CodeBuild 2019 or "How I built perl for less than 3 cents"

As part of my Perl/Lambda adventure, I wrote a make-a-perl script that provisioned an EC2 to compile a version of perl. I suspect everyone has their favorite way to compile a perl binary (either for free or not) but here's yet another way to leverage the many tools that AWS has to offer. TIMTOWTDI of course!

CodeBuild 2019 or How I built perl for less than 3 cents

A Perl 6 API for

Untrusted Numeric Input -- /[0-9]/

My blog entry of a couple weeks ago, Untrusted Numeric Input, dealt mainly with the problem of ensuring that supposedly-numeric input actually consisted only of ASCII digits. One of the ways to do this was to use the bracketed character class [0-9] instead of \d. This was documented as being portable as of Perl 5.21.5, and I made the statement that "I believe this behavior goes back further ..." This was clearly just hopeful hand-waving, and not very helpful.

This blog post documents my efforts to try to quantify the versions of Perl under which [0-9] is portable. For those disinclined to read further, my conclusion is that [A-Z], [a-z], [0-9], and their sub-ranges are portable among character sets as far back as Perl 5.8.0.

Pull Request Tracker

Ever since, I submitted the 1500th Pull Request at the end of last year, I have been thinking of doing some kind of data analysis. I love playing with data as it can tell you something interesting every time you poke. I had so many questions in my head with regard to my PR journey e.g. How many authors I have contacted so far? How many distributions on GitHub I have submitted PR against? etc.

Luckily, I have been collecting data about every PR (nearly) that I have submitted so far with details like author, distribution name and pull request id. I have used that in the graph that I have on my personal website.

Pull Request Summary

Yearly/Monthly Breakdown

Swiss Perl Workshop 2019 - Choose The Dates!

We are chuffed to announce The Swiss Perl Workshop 2019. This year the workshop will return to Olten, the venue that hosted the workshop in both 2014 and 2015. The workshop will be held in English, although of course other languages are welcome.

We are yet to decide on a date and have three options:

  • Friday 16th and Saturday 17th August 2019 (one week after TPC in Riga)
  • Friday 4th and Saturday 5th October 2019
  • Friday 11th and Saturday 12th October 2019

We have decided to take the Swiss approach and ask the people. So if you plan to attend this year's Swiss Perl Workshop please let us know which date you would prefer using either this link or the embedded poll below. The survey will remain open until the end of February.

Please spread the word, register, submit talks, and come enjoy a perl workshop in the cosy Flörli Olten.

We are looking for more sponsors. Interested? Please check the sponsoring page.

A Perl 6 API for (

AWS Lambdas & Perl Teaser

Just pushed version 0.0.1 of a framework for creating Perl Lambdas. Sort of a POC and WIP...comments welcome.

Screenshot 2019-02-02 at 3.52.15 AM.png

Git Repo in Shared Hosting #4 - Git Full Service Via SSH

In this fourth article we will now use SSH connection and SSH public keys to give access and also limit access to our repositories.

Monthly Report - January

My start of the year 2019 wasn't very good. I welcome the new year with Flu, suffered till nearly the end of the month. One thing I missed last month was "Pull Request Challenge". No more email from Neil Bowers with random distribution for the month. Thanks to "Pull Request Club", I was still able to contribute.

Let's take a quick look through.

  • Pull Request
  • Git Commits
  • Pull Request Club
  • Perl Blog
  • PerlWeekly Newsletter
  • Adopt CPAN Module

Pull Request

65 Pull Requests submitted in the month of January.

1518 Pull Request altogether.

Git Commits

491 commits recorded in the month of January.

Overall 491 commits recorded so far in the year 2019.

Pull Request Club

Last month, I received OPAR and I submitted 1 Pull Request. It has already been accepted and merged by the author Renee Baecker.

Perl Blog

Last month, I blogged about the following topics.

PerlWeekly Newsletter

Last month, I prepared 2 editions of The PerlWeekly newsletter i.e. Issue 390 and Issue 392.

Adopt CPAN Module


Be the first to author a Perl HTTP/3, QUIC, or QPACK library

This is a public service announcement.

By now, everyone has heard that HTTP/3 is coming. Based on Google's QUIC protocol that began as an experiment circa 2012, IETF QUIC and HTTP/3 are likely to become standards this year.

My employer, LiteSpeed Technologies, has been actively participating in the standardization process. We have also open-sourced several of our C libraries, QUIC Client and QPACK among them.

It would be cool if Perl were one of the first to get its own HTTP/3 or QPACK library. This is a call for a volunteer -- someone who is looking for a new project that is sure to get a lot of mileage. I would be glad to help augment our libraries to facilitate this process.

- Dmitri.

I'm not positive about this...

I'm not positive about this, but I'm not sure that things are behaving as I would expect. What would you expect the following lines to output?

perl -E 'say "x"; say -"x"; say -"-x"; say -"+x";'

For me, lines 1 and 2 make sense. Lines 3 and 4 are different than I would expect, but I'm not sure that they are really wrong. Does somebody want to explain what is really happening, and why it is that way?

