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Final Call For Papers: Implementation and Application of Functional Languages 2012, Oxford, UK
by Tom Harper 17 Jul '12

17 Jul '12

The deadline for pre-symposium drafts, 30 July, is approaching! IFL has a post-symposium review process, so it is a great chance to submit a draft or extended abstract and get feedback before the review process. ------------------------------------------------------------------------------- CALL FOR PAPERS 24th Symposium on Implementation and Application of Functional Languages (IFL 2012) University of Oxford, UK, August 30-September 1, 2012 http://www.cs.ox.ac.uk/conferences/IFL2012/ This year IFL will be hosted by the University of Oxford, within the idyllic setting of the dreaming spires and picturesque colleges, which have been the home to academic endeavour and research for over nine centuries. The symposium will be held between 30 August and 1 September, 2012. Scope ----- The goal of the IFL symposia is to bring together researchers actively engaged in the implementation and application of functional and function-based programming languages. IFL 2012 will be a venue for researchers to present and discuss new ideas and concepts, work in progress, and publication-ripe results related to the implementation and application of functional languages and function-based programming. Following the IFL tradition, IFL 2012 will use a post-symposium review process to produce formal proceedings which will be published by Springer Verlag in the Lecture Notes in Computer Science series. All participants in IFL 2012 are invited to submit either a draft paper or an extended abstract describing work to be presented at the symposium. Work submitted to IFL must not be submitted simultaneously to other venues; submissions must adhere to ACM SIGPLAN's republication policy: http://www.sigplan.org/republicationpolicy.htm. The submissions will be screened by the program committee chair to make sure they are within the scope of IFL, and will appear in the draft proceedings distributed at the symposium. Submissions appearing in the draft proceedings are not peer-reviewed publications. After the symposium, authors will be given the opportunity to incorporate the feedback from discussions at the symposium and will be invited to submit a revised full article for the formal review process. From the revised submissions, the program committee will select papers for the formal proceedings considering their correctness, novelty, originality, relevance, significance, and clarity. Topics ------ IFL welcomes submissions describing practical and theoretical work as well as submissions describing applications and tools. If you are not sure that your work is appropriate for IFL 2012, please contact the PC chair at ralf.hinze(a)cs.ox.ac.uk. Topics of interest include, but are not limited to: language concepts type checking contracts compilation techniques staged compilation run-time function specialization run-time code generation partial evaluation (abstract) interpretation generic programming automatic program generation array processing concurrent/parallel programming concurrent/parallel program execution functional programming and embedded systems functional programming and web applications functional programming and security novel memory management techniques run-time profiling and performance measurements debugging and tracing virtual/abstract machine architectures validation and verification of functional programs tools and programming techniques (industrial) applications of functional programming Submission details ------------------ Presentation submission deadline: July 30th, 2012 Notification of acceptance: August 1st, 2012 Early registration deadline: August 10th, 2012 IFL 2012 Symposium: August 30-September 1, 2012 Submission for (post) review process: November 30th, 2012 Notification Accept/Reject: February 4th, 2013 Camera ready version: March 18th, 2013 Prospective authors are encouraged to submit papers or extended abstracts to be published in the draft proceedings and to present them at the symposium. All contributions must be written in English, conform to the Springer-Verlag LNCS series format and not exceed 16 pages. The draft proceedings will appear as a technical report of the Department of Computer Science of the University of Oxford. (We are more liberal with the draft proceedings, where longer papers or SIGPLAN 2 column 12 page papers are acceptable. For other formats please contact the chair at ralf.hinze(a)cs.ox.ac.uk. For consideration for the final proceedings, only the 16 page LNCS format will be accepted.) Papers are to be submitted via the conference's EasyChair submission page: https://www.easychair.org/conferences/?conf=ifl2012 Peter Landin Prize ------------------ The Peter Landin Prize is awarded to the best paper presented at the symposium every year. The honoured article is selected by the program committee based on the submissions received for the formal review process. The prize carries a cash award equivalent to 150 Euros. Programme committee ------------------- Edwin Brady, University of St. Andrews, UK Andrew Butterfield, University of Dublin, Ireland Matthew Flatt, University of Utah, US Andy Gill, University of Kansas, US Stephan Herhut, Intel Labs, Santa Clara, US Ralf Hinze (Chair), University of Oxford, UK Zhenjiang Hu, National Institute of Informatics, Japan Patrik Jansson, Chalmers University of Technology, Sweden Mauro Jaskelioff, Universidad Nacional de Rosario, Argentina Gabriele Keller, University of New South Wales, Australia Simon Marlow, Microsoft Research, UK Pablo Nogueira, Technical University of Madrid, Spain Bruno Oliveira, Seoul National University, Korea José Nuno Oliveira, University of Minho, Portugal Rinus Plasmeijer, Radboud University Nijmegen, Netherlands Tom Schrijvers, Ghent University, Belgium Tim Sheard, Portland State University, US Wouter Swierstra, University of Utrecht, Netherlands Peter Thiemann, University of Freiburg, Germany Simon Thompson, University of Kent, UK Steve Zdancewic, University of Pennsylvania, US

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A riddle...
by Andreas Abel 16 Jul '12

16 Jul '12

Today a student came to me with a piece of code that worked it executed by itself, but produced different result in the context of his larger problem. We cut down the example to the following: > import Graphics.UI.Gtk > > -- should produce [(26471,0,65535),... > rgbliste = > (map (\ i -> > let rb = 5 * (mod (mod 181935629 (4534+i)) 100)-250+128 in > let gb = 5 * (mod (mod 128872693 (5148+i)) 100)-250+128 in > let bb = 5 * (mod (mod 140302469 (7578+i)) 100)-250+128 in > let r = min 255 $ max 0 rb in > let g = min 255 $ max 0 gb in > let b = min 255 $ max 0 bb in > (r*257,g*257,b*257)) [0..]) > > --farbliste = map (\ (r,g,b) -> Color r g b) rgbliste > > main :: IO () > main = do > print $ head rgbliste If you run it, it prints (26471,0,65535). If you uncomment the def. of farbliste, it prints (44461,65535,65535). I was surprised. What is going on? Cheers, Andreas -- Andreas Abel <>< Du bist der geliebte Mensch. Theoretical Computer Science, University of Munich Oettingenstr. 67, D-80538 Munich, GERMANY andreas.abel(a)ifi.lmu.de http://www2.tcs.ifi.lmu.de/~abel/

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ANNOUNCE: Pup-Events-1.0
by Dan 15 Jul '12

15 Jul '12

Hello! This is my first release on Hackage and haskell@. So without further ado, here we go! Pup-Events is a collection of modules I initially created to help aid me in game development. It's main purpose is to facilitate the sending, receiving, creation, and handling of events in networked, third-party programs. It consists of the following packages: * Pup-Events-Client: The client facing code, contains the PupEventsClient module. You spawn a bunch of these and connect them to Pup-Events-Server * Pup-Events-Server: The server code, you'd only have one of these. This contains the PupEventsServer module. * Pup-Events-PQueue: A small priority queue implementation I made. The Client and Server use this when sending events. Contains the PupEventsPQueue module. In addition there's also a package "Pup-Events-Demo" which contains a small demo application I wrote in OpenGL to show off the framework. It's designed to be an example of what you can do with Pup-Events. You can pull all of the Pup-Events modules (not including the demo) by installing Pup-Events, which is a meta-package to pull in the Client, Server, and PQueue modules. Hopefully everyone enjoys it! I've certainly found it useful. Daniel Wilson -- ~~ Whatever happens, the sun's still gonna come up tomorrow ~~

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Re: [Haskell] Spam on the Haskell wiki
by Ashley Yakeley 15 Jul '12

