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The installation of Movable Type on this site was a couple[1] of versions behind so last night I decided to update the site to version 4.37.

Unfortunately, while carrying out the update, I skipped a vital step. I forgot to copy over the many site specific plugins which are installed here. This meant that for approximately ten hours overnight (UK time) the site was broken and it was impossible to create new blog entries or to post comments.

I think the problem has been fixed and the site should now be back to normal.

Apologies for the problems. I'll be more careful next time.

If you see any problems with the site, please report them over on github.

[1] For embarrassingly large values of "couple".

Hi Folks

Yep, both Marpa-style grammars and Set::FA::Element-style state transition tables can now be graphed.

As always, the demo page is the place to start.

After that, hit CPAN.

[This is now [perl #93548]]

Perl 5.14 added a return value to given if you put it inside a do. However, it looks like that return value can't be a value in a lexical variable the you define inside the given:

Some CPAN modules I inherited used the old Test.pm for some of their t/*.t scripts instead of the more modern Test::More. This annoys me to no end because Test.pm is very limited. When I worked on Config-IniFiles, I did the conversion manually, which was a lot of work. More recently, I started working on XML-LibXML which has over 40 of those pesky Test.pm scripts, and I did not have the nerve to do all the manual and menial work.

As a result, I ended up spending a few hours studying PPI (the Perl Parsing Interface), and writing a script to automatically convert Test.pm-based scripts to Test::More. The main issue at hand was that in Test.pm, a single argument ok() tests for the scalar's truth, while a double argument ok() tests for simple equivalence (similarly to Test::More's is()). Eventually, I got the script working, with some limitations (see the page).

The Astro-satpass distribution contains classes to compute satellite position and visibility. If you are using it, please read on. If you think I should continue to deliver change notifications via this blog, please let me know, otherwise I will stop doing so, and merely give notice via electronic mail.

On June 11 2011 I wrote about the changes to the Astro::Coord::ECI::TLE pass() method which were in release 0.039_04. The blog entry detailed those changes and expressed the intent to make another release in about two weeks.

A respondent questioned the performance of the pass() method when the interval attribute was positive. This attribute causes the pass() method to return periodic positions during the pass, as well as the significant events of the pass. Investigation revealed a serious inefficiency in this functionality, and turned up some more “edge case” pass prediction problems.

First, please, you are free to comment, but I do not want to open a flame war or anything. Also, I do not think this is the place for this to be discussed. This post is just my humble opinion.

I think Perl 6 is a bad name for the new language Larry (and Damian and others) are defining. First, before the language, although based on Perl 5, is a new language. Second, because the name is around for too many time, making it bad advertising for the language itself, and for the community. Third, because it makes hard to Perl 5 to advance.

In fact, I think that keeping the name of the new language as Perl 6 is bad for everybody, from the people that do not like Perl 6, for the people who love Perl 6, and for all the community members.

hi there,
Am new to perl. been very determined make some lines of code fromRandal l. Swartz work.
It reads:
write a subroutine named greet, that welcomes the person you name by telling them the name of the last person it greets.

like; greet('fred');
greet('Barney');

This sequence of statement should print:
Hi Fred! you are the first one here!
Hi Barney i've seen Fred
Hi Wilma i;ve seen Fred Barney
HI Betty ive seen Fred Barney Wilma.

I have folloed the tips and even implemented defined operator and state but nothing seem to work. Anyone with extensive knowledge of this should please help me with the answer.

A few days ago we began moving things together to form the conference schedule. It was ready a couple of days ago, and after talking to the speakers and making a number of changes, we are proud to present the schedule to a wider audience.

YAPC::Europe 2011 "Modern Perl" Schedule is publicly available: Monday 15th, Tuesday 16th and Wednesday 17th of August are full of Perl talks.

This year we easily filled four talk tracks for the whole three days of YAPC. The first day even contains five. All the talks start at 10 a.m., and together with the fact that Riga Old Town is small enough, it would be quite convenient for many of us to show up at the conference a bit before 10 in the morning.

The first two days will be opened with the keynotes given by Larry Wall and Damian Conway. The names say everything.

Here's one for the "stupid shell tricks" category:

I made myself a shell alias today to simplify the times when i want a quick view of how something works in perl:

alias perl1='perl -MData::Dumper -MYAML::Any -MClass::Autouse=:superloader -E "sub D(\$){ say Dumper(shift) } sub Y(\$){ say Dump(shift) }"'

I'm not quite sure about the name, and I may add more helper functions, but a handy alias like this one allows me to type this at the shell:

perl1 -E 'D [File::Spec->path]'

Instead of

perl -MData::Dumper -MFile::Spec -E 'say Dumper( [File::Spec->path] )'

I don't have to type out -MData::Dumper and I can use D instead of say Dumper()

Plus, thanks to Class::Autouse and it's :superloader import tag I don't have to type out Module::Name ("File::Spec" for example) multiple times just to get a quick glance at it's output.

I haven't decided yet if I want to just append " -E" to the alias. That might get in the way if I want the "-n" or "-p" flags or multiple -E's or something...

Anyway... thought that was handy; Thought I'd share.

I got tired of seeing my SQL in big, ugly grey walls of text in my Perl code, so I wanted to syntax highlight them. Of course, since I'm working with a large code base which has evolved over many years, it's simply not possible (or desirable) for me to rip these out and replace them with SQL::Abstract or something else (as has already been suggested) lest I spend a few weeks not developing features and hoping I didn't introduce bugs.

Fortunately, vim allows you to be rather flexible about this.

Probably you do not agree with my point of view, but I think that adding version numbers to sub-modules is, most of the times, counter-productive.