Exploring Type::Tiny Part 7: Creating a Type Library with Type::Library

Type::Tiny is probably best known as a way of having Moose-like type constraints in Moo, but it can be used for so much more. This is the seventh in a series of posts showing other things you can use Type::Tiny for. This article along with the earlier ones in the series can be found on my blog and in the Cool Uses for Perl section of PerlMonks.

For small projects, the type constraints in Types::Standard and other CPAN type libraries are probably enough to satisfy your needs. You can do things like:

   use Types::Common::Numeric qw(PositiveInt);
   has user_id => (
      is   => 'ro',
      isa  => PositiveInt,

Slides: A Website for Yancy

I gave a talk this month to Chicago Perl Mongers about the Mojolicious web framework, the Yancy CMS, the PODViewer plugin, and the Mojolicious export command. The talk introduces a simple Mojolicious::Lite application, and adding Yancy to edit the website's content inside the app. Then I explain how to make layout templates, and how to export a dynamic website as static HTML files.

This talk comes from my series of blog posts for the 2018 Mojolicious Advent Calendar: A Website For Yancy, A View To A POD, and You Only Export Twice.

Slides for the talk are available on my website

bless is good parts of Perl language

Recently I feel bless is good parts of Perl language strongly.

Improving Perl debugger variable output

TL;DR: Drop my .perldb file in your home directory for a much nicer debugger experience.

The kindest thing I can say about the built-in Perl debugger is that it doesn't drink even though it's old enough to. Using it is painful but there are many things you can do to make it nicer. Heck, I even had syntax highlighting working once.

One of my major pet peeves with the debugger has been how it dumps variable data. Have you ever used it and typed "x $dbic_object" or "r" to return from a method and gotten hundreds of lines of near useless output spewing across the screen? To make matters worse, it takes a long time to dump all of that, making the slow debugger even slower than normal. It's very frustrating. Here's how to fix it.

When running the debugger, Perl loads a script named and internally, when it needs to dump some variables to the terminal, it runs some code which looks like this (edited for clarity):

Exploring Type::Tiny Part 6: Some Interesting Type Libraries

Type::Tiny is probably best known as a way of having Moose-like type constraints in Moo, but it can be used for so much more. This is the sixth in a series of posts showing other things you can use Type::Tiny for. This article along with the earlier ones in the series can be found on my blog and in the Cool Uses for Perl section of PerlMonks.

While Types::Standard provides all the type constraints Moose users will be familiar with (and a few more) there are other type libraries you can use instead of or as well as Types::Standard.

Sparrow moves to Perl6

sparrow logo


For those whom it may concerns Sparrow announces move to Perl6. I've have started the reddit thread to explain what and why.

Thank you



Exciting news!

Team RPerl will be in Brussels, Belgium two weeks from now for FOSDEM 2019, the largest open source computer conference in Europe (and possibly the world). We will be present the whole weekend, helping out at the Perl booth and promoting the RPerl compiler.

Also, RPerl founder Will Braswell is scheduled as one of the main track FOSDEM speakers, on Sunday February 3rd at 2pm. His topic will be Perl 11, a philosophy that promotes Perl projects aiming to re-unify Perl 5 and Perl 6. RPerl is one such project, and there are several others as well.

You can already read more about Perl 11 in Will's interview for FOSDEM:

We are looking forward to be there, meeting new people, and seeing familiar faces again!


Untrusted Numeric Input

David Farrell's article Validating untrusted input: numbers got me thinking, specifically about the role of \d in sanitizing input. I am not going to talk here about looks_like_number(), because the referenced article covers it.

The thing is, on any Perl recent enough to be Unicode-aware, \d matches digits, whether or not they are ASCII. This may be a problem if you are sanitizing data for numeric conversion, because typically conversion routines expect ASCII digits. There seem to me to be at least two ways to deal with this: restrict your regexp patterns to ASCII, or have the conversion routine deal with the full range of unicode digits.

Restrict Patterns to ASCII

If you truly want ASCII digits for your system, there are a number of ways to restrict a regular expression pattern to ASCII.

Use two-level validation, a.k.a. brute force

By this I simply mean explicitly validating anything that matched \d by also matching it against [:ascii:] in a second regular expression.

Use [0-9] instead of \d

(Mis) Using Perl 6 Grammars : Decompressing Zelda 3 GFX

(Mis) Using Perl 6 Grammars : Decompressing Zelda 3 GFX

Grammars combined with actions allows to parse strings and produce something from it. It's not far fetched to say that any compressed data follow a structure that is likely 'parsed' by the corresponding decompression algorithm.

So why not using Perl 6 grammar for this kind of work? Especially a compression I am familiar with.

A look into Nintendo compression

Nintendo used the same base compression format for their SNES games with some variant depending on the game. It's pretty straight forward and it's easy on the ~2Mhz of the SNES CPU.

It goes like that:

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