blogs.perl.org

A highlights/summary of recent activity and discussion on the #perl6 IRC channel on Freenode.net:

• nwc10: "jnthn: WTF did you just do? nqp head is 28% faster than 5 hours ago"
• nwc10 noted a 10-fold speed up for some NQP code: "nqp-jvm: 1.4725e+02 ... nqp-parrot: 2.0425e+03".
• pmichaud landed Rakudo commits to "Speed up repeated shifts of large lists/arrays by 70%+" noting that "More improvements are coming; this patch just gets a couple of the current big bottlenecks out of the way".

More in the full post...

Two days ago I was so excited! I had an idea how to make the Perl world a bit better, faster and simpler. Of course, I didn’t spread such exciting news until I checked and double-checked and benchmarked, until I’m absolutely sure I’ve found The Holy Grail.

Well, see the title. It hurts. All my benchmarks contained a terrible mistake. And those +20%, or, maybe even +100% speed boost PugiXML interface could provide doesn’t worth all the buzz I created.

I apologize.

I was recently interviews to the Russian online Perl magazine Pragmatic Perl. It was a pleasure and truly an honor. The last issue just came out and the interview is appearing there in Russian. If you speak Russian, go ahead and read it here.

If, like me, you do not speak Russian, following is the uncensored version in English.

So, imagine you're a CentOS user, and you want to install a CPAN module into the system. Let's say you want to install cpanm.

You get the root shell with sudo -s.
You enter: cpan App-cpanminus.
And then you enter: cpanm --help... and oops:

[root@localhost vagrant]# cpanm --help
bash: cpanm: command not found

WAT?

One of my next reviews is going to be web frameworks. I've posted my current plans on my new blog, where I'll be recording progress as I work through the review. I plan to implement the same application in each of the main frameworks I review, but would also be happy if others want to join in.

Even in the good old days of DOS, we already had color tables and extended ASCII characters to draw various border styles. So why limit ourselves with something like Text::ASCIITable? Introducing Text::ANSITable to make your text tables look pretty in terminals. See pictures for some examples:

Features:

Unfortunately, the idea contained fatal flaw. See the following post for explaantions.

Once upon a time I faced a huge pile of HTML files which I had to analyze. Say, there were about 1 000 000 of them. Say, 100 Gb of data.
Most of you would say “It’s not that much!”. And you are right. It’s not.

But then I’ve decided to estimate time required to process that pile of files. I quickly put XPaths of what I was needed together and got a prototype in Web::Scraper. And here I go: ~0.94s per file, i/o overhead not included. That occurred more than 11 days on my laptop. Phew!

There are only a few more days left to chip in to sponsoring work on Pinto. If you're still unconvinced or haven't thought about it yet, let me give my point of view on why you should spare a few minutes and a few bucks to sponsor Pinto.

Last week, Andy Lester (author of Land the Tech Job You Love) came to talk about tools to help programmers work more efficiently and the 2.0 release of his Ack search tool.

My experiment to crowd fund Jeff Thalhammer's Pinto development is going well. It's 87% of the way there. We need $503 to reach the campaign minimum. We have a week left to get that remaining 13% to get the campaign to "tilt", and I think we can get even more than that. Our secondary money goal is $5,000, all of which goes to Jeff to work on open source features of Pinto. I like $6425 (two perfect squares next to each other). That's 0b0001100100011001 (repeats the bit pattern) or 0x1919 (repeated, and the same prime next to itself).

On Monday Sean Quinlan became the 100th contributor. We have a week left to get 128 contributors. Part of the experiment is to get as many people involved as we can, at any level. I don't care how much you donate: a $1 donation is just as good as $100 when we are counting contributors.

Padre, the Perl IDE, is the work of a number of people with the goal of creating an IDE written in Perl itself.

Padre 0.98, according to the Release History page has finally been released 1 year and 1 week after 0.96.

This is a long time between releases. In part this can be put down to me as the Release Manager. As things go, we all have interests and busy times in our lives that can take us away from projects that we give up our free time to contribute to. For me, it's been a case of discovering photography. So instead of looking at code I'm looking at images I have taken.

This has meant, that try as I might, I never focused back on Padre and releasing Padre enough to get the new version out the door.

Well, tonight Padre 0.98 finally hits PAUSE.

For several years I've been using a shell script that runs once a day from a cron job, and automagically subscribes me to the RSS feeds that rt.cpan creates for my modules. That means that whenever I release a new module, within a day or two I'll be subscribed to its bug reports, and within another day or so I'll start getting bug reports automatically emailed to me.

At some point RT got upgraded and my script broke. When I became aware of it, I fixed it, and I also put it on github. I hope you find it useful.

To run it you will need to set the RTUSER and RTPASS environment variables and possibly edit the variables at the top of the script. I assume that you use rss2email for reading RSS feeds. Use of any other tool for RSS is a bug, but if you wish to be buggy I'm sure you can work around that.

