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These are some answers to the Week 255, 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 February 11, 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: Odd Character

You are given two strings, $s and $t. The string $t is generated using the shuffled characters of the string $s with an additional character.

Write a script to find the additional character in the string $t.

Example 1

Input: $s = "Perl" $t = "Preel"
Output: "e"

Example 2

Input: $s = "Weekly" $t = "Weeakly"
Output: "a"

Example 3

Just me and Graham this week.

• builtin::nan needs better documentation on the kind of NaN it provides.
• We discussed lots about builtin and lexical imports, and how to handle a few odd cornercases.
• Perl 5.39.7 is now out; we need to work out the schedule for the final few devel releases and the real thing in May.

Hello everybody! For this week's weekly challenge I thought the challenges looked really easy, but they both had a couple slight complicating factors. Also, this was the first time I've used sub signatures.

Similar Words

For this one, we're looking for words that share all characters. We print out each pair of countries.

These are some answers to the Week 254, 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 February 4, 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: Reverse Vowels

You are given a string, $s.

Write a script to reverse all the vowels (a, e, i, o, u) in the given string.

Example 1

Input: $s = "Raku"
Output: "Ruka"

Example 2

Input: $s = "Perl"
Output: "Perl"

Example 3

Input: $s = "Julia"
Output: "Jaliu"

Example 4

After written about the origin and goals of Graphics::Toolkit::Color -- let's take a look at the public methods and make it a little study of good API design. But lets work our way up from a few examples:

I don't really keep up with online resources, and I blogs.perl.org to be (like perl) a nice and stable home. I've watched resources come and go - I've lost untold content in the process (geocities, myspace, LtU, hello??).

I recently discovered dev.to because of a nice benchmarking article published by a long standing community member:

Benchmarking Perl Core Class in v5.38 By John Napiorkowski

https://dev.to/jjn1056/benchmarking-core-class-573c

So I guess this is like some kind of substack for developer blogging? I only recently discovered that resource also.

Crossposted from my blog

My upgrade of my home server from Debian 11 ("bullseye") to Debian 12 ("bookworm") went almost without a hitch. Yesterday I realized that the Postgres data hadn't been migrated from the old DB to the Debian package of Postgres 15. But luckily, the good Pg people provide a Debian package of 9.6 (the version which held my data) for Debian 12. I could install that one, fire it up, dump all data into SQL, fire up Pg 15 from Debian and import it there. Now I run such an SQL dump daily, just to have the data available as SQL files.

I wonder if it would be worthwhile for Perl to provide prebuilt binaries/packages of old Perl versions for current OSes, but then, there are so many build options that it's not worth the effort in general.

These are some answers to the Week 254, 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 February 4, 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: Three Power

You are given a positive integer, $n.

Write a script to return true if the given integer is a power of three otherwise return false.

Example 1

Input: $n = 27
Output: true

27 = 3 ^ 3

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

I noticed the other day we had an old utility script txt2html.pl that gave a warning
/usr/local/bin/txt2html.pl
$* is no longer supported at /usr/local/bin/txt2html.pl line 1512.
Apparently $*=1 was how multi-line regex searching was done in old perls.

$a =~ m /foo/ms;

$ sudo cpanm HTML::TextToHTML

In my google search on the warning, I found this call for help:
https://github.com/resurrecting-open-source-projects/txt2html/blob/master/CONTRIBUTING.md
so added a github Issue and emailed the author saying the updated and migrated txt2html.pl was already available on CPAN.

Introduction

I have been leaning very heavily on Perl's prototype feature for creating new modules. The imptetus for this can traced back to the day I looked at the source code for Try::Tiny, and realized that it was implemented using prototypes. The main reason for using prototypes for many new modules I've created recently is my focus on making a thing I do repeatedly available in a more Perlish or idiomatic way.

Required reading if you have not and are about to dive into an article about prototypes: Far More Than Everything You've Ever Wanted to Know about Prototypes in Perl by Tom Christiansen.

The following article demonstrates 2 CPAN modules I have written that focus more on Perl programmer UX and why Perl prototypes can provide a way forward for a great many ideas that people have. Prototypes misunderstood, yes; but more so, they are misunderestimated. They are infact, very powerful and when used for their intended purpose; a lot of hand wringing can be avoided during feature discussions.

These are some answers to the Week 253, 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 January 28, 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: Weakest Row

You are given an m x n binary matrix i.e. only 0 and 1 where 1 always appear before 0.

A row i is weaker than a row j if one of the following is true:

a) The number of 1s in row i is less than the number of 1s in row j.

b) Both rows have the same number of 1 and i < j.

Write a script to return the order of rows from weakest to strongest.

Example 1

The three of us met today, and we:

• updated the status of stalled PPCs (after discussion with the proposers)
• assigned a number (0023) to the map my $x { } PPC
• discussed the evaluation order issue related to PPC 0021 (optional chaining)
• decided that future rejected PPCs should have a section that details why they were rejected
• discussed the tooling around the publication of dual-life modules on CPAN

Hi all,

Please note that Komodo IDE is now open source. Komodo IDE is a very feature-rich Integrated Development Environment (IDE). Basically a sophisticated source-code editor. Notable features why I used Komodo IDE:

• Syntax highlighting
• Code intelligence (autocomplete, code refactoring etc.)
• Run and debug programs easily
• Debug with breakepoints and inspect the variables and their values in the GUI
• Integrates with version control

You can read more about Komodo IDE here.

The blog post announcing Komodo IDE going Open Source is here.

The blog post also contains an explanation why it is made open source. One of the reasons is that there is already a lot of free and good editors available, e.g. Visual Studio Code. Though, as I was using Komodo IDE for at least 7 years now, I still very much like it and it’s OOTB feature set.

Hi everybody! In this week's weekly challenge, we're searching for anything but the minimum or maximum in a dataset, and searching for senior citizens on a plane.

Min And Max

This challenge is a very interesting one, because obviously the easiest solution in terms of development is to sort and filter the first and last element. However, that is O(n log n) and it's very little added complexity to do the O(n) solution with a single-pass filter.

These are some answers to the Week 253, 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 January 28, 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: Split Strings

You are given an array of strings and a character separator.

Write a script to return all words separated by the given character excluding empty string.

Example 1

Input: @words = ("one.two.three","four.five","six")
       $separator = "."
Output: "one","two","three","four","five","six"

Example 2

Input: @words = ("$perl$$", "$$raku$")
       $separator = "$"
Output: "perl","raku"

Split Strings in Raku

We discussed

• lwn.net writes a lot about Python. Should we let them know “Hey Perl still exists, here’s what we’re doing” too?
• Reviewed a draft of some slides for the “Updates from the PSC” FOSDEM talk
• Discussed some thoughts around getting use VERSION to imply builtins
• Further clarifications were made on the PPC0019 (qt strings)

DBD::SQLite 1.73_01 (with SQLite 3.42.0) is a release candidate for the next stable DBD::SQLite. This release is mainly to upgrade the bundled SQLite library.

I'll wait for about a month and release 1.74 in the middel of September if there's no blocker nor request to wait for more. Thank you for your patience.

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: