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These are some answers to the Week 269, 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 May 19, 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: Bitwise OR

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

Write a script to find out if it is possible to select two or more elements of the given array such that the bitwise OR of the selected elements has at least one trailing zero in its binary representation.

Example 1

Three Perl releases have been published this past week, containing patches for security issues CVE-2023-47038 and CVE-2023-47039. This kept us busy for the past few weeks (explaining the somewhat thinner recent updates).

• Paul will publish a post-mortem on the recent releases, looking at what went wrong and some thoughts on how to improve it so those don’t happen again
• We discussed a plan to improve documentation of the security disclosure process
• We took note of what projects we have in flight (e.g. PPCs being implemented) and may find a way to keep that list published and updated

Welcome back to another round of the weekly challenge, with just one solution this week. I'm setting up a lemonade stand and need to deal with change. Interestingly, I can only sell one juice per person, so I hope you're not super thirsty!

We can take $5, $10, and $20 bills, and we don't start with any change, so we need our previous customers to provide us with change for future customers. Let's find out if we can make change for a set of customers.

Here's the code:

A plenv plugin to add additional include directories to Perl.

This plugin sets the contents of file .perl-libdirs. It hooks into plenv-exec command and every time you run perl or any other command under plenv, plenv-libdirs uses the .perl-libdirs files to set the PERL5LIB environment variable.

plenv-libdirs makes use of .perl-libdirs files in the current working directory and every directory between it and root. Environment variable PERL5LIB has a list of paths separated (like in PATH) by a colon on Unixish platforms and by a semicolon on Windows (the proper path separator being given by the command perl -V:path_sep). When plenv-libdirs collects the paths from .perl-libdirs files, the order of the paths follows the order of the directories. The longer the path to .perl-libdirs file, the higher precedence in PERL5LIB.

These are some answers to the Week 268, 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 May 12, 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: Number Game

You are given an array of integers, @ints, with even number of elements.

Write a script to create a new array made up of elements of the given array. Pick the two smallest integers and add it to new array in decreasing order i.e. high to low. Keep doing until the given array is empty.

Example 1

Emacs comes with two different major modes to edit Perl code: perl-mode and cperl-mode.

perl-mode is somewhat stuck with the Perl syntax of 5.14, has less features, but a cleaner implementation. cperl-mode is up to date with Perl 5.38 and has deeper understanding of Perl syntax, but a somewhat arcane implementation, most of it written in the previous century.

With all due respect to TIMTOWTDI, maintaining two major modes turns out to be not enough fun in the long run, and last week Stefan Kangas opened a wishlist item to Making perl-mode.el obsolete.

The mail thread shows that some people prefer perl-mode because it is less "colorful" and intrusive than cperl-mode. Therefore, the idea is to enable cperl-mode to (optionally) look like and behave like perl-mode. That way, perl-mode.el can be obsoleted without making those users uncomfortable: perl-mode would continue to exist as a custom theme of cperl-mode.

Hi everybody, we've got another two challenges this week, so let's dive into them!

Remove One

The goal is to see if there's any one number that can be removed to make the set sorted in increasing order. Here's the code:

These are some answers to the Week 268, 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 May 12, 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: Magic Number

You are given two arrays of integers of same size, @x and @y.

Write a script to find the magic number that when added to each elements of one the array gives the second array. Elements order is not important.

Example 1

Two of us again, here's the summary of our meeting:

• While implementing PPC 0013, it turned out it was vague in some places, so further discussions and refinements to the PPC document are needed
• POD extensions - do we keep stealing features from Markdown (like tables, images, language markers)? Do we switch to Markdown? Neither are easy.
• We’ve disabled the Wiki and enabled Issues on the PPCs repository, to better separate discussions on the form and substance of PPCs
• PPC 0022 will soon be merged, and moved to “Exploratory” status

Whohoo release 1.7 (and 1.6) brought a thorough architectural rewrite, new color spaces (HSV, HWB, YIQ), new formats ([named] array, string and css_string), choosable value ranges, closed both open issues, and introduced the named argument API I wrote last time about. And as promised, this post is about the methods: distance, set, add and blend.

