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These are some answers to the Week 35 of the Perl Weekly Challenge organized by Mohammad S. Anwar.

Spoiler Alert: This weekly challenge deadline is due in a few days (November 24, 2019). This blog post offers some solutions to this challenge, please don't read on if you intend to complete the challenge on your own.

This week, both tasks were contributed by Paul Johnson.

I usually first do task 1 in Perl 5 and in Raku (formerly known as Perl 6), or sometimes the other way around, and then task 2 in both languages. This week, however, the two tasks are so closely related that it makes sense to do both tasks together in one language, and then the two tasks in the other language.

The tasks

Task # 1: Encode Text into Binary Encoded Morse Code

Write a program to encode text into binary encoded morse code.

Pay attention to any changes which might need to be made to the text to make it valid morse code.

Well after the panic stations I talked about in my last post. I have calmed down a little. It seems that huge check in was for the compiled version of the code base and 99% of the changes where just auto-auto-generated stuff chugged out by boto when it re-compiles.

That being said I did find this thread while investigating the mother of all pushes; https://github.com/pplu/aws-sdk-perl/issues/244

Requirements for stabilisation?

shadowcat-mst commented on 24 May 2018
So, a number of components in Paws have something like this -
https://metacpan.org/source/JLMARTIN/Paws-0.36/lib/Paws/S3.pm#L2
Is there a list anywhere of what's required to get to the point where that warning can go away? If not, how would we go about getting to a point where there was such a list?

When I started working at SUSE, one of the first things I worked on is the maintenance of the perl modules repository in the openSUSE Build Service (OBS).

We are using a tool called cpanspec to create .spec files from CPAN modules. From the spec file, the OBS then builds rpm packages.

I noticed there are a lot of modules missing information, or having other problems that prevent us from automatically create a working .spec file.

October has been always the busiest month of the year for one annual event Hacktoberfest. However this time, we have had London Perl Workshop annual event as well. On top of all these, I have had to manage Perl Weekly Challenge. I have been participating Hacktoberfest since 2015. It was first introduced to me by Neil Bowers. Last year, I contributed 155 Pull Requests in the month of October. Having done this, I never thought I would ever break this record. Luckily I submitted 160 Pull Request last month.

Here is the breakdown:

• Merged: 90
• Close (unmerged): 17
• Open: 53

These are some answers to the Week 34 of the Perl Weekly Challenge organized by Mohammad S. Anwar.

Spoiler Alert: This weekly challenge deadline is due in a few days (November 17, 2019). This blog post offers some solutions to this challenge, please don’t read on if you intend to complete the challenge on your own.

This week, both tasks were contributed by Dave Cross.

Task # 1: Array and Hash Slices

Write a program that demonstrates using hash slices and/or array slices.

Slices are a way to access several values of an array or of a hash in one statement, by using multiple subscripts or keys.

Array and Hash Slices in Perl 5

If you have an @array containing for example some successive integers, you can obtain several values from it with the following syntax: @array[3, 7, 2] or even @array[2..7].

We are lost.

Temptation and desires will make us lost.

Where is Perl going after Raku begins to take a different path?

Raku provides new values.

Perl provides traditional and conservative values.

If you lead Perl to Raku, Perl will fail.

If you ask Raku for Perl, Raku will fail.

When we talk, we need to be aware of the difference between Raku and Perl.

We are lost.

Those who like traditional Perl have respected SUPER and bless.

Those who aim for Raku have thought that SUPER and bless are failures.

That has become a negative campaign against Perl.

We may need to go back to the fundamentals of what Perl offers.

The Perl language is a good language, but the Perl community continues to fail in marketing.

What benefits does Perl offer?

What is Perl's mission?

Who is a Perl user?

Where is Perl used?

What are the strengths of Perl?

What is Perl's vision?

We talk a lot about the details of the language, but haven't talked about the value that Perl offers to society.

Isn't it time for the Perl core team to start talking about Perl marketing?

I've spent more than four years working on Raspberry Pi stuff for Perl, and although it's only garnered a relatively small but thorough interest, it's been a wonderful one to be a part of.

Mozilla has opened up a new IoT Platform, and I'm wondering if it'd be worth the time to provide a Perl interface to it or not.

Thoughts?

Paws S3 is coming together nicely I just have one more 'S3' todo test to look at and that is the get 'ListObjectVersions' test.

To start I fixed up the 'ListObjectVersions' test much like this

These are some answers to the Week 33 of the Perl Weekly Challenge organized by Mohammad S. Anwar.

Spoiler Alert: This weekly challenge deadline is due in a few days from now (November 10,, 2019). This blog post offers some solutions to this challenge, please don't read on if you intend to complete the challenge on your own.

Challenge # 1: Count Letters (A..Z)

Create a script that accepts one or more files specified on the command-line and count the number of times letters appeared in the files.

So with the following input file sample.txt:

The quick brown fox jumps over the lazy dog.

the script would display something like:

This is a sensible step forward for both languages.

The moderators of r/perl have had a discussion and we've agreed that going forward, this subreddit will be for the discussion of Perl 5 (and, I guess, earlier versions). Posts about Raku are off-topic here. I think that's what most readers here wanted and I think the Raku people will welcome the separation too.

See all the discussion at https://www.reddit.com/r/perl/comments/dmtxk1/raku_posts_in_rperl/

At first, see the following entry.

Data Science and Perl

Our company goes into many other companies and helps them build new Perl systems or fix old ones. Needless to say, we see how many companies work and a typical example is one of our clients I'll call "AlphaCorp." They use lots and lots of Perl. Their primary web site is almost entirely Perl. So when I went in to help them with their A/B testing (amongst other things), I was surprised that they also used a lot of Python. It turns out they had a specific need that Python fills and Perl does not: data science.

After thinking a few weeks, I create the plan to do Data Marketing.

Data Marketing Plan by Perl modules

This is Japanese. Please translate it using google translation.

The next action I had a crack at was 'PutCORSConfiguration' and I was getting the usual;

<Error>
  <Code>MalformedXML</Code>
  <Message>The XML you provided was
 not well-formed or did not validate against
 our published schema
  </Message>
</Error>

At this points in my Paws adventure I checked the API doc for URI Request Parameters of the PutCORSConfiguration;

PUT /?cors HTTP/1.1 Host: Bucket.s3.amazonaws.com Content-MD5: ContentMD5

and I see I don't have to deal with the 'id' in the 'URI' bug here as I get what I want in the request URI;

The official Perl documentation site at https://perldoc.perl.org was recently overhauled. Independently, I put together a reimagined documentation site that would be hosted at https://perldoc.pl. In the interest of providing a documentation site that best serves the needs of the Perl community, we need your feedback. Please give both sites a try, in-depth if you want, or just how you would most commonly use the site. What do you like about the design or the functionality of each site? What is missing or can be improved? Any feedback regarding what you want from the Perl documentation site is helpful and appreciated. Please leave comments here or in the linked posts by Monday Nov 18th.

Reddit comments

PerlMonks comments

Division by zero

Create a function to check divide by zero error without checking if the denominator is zero.

Perl already checks the denominator when dividing. All we need to do is to catch the exception it throws and check it instead of checking the value of the denominator.

The following division subroutine uses Try::Tiny to catch the exception. It’s a good practice not to use the low level eval, see for example Bug in eval in pre-5.14 for the reasons.

DISCLAIMER: All photos courtesy to the official twitter handle of London Perl Workshop.

As you know, LPW2019 just happened last Saturday 19th Oct 2019. It was my second year as a member of LPW Organizing team. Although I was the least active members in the team as compared to others. On the day, I arrived the venue around 8:10 am and saw Katherine, Tom and Lee unloading event materials from the cab. I joined the team and gave helping hands. I was managing the registration desk along with Katherine. People sarted arriving about 8:30 am. It was always great to see so many friends.

We last left out PAWS hero she was just about ready to fix the S3 'PutBucketAnalyticsConfiguration' call. Having first fixed up the botocore json file to properly define the URI for the call.

She now had to find a way to get the 'xmlns' schema attribute add to the root of the XML that is sent to the API.

Turns out I was in very virgin territory there has been no Paws code to take this into account and checking the py code it was not very helpful so I have to put my thinking cap on for this one.

I was thinking I could just make it a new 'trait' like I did for the 'Status' attribute but then I remembered some of my XML from years ago the the 'xmlns' always should be in the root node so It will appear only in one place so not really an attribute trait.

MooX::Press is a quick way of building a bunch of Moo roles and classes in one use statement.

The most basic example would be:

  package MyApp {
    use MooX::Press class => ['Foo', 'Bar'];
  }
  
  my $thing1 = MyApp::Foo->new();
  my $thing2 = MyApp->new_foo();   # alternative constructor

But do-nothing classes with a constructor and nothing else aren't very exciting. Let's define a class with some subclasses which have attributes and roles and methods and stuff.

These are some answers to the Week 31 of the Perl Weekly Challenge organized by Mohammad S. Anwar.

Spoiler Alert: This weekly challenge deadline is due in a few days from now (October 27, 2019). This blog post offers some solutions to this challenge, please don't read on if you intend to complete the challenge on your own.

Challenge # 1: Illegal Division by Zero

Create a function to check divide by zero error without checking if the denominator is zero.

Illegal Division by Zero in Perl 5

Perl 5 has a number of modules to implement exception handling using the try ... catch pattern found in a number of other languages, such as, for example, Try::Tiny or TryCatch. Even Autodie might actually fit the bill. But, because this is a coding challenge, we prefer to avoid using modules that do the work you're supposed to do.

In fact, not doing anything special will check the division by zero, as shown in these one-liners:

Not sure if this has been posted on here on blogs...

https://www.nntp.perl.org/group/perl.perl5.porters/2019/10/msg256484.html

Well the first thing for my S3 todo fixes was to get everything back up to github for my fix for 'GetBucketLocation' once that was done I decided to tackle the rest of the 'todo' tests.

I started out with 'GetBucketPolicy' but I notices that when I set up a real test for the code I get this as the content response;

'content' => '{"Version":"2012-10-17","Id":"S3-Console-Auto-Gen-Policy-1567770368320","Statement":[{"Sid":"S3PolicyStmt-DO-NOT-MODIFY-1567770368320","Effect":"Allow","Principal":{"Service":"s3.amazonaws.com"},"Action":"s3:PutObject","Resource":"arn:aws:s3:::dev.cargotel.storage/*","Condition":{"StringEquals":{"aws:SourceAccount":"985173205561","s3:x-amz-acl":"bucket-owner-full-control"},"ArnLike":{"aws:SourceArn":"arn:aws:s3:::dev.cargotel.storage"}}}]}',

Very odd I am getting JSON back from 'AWS' not 'XML' maybe something has changed ? I think this time on the AWS side of things or maybe my botocode is out of date? I will have to do a little digging.

On the aws site I found this

Response Syntax HTTP/1.1 200

{ Policy in JSON format }

in the latest version of the S# API for the 'GetBucketPolicy'.

The API returns both XML and JSON/Text response!