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Philip Wadler: My friends wonder why any intelligent Scot would vote Yes

Planet Haskell - Sat, 01/18/2014 - 5:56am
David Donnison on Bella Caledonia presents a concise argument for independence that puts, far better than I could, my own views.
They asked me about many of the dilemmas we have been pondering in Scotland in the aftermath of our white paper – and most of them could not understand why any intelligent Scot would be voting for independence. It was an afternoon that compelled me to clarify my own thinking.
What matters most, I said, is not how an independent Scotland will fare. Independence will of course bring teething troubles of many kinds; but the Scots, if they choose to break away, will make their way in the world pretty successfully. What matters most, I said, is what you are doing in England; what kind of country you want to make of the UK; and whether we in Scotland want to be part of it.
The Scottish ‘political class’ assume that proposals for new policies should help to create a fairer and more equal society where there will be greater social justice. They assume that proposals for solving social problems should be prepared in active consultation with the kinds of people who experience these problems. Of course they do not always live up to these aspirations; but our political class assume that they will be generally accepted by Scottish governments, whoever wins our next elections. They are not contentious. None of that can be said of England.
I could give various examples of the impact of these divergent cultures, but one will have to do. When our first minister was taking questions at the press conference launching the independence white paper, a correspondent from the Daily Telegraph said (roughly speaking – I took no note): ‘Your plans for Scotland’s future are splendid. But in a country with high rates of unemployment and high proportions of pensioners, how can you pay for all this?’ To which Salmond replied: ‘That would indeed be difficult if nothing changes. But an independent Scotland will attract more young workers’. To which the Telegraph man – thinking he had a killer question – said: ‘You mean more immigrants?’. ‘Yes,’ said Salmond. ‘They make an important and creative contribution to our society and we need more of them.’ Could any serious English politician have said this? And if it had been said, would it have passed unnoticed, as it did in Scotland?
We shall all have to make our best guesses at England’s political trends when the referendum comes – eight months before the next Westminster election which may give us a few pointers. But if staying in the UK seems likely to mean living in a country that leaves the European Union (Miliband, if he wins the election, has not yet promised a referendum on that, but neither has he refused one); if it is to be a country that continues to impose increasingly punitive and humiliating sanctions on its poorest citizens who live on social security benefits (Labour spokespersons on this subject seem determined to show they will match the Tories’ brutalities); if the Human Rights Act is to be repealed (as our present home secretary promises); if the UK continues to have the most centralised government in the Western world (strangling local governments and killing off civic leadership); if ‘green’ policies are to have low priority; and if our armed forces are to remain mercenary outriders to American foreign policy; then I would rather get out, whatever the hazards of independence.
It’s a white paper, agreed by the main political parties, on the future plans and priorities, not of Scotland but of the rest of the UK, that I need. I guess I’ll have to place my bet without waiting for that.Spotted via @cstross and @andrewdrucker.
Categories: Offsite Blogs - Sat, 01/18/2014 - 5:08am
Categories: Offsite Blogs - Sat, 01/18/2014 - 5:08am
Categories: Offsite Blogs

language-puppet: The stm-firehose package

Planet Haskell - Sat, 01/18/2014 - 4:55am

I recently needed a specific kind of publish-subscribe primitive, where the publisher must not block, and that should not leak memory. It is published as the stm-firehose package.

It exposes an STM interface (built upon TBMQueue), but also higher level helpers. My use case is to be able to tap on a message stream at will, and observe some of the messages as they flow through the infrastructure. The clients will join and leave at any time, possibly from a low bandwidth connection. This means that they might not be able to cope with the traffic, but this should not adversely affect the publisher or other clients.

To cover common use cases, two helpers are exposed in the Data.Conduit.Network.Firehose module :

  • firehoseApp: creates a WAI application that lets firehose clients connect through a web interface.
  • firehoseConduit: spawns a WARP server waiting for clients to connect, and returns a Conduit that will make all messages traversing it available to clients.

Finally, a specialized version of firehoseConduit, called firehose, has been included in the Data.Conduit.Firehose module of the hslogstash package, in the name of fireHose. This version is specialized for querying logstash messages, and yes, the naming of the function and module could have been better.