15 Jul '12

I have verified that a verified email address is required to edit (by creating an account). -- Ashley On Sat, 2012-07-14 at 20:52 -0700, Mark Lentczner wrote: > We probably need more than just recaptcha (don't use anything else - > they are breakable) - there are real-time forum spammer lists one > needs to consult, and other measures. It may seem draconian, but for > other communities I run on the web, we've given up and have to resort > to manual review of every account request. > > > > - Mark > > > > On Sat, Jul 14, 2012 at 6:05 PM, Don Stewart <dons00(a)gmail.com> wrote: > > More admins on the wiki is good, esp. those with experience to > implement anti-spam measures. > > > > Ashley is around , but as usual, we need more help. > > > > On Saturday, July 14, 2012, Gwern Branwen wrote: > > I recently moved, and when I returned to the Internet > a few days > later, I was greeted with several hundred spam pages > in Recent > Changes. The torrent of spam has not let up, and I > estimate that I > have blocked 3-500 accounts and deleted as many pages. > (I blocked > another 5 or so while composing this email.) Certainly > the deletion > and block logs are long enough: > > - > http://www.haskell.org/haskellwiki/index.php?title=Special%3ALog&type=delet… > - > http://www.haskell.org/haskellwiki/index.php?title=Special:Ipblocklist&limi… > > I have asked Ashley Yakeley to turn on additional > anti-spam measures, > but he has not been active on the wiki since January > (http://www.haskell.org/haskellwiki/Special:Contributions/Ashley_Y > http://www.haskell.org/haskellwiki/index.php?title=Special:Log&user=Ashley_Y) > and has not replied to my talk messages or > accompanying emails. > > I had to do this single-handedly as there are no other > administrators. > This took up a good chunk of today and yesterday, and > the spam is > continuing. I cannot handle it much longer: it's > incredibly tedious > and using up far more time than I have to give it. > Measures need to be > taken: > > 1. Email confirmation needs to be checked that Ashley > did in fact > enable it. I suspect he did not, since I also > administrate the > LessWrong wiki - which I know for certain has email > confirmation is > enabled - is being attacked by the same spammers > (similar or identical > templates & spam) but at a much reduced scale. > 2. Additional administrators must be created. I > suggest: > > - dons > - Magnus Therning > - Neil Mitchell > - byorgey > - Henk-Jan van Tuyl > > I am sure there are others who can be trusted. > 3. Additional bureaucrats should be created. I suggest > myself. > 4. ReCAPTCHA enabled for 'edits adding new, > unrecognized external > links' - which is all of the spam. Further reading: > http://www.mediawiki.org/wiki/Manual:Combating_spam & > http://www.mediawiki.org/wiki/Anti-spam_features > 5. if Ashley is inactive, his account may be a > security risk. The > English Wikipedia now removes administrator bits after > a year of > inactivity; we should consider a similar policy. > > None of these can be taken by myself, as I am neither > a sysadmin on > Haskell.org nor a bureaucrat on the wiki. > > If none of these steps are taken and spam continues to > remain a > problem in 2 months (15 September 2012), I will cease > patrolling > Recent Changes. I no longer have the time or patience. > > -- > gwern > http://www.gwern.net > > > > _______________________________________________ > Haskell mailing list > Haskell(a)haskell.org > http://www.haskell.org/mailman/listinfo/haskell > > >

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GHC users on PowerPC and *BSD/Darwin?
by Erik de Castro Lopo 12 Jul '12

12 Jul '12

Hi all, Users of GHC on PowerPC would probably be aware of this bug: http://hackage.haskell.org/trac/ghc/ticket/2972 which causes GHCi to segfault as soon as it was started. Ben M. Collins has come up with a fix for this I am preparing it for submission to the GHC git tree. I have have tested it on linux-powerpc, but would also like to test it on *BSD/Darwin. Anybody out there interested? You will need: * A PowerPC machine running *BSD or Darwin. * A working GHC compiler. If you're interested email me at erikd AT mega-nerd dot com. Cheers, Erik -- ---------------------------------------------------------------------- Erik de Castro Lopo http://www.mega-nerd.com/

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Haskell Weekly News: Issue 235
by Daniel Santa Cruz 12 Jul '12

