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system seems like such a simple thing to use. You tell it which command to run, and it runs it. When it's done, you continue with your program, or so you think. I recently ran into a problem with this. I was creating a lot of zombies, but Dread Pirate Fenwick to the rescue (and this is not his first time to rescue me).

As part of my DPAN work, I'm indexing every distribution in BackPAN. I collect loads of data on every distribution so I can make a searchable catalog of it. When you want to use DPAN to create private CPAN repositories, you shouldn't have to re-index distributions where we already know the answer. I can provide most of the answers pre-cataloged so you focus on only the novel distributions in your repository. I have a tarball of sample results for 16,000 distributions.

Adam Kennedy has declared a contest between Dancer and Mojolicious. Seems to me like a great idea. We'll both get a chance to learn from each other, show our strengths and try to work on our exposed weaknesses.

One major issue about Mojolicious is that they decided to do everything in core (at least from perl 5.10.1), without any additional dependencies that aren't in Perl core (while, we at Dancer, try to keep the dependencies to a minimum). This has many disadvantages (reinventing the wheel, handling the same issues over and over, needing a lot of knowledge on how to implement everything) and a lot of advantages (easier deployment, easier packaging for vendors, more control). This post is about one of those advantages.

# http://search.cpan.org/perldoc?DBIx::Class::ResultSet#cache
my $rs = $schema->resultset('Artist')->search(
    {},
    { cache => 1 },
);
my @artists = $rs->all;
pop (@artists);
$rs->set_cache(\@artists);

my $count1 = $rs->count;
my $count2 = scalar $rs->all;
my $count3 = scalar $rs->get_column('id')->all;

Q1: What are the values of $count1, $count2 and $count3?

A1: 9, 9, 10.

Q2: Why?

A2: $rs is a cached result set. Some methods on $rs return the cached results. Some don't and query the underlying db table(s).

Q3: Which ones do & which ones don't?

I've always liked Prolog as a programming language. Something about the way the language works (like the built-in backtracking) appeals to my nature, much like Perl's proclivity for linguistic floridity. Thus, I've decided to try my hand at writing a Prolog compiler for the Parrot VM.

To try to suppress my natural tendency to move from subject to subject (being a fox and not a hedgehog) I'm going to keep a development diary here. Also, I've found that the documentation on implementing HLLs with Parrot is either thin on the ground or a bit dated. So hopefully some of my scribblings turn out to be useful to someone else.

I've started work on the project, and keep a repository on GitHub. If you're interested, have a look at http://github.com/arnsholt/parrotlog.

I upset a lot of people with my Perl 5 is Dying post. In fact, that is far and away one of the most heavily cited posts I have. I made people mad at me. I made a lot of people talk. While I'm sorry I made people mad (and I've had some blunt comments directed at me in pubs as a result), I'm very proud of that post. It got a lot of people arguing and thinking and I like to believe it spurred a few people (well, me at least) to do something about it. Here are just a few things which have been happening to turn things around (I am not taking credit for this. Many of these things would have happened any way and I was simply one of many people pointing out the problem).

I just saw this posting about the best Perl development firm. There is an entry on Online PR news and some kind of a listing on the website of "Best Web Design Agencies".

Does anyone know any of these companies or is this just pure SEO and I just gave them more ranking?

According to git log I've submitted 33 patches to perl core, I just submitted another one which on Linux changes this:

Into this:

If this patch gets applied doing killall onion on 5.14 will get you a dead process instead of onion: no process found, the same goes for ps(1) and top(1) which read the legacy process name by default. Before this patch the behavior of $0 assignment on Linux hadn't changed since perl 4.000 came out.

It appears that there was a touch of confusion and I have been accepted as a speaker at OSCON. I'll be giving the roles talk, but with some adjustments for bits that were a touch confusing. No matter how perfect the example is, using the B:: hierarchy to show multiple inheritance problems just distracts. Not only will this allow me to focus on easier examples, it will also leave more time for questions.

I used to encourage people to help CPAN Increase its Schwartz by making the ratio of the byte size of just the latest versions to all versions as high as possible. It's time to increase the schwartz again. Think of it as Spring cleaning (Autumn for you southern folks) for your CPAN directory.

Many people are arguing on the CPAN workers mailing list about who's opinion about rsyncing mirrors is the most worthy. While they huff and puff, you can help with just a couple minutes of your time.

... Replaced by the superior App::SVN::Bisect by Infinoid.

Infinoid's svn-bisect, now at 1.0, provides a 'run' option, just like git bisect. This is the only feature I had that he did not, and he provides many more, including a nicer API (based on git's), and smarter binary search (only searching those revisions involved in the folder you're working in.)

If you're using subversion, I highly recommend giving his tool a try.

