, look. Another teen fantasy horror romance movie. Thanks a heap, Netflix.

Announce Perl.Wiki.html V 1.24

Herewith V 1.24

Cheers

This week in PSC (181) | 2025-02-26

All three of us attended. Other than administrivia we talked about formally documenting our supported platforms, and we intend to start a discussion on the mailing list about this soon. This is also a topic for the upcoming Perl Toolchain Summit.

[P5P posting of this summary]

Mid-life upgrade for the MailBox suite

In the last months of the previous century, I had to learn Perl to be able to teach it to professionals. It was my 28th language to use, but still took two years to understand deeply. As experienced assembler and C programmer, I was astound how much more of my ideas I could achieve with this new Swiss army knife in my hands. I fell in love with Perl.

Of course, the only way to learn a programming language well, is to use it for a larger project. So, I started to re-code the business shell scripts and websites to Perl. Part of it was sending automated emails to colleagues.

Your phase in life is probably different, but for my personal feeling it was not too long ago; for Internet's lifespan, the year 2000 is ancient history. The first spec for MIME headers in email were just 8 years old at the time, and many email features were still evolving.

Die Hochschule der Bayerischen Wirtschaft unterstützt den Perl Workshop 2025 in München

Die Hochschule der Bayerischen Wirtschaft unterstützt den Perl Workshop 2025 in München.

Wir freuen uns über die Unterstützung durch die HDBW!

Von der bayerischen Wirtschaft, mit der bayerischen Wirtschaft, für die
bayerische Wirtschaft: Die Hochschule der Bayerischen Wirtschaft (HDBW) ist
eine private, staatlich anerkannte Hochschule für angewandte
Wissenschaften - mit Fokus auf Wirtschaft, Technik und Digitalisierung. An der 2012 gegründeten HDBW mit Sitz in
München-Riem studieren derzeit knapp 500 Studierende.

Announcing the Perl Toolchain Summit 2025!

This announcement comes a bit late in the year, but the preparations for the next Perl Toolchain Summit have been going on for several months now. Today I am proud to announce that the 15th Perl Toolchain Summit will be held in Leipzig, Germany, from Thursday May 1st till Sunday May 4th, 2025.

This post is brought to you by Deriv, a Gold Sponsor of the Perl Toolchain Summit 2024.

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Polishing the T-urtle

Cellgraph 0.7 is out. (I introduced it here and there.) And I will tell you about the great new features in the next paragraph and how it helps you to play with logical structures and deepen your understanding of them. But first please let me mention the why!

sqrt.png

CGI::Tiny - Perl CGI, but modern

Originally published at dev.to

In a previous blog post, I explored the modern way to write CGI scripts using frameworks like Mojolicious. But as pointed out in comments, despite the many benefits, there is one critical problem: when you actually need to deploy to a regular CGI server, where the scripts will be loaded each time and not persisted, frameworks designed for persistent applications add lots of overhead to each request.

CGI scripts have historically been written using the CGI module (or even more ancient libraries). But this module is bulky, crufty, and has serious design issues that led to it being removed from Perl core.

When Laziness Isn't

I just needed a few rows of UUIDs in a column of a spreadsheet, more for esthetics than anything else. uuidgen to the rescue.

At the time I didn't realize that uuidgen natively supports outputting multiple ids like so
uuidgen -C 8


The truly lazy path would have been to read the fine uuidgen manual.

Alas, supposing I needed to make multiple calls to uuidgen, I went with a Perl one-liner with a loop, as I couldn't recall the Bash loop syntax.

Here comes the laziness... I I didn't want to write something like this:

perl -e 'print `uuidgen` for @{[1..5]}';


I'm not so found of of perl's de-reference syntax these days, also that array reference/range was giving "the ick" as my kids would say. I needed something lazier, cleaner. I wondered if there were any default/exported arrays available to me that don't have too many elements to them.... Ah, I know!

nicsell supports the German Perl Workshop

Sie bieten, wir catchen!
nicsell ist ein Domain-Backorder-Dienst, auch Dropcatcher genannt, der es Ihnen ermöglicht, auf eine Vielzahl freiwerdender Domains zu bieten, die sich aktuell in der Löschungsphase befinden.
Schon ab einem geringen Startgebot von 10 € können Sie an unseren Auktionen teilnehmen und haben die Chance an Ihre Wunschdomain zu gelangen.
Übrigens: Zur Verstärkung unseres Teams in Osnabrück suchen wir engagierte Perl-Entwickler (m/w/d). Bei Interesse freuen wir uns auf Ihre Bewerbung!

Nicsell

Premium XS Integration, Pt 2

This is a continuation of a series of articles about how to write XS libraries that are more convenient and foolproof for the Perl users, while not blocking them from using the actual C API.

If you spot anything wrong, or want to contribute suggestions, open an issue at the GitHub repo

Wrapping Transient Objects

One frequent and difficult problem you will encounter when writing XS wrappers around a C library is what to do when the C library exposes a struct which the user needs to see, but the lifespan of that struct is controlled by something other than the reference the user is holding onto.

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