In the final part of this series, we will test the performance of the four parsers, in a scenario emulating the batch analysis of sequencing data. We will use the sample fastq file 3_OHara_S2_rbcLa_2019_minq7.fastq from https://zenodo.org/record/3736457. This is a 35MB file of 21791 long sequences for a nanopore experiment. Download the data and save them to a directory in your hard disk. Then use the following bash time_fastq2a_shell.txt (change the extension to .sh before running!) to process this file 500 times with each of the four methods : seqtk (C), seqkit (Go), perl - regex (code presented here  saved into fastq2a_regex_comp_in_func.pl file) and perl - flag (code presented there saved into the fastq2a_flag.pl file).

These are some answers to the Week 267, 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 May 5, 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: Line Count

You are given a string, $str, and a 26-items array @widths containing the width of each character from a to z.

Write a script to find out the number of lines and the width of the last line needed to display the given string, assuming you can only fit 100 width units on a line.

Example 1

There were only two of us this week, and the list is still a bit quiet.

The main topic was stalled PPC work: we have a few PPCs that have been approved and are in the “Implementing” state, but still waiting for an implementor. We’ll send a separate email asking for volunteers on those.

CGI::Tiny is a very nice, Perlish way to construct CGI scripts these days. It is perfectly suited as a replacement to CGI.pm and is quite at home in a shared hosting environment.

Here's the example from the POD [1] on metacpan:

    use CGI::Tiny;
    cgi {
      my $cgi = $_;
      # set up error handling on $cgi
      # inspect request data via $cgi
      # set response headers if needed via $cgi
      # render response with $cgi->render or $cgi->render_chunk
    }; 
        

I recently coupled this with my new module Dispatch::Fu [2], and it worked exceedingly well. It is a darn pleasure to consider from a distance, if I do say so myself:

Hi everybody! Back this week with a (surprisingly long) solution to just Task 1 of the weekly challenge. Task 2 makes no sense to me at all because it seems like examples 1 and 3 disagree with each other. Just sticking to one challenge for that reason. Anyways, let's dive into it!

The goal here is to find the letters that all the provided words share. Here's the code:

These are some answers to the Week 267, 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 May 5, 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: Product Sign

You are given an array of @ints.

Write a script to find the sign of product of all integers in the given array. The sign is 1 if the product is positive, -1 if the product is negative and 0 if product is zero.

Example 1

Input: @ints = (-1, -2, -3, -4, 3, 2, 1)
Output: 1

The product -1 x -2 x -3 x -4 x 3 x 2 x 1 => 144 > 0

Example 2

This week we:

• Reviewed some recent email threads:
  • Returning values from require multiple times - seems not useful as compared to using do FILE or the new load_module builtin
  • CPAN.pm observed to use lots of memory, but also complicated to fix. It might benefit a new smaller simpler tool being provided by Perl core
• Perl 5.39.5 is due soon and we have release managers up to 5.39.8, but we’re still in need of folks to do up to 5.40.0

One of my 'nuts and bolts' modules is constant::more. It declares constants, just like constant , however also gives you the ability to set these values in a consistent way from the command line or environment variables.

This can give module authors constants with 'default values', and allow the top level application code to override from the command line if they choose.

This has worked well for my needs to date. I've just released v0.3.0 with some additional features I feel make it even more useful and might make it more useful for others:

Flat list of for multiple constants

Originally I made the interface only work like constant for simple use cases. This meant multiple constants had to be inside a hash ref of actually multiple use constant::more... lines.

use constant::more {CONST1=>1, CONST2=>2};

Now a flat list is usable, which I personally find much more appealing:

use constant::more CONST1=>1, CONST2=>2;

Enumerations

We’re excited to announce that Ruth Holloway (GeekRuthie) has joined the Dancer Core Team.

Ruth is a longtime user of Dancer2, and has been one of our most vocal supporters in the greater Perl community. She’s responsible for a number of excellent additions to the Dancer2 ecosystem, and is an active member of our wonderful community.

Please join us in welcoming Ruth to our team. We’re looking forward to her continued contributions to the framework and community.

In other news, Steven Humphrey has retired from the Core Team. We’re grateful for his contributions to Dancer2, and wish him well in his future endeavors.