12 Jul '12

Welcome to issue 235 of the HWN, an issue covering crowd-sourced bits of information about Haskell from around the web. This issue covers the week of July 1 to 7, 2012. Quotes of the Week * Kukkua: They say there are two things, once mastered, you will harness boundless strength from the cosmos itself, continuations and monads. * startling: saying "monad" within earshot of a muggle is pretty funny * maybefbi: Haskell is forcing me to think a lot * Wadler says: So, the essence of XML is this: the problem it solves is not hard, and it does not solve the problem well. Top Reddit Stories * This is what my first attempt at writing code in Haskell went like Domain: self.haskell, Score: 82, Comments: 32 On Reddit: [1] http://goo.gl/uq3Tt Original: [2] http://goo.gl/uq3Tt * The Architecture of Open Source Applications: The Glasgow Haskell Compiler Domain: aosabook.org, Score: 59, Comments: 5 On Reddit: [3] http://goo.gl/5v906 Original: [4] http://goo.gl/yYqUJ * Slides for 7 lectures on Parallel and Concurrent Haskell (including GPU programming with Accelerate) Domain: community.haskell.org, Score: 51, Comments: 10 On Reddit: [5] http://goo.gl/pmGsr Original: [6] http://goo.gl/wumiT * How pythoners view Haskell compared with Python Domain: wiki.python.org, Score: 40, Comments: 70 On Reddit: [7] http://goo.gl/Xe3AF Original: [8] http://goo.gl/ydpyj * How I made the switch to functional programming. Domain: self.haskell, Score: 38, Comments: 14 On Reddit: [9] http://goo.gl/m6IXs Original: [10] http://goo.gl/m6IXs * Why Functional Matters: Your white board will never be the same Domain: blog.jessitron.com, Score: 35, Comments: 5 On Reddit: [11] http://goo.gl/b71zi Original: [12] http://goo.gl/SkJaA * Building a better AES package Domain: tab.snarc.org, Score: 33, Comments: 19 On Reddit: [13] http://goo.gl/A0hwE Original: [14] http://goo.gl/0p9PE * FP Complete is hiring Haskell programmers Domain: haskellers.com, Score: 32, Comments: 4 On Reddit: [15] http://goo.gl/L8Xuh Original: [16] http://goo.gl/6AxT7 * Parallel and Concurrent Programming in Haskell (Lab exercises by Simon Marlow) Domain: community.haskell.org, Score: 31, Comments: On Reddit: [17] http://goo.gl/cjBJ0 Original: [18] http://goo.gl/olFva * pipes 2.1 released with prettier Frame, using indexed and restricted monads Domain: haskellforall.com, Score: 30, Comments: 31 On Reddit: [19] http://goo.gl/Trajz Original: [20] http://goo.gl/vqluc * conduit 0.5.0 released, now with extensive tutorial Domain: hackage.haskell.org, Score: 27, Comments: 2 On Reddit: [21] http://goo.gl/s5Wmh Original: [22] http://goo.gl/RUrpw * A (experimental) treat for Emacs interactive-mode users Domain: youtube.com, Score: 26, Comments: 2 On Reddit: [23] http://goo.gl/13wD9 Original: [24] http://goo.gl/C54V5 * Exploring CPU design using Haskell - Introduction to the architecture Domain: random.axman6.com, Score: 25, Comments: 17 On Reddit: [25] http://goo.gl/f1v2M Original: [26] http://goo.gl/xvSUF * Haskell is dead! (pun intended, not a flame :D) Domain: i.imgur.com, Score: 22, Comments: 37 On Reddit: [27] http://goo.gl/jPRu9 Original: [28] http://goo.gl/2DclX * Announcing lens-family-core, lens-family, and lens-family-th Domain: self.haskell, Score: 22, Comments: 8 On Reddit: [29] http://goo.gl/Axyxs Original: [30] http://goo.gl/Axyxs * Happstack Irregular News Issue #2 Domain: happstack.com, Score: 21, Comments: 3 On Reddit: [31] http://goo.gl/n7a0Z Original: [32] http://goo.gl/kU7OV * "Tying the Knot" using the RWS Monad Domain: mergeconflict.com, Score: 21, Comments: 16 On Reddit: [33] http://goo.gl/FavKj Original: [34] http://goo.gl/TESiO * LiveScript: a more functional JavaScript Domain: gkz.github.com, Score: 18, Comments: 9 On Reddit: [35] http://goo.gl/NQecG Original: [36] http://goo.gl/1hsTo Top StackOverflow Questions * Functional design patterns votes: 36, answers: 5 Read on SO: [37] http://goo.gl/hjzwm * Using return vs. not using return in the list monad votes: 22, answers: 6 Read on SO: [38] http://goo.gl/zkQH1 * Compute as much of a list as possible in a fixed time votes: 19, answers: 3 Read on SO: [39] http://goo.gl/BpBFe * Why is `logBase 10 x` slower than `log x / log 10`, even when specialized? votes: 16, answers: 2 Read on SO: [40] http://goo.gl/4rkTi * How has Haskell changed? votes: 16, answers: 2 Read on SO: [41] http://goo.gl/Rkz41 * What are the similarities and differences among Haskell indentation modes for Emacs? votes: 16, answers: 0 Read on SO: [42] http://goo.gl/xHn7L * Arrow equivalent of mapM? votes: 9, answers: 1 Read on SO: [43] http://goo.gl/XlQWR * Can I pass a pattern into a function? votes: 9, answers: 2 Read on SO: [44] http://goo.gl/J6N3w * Referential transparency and mmap in Haskell votes: 8, answers: 1 Read on SO: [45] http://goo.gl/iJGp5 * Is EC2 Ubuntu 12.04 different, if compiling Haskell locally? votes: 7, answers: 1 Read on SO: [46] http://goo.gl/Qivdq Until next time, Daniel Santa Cruz References 1. http://www.reddit.com/r/haskell/comments/w3k4v/this_is_what_my_first_attemp… 2. http://www.reddit.com/r/haskell/comments/w3k4v/this_is_what_my_first_attemp… 3. http://www.aosabook.org/en/ghc.html 4. http://www.reddit.com/r/haskell/comments/w2skx/the_architecture_of_open_sou… 5. http://community.haskell.org/~simonmar/slides/cadarache2012/ 6. http://www.reddit.com/r/haskell/comments/vyzj8/slides_for_7_lectures_on_par… 7. http://wiki.python.org/moin/PythonVsHaskell 8. http://www.reddit.com/r/haskell/comments/w2jiv/how_pythoners_view_haskell_c… 9. http://www.reddit.com/r/haskell/comments/w77xy/how_i_made_the_switch_to_fun… 10. http://www.reddit.com/r/haskell/comments/w77xy/how_i_made_the_switch_to_fun… 11. http://blog.jessitron.com/2012/06/why-functional-matters-your-white-board.h… 12. http://www.reddit.com/r/haskell/comments/w1453/why_functional_matters_your_… 13. http://tab.snarc.org/posts/haskell/2012-07-07-building-a-better-haskell-aes… 14. http://www.reddit.com/r/haskell/comments/w6btf/building_a_better_aes_packag… 15. http://www.haskellers.com/jobs/14 16. http://www.reddit.com/r/haskell/comments/w4xyc/fp_complete_is_hiring_haskel… 17. http://community.haskell.org/~simonmar/lab-exercises-cadarache.pdf 18. http://www.reddit.com/r/haskell/comments/vzpfy/parallel_and_concurrent_prog… 19. http://www.haskellforall.com/2012/07/pipes-21-and-index-core-10-indexed.html 20. http://www.reddit.com/r/haskell/comments/vx1dt/pipes_21_released_with_prett… 21. http://hackage.haskell.org/packages/archive/conduit/0.5.0/doc/html/Data-Con… 22. http://www.reddit.com/r/haskell/comments/vwge4/conduit_050_released_now_wit… 23. http://www.youtube.com/watch?v=pu9AGSOySlE 24. http://www.reddit.com/r/haskell/comments/w1k7s/a_experimental_treat_for_ema… 25. http://random.axman6.com/blog/?p=327 26. http://www.reddit.com/r/haskell/comments/w4aan/exploring_cpu_design_using_h… 27. http://i.imgur.com/zzQrx.png 28. http://www.reddit.com/r/haskell/comments/vvkkm/haskell_is_dead_pun_intended… 29. http://www.reddit.com/r/haskell/comments/w5ine/announcing_lensfamilycore_le… 30. http://www.reddit.com/r/haskell/comments/w5ine/announcing_lensfamilycore_le… 31. http://www.happstack.com/C/ViewPage/12 32. http://www.reddit.com/r/haskell/comments/vxi3c/happstack_irregular_news_iss… 33. http://mergeconflict.com/archives/57 34. http://www.reddit.com/r/haskell/comments/w0haf/tying_the_knot_using_the_rws… 35. http://gkz.github.com/LiveScript/ 36. http://www.reddit.com/r/haskell/comments/w39a3/livescript_a_more_functional… 37. http://stackoverflow.com/questions/11339637/functional-design-patterns 38. http://stackoverflow.com/questions/11323300/using-return-vs-not-using-retur… 39. http://stackoverflow.com/questions/11320180/compute-as-much-of-a-list-as-po… 40. http://stackoverflow.com/questions/11290929/why-is-logbase-10-x-slower-than… 41. http://stackoverflow.com/questions/11296157/how-has-haskell-changed 42. http://stackoverflow.com/questions/11365815/what-are-the-similarities-and-d… 43. http://stackoverflow.com/questions/11303642/arrow-equivalent-of-mapm 44. http://stackoverflow.com/questions/11336687/can-i-pass-a-pattern-into-a-fun… 45. http://stackoverflow.com/questions/11283975/referential-transparency-and-mm… 46. http://stackoverflow.com/questions/11278733/is-ec2-ubuntu-12-04-different-i…

