September 2005 - Haskell

Haskell-mode 2.0
by Stefan Monnier 02 Feb '09

02 Feb '09

I have recently taken over maintainership of Haskell-mode, and after making a bunch of changes, I figured it would be a good idea to make a new release. You can find this new release at: http://www-perso.iro.umontreal.ca/~monnier/elisp/ If you think it should also be found at http://www.haskell.org/haskell-mode/, then please tell John Peterson to get back to me (my email to him seem to go straight to the bitbucket. John?). This release has several changes that have all been only lightly tested, especially w.r.t compatibility with various Emacsen. See appended the NEWS file that describes some of the notewirthy changes. Stefan Changes since 1.45: * keybindings C-c <char> have been replaced by C-c C-<char> so as not to collide with minor modes. * The following modules are now automatically activated without having to add anything to haskell-mode-hook: haskell-font-lock (just turn on global-font-lock-mode). haskell-decl-scan (just bind `imenu' to some key). * In recent Emacsen, haskell-doc hooks into eldoc-mode. * haskell-hugs and haskell-ghci are superceded by inf-haskell. * Indentation rules have been improved when using layout inside parens/braces. * Symbols like -> and \ can be displayed as actual arrows and lambdas. See haskell-font-lock-symbols. * Tweaks to the font-lock settings. Among other things paren-matching with things like \(x,y) should work correctly now. * New maintainer <monnier(a)gnu.org>.

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Literal for Infinity
by Yitzchak Gale 03 Oct '05

03 Oct '05

While checking for floating-point overflow and underflow conditions, I tried to create a somewhat reliable cross-platform Infinity with the literal "1e100000". When GHC 6.4.1 reads this literal, it goes into a deep trance and consumes huge amounts of memory. Shouldn't it immediately recognize such a thing as Infinity? Is there a better way to check for Infinity? I have not yet figured out how to check for NaN at all - because it is not equal to itself. Any suggestions? BTW, I notice that Simon PJ proposed literals for Infinity and Nan several years ago: http://www.haskell.org/pipermail/haskell/2001-August/007753.html Did anything ever come out of this? Regards, Yitzchak

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Haskell Weekly News: September 27, 2005
by John Goerzen 28 Sep '05

28 Sep '05

Haskell Weekly News: September 27, 2005 Greetings, and thanks for reading the ninth issue of HWN, a weekly newsletter for the Haskell community. Each Tuesday, new editions will be posted (as text) to [1]the Haskell mailing list and (as HTML) to [2]The Haskell Sequence. 1. http://www.haskell.org/mailman/listinfo/haskell 2. http://sequence.complete.org/ New Releases * GHC 6.4.1 for MacOS X. Wolfgang Thaller [3]announced the availability of a binary GHC 6.4.1 package for MacOS X. 3. http://article.gmane.org/gmane.comp.lang.haskell.general/12182 * ghc-api 0.1.0. Lemmih [4]announced ghc-api, a cabalization of the GHC 6.5 API. It is currently used by hIDE. 4. http://article.gmane.org/gmane.comp.lang.haskell.general/12166 Discussion Haskell Team Winns ICFP! Congratulations to Wolfgang Thaller's team for winning the ICFP 2005 programming contest! According to the [5]ICFP homepage, "First prize goes to KiebererAndXiaoTou. The judges are happy to proclaim that Haskell is the programming tool of choice for discriminating hackers." This is the second year in a row in which a team using Haskell has taken first place in this contest. 5. http://icfpc.plt-scheme.org/ The Combat-Tanteidan team (Takayuki Muranushi and Hideyuki Tanaka), also using Haskell, took third place in this year's ICFP. In addition, on page 68 of the [6]presentation slides, you can see that Haskell was the top-performing language at the contest overall. The author wrote, "The clear fact that stands out here is that Haskell is the language of choice for the programming contest. Haskell stands out a little bit in the first round, but it clearly stands out in the twist. So, kudos to the Haskell community for both producing a language that lets people build re-usable code and instilling this as a value in their community!" 6. http://icfpc.plt-scheme.org/icfpc2005-talk.pdf Unfortunately, the names of all team members were not documented, so I was not able to list the real names for this story. Thanks to Don Stewart for sending me information about this. Haskell-style proof tools. Robin Green asked about proof tools, and the resulting [7]thread contained several suggestions. 7. http://thread.gmane.org/gmane.comp.lang.haskell.cafe/8451 Trapped by Monads. In this [8]thread, the infamous IO monad was discussed, along with a number of comparisons to Forth. 8. http://thread.gmane.org/gmane.comp.lang.haskell.cafe/8427 Quote of the Week Haskell is the programming tool of choice for discriminating hackers. -- ICFP 2005 judges About Haskell Weekly News Want to continue reading HWN? Please help us create new editions of this newsletter. Please see the [9]contributing information, or send stories to hwn -at- complete -dot- org. There is also a Darcs repository available. 9. http://sequence.complete.org/hwn-contrib

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ANNOUNCE: Visual Haskell version 0.0
by Simon Marlow 27 Sep '05

