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acme (189)

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Leon Brocard (aka acme) is an orange-loving Perl eurohacker with many varied contributions to the Perl community, including the GraphViz module on the CPAN. YAPC::Europe was all his fault. He is still looking for a Perl Monger group he can start which begins with the letter 'D'.

Journal of acme (189)

Saturday November 21, 2009
03:56 AM

Perl 5.11.2

  The streets were pretty quiet, which was nice. They're always quiet here
  at that time: you have to be wearing a black jacket to be out on the
  streets between seven and nine in the evening, and not many people in the
  area have black jackets. It's just one of those things. I currently live
  in Colour Neighbourhood, which is for people who are heavily into colour.
  All the streets and buildings are set for instant colourmatch: as you
  walk down the road they change hue to offset whatever you're wearing.
  When the streets are busy it's kind of intense, and anyone prone to
  epileptic seizures isn't allowed to live in the Neighbourhood, however
  much they're into colour.
                 - Michael Marshall Smith, "Only Forward"

It gives me great pleasure to announce the release of Perl 5.11.2.

This is the third DEVELOPMENT release in the 5.11.x series leading to a stable release of Perl 5.12.0. You can find a list of high-profile changes in this release in the file "perl5112delta.pod" inside the distribution.

You can download the 5.11.2 release from:

The release's SHA1 signatures are:

   2988906609ab7eb00453615e420e47ec410e0077  perl-5.11.2.tar.gz

   0014442fdd0492444e1102e1a80089b6a4649682  perl-5.11.2.tar.bz2

We welcome your feedback on this release. If you discover issues with Perl 5.11.2, please use the 'perlbug' tool included in this distribution to report them. If Perl 5.11.2 works well for you, please use the 'perlthanks' tool included with this distribution to tell the all-volunteer development team how much you appreciate their work.

If you write software in Perl, it is particularly important that you test your software against development releases. While we strive to maintain source compatibility with prior stable versions of Perl wherever possible, it is always possible that a well-intentioned change can have unexpected consequences. If you spot a change in a development version which breaks your code, it's much more likely that we will be able to fix it before the next stable release. If you only test your code against stable releases of Perl, it may not be possible to undo a backwards-incompatible change which breaks your code.

Notable changes in this release:

  • It is now possible to overload the C operator
  • Extension modules can now cleanly hook into the Perl parser to define new kinds of keyword-headed expression and compound statement
  • The lowest layers of the lexer and parts of the pad system now have C APIs available to XS extensions
  • Use of C<:=> to mean an empty attribute list is now deprecated

Perl 5.11.2 represents approximately 3 weeks development since Perl 5.11.1 and contains 29,992 lines of changes across 458 files from 38 authors and committers:

Abhijit Menon-Sen, Abigail, Ben Morrow, Bo Borgerson, Brad Gilbert, Bram, Chris Williams, Craig A. Berry, Daniel Frederick Crisman, Dave Rolsky, David E. Wheeler, David Golden, Eric Brine, Father Chrysostomos, Frank Wiegand, Gerard Goossen, Gisle Aas, Graham Barr, Harmen, H.Merijn Brand, Jan Dubois, Jerry D. Hedden, Jesse Vincent, Karl Williamson, Kevin Ryde, Leon Brocard, Nicholas Clark, Paul Marquess, Philippe Bruhat, Rafael Garcia-Suarez, Sisyphus, Steffen Mueller, Steve Hay, Steve Peters, Vincent Pit, Yuval Kogman, Yves Orton, and Zefram.

Many of the changes included in this version originated in the CPAN modules included in Perl's core. We're grateful to the entire CPAN community for helping Perl to flourish.

Jesse Vincent or a delegate will release Perl 5.11.3 on December 20, 2009. Ricardo Signes will release Perl 5.11.4 on January 20, 2010. Steve Hay will release Perl 5.11.5 on February 20, 2010.

Regards, Léon

Thursday November 05, 2009
03:41 AM


OOPSLA 2009 happened a few weeks ago. OOPSLA stands for Object-Oriented Programming, Systems, Languages & Applications and I've always been quite interested in the conference. The proceedings of the conference aren't put online, but I've managed to find two interesting papers:

A Market-Based Approach to Software Evolution (PDF) tries to imagine an open market which is targetted around fixing bugs and improving software. It's quite interesting as it's quite similar to a proposal from Nicholas on spending other people's money. The authors point out many potential flaws.