Scheduling App::SVN::Bisect for deletion now...

DynaLoader is a portable high-level interface around you OS's dynamic library loading. It's the code that's loading your XS modules. It's actually doing a pretty good job at that. You may wonder then why I consider its use harmful.

If all you want to do is load the XS part of your module, it's the wrong tool for the job. Most of all because it has a truly awful interface. It requires you to inherit your module from it. It's common knowledge that public inheritance from an implementation detail is a really bad idea. It breaks not only encapsulation rather badly, but also violates separation of concerns.

This would be as bad as it is if DynaLoader didn't use AutoLoader. Because of this, when you call some undefined method on an instance of a class that derives from DynaLoader you don't get this error:

Can't locate object method "undefined_method" via package "Foo"

But this rather cryptic error:

Today having Internet access has become more of a necessity than a luxe. Internet is so common nowadays that we all have it at home and use it with all computers and even our home appliances: tv, mp3 players, tablets and game consoles. It's no sercert that Internet is everywhere and is here to stay

I remember when I had my first Internet connection at home that it was meant to be used for a single computer in the house. Using a router was not allowed by my ISP. Today not only is it allowed but most ISP even provide a modem/router with WIFI to all their clients!

First off, I'd like to thank God (the whole Earth is filled with his glory) for this promotion. I was just a Seraph, doing my normal PR work, but somehow God (holy, holy, holy and all that) noticed me and decided it was time to give me a bit more responsibility. Of course, being untested, he couldn't put me in charge of something as important as the US Senate or something like that, so he gave me Africa. After all, if I screw up there, who's going to notice? Naturally, I screwed up. I saw something wrong and I decided to fix it.

Marpa::HTML is a high-level HTML parser, built on top of the very high-quality HTML::Parser module. Why bother with high-level parsing, especially if it means layering one parser on top of another?

Here is an example, taken from the main document for HTML::Parser. The example prints out the title of an HTML document. To do this, HTML::Parser uses handlers which set up other handlers. One handler finds the start tag, then sets up two other handlers. (I won't reproduce that example here -- it's on CPAN. )

The hackathon will start in ~ 2 weeks, so here's a quick update on our status:

• We have a new sponsor: 123people.com. Yay! pst++
• Unfortunately David Golden, Ricardo Signes and Barbie can not make it.
• We accepted two last-minute requests from Miyagawa‎ and Gabor Szabo.
• There was a tiny problem with the hotel, which luckily got spotted by Ovid. We have fixed that problem now.
• We will meet next week (during the monthly Vienna.pm meeting which will from now on take place on the first Thursday each month) to discuss the agenda etc.

We're all very much looking forward to the event!

http://www.slideshare.net/redhotpenguin/dfv-3542204

Both of my proposals for OSCON were turned down, so I won't be able to make it this year. The BBC is also feeling the financial crunch, so international conferences are harder to manage. I'm not terribly disappointed, but it would have been nice to see my beloved Portland again. Fortunately, with my wedding in June, a number of my close friends from Portland will be in London. If you can't bring Ovid to Portland, bring Portland to Ovid.

On the plus side, I think this means I'll be able to attend YAPC::EU in Pisa. It will be nice to spend a bit more time in that city. My Pisa photos are sorely lacking.

In addition to The Perl Foundation being accepted into GSoC 2010, BioPerl is now also part of the Google Summer of Code! The Open Bioinformatics Foundation, which also includes BioPython, BioRuby, and others, has been accepted into the Google Summer of Code for 2010. We are actively looking for students interested in OBF-related bioinformatics projects; new ideas are welcome. Project ideas and other details can be found here:

• Main OBF GSoC page
• BioPerl-specific projects

This isn't the first year BioPerl has been part of GSoC. A successful project was recently published by 2008 GSoC student Mira Han for developing a phyloXML parser for BioPerl.

Update: Rough project idea for use of Modern Perl tools or Perl 6 with BioPerl now added.

The Perl Foundation is participating in Google Summer of Code 2010 and will begin accepting applications from students on the 29th.

If you are a college student interested in Open Source software, now is the time to get involved.

http://code.google.com/soc/

Each year, Google offers students the opportunity to spend their summer coding on open source projects. You propose a project, and if selected, you're assigned a mentor and provided a $4500 stipend. It is a competitive program to get into, but offers an amazing amount of real-world experience and the ability to get seriously involved in an open source project of your choosing. The Perl Foundation spans a wide variety of projects including Perl 5, Perl 6, and Parrot with many great mentors knowledgeable in areas ranging from language design, virtual machines, and compilers through web and desktop applications. This program is a great chance to get more involved in the Perl community and put a substantial project worth of source code in your portfolio.

Applications are due April 9th.

http://www.perlfoundation.org/perl5/index.cgi?gsoc