It might have been a better idea to just create a TCP server for the helper functions, instead of a more complex HTTP server, but this would have required writing a custom protocol for handling the client “preferences” in the kind of messages they would like to see. As it stands, the user of the helper functions can pass a filtering function that can adjust its behavior based on the client HTTP request. This is exploited in the logstash-specific helper function by letting the client specify the list of message types he would like to see in the URL.

As a side note, there have been quite a few improvement and bug fixes in language-puppet since last time I blogged about it. There still are a few issues to close before releasing a new version.

Categories: Offsite Blogs

Open researcher position at Create-Net Italy

haskell-cafe - Sat, 01/18/2014 - 4:03am
Dear Haskell-cafe, CREATE-NET, a research center located in Trento, Italy, is hiring one researcher on distributed system management. The responsibility of the candidate will be to contribute to the research topic of Energy Efficiency in the Cloud with particular focus on making cloud-running applications energy-aware. The techniques used will include Constraint Programming and Functional Programming to some extent. We offer competitive compensation and a stimulating work environment in the research and innovation sector. The scenic landscape of Italian Alps doesn't hurt either. If you are interested, please submit your application to careers< at > (with me in copy). Details on the open position and ideal profile may be found on Don't hesitate to contact me for more details! Cheers, Corentin Dupont CREATE-NET _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe< at > http://
Categories: Offsite Discussion - Sat, 01/18/2014 - 1:57am
Categories: Offsite Blogs

POPL 2014 proceedings available freely for all

Lambda the Ultimate - Sat, 01/18/2014 - 1:18am

The proceedings can be downloaded from the POPL webpage.

I find this extremely exciting (not only because I didn't get funds to attend POPL this year). To my knowledge, this is the first time that this is done in POPL/ICFP/PLDI; electronic proceedings were previously only delivered to attendees, with an explicit request not to share them.

I am not sure what is the reasoning that make which people decide to do it this year, or not to do it before. I hope that the proceedings will remain available after the conference (next week), and that this idea will be adopted for the years to come.

Categories: Offsite Discussion

Speeding Through Haskell - Sat, 01/18/2014 - 12:03am
Categories: Offsite Blogs

ANNOUNCE: Diagrams 1.0

haskell-cafe - Fri, 01/17/2014 - 11:57pm
The diagrams team is very pleased to announce the 1.0 release of diagrams [1], a framework and embedded domain-specific language for declarative drawing in Haskell. Check out the gallery [2] for some examples of what it can do. Diagrams can be used for a wide range of purposes, from data visualization [3] to illustration [4] to art [5], and diagrams code can be seamlessly embedded in blog posts [6], LaTeX documents [7], and Haddock documentation [8], making it easy to incorporate diagrams into your documents with minimal extra work. [1] [2] [3] [4] [5] [6] [7]
Categories: Offsite Discussion

Automatic differentiation and dimension types

haskell-cafe - Fri, 01/17/2014 - 11:23pm
Has anyone explored the intersection between automatic differentiation and dimension types (like those in the dimensional package or along the lines of any of the approaches discussed at It's tricky because for ordinary automatic differentiation the types are all the same, but when dimensions get involved that isn't the case, you have to keep dividing by the dimension of the infinitesimal. -Doug McClean _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe< at >
Categories: Offsite Discussion - Fri, 01/17/2014 - 10:14pm
Categories: Offsite Blogs

PureScript v0.3 Release Notes

Haskell on Reddit - Fri, 01/17/2014 - 8:46pm
Categories: Incoming News

off-topic question: how well do you think linguistic relativity applies to PLs and programming?

haskell-cafe - Fri, 01/17/2014 - 8:14pm
Hi all, I recently got myself thinking about programming languages and their effects on programmers. I already knew that concept of "linguistic relativity" ( ) and I was thinking that this may be relevant with programming too, although I don't have any concrete evidence. I was wondering if anyone else also find that idea of programming language's effect of the programmer interesting. Do we have any research on that kinds of things? Thanks,
Categories: Offsite Discussion

