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The Persuaders! is a particularly silly 1970s action TV series which lasted for only one season. Tony Curtis plays Danny Wilde to Roger Moore's Lord Brett Sinclair. Tony is the funny guy and Roger is the straight man. After the Persuaders, Roger Moore went on to become James Bond, and Tony Curtis went on to date Debee Ashby.

Although it wasn't a hit in America, The Persuaders actually became more popular in translation than in the original. One of the running gags is American Danny (Tony Curtis) making fun of snooty, toffee-nosed, upper-crust "your lordship" Roger Moore. But since the translated versions were for people who didn't know anything about British or American people, the translators invented new dialogue unrelated to the original, which ended up being more entertaining for the audience than the English dialogue. Which has nothing to do with Perl but here we go.

These are some answers to the Week 145 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 2, 2022 at 24:00). 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: Dot Product

This first task of this week’s challenge was covered in this blog post.

Task 2: Palindromic Tree

You are given a string $s.

Write a script to create a Palindromic Tree for the given string.

I found this blog explaining Palindromic Tree in detail.

Example 1:

Input: $s = 'redivider'
Output: r redivider e edivide d divid i ivi v

Example 2:

Input: $s = 'deific'
Output: d e i ifi f c

Example 3:

Need some joy this holiday season? Head over to the Dancer Advent Calendar for this year's Twelve Days of Dancer. With a little help from our friends, we've put together a 12-day mini advent calendar featuring some great software built in Dancer, some helpful tips and tricks, new features, and more.

Thanks for being such a great community, and for your continued support of Dancer! Wishing you the happiest of holiday seasons!

CromeDome (on behalf of the Dancer Core Developers)

Throwing this one out to the wider community, if anyone can assist in adding https support to strawberryperl.com that'd be great, with browsers and corporate firewalls moving towards a stricter mode of operation. An existing issue is here, with some history for those interested. Thanks in advance.

I spent quite a lot of time trying to work out what this error message meant:

Error: Unterminated '#if/#ifdef/#ifndef' in Libpng.xs, line 1328

The first problem here is that line 1328 is the end of the file, so that wasn't a big help.

After spending a lot of time counting #if and #endif statements in the file over and over again, in the end I had the bright idea of looking at the actual XS output, and managed to find the problem. Apologies for quoting it in full here but I can't think of a good way to truncate it:

These are some answers to the Week 145 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 2, 2022 at 24:00). 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: Dot Product

You are given 2 arrays of same size, @a and @b.

Write a script to implement Dot Product.

Example:

@a = (1, 2, 3);
@b = (4, 5, 6);

$dot_product = (1 * 4) + (2 * 5) + (3 * 6) => 4 + 10 + 18 => 32

An important point is that we are told that the arrays have the same size. Thus, we don’t need to check that. We’ll also assume that they contain only numbers.

Dot Product in Raku

The Perl core team seems to be looking for resources to help in language development.

Currently, it seems the material in python.

perlgov: the perl governance document

I feel that Perl and Python cultures are quite different.

It's also based on an improvised document in 2019 when the Python reader quit.

I can understand how envious we are when we see Python attracting users(although
I'm watching a lot of cheating at the same time).

On the other hand Perl has long been a conservative culture.

So, we can refer to the methods used by developers of languages, operating systems and tools that also have a conservative mindset.

The first thing I would like us to refer to is the method used by the group that creates C language specifications.

C language specification creating group

C89, C99, C11

Development of C language has continued some slowly, but functions that users think are lacking have been added.

Specially C99 is added good features I wanted.

It would be worthwhile to ask the C specification group how it was achieved.

I think it's less repulsive and less likely to fail if we adopt a method from a culture similar to Perl rather than a culture opposite to Perl.

Welcome last month of the year 2020

Generally, I always look forward to festive month, December. But I don't expect it to be any different from other months, unfortunately.

With so much going on in my personal life, it is hard to focus on anything. One thing that I really miss these days are personal time. I am constantly working on it with the help of experts in the field. I try to look at the positive side of the life but I can't ignore the fact I am not giving 100% to my pet project The Weekly Challenge. Having said that I must thank the entire team for the support and encouragement in this difficult time. As of today, we entered into the 89th week. I can't wait to see when we get to the 100th week.

These are some answers to the Week 144 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 December 26, 2021 at 24:00). 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: Semiprimes

Write a script to generate all Semiprime number <= 100.

For more information about Semiprime, please checkout the Wikipedia page.

In mathematics, a semiprime is a natural number that is the product of exactly two prime numbers. The two primes in the product may equal each other, so the semiprimes include the squares of prime numbers.

Example:

10 is Semiprime as 10 = 2 x 5
15 is Semiprime as 15 = 3 x 5

If you want to challenge yourself on programming, especially on Perl and/or Raku, go to https://perlweeklychallenge.org, code the latest challenges, submit codes on-time (by GitHub or email).

This blogpost is not in shortage of unanswered questions...

Task 1 Array of Product

Despite the holiday week here in the U.S., I was able to tackle this week's Perl Weekly Challenge. I have to say that this week's challenge was the most satisfying for me as it allowed me to not only come up with a novel solution (for me!), but it also provided an opportunity for me to leverage two areas of Perl programming that have been a real challenge for me: recursion and references. The deadline to submit solutions for this challenge is fast approaching so if you haven't solved it yourself yet, you may want to come back to this post later.

Task 1

Task #1, "Array of Product", asks the following:

You are given an array of positive integers @N.

Write a script to return an array @M where $M[i] is the product of all elements of @N except the index $N[i].

Example 1:

The other day I wanted to send my friend some silly emojis on LINE and so I updated my flaky old Unicode browser to the new-fangled Unicode with values above 0x10000, so that I could fetch the Emojis, which start around here. The thing also features a perl script which fetches values from Unicode::UCD using the charinfo function. I also updated to Perl 5.32 around the same time. Now the funny thing was that I started getting all kinds of errors about invalid JSON in the browser console. My Perl script was sending something of the form {... "script":Common ...} from my module JSON::Create, which is not valid JSON due to not having quotes around Common, and obviously my module was faulty.

These are some answers to the Week 143 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 December 19, 2021 at 24:00). 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: Calculator

You are given a string, $s, containing mathematical expression.

Write a script to print the result of the mathematical expression. To keep it simple, please only accept + - * ().

Example 1:

Input: $s = "10 + 20 - 5"
Output: 25

Example 2:

Input: $s = "(10 + 20 - 5) * 2"
Output: 50

Calculator in Raku

If you want to challenge yourself on programming, especially on Perl and/or Raku, go to https://perlweeklychallenge.org, code the latest challenges, submit codes on-time (by GitHub or email).

Task 1 Longest Consecutive Sequence

Does anybody know Rob Seegel (aka RCS), the author/maintainer of Tk::MListbox?

I tried to contact the author by e-mail but didn't get any feedback so far.
I would like to adopt the module Tk::MListbox (and the other packages).

For a long time (since 2012), REST::Neo4p has provided a way for Perlers to play, and even work, with the graph database Neo4j.

Neo4j has made many changes and improvements in its server and its query language in that time. However, as it has become successful commercially, it has made breaking API changes of one kind or another more and more regularly. In the last major release, version 4.0, Neo4j retired the REST endpoint on which REST::Neo4p was based. This endpoint was "entity-based", as it were, allowing direct access to nodes, relationships, and the like via entity IDs. It was well suited to the object (HAR HAR) of REST::Neo4p. But Neo4j decided to focus exclusively on its declarative query language Cypher, and to move away from the "graph walking" paradigm that the REST endpoint represented.

These are some answers to the Week 142 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 December 12, 2021 at 24:00). 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: Divisor Last Digit

You are given positive integers, $m and $n.

Write a script to find total count of divisors of $m having last digit $n.

Example 1:

Input: $m = 24, $n = 2
Output: 2

The divisors of 24 are 1, 2, 3, 4, 6, 8 and 12.
There are only 2 divisors having last digit 2 are 2 and 12.

Example 2:

Most operating systems have a version of libpng, the library for reading and writing the PNG (portable network graphics) image format on them. Unfortunately, though, the libpng is often fairly old.

I wrote a CPAN module which links against libpng, but then trying to get the module tested with CPAN testers, a lot of bugs would happen. It was frustrating because I couldn't work out what was going wrong with the tests unless I could find out what version of libpng was installed on the testing machine.

The solution I came up with in the end was a bogus test file which merely prints the libpng version as its skip_all message. This turned out to be quite effective in working out what is going wrong as various improvements to my PNG module turn out to trip bugs in older versions of libpng.

(Originally published on samirparikh.com.)