The Commenting Practice of Open Source (PDF) analyses projects on Ohloh and tries to spot commenting trends. "We find that comment density is independent of team and project size", but they find that it varies from language to language. "Java has the highest mean of comment lines per source lines at.. one comment line for three source code lines" and "Perl has the lowest mean with.. one comment line for nine source code lines". They list as future work to find out why this might be the case.

Monday October 19, 2009
02:34 AM


A few weeks ago I was up in the hills about Geneva reminiscing with my sister about all the things we used to enjoy when we were smaller. When I was younger I used to really enjoy programming computer games, first on my 48K Spectrum and then later on in STOS BASIC and then 68000 assembly language on my Atari ST.

I haven't programmed a game in a very long time. However, I'm an avid gamer, playing games while travelling on my DS and at home on my Xbox 360. I almost enjoy reading Edge magazine more than I like playing games.

At YAPC::Europe in Lisbon, Domm pointed out that the Perl SDL project (which wraps the Simple DirectMedia Layer) was languishing and that we should all programs games in Perl.

A few months later I got around to playing with SDL and made a simple breakout clone which I styled after Batty on the Spectrum, but with gravity. It was fairly easy to program, but there was a lot to grasp. The Perl libraries are a mix between a Perl interface to SDL and a Perlish interface to SDL, with limited documentation, tests and examples.

Of course this is where I join the #sdl IRC channel on and start discussing with the other hackers (kthakore, garu, nothingmuch). We decide on a major redesign to split the project into two sections: the main code will just wrap SDL and then there will be another layer which makes it easier to use. I've started writing a bunch of XS on the redesign branch of the repository while trying to keep Bouncy (my game) still working. There is a bunch of work still to do but we've made a good start. This is what Bouncy looks like at the moment:

[YouTube video]

The physics are pretty fun and it runs pretty fast (1800 frames/second). I'm taking a little break as I'm off to Taipei...

Tuesday September 15, 2009
08:54 AM

Perl/iX for HP e3000 MPE

I'm trying to update various URLs in the Perl source code. Regarding the Perl/iX for HP e3000 MPE README.

It's very out of date now and most of the URLs are broken. I've contacted Mark Bixby, but he no longer has any involvement with the MPE/iX OS or that particular Perl port.

Does anyone run Perl on this platform? Does anyone build Perl on this platform? If so, please contact me and we'll try and update the details. Cheers!

Sunday August 16, 2009
08:46 AM

YAPC::Europe 2009

Two weeks ago I attended YAPC::Europe 2009 in Lisbon, Portgual. This wasn't the first YAPC in Portugal - in 2005 we went to Braga, a university town inland and it was a very well organised conference. It's no surprise the YAPC in Lisbon was also amazingly well organised, as it was the same organisers -  José Castro (cog), Alberto Simões (ambs) and Magda Joana Silva. Thank you so much José, Alberto, Magda and all the others involved - it was amazing.

The theme of the conference was "Corporate Perl" and this made a useful track in the vast schedule. It's amazing all the places Perl is used. Every talk I attended was great - the speakers knew their material and explained their content well. Some of the presentations are already online, see "Talk" in the schedule.

I liked the venue, three metro stops away from our hotel (also very walkable). The main room was huge and the three other tracks were just nearby, leaving a large space behind these for socialising with the just-over 300 attendees (and easy access to the sun). This was also where the terribly-important refreshments were, including oh-so-tasty pastéis de Nata.

The attendees' dinner was great. It was in a huge churrascaria (meat on swords!) by the river. It was also a good location for the Quizz Show, with 16 two-person teams fighting to be the geekiest. This was quite hard, as the questions varied from Portuguese history, Star Trek, Buffy and Perl internals ("How many levels of precedence does Perl 5.10.0 have?") to Unix history.

Community was very important at the conference - there are lots of seperate groups of Perl people clustered around the core, Perl modules, Perl projects or even cities and conferences are where you can mix, meet people in real life and start making crazy plans for the future. There are so many exciting things going on in Perl and I'm really looking forward to YAPC::Europe in Pisa in 2010!