"First we ask, what impact will our algorithm have on the parsing done in production compilers for existing programming languages? The answer is, practically none." -- Jay Earley's Ph.D thesis, p. 122.

[ This is cross posted from its home at the Ocean of Awareness blog.

In the above quote, the inventor of the Earley parsing algorithm poses a question. Is his algorithm fast enough for a production compiler? His answer is a stark "no".

This is the verdict on Earley's that you often hear repeated today, 45 years later. Earley's, it is said, has a too high a "constant factor". Verdicts tends to be repeated more often than examined. This particular verdict originates with the inventor himself. So perhaps it is not astonishing that many treat the dismissal of Earley's on grounds of speed to be as valid today as it was in 1968.

But in the past 45 years, computer technology has changed beyond recognition and researchers have made several significant improvements to Earley's. It is time to reopen this case.

I'm on IRC just about all the time (my handle is "thaljef"). But I thought it might be interesting to actually schedule a session and invite people to come in and ask questions about Pinto, suggest a feature, report a bug, or just say "Hi".

So there will be two one-hour jam sessions in the #pinto channel on irc.perl.org this Thursday, May 2. The first will at 14:00 and the second will be at 18:00 (all times GMT). If you haven't used IRC before, this is an excellent guide.

Hope to see you all then!

Welcome to Perl 5 Porters Monthly, a summary of the email traffic of the perl5-porters email list. This is the last monthly catch-up. I am planning to do weekly summaries for the week starting April 29, 2013. (But the road to hell is paved with yada yada yada...)

Topics from this month include:

• DAVEM TPF Grant Month 2013 report
• On eliminating external tools from the release process
• Blead on s390x
• archlib - (ed. RJBS asks, "Should we keep it or not?")
• Status of z/OS/EBCDIC
• NWCLARK TPF grant March report
• status on 5.18.0 (as of April 24, 2013)

cachegrind gives you information on the callstack and callcount, dependencies and efficiency. You can easily see hotspots in your code.

I use it to check the JIT and objmodel efficiency of potion, which is the vm for p2.

See my first post today Install kcachegrind on MACOSX with ports if you are on a Mac.

cachegrind

The first run with:

$ make bin/potion-s
$ valgrind --tool=callgrind -v --dump-every-bb=10000000 bin/potion-s example/binarytrees.pn
Ctrl-C

generates this sample

 $ open qcachegrind

Open one of the generated callgrind.out.pid.num files.

Especially for the weekend readers, here is my
interview with Michael Schwern. Enjoy and share!

Hi all,

Yesterday I released another IRC plugin for POE::Component::IRC: POE::Component::IRC::Plugin::WWW::Reddit::TIL

The plugin simply fetches a random title and link from the front page of Reddit's TodayILearned subreddit.

I used WWW::Shorten::Simple to return bitly links, and Mojo::JSON to decode reddit's API.

example:

curtis: !TIL
ircbot: curtis: TIL that the fighter squadron with the highest number of kills in the Battle of Britain during WWII were actually from Poland, and showed up two months after the battle had begun. http://bit.ly/ZN0qdB

links:

CPAN
Github

Hannover.pm is organising the 16th German Perl Workshop 2014 ( GPW 2014 ) in Hanover.

An official act.yapc.eu website is currently in the making and will be published in early June. Give us some time to understand and fully configure its back end.

The gpw2014 will take place from March 26th to 28th 2014 (Wednesday to Friday). The CeBIT will take place from March 11th to 15th, the Hannover Messe will take place from April 7th to 11th. We're smack-dab in the middle of those two big fairs, but hotel rooms will be affordable during that week.

I'll blog about the gpw2014 at least every month to keep you informed. But please also have a look at the official act website for major news.

If you like to chat you can join the IRC channel #gpw (#gpw2014 is for the organisers) on irc.perl.org.

German version: http://www.perl-community.de/bat/poard/thread/18295

Well, you don't want to install kcachegrind with port.

$ sudo port search cachegrind
kcachegrind @0.4.6 (devel)
    KCachegrind - Profiling Visualization

Because building KDE takes hours, and you wont need it other than for cachegrind. But there's a QT variant coming with kcachegrind, called qcachegrind. Maybe ports wants to use this variant. Or not, because kdelibs3 is listed as dependency.

$ sudo port info kcachegrind

kcachegrind @0.4.6, Revision 1 (devel) Variants: universal

Description: KCachegrind visualizes traces generated by profiling, including a tree map and a call graph visualization of the calls happening. It's designed to be fast for very large programs like KDE applications. Homepage: http://kcachegrind.sourceforge.net/

Library Dependencies: kdelibs3
Platforms: darwin
License: unknown
Maintainers: nomaintainer@macports.org