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These are some answers to the Week 39 of the Perl Weekly Challence organized by Mohammad S. Anwar.

Spoiler Alert: This weekly challenge deadline is due in a couple of days (December 22, 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.

Task # 1: Guest House

A guest house had a policy that the light remain ON as long as the at least one guest is in the house. There is guest book which tracks all guest in/out time. Write a script to find out how long in minutes the light were ON.

The guest book looks as follows:

I'm already working on Part II, but here's Part I in all its glory: http://www.theperlfisher.com/index.php/2019/11/24/rewriting-legacy-code-for-raku/ - I'm writing OLE::Storage_Lite from the original Perl 5 source, and this article series is my thoughts on the process so far.

The Encoder

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

Before we can encode Morse code into its binary representation, we need to encode normal text into Morse code. As a former Woodcraft member, I was able to write the following lines by heart:

my %to_morse = qw( a .-   b -... c -.-. d -..  e .    f ..-. g --.
                   h .... i ..   j .--- k -.-  l .-.. m --   n -.
                   o ---  p .--. q --.- r .-.  s ...  t -    u ..-
                   v ...- w .--  x -..- y -.-- z --.. );

The encoding subroutine is straightforward: split each word into separate characters, then replace each with the value from the above hash.

sub encode_to_morse {
    join '/', map $to_morse{$_} // "", split //, shift
}

Note that space is not present in the translation table, so it gets translated to an empty string, which creates the expected double slashes between words.

Well still in clean-up mode here in the Paws Pen trying to get the full t/10_response.t test case working.

I was having all sorts of fun with the 'GetBucketPolicy' action test. By fun I mean a good hour of frustration and cursing and gnashing of teeth as my real-time test script was working fine! I just could not get the test in 's3-get-bucket-policy.response.test.yml' to pass.

Then I stumbled on it.

This is the one very odd action on the AWS S3 API where it dose not return XML but returns JSON. Now I do handle this with this code

       } elsif (exists($headers->{'content-type'})
               and $headers->{'content-type'} eq 'application/json'
               and $ret_class->can('_payload')){
        $unserialized_struct->{$ret_class->_payload} = $content;

in RestXMLResponse.pm.

These are some answers to the Week 38 of the Perl Weekly Challenge organized by Mohammad S. Anwar.

Challenge # 1: Date Finder

Create a script to accept a 7 digits number, where the first number can only be 1 or 2. The second and third digits can be anything 0-9. The fourth and fifth digits corresponds to the month i.e. 01,02,03…,11,12. And the last 2 digits represents the days in the month i.e. 01,02,03….29,30,31. Your script should validate if the given number is valid as per the rule and then convert into human readable format date.

Rules:

1) If 1st digit is 1, then prepend 20 otherwise 19 to the 2nd and 3rd digits to make it 4-digits year.

2) The 4th and 5th digits together should be a valid month.

3) The 6th and 7th digits together should be a valid day for the above month.

For example, the given number is 2230120, it should print 1923-01-20.

Benefits

What benefits Perl provide to users?

Target

Who is the Perl user?

Strength

What are the strengths of Perl?

Place

Where do people find Perl?

These are the basic elements of Marketing.

Here is my plan for 2020:

https://perlweeklychallenge.org/blog/plan-2020/

Platypus is getting an update. It’s not backward compatible, so you have to opt-in when you create the platypus instance. That makes it backward compatible for all the old code you may or may not have written. Please spread the word.

# old code:
use FFI::Platypus;
my $ffi = FFI::Platypus->new;

# new code:
use FFI::Platypus 1.00;
my $ffi = FFI::Platypus->new( api => 1 );

You should generally write all new code using the new API so that you can take advantage of the newer features and design fixes. You may want to also consider upgrading your existing code to use the new API for the same reasons.

These are some answers to the Week 37 of the Perl Weekly Challenge organized by Mohammad S. Anwar.

Spoiler Alert: This weekly challenge deadline is due in a couple of days (December 8, 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: Week Days in Each Month

Write a script to calculate the total number of weekdays (Mon-Fri) in each month of the year 2019.

Well today on paws I figured I would take a look and see what was outstanding in terms of code to fix. All that I could find was only really one thing and this boto fix well really a Kludge

/{Bucket}?action
/{Bucket}?action&id={Id}

where I add the id to the URI to get around a bug/problems when running this code on RestXmlCaller.pm;

$uri->query_form(%$qparams); 

would scramble the URI so the call would fail.

What I would like to do is roll back the changes I have made for Boto and see if I can find a pure Perl solution to my problem.

Slices

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

In the spirit of TIMTOWTDI I decided to write a single program that demonstrates both the tasks at the same time.

Let’s start with slices. Slices are parts of structures (arrays and hashes). Slicing has a special syntax by which you tell Perl which indices or keys you want to use to obtain a slice.

For example, consider the following array:

my @keys = qw( not_this_one
               this_one
               this_one_too
               it_was_enough );

Naturally, we want to select the second and third one. We can use

$keys[1], $keys[2]

or

map $keys[$_], 1, 2;

but there’s a shorter and cleaner syntax for the same:

@keys[1, 2]

The LedgerSMB project aims to prevent small and mid-size businesses from getting locked-in by their accounting software vendor by providing free and open source accounting software, integrating invoicing, order processing, quotations and more (ERP). It's all Perl!

Having installed it myself, I found it very very fully featured. You can try out their demo and watch one of their numerous youtube intros and tutorials

The LedgerSMB development team has announced release 1.7.3.

This release contains the following fixes and improvements:

Changelog for 1.7.3

Releases for stable branches of 1.6.15 and 1.5.29 have also been released.

The project has an official Docker image, tar balls, and deb packages all detailed on their downloads page.

These are some answers to the Week 36 of the Perl Weekly Challenge organized by Mohammad S. Anwar.

Task # 1: Vehicle Identification Numbers (VIN)

Write a program to validate given Vehicle Identification Number (VIN). For more information, please checkout wikipedia.

From the Wikipedia article, it appears that VINs are made up of 17 digits and upper-case letters, with the exception of letters I (i), O (o) and Q (q), to avoid confusion with numerals 0, 1, and 9. There are some additional rules that only applicable to certain areas of the world but are not internationally recognized.

Vehicle Identification Numbers in Perl 5

We write a simple validate subroutine that returns a true value (1) if the passed parameter complies with the above rules for VINs and a false value (0) otherwise.

Well today’s post marks a tuning point in Paws me thinks, at least in the S3 name-space. I have been spending quite allot of time trying to get this action to work;

PutBucketAcl

It is the most nasty bit of AWS code I have come across so far. First one needs to send this XML up to AWS;

<AccessControlPolicy xmlns="http://s3.amazonaws.com/doc/2006-03-01/">
  <Owner>
    <ID>852b113e7a2f25102679df27bb0ae12b3f85be6BucketOwnerCanonicalUserID</ID>
    <DisplayName>OwnerDisplayName</DisplayName>
  </Owner>
  <AccessControlList>
    <Grant>
      <Grantee xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:type="CanonicalUser">
        <ID>852b113e7a2f25102679df27bb0ae12b3f85be6BucketOwnerCanonicalUserID</ID>
        <DisplayName>OwnerDisplayName</DisplayName>
      </Grantee>
      <Permission>FULL_CONTROL</Permission>
    </Grant>

You will notice that in the 'Grantee' tag there are some XML attributes!!. Sure enough it is in boto JSON

Would you like to get one user instead of the top of TIBOE?

TIBOE provides rankings with a biased perspective.

A few leading engineers understand that TIBOE has no value

Many dishonest media continue to introduce TIBOE ranking.

Rather than getting the top of the biased ranking,

Wouldn't it be better to get one excellent and sincere engineer?

Marketing is not to mislead people.

Low quality marketing is done around the world, but there is no reason for Perl users to join it.

High quality marketing looks at the mind of a one user.

I missed this release but it's only a little over a month old, so its still news.

Sympa 6.2.48 is the newest stable version of Sympa 6.2.

Sympa is an electronic mailing list manager. It is used to automate list management functions such as subscription, moderation and management of archives. Sympa also manages sending of messages to the lists, and makes it possible to reduce the load on the system. Provided that you have enough memory on your system, Sympa is especially well adapted for big lists. For a list with 20 000 subscribers, it takes 5 minutes to send a message to 90% of subscribers, of course considering that the network is available. Check out the full list of features.

From the release notices

• Data sources: Codebase has entirely been rewritten. It will work a bit faster with less memory usage in exchange for some changes on behaviors.
• Perl: From now on, Perl earlier than 5.10.1 will never be supported.

The full Change Log is here.

RPM Packages are in Fedora and EPEL, and Sympa is in the FreeBSD ports tree. Otherwise you can just install from source tar ball.

Also, a new Logo for the project has been proposed. Check it out too.

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.

"keep_root":true 

I stumbled upon this when I added in a few fixed cases from another branch and when I ran the suite I
got;

ok 10052 - Call S3->GetBucketLocation from t/10_responses/s3-get-bucket-location.response not ok 10053 - Can't test method access because something went horribly wrong in the call to GetBucketLocation # TODO t/10_responses/s3-get-bucket-location.response.test.yml

My present output of the call is

On October 22nd I was interviewed by Dave Rael for Developer On Fire podcast.

It has been an interesting experience, and Dave has been a great host making me feel very comfortable during the whole process.

I talked about Open Source, archery, cats and PostgreSQL.
Here there is something more to read about, and for listening the interview just click on the image.

Devel::PPPort 3.55 has more than two hundred commits since the last major releases. The documentation has been extensively revised to make it clearer how to use, and to contribute. And it has been updated to know about the latest blead; the first such update in 5 or more years.

Dozens of functions and macros are newly implemented. The suite of SV handling functions is more complete, with more flags handled. Also the character classification macros (alpha, punct, etc) and case changing functions are greatly expanded. There is more Unicode support, including modern security standards.

ppport.h --api-info foo

is much more complete than before. If you make 'foo' to instead be '/./' you'll get information about every known API element.

And it still supports 5.003, with a surprising number of elements functioning that far back.

The full documentation is available at .

The version backporting is valid for is unknown for quite a few API elements. That is because documentation is lacking on the parameters these take, and so the automatic tests for these elements can't be generated. If you know what some of the missing things do, we would greatly appreciate your contributing documentation for them. in the form of a github pull request.