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Haskell Implementors' Workshop talk proposals due in one week!
by Johan Tibell 09 Jul '12

09 Jul '12

Call for Talks ACM SIGPLAN Haskell Implementors' Workshop http://haskell.org/haskellwiki/HaskellImplementorsWorkshop/2012 Copenhagen, Denmark, September 14th, 2012 The workshop will be held in conjunction with ICFP 2012 http://www.icfpconference.org/icfp2012/ Important dates Proposal Deadline: 10th July 2012 Notification: 27th July 2012 Workshop: 14th September 2012 The Haskell Implementors' Workshop is to be held alongside ICFP 2012 this year in Copenhagen, Denmark. There will be no proceedings; it is an informal gathering of people involved in the design and development of Haskell implementations, tools, libraries, and supporting infrastructure. This relatively new workshop reflects the growth of the user community: there is a clear need for a well-supported tool chain for the development, distribution, deployment, and configuration of Haskell software. The aim is for this workshop to give the people involved with building the infrastructure behind this ecosystem an opportunity to bat around ideas, share experiences, and ask for feedback from fellow experts. We intend the workshop to have an informal and interactive feel, with a flexible timetable and plenty of room for ad-hoc discussion, demos, and impromptu short talks. Scope and target audience ------------------------- It is important to distinguish the Haskell Implementors' Workshop from the Haskell Symposium which is also co-located with ICFP 2012. The Haskell Symposium is for the publication of Haskell-related research. In contrast, the Haskell Implementors' Workshop will have no proceedings -- although we will aim to make talk videos, slides and presented data available with the consent of the speakers. In the Haskell Implementors' Workshop, we hope to study the underlying technology. We want to bring together anyone interested in the nitty-gritty details behind turning plain-text source code into a deployed product. Having said that, members of the wider Haskell community are more than welcome to attend the workshop -- we need your feedback to keep the Haskell ecosystem thriving. The scope covers any of the following topics. There may be some topics that people feel we've missed, so by all means submit a proposal even if it doesn't fit exactly into one of these buckets: * Compilation techniques * Language features and extensions * Type system implementation * Concurrency and parallelism: language design and implementation * Performance, optimisation and benchmarking * Virtual machines and run-time systems * Libraries and tools for development or deployment Talks ----- At this stage we would like to invite proposals from potential speakers for a relatively short talk. We are aiming for 20 minute talks with 10 minutes for questions and changeovers. We want to hear from people writing compilers, tools, or libraries, people with cool ideas for directions in which we should take the platform, proposals for new features to be implemented, and half-baked crazy ideas. Please submit a talk title and abstract of no more than 200 words to: johan.tibell(a)gmail.com We will also have a lightning talks session which will be organised on the day. These talks will be 2-10 minutes, depending on available time. Suggested topics for lightning talks are to present a single idea, a work-in-progress project, a problem to intrigue and perplex Haskell implementors, or simply to ask for feedback and collaborators. Organisers ---------- * Lennart Augustsson (Standard Chartered Bank) * Manuel M T Chakravarty (University of New South Wales) * Gregory Collins - co-chair (Google) * Simon Marlow (Microsoft Research) * David Terei (Stanford University) * Johan Tibell - co-chair (Google)