Saturday August 15, 2009
07:18 AM


I always enjoy reading the papers of the SIGGRAPH conference. It's nice to see what new graphical techniques are coming. Here are my favourite picks from 2009:

The last one contains great quotes like "A stretched cow that is torn when two bars scissor together" and "These images from an animation show viscoelastic horses being dropped onto one another".

Thursday August 06, 2009
10:45 AM

Moose book

I love Moose. It's a postmodern object system for Perl 5. It's very powerful, saves me writing a lot of code and is very extensible. Dave Rolsky received a grant to write the Moose::Manual and it's a great introduction to Moose, how to use Moose and covers every part of it in detail. I don't really enjoying reading documentation on a screen, so I converted the manual from Pod to LaTeX so that the typography would be beautiful, fixed a few typos in the manual, designed a nice cover and you can now buy a copy for yourself. At the YAPC::Europe 2009 auction a copy of the book signed by Yuval Kogman and Larry Wall went for €120!

Wednesday July 15, 2009
03:21 AM Technical Meeting 30th July 2009

London Perl Mongers organises technical meetings every two months. The technical meetings are a chance to find out what has been going on in the Perl community, what techniques people are using and how Perl integrates with other software.

The next technical meeting will be on the 30th July from 7pm to 9pm (you may arrive from 6.30pm, sign in at the reception) and the theme  is “Corporate Perl”. You have to sign up to attend, see below. It will  be held at Gumtree's's offices near Richmond station. Many thanks to  Dave Cross, Gumtree and everyone involved for allowing us to use this wonderful venue.

Talks planned so far:

Dave Cross - Why do so many companies re-invent well-known CPAN
modules badly and end up writing far too much code?
Pedro Figueiredo - Perl in the cloud
Léon Brocard - Fewer cables

Our venue size is limited so you will have to sign up to attend this meeting.

See you there, Léon

Wednesday June 17, 2009
06:11 AM

Digital Britain

"The Digital Britain Report is the Government's strategic vision for ensuring that the UK is at the leading edge of the global digital economy. It is an example of industrial activism in a crucial growth sector.

The report contains actions and recommendations to ensure first rate digital and communications infrastructure to promote and protect talent and innovation in our creative industries, to modernize TV and radio frameworks, and support local news, and it introduces policies to maximize the social and economic benefits from digital technologies."

Got me watching BBC Parliament to see the announcement.

The Digital Britain was down after the announcement, leading to amusing comments on twitter.

It is available in PDF and MS Word formats

The report itself is 245 pages and the executive summary has 83 points, so here are my notes:

JPEG artifacts by every page number

Chapter 2: Being Digital

Chapter 2 is entitled "Being Digital", same title as a great book by Nicholas Negroponte published in 1995 where he tries to predict how the technologies will evolve. It's far more futuristic than this report, and the rate of change since 1995 is impressive.

P27 "Universal Broadband Service, at a speed of 2 Megabits per second, by no later than 2012"

P30 "The financial savings flowing from an ability to use comparison websites and online-only deals are worth an average of around £23 per month, per individual"

Economic benefits of digital inclusion by UK Online Centres (which disables right-clicks on links so I couldn't copy and paste, sigh)

P32 "It is already increasingly the case that those without access to the Internet suffer economic disadvantage"

P33 "Awareness of the Internet was widespread with only 3% of respondents saying they had never heard it"

P36 "Many of these personal computers could be put to secondary use". Computers are cheaper now, but affordability is key

P40 This figure is pointless and shows consultants were involved

P44-45 Shows how some television programmes can drive people online

Chapter 3a: A Competitive Digital Communications Infrastructure

No, I'm not quite sure why it's 3a either

P47 "The UK’s communications infrastructure is a vital enabler for the country’s society, economy, safety, security and well being"

P47-48 "In the case of broadband, realising the full value of the copper network cost tens of millions of pounds of investment; replacing it with a fibre network will take billions"

P48 "Our communications infrastructure finds itself in continuing and rapid technology evolution, in which the new
generation already looks unambitious by the time is fully rolled out. The Integrated Services Digital Network (ISDN) promised the ultimate international goal in 1984 of two telephone lines and a 16 Kbps data link to every home. The
Total Access Communications (TACS) mobile networks licensed in 1984 was viewed as the foundation of modern mobile communications, while the Videotex Services heralded as the last word in browsing for information. Not
only were none of them the last word, they were not even the last generation of “modern” networks but the generation before. All have been overtaken."

