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[From the YAPC::NA Blog.]

• Will this script run under the Perl version available to the customer?
• What Modules can I use for the work?

tyler@inspiron:~$ perl -v 
This is perl, v5.10.1 (*) built for x86_64-linux-gnu-thread-multi

I have found that Perl 5.8.x is the most common distribution available on all servers I have worked with. So, how to make sure the code I write will not break on a 5.8.x Interpreter?

A few weeks ago I was asked if I'd be interested in re-making the after5detroit.com website. The interface had already been mocked up in Adobe Illustrator and the front-end/back-end design and architecture was still available for the taking. I of course took the gig. I was looking for an excuse to work on something new anyway.

Mojolicious::Lite, DBIx::Class and the Dojo Toolkit are my tools for this endeavor. I've been working with them for the past couple of years now and enjoy every minute of it (usually).

Sadly this is a paying gig so I can't share the code with any of you. But if I can pull something reusable out of it I'll see what I can do.

More to follow, I've got 6 weeks...

I've just decided to spend a couple of hours tidying up my CPAN projects - surprising how little you can get done in an evening if you let things slip.. on the plus side, I've made a start and cleaned things up a bit :

• Autodia page on my personal site now updated to point to latest version on metacpan, and files to svn trunk
• Several bugs marked resolved, and updated, spam delete in rt.cpan.org
• Emailed Smylers about consolidating the various GraphViz::DBI forks on cpan using some shared co-maint and github (anyone else interested give me a buzz)
• Tidied up Graphviz::SQL and Math::Curve::Hilbert a bit and put them in github.

My Plan is to mark any bugs older than 5 years or for very old version of my cpan modules as stalled or won't fix and then get on top of what's left - all my CPAN modules are being moved into github too.

No code written this evening, but definitely useful time spent.

It’s the first Tuesday of the month, so that means it’s YAPC::NA Planning Meeting time. If you’re in the Madison area, or don’t mind a drive there is a YAPC planning meeting tonight at the Essen Haus at 7pm. As always the food and beer are sponsored by Plain Black, and the room is sponsored by Essen Haus.

We’ve got a lot to discuss so the meeting will probably last until around 9pm, but you’re free to come and go as you please.

[From the YAPC::NA Blog.]

Today, I tried to test a freshly created DB schema using Test::DBIx::Class. Scanning through the documentation was impossible -- it knows far too many options to get captured within a few minutes. But carefully reading the brilliant manual is worth the time spent. Test::DBIx::Class has a lot of options and test-functions tailored especially to the needs of DB-testing.

My primitive schema knows 3 tables: Sensors, Measures and AlarmConditions. Inside my t/ directory, I needed to create only one supplementary file to allow the tests to get coded: a config file t/etc/schema.pl

{
    schema_class => 'Statistics::EasySchema',
    force_drop_table => 1,
    resultsets => [ qw(AlarmCondition Measure Sensor) ],
    connect_info => ['DBI:Pg:dbname=statistics_test', 'user', 'secret'],
}

1. You have: a PDF containing about 10.000 pages.
2. You need: a file that can be sent to your printer (Postscript, PCL, whatever)

with the help of ingydotnet++ valuable suggestions, Mo now has the option to chain accessors:

package ChainedAccessors;
use Mo qw/chain/;

has 'first'  => (chain => 1);
has 'second' => (chain => 1);


package main;

$f = ChainedAccessors->new;

$f->first(1)->second(2);

$f->first;  # 1
$f->second; # 2

thanks also for the feedback in response to my previous blog post

We are now accepting talk proposals for YAPC::NA 2012. 

We’re of course interested in anything Perl-related you want to talk about. However, we have two areas we’re definitely interested in:

First, we’re looking for talks on Perl in the Wild. These talks are about businesses and individuals who have done great things with Perl. Perhaps you’ve automated your house with Perl, or built the latest and greatest web app. Or maybe you’re controlling Arduino boards to build robots with Perl. Maybe you’ve got amazing case studies in high-end performance with Perl. Or maybe, you’ve built a boring little app in Perl that has enabled your business to make millions of dollars. You could be building a great video game in Perl, or perhaps a social network to take down Facebook and Twitter.  Whatever it is that you’ve built or are building, we want to hear about it.

I published my first blog on 29th Sep'2011 about how Dancer and Rose::DB can be used together to build a web app in no time. Here is the link to that blog, if you have missed it.