ANN: pooled-io

haskell-cafe - Fri, 01/17/2014 - 6:07pm
I uploaded the package pooled-io to Hackage: It is intended to perform parallelism in the IO monad. I needed it for computations that must write intermediate data to disk. The main task of the package is to make sure that no more than a maximum number of actions is run in parallel. There are three modules: For actions without monadic results, for actions with monadic results and for actions that depend on each others results.
Categories: Offsite Discussion

Brent Yorgey: Diagrams 1.0

Planet Haskell - Fri, 01/17/2014 - 3:57pm

The diagrams team is very pleased to announce the 1.0 release of diagrams, a framework and embedded domain-specific language for declarative drawing in Haskell. Check out the gallery for some examples of what it can do. Diagrams can be used for a wide range of purposes, from data visualization to illustration to art, and diagrams code can be seamlessly embedded in blog posts, LaTeX documents, and Haddock documentation, making it easy to incorporate diagrams into your documents with minimal extra work.

        What’s new

Brent recently gave a talk at the New York Haskell Users’ Group presenting the new release. You can find videos of the talk on vimeo: part 1 presents a basic introduction to the library, and part 2 talks about mathematical abstraction and DSL design. The slides are also available.

This release includes a number of significant new features and improvements. Highlights include:

  • Support for drawing arrows between given points or between diagrams, with many options for customization (tutorial, documentation, API).

  • A new framework for creating custom command-line-driven executables for diagram generation (tutorial, API).

  • Offsets of trails and paths, i.e. compute the trail or path lying a constant distance from the given one (documentation, API).

  • A new API, based on Metafont, for constructing cubic splines with control over things like tangents and “tension” (tutorial, API).

  • Tangent and normal vectors of segments and trails (API).

  • Alignment can now be done by trace in addition to envelope (API).

  • The lens package is now used consistently for record fields throughout the library (documentation).

  • Across-the-board improvements in performance and size of generated files.

See the release notes for full details, and the migration guide for help porting your diagrams 0.7 code to work with diagrams 1.0.

Try it out

For the truly impatient:

cabal install diagrams

Diagrams is supported under GHC 7.4 and 7.6.

To get started, read the quick start tutorial, which will introduce you to the fundamentals of the framework and provide links for further reading.

For those who are less impatient and want to really dig in and use the power features, read the extensive user manual. There is also a growing collection of tutorials on specific topics.

Get involved

Diagrams has a friendly and growing community of users and developers. To connect with the community, subscribe to the project mailing list, and/or come hang out in the #diagrams IRC channel on for help and discussion. Development continues stronger than ever, and there are a wide range of projects available for new contributors of all levels of Haskell skill. Make some diagrams. Fix some bugs. Submit your cool examples for inclusion in the gallery or your cool code for inclusion in the diagrams-contrib package.

Happy diagramming!

Brought to you by the diagrams team:

  • Daniel Bergey
  • Jeff Rosenbluth
  • Ryan Yates
  • Brent Yorgey

with contributions from:

  • Jan Bracker
  • Conal Elliott
  • Daniil Frumin
  • Sam Griffin
  • Niklas Haas
  • Peter Hall
  • Claude Heiland-Allen
  • Deepak Jois
  • John Lato
  • Felipe Lessa
  • Chris Mears
  • Ian Ross
  • Carlos Scheidegger
  • Vilhelm Sjöberg
  • Michael Sloan
  • Jim Snavely
  • Luite Stegeman
  • Kanchalai Suveepattananont
  • Michael Thompson
  • Scott Walck

Categories: Offsite Blogs

Collecting resources about Haskell - [here](

Haskell on Reddit - Fri, 01/17/2014 - 9:48am

Recently came across with Silk (which use Haskell for back-end stuff) and start using it for collect the Haskell materials. FP learning resources

Now there are following categories

  • Books on Haskell 14
  • Haskell video materials 9
  • Courses on Haskell 7
  • P. Wadler articles on monad 3

Any suggestion regarding new categories or resource highly appreciated.

We can make this site a great place to collect Haskell resources.

if anyone want to contribute I will glad to grant admin access to this site. thanks

submitted by ArthurVard
[link] [5 comments]
Categories: Incoming News