P48 "Next generation fixed fibre and cable networks offer not just conventional high-definition video entertainment and
games, but potentially more revolutionary benefits for our economy and society – telepresence, e-healthcare in the home and, for small and medium sized businesses, access to cloud computing (which substantially cuts hardware
and application costs and allows much more rapid product and service innovation)" seems rather unambitious and and odd place to hype cloud computing

P49 "The pattern over the past 25 years has been the arrival of more advanced fixed and mobile networks at roughly 8-10 years intervals and it should come as no surprise that the next cycle is coming up fast"

P50 "The areas of the country that are covered by the Virgin Media network already have local optical fibre rings that run through Virgin’s street cabinets serving typically 500-1000 homes. Broadband coaxial cables then connect to individual homes. Coaxial cable can support 4 Gbps bandwidth on a shared basis. Virgin Media will this year extend its 50Mbps offering...". Errr, 4Gbps/500 is 8Mbps, not 50Mbps

P50 "The other half of the country is served nearly exclusively by BT’s copper network as the only fixed network"

P50 "Without action being taken it is possible that entire metro areas could suffer data ‘brown outs’"

P52 "For those households who have it, broadband has become an essential utility as important as electricity, gas or voice telephony"

P53 "Universal availability of today’s network essentially requires incremental upgrades of existing infrastructure and the costs are therefore limited to the hundreds of millions of pounds. Delivering tomorrow’s network essentially involves installing a new network or networks, and the costs are in the billions... We will therefore take action on two fronts. First, we will ensure delivery of the Universal Service Commitment at 2Mbps, and second we will take action separately to address the issue of next generation broadband availability". This is the most important point that
people who have not read the report fail to grasp.

P54 "and wireless network engineered solutions (including satellite)" implies that 330k homes might be able to get 2Mbps but with the high latency of going via satellites in geostationary orbit

P54 "c.11%, or about 2.75m, homes cannot readily get a 2Mbps (or higher) broadband service today"

P56 image showing that Wales is a broadband deadzone

P59: "There are genuine negative consequences for a country still connected to the Internet at 14.4 Kbps today. In twenty years’ time, countries still connected to the Internet at 3.3Mbps (or the 256 Kbps that characterises the up-link speeds for many consumers today) will similarly be left behind" is a rare reference to up-link.

P59 "We welcome the substantial investment already taking place, and are confident that the UK’s competitive markets will provide the stimulus for further investment without any Government intervention, providing competitive coverage of superfast, next generation broadband for between half and two-thirds of the population"

P60-62 has interesting comparisons on how Finland (1Mbps by 2010, 100Mbps to 99% by 2016), Germany (1Mbps by 2010, 50Mbps to 75% by 2014), USA (US$7.2bn investment), Australia (FTTH or wireless by 2017) and
New Zealand (FTTH to 75% proposal) are investing in broadband.

P62-63 show the costs involved rolling out FTTC (£400 per connection) or FTTH (£2000 per connection)

P63-64 "There is no obvious means whereby the market, unaided, will serve the final third of the population. We therefore propose a Final Third Project to deliver at least 90% coverage of Next Generation broadband for homes and businesses by 2017"

P64 "The Government intends to propose a small general supplement on all fixed copper lines... from 2010 for a Next Generation Fund.... of 50p per month on fixed lines" is odd as it is the only price mentioned per month instead of per annum.

P65 "can be expected to raise £150m-£175m a year for the Fund" - it's not that much money.

