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This week, the whole PSC was in attendance.

We merged HTTP-Tiny#6, and then discussed a number of topics:

• some improvements on the process for releasing blead-upstream dual-life modules are needed
• the instructions for releasing a new Perl are difficult to follow and partly redundant, the process takes longer than it should, and more of it could be automated
• the pumpkin permission list has grown over time, and probably needs to be trimmed
• more talk about Markdown documentation
• thoughts on how to strike a better balance with the verbosity/brevity of meeting minutes

These are some answers to the Week 284, Task 1, of the Perl Weekly Challenge organized by Mohammad S. Anwar.

Spoiler Alert: This weekly challenge deadline is due in a few days from now (on September 1, 2024, at 23:59). This blog post provides some solutions to this challenge. Please don’t read on if you intend to complete the challenge on your own.

Task 1: Lucky Integer

You are given an array of integers, @ints.

Write a script to find the lucky integer if found otherwise return -1. If there are more than one then return the largest.

A lucky integer is an integer that has a frequency in the array equal to its value.

Example 1

Input: @ints = (2, 2, 3, 4)
Output: 2

Example 2

Input: @ints = (1, 2, 2, 3, 3, 3)
Output: 3

Example 3

Sometimes one needs an extra ounce of performance. Why not combine the high level semantics of Perl with the punch of assembly?

This repo includes various examples of how this can be done.

This block of code is valid Perl:

if (my $var1 = calc1()) {
    say $var1;
} elsif (my $var2 = calc2()) {
    say "$var1, $var2";
}

As you can see, $var1, which is declared in the if clause, is visible inside the elsif clause too.

Perl never ceases to amaze me!

(Also appears in my blog)

These are some answers to the Week 283, Task 2, of the Perl Weekly Challenge organized by Mohammad S. Anwar.

Spoiler Alert: This blog post provides some solutions to this challenge. Please don’t read on if you intend to complete the challenge on your own.

Task 2: Digit Count Value

You are given an array of positive integers, @ints.

Write a script to return true if for every index i in the range 0 <= i < size of array, the digit i occurs exactly the $ints[$i] times in the given array otherwise return false.

Example 1

I remember when one one of my grandchildren helpfully decided reorganise a bookshelf whilst by himself. Upon being discovered, sitting in front of an empty shelf with books strewn all around him, his instinctive reaction made me feel proud to be his grandpa. He looked up and said, “Oh dear! Oh dear! what happened?”, as if this calamity had occurred spontaneously, astonishing him as much as the angry parent who was going to have to tidy it all up. It is hard to hide amusement when you watch your kids have to deal with their kids.

Advanced Disaster Management Strategy for Grandchildren and Programmers

Here I share my personal favourite core enhancements in Perl v5.40.

https://theweeklychallenge.org/blog/what-is-new-in-perl

Just Graham and Philippe this time.

We talked about HTTPS in core, and some ideas about it, while the CPAN Security Group is preparing some proposals. Today was the deadline for releasing 5.41.1, but we don’t have volunteers yet, so Graham said he would do it sometime soon.

We also noted that we’ll need some volunteers for the next 10 or so development releases.

These are some answers to the Week 283, Task 1, of the Perl Weekly Challenge organized by Mohammad S. Anwar.

Spoiler Alert: This weekly challenge deadline is due in a few days from now (on August 25, 2024, at 23:59). This blog post provides some solutions to this challenge. Please don’t read on if you intend to complete the challenge on your own.

Task 1: Unique Number

You are given an array of integers, @ints, where every element appears more than once except one element. ` Write a script to find the one element that appears exactly one time.

Example 1

Input: @ints = (3, 3, 1)
Output: 1

Example 2

Input: @ints = (3, 2, 4, 2, 4)
Output: 3

Example 3

Wir freuen uns, die Veröffentlichung von OTOBO 11 bekannt zu geben! Die neueste Version der beliebten Open-Source-Ticketsystem-Software bringt zahlreiche Verbesserungen und neue Funktionen mit sich. Erfahren Sie mehr über die neuen Features und Änderungen auf OTOBO

Over the years that I have existed in four dimensions, I have come to accept that time is not a linear concept heading inexorably in one direction at a uniform rate. It didn't take an Einstein or Hawking to convince me either. Time is as malleable as the distortions applied by our consciousness, or imposed by those around us. Consider my youngest daughter's essay due to be handed in on Tuesday, a task assigned 4 months earlier. At 4,000 words, it represented roughly 6 words an hour allowing for eating, sleeping, work, weekend fun, and other essential time-devouring activities. Yet the "I have got plennnnty of time, chill, dad!" of a few months ago, has now turned into cries of despair, as she has to do an all nighter at her desk instead of being at some selfie-rich event critical to her mental well-being and social standing.

Graham and Philippe met briefly today.

Now that Perl 5.40 is out, and the nomination process for the next PSC is underway, there wasn’t much to discuss, so we cut the meeting short.

These are some answers to the Week 282, Task 2, of the Perl Weekly Challenge organized by Mohammad S. Anwar.

Spoiler Alert: This weekly challenge deadline is due in a few days from now (on August 18, 2024, at 23:59). This blog post provides some solutions to this challenge. Please don’t read on if you intend to complete the challenge on your own.

Task 2: Changing Keys

You are given an alphabetic string, $str, as typed by user.

Write a script to find the number of times user had to change the key to type the given string. Changing key is defined as using a key different from the last used key. The shift and caps lock keys won’t be counted.

Example 1

The Weekly Challenge 270/2

In the week 270, the second task was really interesting and difficult. Here’s a slightly reformulated version:

We’re given an array of positive integers @ints and two additional integers, $x and $y. We can apply any sequence of the following two operations: 1. Increment one element of @ints. 2. Increment two elements of @ints. The cost of each application of operation 1 is $x, the cost of operation 2 is $y. What’s the minimal cost of a sequence of operations that makes all the elements of @ints equal?

Why do I say it was difficult? I compared all the Perl and Raku solutions I could find in the GitHub repository and none of them gave the same results as mine. It took me several days to find an algorithm that would answer the tricky inputs I generated with a pen and paper, and one more day to optimise it to find the solutions in a reasonable time.

Last year at the Perl Toolchain Summit (PTS) in Lyon, I left three draft pull requests: one about the class declaration introduced in Perl 5.37, one about the PAUSE on docker, and one about multifactor authentication. I wanted to brush them up and ask Andreas König to merge some, but which should I prioritize this year?

Following up on my previous post (MariaDB 10 and Perl DBIx::Class::Schema::Loader), I wanted to try the 'deploy' feature to create database tables from Schema/Result classes.

I was surprised that I could not create a table in the database when a timestamp field had a default of current_time(). The problem was that the generated CREATE TABLE entry placed quotes around 'current_timestamp()' causing an error and rejected entry.

As mentioned in a previous post, I had created file SQL/Translator/Producer/MariDB.pm as part of the effort to get MariaDB 10 clients to work correctly with DBIx::Class::Schema::Loader. Initially it was a clone of the MySQL.pm file with name substitutions. To correct the current_timestamp problem I added a search/replace in the existing create_field subroutine in the MariaDB.pm file to remove the quotes.

These are some answers to the Week 281, Task 1, of the Perl Weekly Challenge organized by Mohammad S. Anwar.

Spoiler Alert: This weekly challenge deadline is due in a few days from now (on August 18, 2024, at 23:59). This blog post provides some solutions to this challenge. Please don’t read on if you intend to complete the challenge on your own.

Task 1: Good Integer

You are given a positive integer, $int, having 3 or more digits.

Write a script to return the Good Integer in the given integer or -1 if none found.

A good integer is exactly three consecutive matching digits.

Example 1

Input: $int = 12344456
Output: "444"

Example 2

Input: $int = 1233334
Output: -1

Example 3

Chapter 3 of Higher Order Perl describes various approaches to memoization of an expensive function: private cache and the Memoize module. The book was written in 2005 (Perl was at version 5.8 back then) , so it does not include another way for function caching that is now available : caching through state variables (introduced in Perl 5.10). The Fibonacci example considered in HOP also requires the ability to initialize state hash variables (available since Perl 5.28). The code below contrasts the implementation with a state variable v.s. the memoize module:

In anticipation for the stable release, we:

• revived the “HTTPS out-of-the-box” project: the CPAN Security Group committed to help us select a workable solution, with a goal of implementing it in time for Perl 5.42
• discussed the minutiae of the next stable release
• decided to do it on 2024-05-24 (Friday)