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We

• Arranged for a representative from TPRF to join us in January to discuss roadmaps
• Started discussing what might turn up in the PSC talk at FOSDEM

We’re skipping next week due to Christmas, so next meeting should be on 2024-01-04

These are some answers to the Week 269, 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 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 2: Distribute Elements

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

Write a script to distribute the elements as described below:

1) Put the 1st element of the given array to a new array @arr1. 2) Put the 2nd element of the given array to a new array @arr2.

Once you have one element in each arrays, @arr1 and @arr2, then follow the rule below:

If the last element of the array @arr1 is greater than the last element of the array @arr2 then add the first element of the given array to @arr1 otherwise to the array @arr2.

When done distribution, return the concatenated arrays. @arr1 and @arr2.

Yes, it's true. Config::Tiny now allows you to assign an array of values to a key.
The docs have been updated to include a new section, ARRAY SYNTAX.
Various examples are documented there and in test files. Sample usage:

[section]
greetings[]=Hello
greetings[]=World!
one=two
Foo=Bar

Note: The 2 lines of greetings can be separated by other lines too.

You access these values like this:
say $Config->{section}->{greetings}->[0];
say $Config->{section}->{greetings}->[1]

This patch was kindly provided by Steven Schoch.

See the Changes file for details.

On behalf of the Dancer Core Team, I am beyond excited to present you with Dancer2 1.0.0.

So how did we get here? Why now? I'll cover the specifics in a future blog post, but suffice it to say for now, we're stable, and we've been stable for a long time, but this was never reflected in our versioning. It's beyond time to commemorate that milestone.

If you're expecting big changes, you'll be disappointed that there aren't many on the technical side. Much of what's in this release involves adding some polish in spots, and smoothing out some jagged edges in others. Some important highlights include:

This week, Graham was on holidays, so Paul and Philippe:

• reviewed new mailing list threads. Just one - a rethink of signatures.
• submitted a talk proposal to the Perl dev room at FOSDEM
• continued to discuss the complexities of moving past the number ‘5’ for the major part of the language version

Quote of the week: “There are features that make the language slow, but those are the features that make the language.”

These are some answers to the Week 238, 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 October 15, 2023 at 23:59). This blog post offers some solutions to this challenge. Please don’t read on if you intend to complete the challenge on your own.

Task 1: Running Sum

You are given an array of integers.

Write a script to return the running sum of the given array. The running sum can be calculated as sum[i] = num[0] + num[1] + …. + num[i].

Example 1

Input: @int = (1, 2, 3, 4, 5)
Output: (1, 3, 6, 10, 15)

Example 2

Input: @int = (1, 1, 1, 1, 1)
Output: (1, 2, 3, 4, 5)

Example 3

Hello everybody! Welcome back to the Weekly Challenge series, where today we're working on dates again. I like these challenges in particular, for some reason. In this case, we have a rather simple challenge except that it gives us less common date formats than usual.

The challenge gives us a year, month, week(day) of the month, and day of week. Now DateTime provides us with get operations to find WoM and DoW info, but it doesn't provide set operations. For that we need to do a little math. Here's the code below:

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.

This week we:

• Worked out final resolving actions for security issues.
• Discussed recent mailing-list posts about making method non-public by default. This probably won’t work but we could open a PPC discussion on my method + $obj->&method syntax.
• Reviewed Projects in Flight - posted below
• Merged the PR for PPC 0022 (Metaprogramming API). Discussions on individual points can be made using GH Issues

Projects in Flight

• HTTPS out of the box — (Paul) has nudged Mark Gardner by email
• PPC 0013 overload in join — (Philippe) should open an issue with his thoughts on the topic
• PPC 0014 English names — (Paul) should check in with Joe McMahon
• PPC 0019 qt Strings — (Paul) now has TPF Core Development Grant so can start writing this Any Day Now(TM)
• PPC 0021 Optional chaining — (Paul) should check in with Veesh Goldman
• PPC 0022 Metaprogramming API — (Paul) has a CPAN module, would be nice if anyone started using it for any reason
• (Graham) to write a PPC for ->&
• Perl roadmap for 2024 — Yeah it’d be nice if we had one, but without having any weight of promise behind it it’s just words
• TODDR to write a draft pod/security_disclosure_process.pod (not in December), and also offered to coordinate the next incident

These are some answers to the Week 236, 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 October 1, 2023 at 23:59). This blog post offers some solutions to this challenge. Please don’t read on if you intend to complete the challenge on your own.

Task 1: Exact Change

You are asked to sell juice each costs $5. You are given an array of bills. You can only sell ONE juice to each customer but make sure you return exact change back. You only have $5, $10 and $20 notes. You do not have any change in hand at first.

Write a script to find out if it is possible to sell to each customer with correct change.

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.

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

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:

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.

These are some answers to the Week 235, 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 September 24, 2023 at 23:59). This blog post offers some solutions to this challenge. Please don’t read on if you intend to complete the challenge on your own.

Task 2: Duplicate Zeros

You are given an array of integers.

Write a script to duplicate each occurrence of ZERO in the given array and shift the remaining to the right but make sure the size of array remain the same.

Example 1

Input: @ints = (1, 0, 2, 3, 0, 4, 5, 0)
Ouput: (1, 0, 0, 2, 3, 0, 0, 4)

Example 2

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

Example 3

The PSC met today. In summary:

• Paul’s TPRF grant was accepted, he plans to spend some of that time to work on some PPCs first (qt strings, overload)
• FOSDEM Perl Devroom CfP: none of us are planning to attend in person, but if someone else wanted to present on our behalf we could coördinate with them and work out a subject to talk about
• Discussed coming up with a Perl roadmap that we could present to the world (and entice sponsorship for TPRF’s Perl Development Fund and Grants program)
• We discussed opening up our meetings to the occasional guest, so they could see what we’re actually doing (boring!) and give us an outside perspective

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).

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:

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