Explaining what I mean by adding version numbers to sub-modules. If I have a module, named Foo::Bar that ships with Foo::Bar::Helper, probably I don't want to add a version to Helper module.

Or if you do, be sure to keep or increment it on every release you do.

Why this matters? Well, it matters to the people who use cpan and the r command to check for outdated modules:

CHI::Driver::Role::HasSubcaches     undef      0.45  JSWARTZ/CHI-0.45.tar.gz
CHI::Serializer::JSON         undef      0.43  JSWARTZ/CHI-0.43.tar.gz
CHI::Test::Class              undef      0.39  JSWARTZ/CHI-0.39.tar.gz
Mason::DynamicFilter           undef      2.06  JSWARTZ/Mason-2.06.tar.gz
Mason::Plugin::Defer::Filters     undef      2.01  JSWARTZ/Mason-2.01.tar.gz

Very basic introduction with example about how to use Devel::Cover to improve your tests.

Read the article.

Programs, modules, and distributions are different things, but we are often loose with the language. In CPANizing Behavior and Democratizing Publishing, chromatic conflates two issues that are really only loosely connected: making modules and releasing code as a Perl distribution.

Distributions are merely the unit of things we give away. A Perl distribution has a conventional structure, and usually contains modules. However, there's no requirement that it contain any modules. It doesn't even have to contain Perl code. It's quite easy to distribute a non-module Perl program in a Perl distribution. The major installers handle it just fine. You can even extend the installers right from the distribution, doing almost anything you wanted.

A few days back I stumbled on this blog post about increasing your intelligence and the Dual N Back task

I had a dot cloud invite that I had not used and I wanted to learn some HTML5 and looking around there did not seem to be a N-back version in HTML5 (most of them use flash) so I created a web app Bodhi . The intent is that this app works on the browser as well as mobile devices ( at least iPad). This is the initial version and I am looking for some feedback on improving this or adding some more tasks.

I am pretty impressed with the dot cloud infrastructure, it's easy to get started and deploying is simple.

For some time now, I am a Dancer contributor. It all started in the last Christmas (everything in the Perl community start or end at Christmas time), with Dancer Advent Calendar.

Getting a little behind... I tried to learn to use Catalyst some time ago, reading a Packt Publishing book and found at that time that the book was already outdated. Unfortunately that is standard in Technology, and the books that keep up to date for some time are the ones that focus the foundations of computer science, and not the technology itself. It didn't work. Probably I was not tuned to the MVC model, or I didn't have a concrete project where to test Catalyst.

After a long 3 months or so, Padre 0.86 has been rolled up and released into the wild.

0.86 comes with a warning that there are still some lumps to be smoothed out, but with that it also comes with a newer version of Scintilla which means better support of Perl.

Thanks to the efforts of Ahmad Zawawi and Mark Dootson, who you often see in the Perl Wx mailing list, this version of Padre now supports an updated version of the Scintilla text editor/control. You can enable the new Scintilla by setting the feature_wx_scintilla configuration parameter in Padre's Tools / Preferences / Advanced dialog.

The process of organizing my summer speaking tours is often NP-complete, with too many possible events competing to fit into too few available timeslots.

So it's a refreshing change, this year, to find myself with an entire unused week, during which I definitely need to be in Europe, but could be anywhere in Europe. The week in question is August 7-11 (i.e. the week immediately before YAPC::EU).

Normally I would just arrive at the conference venue a week early, lock myself in my hotel room, and hack for 168 hours straight...but this year I thought I might try something different. So I'm putting out an invitation to the entire European Perl community: make use of me for a week!

The idea is simple: anybody anywhere in Europe is welcome to contact me with a suggestion/proposal for occupying my time from August 7 to August 11.

For a long while, work on the XML-LibXML CPAN module halted as the existing maintainer was busy. After a discussion on the Perl-in-XML mailing list, some people and I were given co-maintainer status and we resumed its maintenance inside a Bitbucket.org Mercurial repository.

So far what I did, was fix some low-hanging fruit bugs, apply some patches, as well as start the long process of converting the test suite, which still uses Test.pm to Test::More . There are still many bugs lurking there, and some of them are XS bugs that are still beyond my reach, and I could use some assistance there. But it's a start.

If you're interested in helping, the clone the repository, write a patch and send me a pull request.

Text::Table Update: I've written about resuming the maintenance of Text::Table in April, and it progressed nicely: the tests were converted to Test::More, a lot of the code was cleaned up, the build system was converted to Module::Build, and keywords and resource URLs were defined, and some bugs were solved (along with tests). I'm still looking into ways to clean up the code, and if anyone has an idea for a cool feature, then they should drop me a line (or provide a patch).

You cannot eat breakfast all day,
Nor is it the act of a sinner,
When breakfast is taken away,
To turn his attention to dinner;
And it's not in the range of belief,
To look upon him as a glutton,
Who, when he is tired of beef,
Determines to tackle the mutton.
Ah! But this I am willing to say,
If it will appease her sorrow,
I'll marry this lady today,
And I'll marry the other tomorrow!

-- William Schwenck Gilbert, "Trial By Jury"

It gives me great pleasure to announce Perl 5.12.4, the fifth stable release of Perl 5.12.

You can download Perl 5.12.4 from your favourite CPAN mirror or from:

http://search.cpan.org/dist/perl-5.12.4/

SHA1 digests for this release are:

68ff2f4a0901d1e4ea263f452001db0563d2edb3 perl-5.12.4.tar.bz2
b64a5d1fefe6db9c4144b4adba2c360afa9c29ea perl-5.12.4.tar.gz

This release contains bug fixes, build fixes and documentation updates. It should be fully backward compatible with Perl 5.12.3.