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ANNOUNCE: control-monad-loop 0.1
by Joey Adams 09 Jul '12

09 Jul '12

This package provides imperative-style loops supporting "continue" and "break". For example: import Control.Monad import Control.Monad.IO.Class import Control.Monad.Trans.Loop import Control.Monad.Trans.Class main :: IO () main = foreach [0..] $ \i -> foreach [0..] $ \j -> do when (j == 0) $ continue -- skip to next iteration when (j >= 5) $ exit -- exit the loop when (i >= 5) $ lift exit -- exit the outer loop by calling 'exit' in the parent monad liftIO $ print (i, j) It works by having the loop body run under the LoopT monad transformer, which provides early exit functions 'continue' and 'exit'. Functions like 'foreach' and 'while' run a LoopT callback, passing it continuations defining 'continue' and 'exit'. http://hackage.haskell.org/package/control-monad-loop

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Reminder: HacPhi 2012 registration closing in two weeks
by wagnerdm＠seas.upenn.edu 08 Jul '12

08 Jul '12

Hello all, HacPhi 2012 is drawing near! To help us finalize the arrangements, we plan on closing the registration period on Friday, July 20, 2012 at 1430 local time (local to you!) ...two weeks before the beginning of the festivities. If you plan on coming, please drop us a line so that we know how many people to provide food and wireless for (and we all know which of those two is the more important ;-). Full instructions for registering are available on the wiki page [1], as well as information about making hotel and travel arrangements. The HacPhi wiki [2] has full details, but the skinny is this: we kick off at 1430 on Friday, August 3, and will hack together for three days (until August 5), with breaks for food and sleep. We will have a time for short talks as well -- let us know if you're interested in telling us a bit about your latest exploits. Whether you're a raw recruit or a grizzled code veteran, come join your Haskell-y comrades-in-arms for a weekend of hacking and fun! - The HacPhi team Brent Yorgey (byorgey) Daniel Wagner (dmwit) Chris Casinghino (ccasin) [1] http://www.haskell.org/haskellwiki/Hac_%CF%86/Register [2] http://www.haskell.org/haskellwiki/Hac_%CF%86

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ANNOUNCE: lens-family-th 0.1.0.0
by Dan Burton 07 Jul '12

07 Jul '12

Following the announcement of lens-family, I'm pleased to announce lens-family-th 0.1.0.0, a Template Haskell library supplying macros to generate lens-family lenses for fields of data types declared with record syntax. Be warned that currently, type signatures are *not* generated alongside the lens definitions. Type inference should correctly determine the type of the generated lenses, but I have structured the library code so that in the future, type signatures can also be generated. Patches welcome! http://hackage.haskell.org/package/lens-family-th -- Dan Burton

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