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These are some answers to the Week 227, 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 July 30, 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: Friday 13th

You are given a year number in the range 1753 to 9999.

Write a script to find out how many dates in the year are Friday 13th, assume that the current Gregorian calendar applies.

Example

Input: $year = 2023
Output: 2

Since there are only 2 Friday 13th in the given year 2023 i.e. 13th Jan and 13th Oct.

Previously I showed parts of the API of my new module Graphics::Toolkit::Color. This time I want to mention some bits about the code base, which demonstrate what I tried to say long ago (sorry for the long delay i hope I can complete the series).

Welcome

Please welcome the latest JSON tool for the command line: jp!

jp (mostly named from the Mojolicious class Mojo::JSON::Pointer that makes jp possible) is a command line tool for quickly extracting data from a JSON object.  How many times do we get a complex JSON object from some command and we just need to extract a specific set of values from it?  Every time!  All the time!  Often, people use basic tools like grep and sed.  Most people reach for jq, but I find the syntax too cumbersome to use just to extract my desired data.  I just want to use JSON Pointers and move on, but, indeed, sometimes JSON Pointers aren't even enough.  jp really shines with some helpful command line arguments, a regular expression JSON Pointer syntax, and, finally, a Perl eval argument for total power.

Get on with it

Let's see jp work.  Each example explainer links to the JSON Object used for the example.

Here's the most basic use.

$ jp /server/0/password < t/json1.json

REDACTED_APIKEYfalse

These are some answers to the Week 226, 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 July 23, 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: Zero Array

You are given an array of non-negative integers, @ints.

Write a script to return the minimum number of operations to make every element equal zero.

In each operation, you are required to pick a positive number less than or equal to the smallest element in the array, then subtract that from each positive element in the array.

Example 1:

To have a secure SMTP delivery, use Email::Sender. Mail::Sendmail uses SMTP for transport and there's no other type of transport. It does not support SMTP authentication, which my SMTP server now requires even for access from localhost. From what I read and tried once or twice in the past, the current "best practice" or recommended way is to use Email::Sender. Here's an incantation to send mail using sendmail:

use Email::Sender::Simple qw(sendmail);
use Email::Simple;
use Email::Sender::Transport::Sendmail qw();
use Try::Tiny;my $email = Email::Simple->create(
 header=>[To=>$to, From=>$from,
 Subject=>$subject],
 body=>$body,
);try {
 sendmail($email,
 {from=>$from,
 transport=>Email::Sender::Transport::Sendmail->new});
} catch {
 print "Can't send mail: $_";
}

• It's easy to switch transport to SMTP (just change two lines).

• It's easy to add SMTP authentication (just pass arguments to transport constructor).

• It's easy and clear where to add custom email headers (whereas in Mail::Sendmail, some arguments are "magical"/processed, they do not correspond 1:1 to headers).

• It's easy to construct multipart email (construct the appropriate $email object).

In addition:

• Envelope sender and RFC822 From is clearly separated, forcing beginners to understand the concept.

So there you have it, sending an temp email in Perl the modern way. No longer apt for one-liners though.

Kephra, an editor for programming (mostly Perl) written in WxPerl is my main project since I stumbled into the Perl community. Most people I know already heard of it - but I want to write about a new development that might be helpful for some, which might consider to use it even if it has a very limited feature set (forth rewrite baby!).

TPF has launched an online store with Perl merchandise (swag) celebrating the Perl 5.36 release. The marketing committee plan to do a custom celebratory collection for each release of Perl with revenue from each sale goes to TPF's Perl fund.

The store includes long- and short-sleeved t-shirts, sweatshirts, hoodies and stickers - all featuring a new Raptor image for the 5.36 release.

From: https://news.perlfoundation.org/post/tpf-merch-store

These are some answers to the Week 226, 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 July 23, 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: Shuffle String

You are given a string and an array of indices of same length as string.

Write a script to return the string after re-arranging the indices in the correct order.

Example 1

Input: $string = 'lacelengh', @indices = (3,2,0,5,4,8,6,7,1)
Output: 'challenge'

Example 2

Input: $string = 'rulepark', @indices = (4,7,3,1,0,5,2,6)
Output: 'perlraku'

Really, how hard could it be?

All this talk about types, objects, and systems, got me to thinking, "what would it take to create a 100% backwards-compatible pure Perl proof-of-concept for optionally typable subroutine signatures". I mean really, how hard could it be? So I started sketching out some ideas and here's what I came up with:

use typing;

sub greet :Function(string, number) :Return() {
  my ($name, $count) = &_;

  print "Hi $name, you have $count messages waiting ...\n";
}

Class::Plain provides a class syntax for the hash-based Perl OO.

Usage

As I sit pondering my peas at the dinner table, my thoughts are unnaturally drawn to the similarity between these pulses and Perl. A famous poet once said that "For a hungry man, green peas are more shiny than gleaming pearls". From these green orbs on my plate, the mind drifts to a recent virtual conversation regarding logos, branding, rebirth and innovation in Perl. One wonders whether such heated debates are important, relevant and what it might mean for Perl in the future. The Camel (from the O'Reilly Book on Perl) has long been the image associated with the language, along with the Onion (Origin perhaps from Larry Walls' "state of the onion" presentation). Personally it is not something that I feel passionately about. "Perl, with any other logo would be just as quirky" as Will Shakespeare is reported to have said. But The Camel is the popular, recognisable standard "logo" with some, as yet to be tested, copyright and trademark "issues"

These are some answers to the Week 225, 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 July 16, 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: Left Right Sum Diff

You are given an array of integers, @ints.

Write a script to return left right sum diff array as shown below:

Hello all. It's been a while. As you may have guessed there will not be a workshop this year. We spoke about organising one but the uncertainty around restrictions, along with other organisational constraints, resulted in our decision not to.

Inextricably bound

Perl isn't a strongly typed language, and its built-in types are limited and not generally accessible to the engineer, however, Perl supports various classes of data and in recent years has flirted with various ways of enabling runtime type checking.

In a strongly typed language the tl;dr; case for declaring data types is memory management, compile-time code optimization, and correctness. To this day I'm both impressed and horrified by the number of errors caught when I implement some kind of type checking in my programs. When it comes to runtime type checking we're only concerned with enforcing correctness.

Types, values, objects, signatures, and the systems that tie these all together, are all inextricably bound. They are necessarily interdependent in order to present/provide a cohesive and consistent system. Peeling back the layers a bit, types are merely classifications of data. Any given piece of data can be classified as belonging to a particular type whether implicit or explicit.

Eagle-eyed watchers of CPAN may have noticed that I've recently been releasing Type::Tiny development releases with version numbers 1.999_XYZ.

Type::Tiny v2 is intended to be compatible with Type::Tiny v1. If you've used Type::Tiny v1, you shouldn't need to change any code, but Type::Tiny v2 has a few new features which may make your code simpler, more maintainable, and more readable if you adopt them.

These are some answers to the Week 225, 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 July 16, 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: Max Words

You are given a list of sentences, @list.

A sentence is a list of words that are separated by a single space with no leading or trailing spaces.

Write a script to find out the maximum number of words that appear in a single sentence.

Example 1

Input: @list = ("Perl and Raku belong to the same family.",
                "I love Perl.",
                "The Perl and Raku Conference.")
Output: 8

Example 2

Just released Graphics::Toolkit::Color for the purpose to create computationally harmonic color pallets (2-3 lines max for most needs). It is in fact a chunk out of Chart I needed to reuse in other projects as the Harmonograph. And as you can see in the SEE ALSO section of the POD - I'm aware that there are plenty other modules doing, parts, similar stuff or even more.

Hello Fellow Perl mongers!

Every year in the month of October a company named DigitalOcean hosts an event named Hacktoberfest.

If you ever wanted to contribute to a Perl project now is a good time to give it a go!. Here are a few beginner friendly projects that are up-for-grabs and here is a list of Github projects with the "hacktoberfest' topic.

If you are a project owner and would like someone to participate in your project make sure to add the 'hacktoberfest" topic to a github/gitlab issue and promote your project on ( blogs.perl.org, perl.com/ ,Perlweekly, Perl Reddit , Medium ) or any other channels used to promote your Perl content.

Looking forward to seeing your Hacktoberfest pull requests!

How does SPVM resolve the problems of Perl numeric operations?

I hear Perl have the problems of numeric operation.

I realized this problems, and try to resolve them using SPVM. (SPVM is yet experimental release).

What is SPVM?

SPVM is a programing language to provide fast static-typed numeric operation and array operations into Perl.

I'm writing SPVM Language Specification now.

Do you want to use static typed numeric arrays(byte[], short[], int[], long[], float[], double[]) in Perl? You can write these using SPVM.