P67 "there is at present no wholesale offering over Virgin Media’s network, a fact which BT and others have claimed is a factor limiting service innovation"

P69-70 "Today there is near universal coverage of GSM... But the extensive coverage we now take for granted with GSM has not yet happened with 3G networks... For these reasons, if we eventually move to a phasing out of GSM networks in favour of the next generation, we might face the end of universal mobile coverage in the UK. There are strong public policy arguments for wishing to preserve very extensive coverage" so it looks like GSM is here to stay

P79 "The Government... will, as part of its integrated package, convert existing 3G licences from time limited to indefinite" to help get to universal coverage for mobile broadband

P82 "one option is to make the provision of high speed broadband services part of the rail franchise requirements for train operators"

P82 "On the underground, the London Olympics in 2012, which will be the most digital Olympics in history, seems a particularly good reason for the Mobile Network Operators to work with the Mayor of London to provide and fund solutions to take the initiative to improve the broadband mobile access for mobile customers travelling by Tube"

Chapter 3b: Going Digital

P92 "digital offers a number of possibilities for radio to grow"

P93 "Radio services on MW will either upgrade to DAB or, if they are within the ultra-local tier, to FM. This will deliver an upgrade from FM to DAB and from MW to FM... by 2013" so by 2015 we will all need DAB receivers instead of FM

P94 "Digital radio is not now, nor should it be in the future, a single platform medium"

P95 "We are clear that at least for the foreseeable future DAB is the right technology for the UK" but they will hedge their bets with DAB+ or DMB-A

P97 "At a national level we will look to the BBC to begin an aggressive roll-out of its national multiplex to ensure its national digital radio services achieve coverage comparable to FM by the end of 2014..."

Chapter 4: Creative Industries in the Digital World

P109 "a significant proportion of consumers are choosing to access digital content unlawfully, principally via unlawful peer-to-peer file sharing" is a lot of unlawful

P111 "the Government will also provide for backstop powers for... Blocking (Site, IP, URL), Protocol blocking, Port blocking, Bandwidth capping (capping the speed of a subscriber’s Internet connection and/or capping the volume of data traffic which a subscriber can access); Bandwidth shaping (limiting the speed of a subscriber’s access to selected protocols/services and/or capping the volume of data to selected protocols/services); Content identification and filtering– or a combination of these measures.

P117 "introduce exceptional statutory maxima of £50,000 for all IP offences" to match penalties for online and physical copyright infringement

P119 "Industry participants argue that consumers should pay for a ‘right to copy’, reimbursing the copyright holder for the privilege of (a) retaining a recording of the material, and (b) being able to watch the material outside of the linear broadcast window" - but the Government will to add this as a tax on recording devices

Chapter 5: Public Service Content in Digital Britain

P140 "Free is very difficult for any paid-for business models to compete with"

P143 "the Government has therefore decided to consult openly on the idea of a Contained Contestable Element of the
Licence Fee used by or channelled through other organisations, primarily for news" might well lead to the end of the BBC's unique way of funding

Chapter 6: Research, Education and Skills for Digital Britain

P186 "It will soon not be possible to run a business effectively unless it is equipped with high-bandwidth access to the Internet. These are the roads of the 21st Century... the UK Government must seek next generation access that is scalable to 1Gb/s and beyond"

Chapter 7: Digital Security and Safety

P190 "It is not the Government’s policy to react to the challenge of the change the Internet presents by retreating to a position of protectionism or oppressive regulation"

P195 "The Government will carry out a major test in late 2009 of our ability to manage and recover from a major loss of network capacity"

Chapter 8: The Journey to Digital Government

P209 "Almost half of the UK population today have used the Internet in the last year to access information about Government or local council services or completed a Government form or process online, according to Ofcom research"

P212-213 "In addition to the Public Service Network we need to be able to add business applications to create a ‘G-Cloud’, using Cloud Computing... The G-Cloud delivery model would also help make other parts of the Government IT marketplace more cost-effective, flexible and competitive... and it would reduce the barriers to entry to the Government marketplace for application and other IT vendors, including SMEs, who would be able to provide services running on standardised, secure infrastructure without having to incur the costs of establishing and accrediting their own infrastructure"

P216 "Geographical data sets present some of the most valuable assets from which to develop online applications and services" but no changes for the Ordnance Survey

P220 "Concerns over privacy are only multiplied when arms of Government areinvolved in data gathering"

Chapter 9: Delivering Digital Britain

P229 "There is no room for complacency. The Government intends to do all it can to achieve the policy objectives we set out in this report, and urges all others to join it in the effort. The prize on offer is great. It will require a common effort to achieve it"

Tuesday June 16, 2009
08:02 AM


"Non relational databases" have seen quite a bit of interest recently. There was a NOSQL meeting in San Francisco last week and they have very kindly put some slides and videos up. I find it interesting but haven't got enough data yet...