I have been thinking of improving on that and first thing that came to my mind is how about adding pagination feature while displaying the items. There are many gems available on CPAN to help you in pagination. However I was looking for something that is easy to plug in with my Dancer web app. In my research I came across an example doing exactly what I was looking, although I find it incomplete by Alexis Sukrieh. Here is the link to that code.

I grabbed the idea from the above example and incorporated into my Dancer web app that I wrote as a part of my first blog. Here is the link to the code, in case you are looking for.

I am going to add this to my public github repository very soon.

In the previous post in this series, I described the way the Traditional Perl Parser (TPP) parses Perl's use statement. This post will describe an IMHO attractive alternative approach, using my own Marpa::XS. Marpa::XS has a prototype Perl parser as part of its test suite.

The TPP Way

If that previous post is not fresh in your mind, it may be useful at this point to look back at it. Summarizing, the TPP uses the "Ruby Slippers" method: It first simplifies the grammar so that, while convenient for the parser, the grammar falls short of describing the actual language. The lexer then fakes the input to the parser so that the parser's "wishful thinking" comes true.

In the TPP, the parser requires all use statements take this form:

use_statement ::= USE WORD WORD LIST

The Marpa::Perl Way

Firstly I would like to mention that I have just released version 0.06 of Math::GSLx::ODEIV2. For those of you who aren’t familiar with it (most of you I’m sure) this module represents a Perl-ish interface to the new GSL ordinary differential equation solver.

The major improvement of this version of my Perl module is the handling the Jacobian of the ode system. This allows the use all of the step functions in the original C library. In fact, other than one small feature that I would like to add (specifying quantity specific error limits), the module is just about feature complete.

Welcome to 2012. You made it! Can you believe it? I can't believe it either, the way you partied last night. Have you no shame?

Well it's time to make a New Year's resolution. You're coming to YAPC::NA 2012 in Madison, WI on June 13-15. 

While you're at it, have your spouse or significant other make the resolution with you. Bring them to the YAPC::NA 2012 Spouses Program.

Recently I needed something with the same functionality of Data::Dumper but prettier printing for dealing with nested structures. First stop Metacpan. I type in 'Data::Dumper' and the auto complete dropdown lists some suggestions and I try a few. Ovid's Data::Dumper::Names gives me the names of variables I pass in by reference. With Data::Dumper you would see this

$VAR2 = [ 
          [ 
            'plain', 
            'white' 
          ]
        ];

September has turned out to have been a very difficult and traumatic month for CPAN Testers. Our server problems have now been resolved, but it has meant more time than was intended has been devoted to rebuilding the website eco-system. It's still not complete, but we are getting there.

The first sites to be reinstated were the CPAN and BACKPAN mirrors. Soon after the Statistics site and Development sites were back online. The database rebuilds took considerably longer than expected, partly because the archive of the original NNTP reports had become corrupted at some point. The checks to ensure all interconnected parts of the databases were correctly referenced also took time. A full backup was then taken so we could start from a known point once all the moving parts were restarted. Just in case anything went wrong again!

Next time I upgrade DBIx::Class it will probably tell me I need to get a haircut.

DBIx::Class::Schema::connection(): You provided explicit AutoCommit => 0 in your connection_info. This is almost universally a bad idea (see the footnotes of DBIx::Class::Storage::DBI for more info). If you still want to do this you can set $ENV{DBIC_UNSAFE_AUTOCOMMIT_OK} to disable this warning. at lib/Territory/Model/TerritoryDB.pm line 23

Did you know that YAPC::NA has a mailing list? Neither did I until a couple days ago. Starting now, I'll be cross posting our news items to the mailing list, in case that is your preferred way to receive news about YAPC::NA 2012.

(*STORE,*TIESCALAR)=
  map{eval"sub{$_}"}qw'map{print&&sleep$|}split//,pop bless\$|++';
tie$t,main;$t="Just another Perl hacker,\n"

I have been blogging for some time over at http://joelslinux.blogspot.com. It was and still will be a blog about Linux and the open source software that I use. I doubt it has many readers, in fact it was mostly for me to remember interesting tidbits should I need them again.

In the past few years I have become quite a Perl enthusiast, doing most of my day-to-day work in Perl and authoring several modules. To get a little deeper into the fray I decided to split my blogging, posting on Perl here in case it may be of use to anyone. I hope people find it informative and I hope to get feedback from those who do (or don’t for that matter).

Hope to see you at the Pittsburgh Perl Workshop.

Recently, I created a new issue on Github for Mo (https://github.com/ingydotnet/mo-pm), suggesting a chained interface: