blogs.perl.org

These are some answers to the Week 265, 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 April 21, 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: 33% Appearance

You are given an array of integers, @ints.

Write a script to find an integer in the given array that appeared 33% or more. If more than one found, return the smallest. If none found then return undef.

Example 1

This week, we discussed several topics:

• collecting bugfixes to put in a 5.38.1 maintenance release
• Module::CoreList automated releases, and how we might get them created — what PAUSE user, etc…
• once the PPC for meta:: officially exists, it would be worth having a release on CPAN, to experiment with
• the PPC process still needs some refinement and further clarification on what gets done, when, and by whom

Next Generation Sequencing (NGS) has really taken off the last few years, as both devices and the cost of experiments have dramatically declined. NGS decipher the identity (base composition, the sequence of letters in the alphabet of DNA and RNA) of nucleic acids and return the results in the fastq open data format. Fastq files are flat text files with a standardized layout: each molecule present in the sample that is captured by the sequencer is represented with four fields:

1. a '@' character and is followed by a sequence identifier and an optional description


2. one (typically) or more lines of characters in the four letter alphabet of nucleic acids


3. a metadata field starting with the "+" optionally followed by the same sequence identifier and description as in the first field


4. one, or more lines of the quality of each symbol sequence reported in field 2
   

Hi everybody! I'm finally back with another PWC/TWC blog post for week 230.

Separate Digits

For the first challenge we want to split all the numbers in the array into single digits. Here's the code:

use v5.36;
my @nums;
push(@nums, split(//, $_)) for @ARGV;
say $_ for @nums;

It very simply splits anything in its arguments into individual characters and pushes them onto a new array.

Count Words

Our second challenge asks us to count the words that start with the given prefix. Here's a 4-liner (minus boilerplate) to help us out with this one:

These are some answers to the Week 264, 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 April 14, 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: Target Array

You are given two arrays of integers, @source and @indices. The @indices can only contains integers 0 <= i < size of @source.

Write a script to create target array by insert at index $indices[i] the value $source[i].

Example 1

At the recent YAPC::EU (still running) I gave a talk about my latest CPAN module: Graphics::Toolkit::Color (in short GTC - v1.53). It went a little out of hand and even worse: some of the key thoughts I did not formulate as clear as wanted. That is why I use this channel to correct that. In this first part I outline the goal of the module and the next part will be about the design principles of the public API, moving than into implementation details and the general issues when dealing with colors.

Resource::Silo is a declarative lazy resource container library for Perl. It allows to declare resources such as configuration files, database connections, external service endpoints, and so on, in one place; acquire them on demand; cache them; and release in due order.

It may also be described as the single source of truth for the application's side effects.

For those unfamiliar with Bread::Board:

Hey, hey, hey, hey! A shiny new solution just arrived!

• declare all of your application's resources / dependencies in one place using a simple DSL;
• instantiate them on demand and only once, with little overhead;
• override them with mocks in your tests & guard against unexpected side effects;
• gain more fine-grained control via the ctl frontend.

For Bread::Board users:

Today was PSC 111 — what happened to 110 you ask? Well, it was a bit of a non-meeting a few weeks ago. Nothing to say about it, sorry!

This week, we:

• Said hello to Graham and goodbye to Rik
• We did a bunch of handover, making sure we set up a new Zoom meeting and calendar, and talking about our usual order of business

In more normal business, we:

• talked about the future of use vX, especially related to builtin:: stuff — do we want “use v5.40” to import “builtin::refaddr” for example
• talked about what we’re going to do with the UNIVERSAL::import changes so we can move it forward toward someday making it fatal but without breaking half of CPAN at once

These are some answers to the Week 264, 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 April 14, 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: Greatest English Letter

You are given a string, $str, made up of only alphabetic characters [a..zA..Z].

Write a script to return the greatest english letter in the given string.

A letter is greatest if it occurs as lower and upper case. Also letter ‘b’ is greater than ‘a’ if ‘b’ appears after ‘a’ in the English alphabet.

Example 1

Dear all,

we've got a new release out. Update is highly recommended as it fixes 9 critical security related bugs, i.e.

• CVE-202: 3-33756: SpreadSheetPlugin's EVAL feature exposes information about paths and files on the server
• CVE-2023-24698: Local file inclusion vulnerability in viewfile

Read more about it at https://blog.foswiki.org/Blog/Foswiki218IsReleased

Regards,
Michael.

Once again I'm writing about a TPRC talk instead of a weekly challenge project, but that's because I feel it's a very important topic to be aware of both inside and outside our community as Perl programmers. Sawyer X gave a really great talk about the abuse he personally experienced as a member of the Perl community. I've never experienced abuse in this or any other technology community, but I have experienced abuse before in other contexts. Also, as a disclaimer, although I'm sure many have seen some of Sawyer's situation play out in public, I haven't, as I believe it happened during my extended break from Perl and development in general.

I was seeing this so much talk about smartmatch or given/when, I decided to experiment with a prototype powered pseudo structure I'd been thinking about. The results were pleasing to me, and I plan on releasing this soon. I could rename it to match/case (versus fu/on), but the huffman in me likes the short (and semi-ambiguous) "keywords". Let me know what you think in the comments below.

I still need to do more unit tests, POD, dist.ini, etc. But it's the closest I could get what I was observing on P5P. And the current implementation is about as fast and tight as I think it could be. I also enjoy using Perl's datatype coercion capabilities via prototypes* quite a bit. It is a very powerful, underutilized, and misunderstood capability that can be used to bring about a lot more ideas via a "keyword" experience (which is the entire point).

https://github.com/oodler577/p5-Dispatch-Fu

DESCRIPTION

These are some answers to the Week 263, 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 April 7, 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: Merge Items

You are given two 2-D array of positive integers, $items1 and $items2 where element is pair of (item_id, item_quantity).

Write a script to return the merged items.

Example 1

I've been programming in Perl for almost two decades now. A lot has changed in Perl, and also in the way I program with it.

Several years ago my partners and I started a software company, I was in charge of everything to do with tech, so as CTO it was my responsibility to choose the tech stack our company was going to use. And it was an easy one: Perl.

Years have gone by, our company has continued to grow, our product catalogue has increased and the amount of data processing and analysis we do it's exponentially higher than when we started. And Perl has continued to show what a great option it is.

I would like to list some of the reasons why Perl has been such a great fit for our company.

Versatility

I normally only write about the Perl Weekly Challenge/The Weekly Challenge, but today I have a couple things to say about recent Perl versions. I've been watching the videos from TPRC2023, and loving the talk by Paul Evans What's New in Perl v5.38. I like to have a minimum version in my code generally that I can rely on having all the features from. I think I previously ignored v5.36 because it wasn't in Debian yet (and I typically only use packaged Perl), but thanks to Paul's talk I've really enjoyed looking at the perldelta, where some really groundbreaking Modern Perl changes were made just in the use v5.36 syntax.

Well, now two things have happened. v5.36 is the oldest release still officially supported by the Perl team, and it's in Debian stable. This makes it a great candidate to be my new target version for most code!

Unfortunately, Ubuntu 22.04 (one of my servers) is still stuck on v5.34, and this makes me sad. 😥

In related news, the new object system in v5.38 and beyond looks pretty sweet! I'm excited. Can't wait to see what else gets implemented in the next couple versions.

A little over ten years ago, when Perl 5.18 was approaching its release date, I released match::simple. This was mostly in response to the smartmatch operator (~~) being deprecated, but also a solution to the incredibly arcane rules for how the smartmatch operator operated.

match::simple was intended to be... simpler. The operator looks a little funky because it uses some clever trickery to fake being an infix operator:

    use match::simple;
    
    if ( $this |M| $that ) {
        ...;
    }

These are some answers to the Week 263, 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 April 7, 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: Target Index

You are given an array of integers, @ints and a target element $k.

Write a script to return the list of indices in the sorted array where the element is same as the given target element.

Example 1

Input: @ints = (1, 5, 3, 2, 4, 2), $k = 2
Output: (1, 2)

Sorted array: (1, 2, 2, 3, 4, 5)
Target indices: (1, 2) as $ints[1] = 2 and $k[2] = 2

Example 2

This week, we talked about:

• the recent quietness of the perl5-porters list
• PPC 0013 and the use of a lexical feature (join_with_concat) to enable concat magic
• inclusion of stringify (OP_STRINGIFY) and numify functions in the builtin namespace
• turning the UNIVERSAL::import deprecation warning into a regular warning so as not to imply a removal timescale

The Perl and Raku Conference 2023

The Perl and raku Conference 2023 in Toronto was an event I was really looking forward to. A chance to rub shoulders with the giants of Perl and Raku, absorb insights and innovations of the nerdy Perly community...everything they said in the blurb. It was very well organised thanks to Alex, Sawyer, Makoto, Amber and Peter, herding an army of volunteers. Such a knowledge-intensive event should be recorded for posterity, trapping the wisdoms and inspirations from the wise and inspiring in the container that is YouTube.

Well a nice banquate last night with good food and good company but a little sad that it was the last day.

To start off I atennded Sawyer X rather sad talk 'No one is Immune to Abuse' I cannot give this talk do justice in a short blog post so I suggest you seek out the recorded talk when it comes out. I will see if I can repost it here once it comes out. It had a large number of lessons for all of us in the Perl comunity.

Next up was me but unfortunetly I have some connection errors and had a little shorter talk and but both of the attendees gave me good feedback ;) oh well that is what happens when you are scheduled at the same time by two of the 'Big Wigs' in the Perl community. Luck of the draw I guess.