27 Sep '05

The Visual Haskell team are proud to announce the first preview release of Visual Haskell, version 0.0. Visual Haskell is a complete development environment for Haskell software, based on Microsoft's Visual Studio platform. Visual Haskell integrates with the Visual Studio editor to provide interactive features to aid Haskell development, and it enables the construction of projects consisting of multiple Haskell modules, using the Cabal building/packaging infrastructure. Visual Haskell is a complete system in one download: it includes a full GHC installation with libraries, and various tools including Haddock, Happy, and Alex. In order to use Visual Haskell, you need an x86 machine running Windows, and Visual Studio .NET 2003. Downloads, screenshots and documentation here: http://www.haskell.org/visualhaskell/ Please note that this is a preview release - please download and try it out, but don't expect a production quality experience. We'll be grateful for any feedback you have. A quick note about the license: this is a binary release with a BSD license. We changed the license at the last minute, and didn't have time to re-roll the installer. You have the option of using Visual Haskell either under the click-through license in the installer (a Microsoft shared source license for non-commercial use) or the more liberal BSD license in the documentation. Enjoy! Simon Marlow Krasimir Angelov (with thanks to the others who have contributed to Visual Haskell in the past and to the huge amount of external software on which it relies).

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IO functions reference?
by Creighton Hogg 27 Sep '05

27 Sep '05

Hi, I've been trying to write some code in Haskell and have been running into trouble not knowing the already built-in IO functions. For example, is there a function that will take a line and turn it into a list? Is there a reference where one can lookup all these things? Thanks, Creighton Hogg

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FMCO 2005: first call for participation
by M.M. Bonsangue 27 Sep '05

27 Sep '05

Our apologies if you receive multiple copies of this e-mail. ****************** FIRST CALL FOR PARTICIPATION ******************** Fourth International Symposium on Formal Methods for Components and Objects (FMCO 2005) DATES 1 - 4 November 2005 PLACE CWI, Amsterdam, The Netherlands Registration form and more information at the FMCO site http://fmco.liacs.nl/fmco05.html PRELIMINARY PROGRAM Tuesday November 1st -------------------- SESSION: ALGEBRAIC METHODS 9:00 - 10:00 Keynote: Davide Sangiorgi (University of Bologna, IT) The Bisimulation Proof Method: Enhancements and Challenges Break 10:20 - 11:10 Expressiveness via Leader Election Problems C. Palamidessi (INRIA Futurs Saclay and LIX , FR) Break 11:30 - 12:30 Keynote: Wan Fokkink (Free University, NL) Divide and Congruence Lunch break SESSION: COMPONENT AND SERVICE ORIENTED PROGRAMMING 14:30 - 15:00 Keynote: Kung-Kiu Lau (University of Manchester, UK) Towards a Theory of Software Components Break 15:20 - 16:10 Keynote: Luís Caires (New University of Lisbon, PT) t.b.a. 16:10 - 17:00 Synchronized Hyperedge Replacement as a Model for Service Oriented Computing D. Hirsch (Pisa University, IT) Welcome reception Wednesday November 2nd ---------------------- SESSION: HEAP VERIFICATION 9:30 - 10:30 Keynote: Peter O' Hearn (Queen Mary University of London, UK) Smallfoot: A Tool for Checking Separation Logic Footprint Specifications Break 11:10 - 12:00 Keynote: Joost-Pieter Katoen (RWTH Aachen, DE) Verifying Liveness and Safety of Concurrent Heap-Manipulating Programs Lunch break SESSION: TOOLS 13:30 - 14:30 Keynote: Dennis Dams (Bell Labs, USA) Orion: Building Blocks for Program Analyzers Break 14:50 - 16:00 mCRL2: a language and toolset for behavioural modelling and analysis J.-F. Groote (Technical University Eindhoven, NL) Social event and dinner Thursday Nov 3rd ---------------- SESSION: MODEL CHECKING 9:00 - 10:00 Keynote: Orna Grumberg (Technion, ISR) Abstraction and Refinement in Model Checking Break 10:20 - 11:10 Verification of Evolving Software via Component Substitutability Analysis N. Sinha (Carnegie Mellon University, USA) 11:10 - 12:00 Distributed Analysis of Large Systems L. Brim (University Brno, CZ) Lunch break SPECIAL SESSION 13:30 - 14:30 Keynote: John Reynolds (Carnegie Mellon University, USA) t.b.a. Break SESSION: QUANTITATIVE ANALYSIS 14:50 15:40 Quantitative Aspects of Coordination H. Wiklicky (Imperial College London, UK) 15:40 - 16:30 Partial Order Reduction for Markov Decision Processes C. Baier (Bonn University, DE) Friday Nov 4th -------------- SESSION: ASSERTIONAL METHODS 9:00 - 10:00 Keynote: Arnd Poetzsch-Heffter (University of Kaiserslautern, DE) t.b.a. Break 10:20 - 11:10 Beyond Hoare Logic Assertions: Advanced Specification and Verification with JML and ESC/Java2 J. Kiniry (UCD Dublin, IE) Break 11:30 - 12:30 Keynote: Michael Barnett (Microsoft, USA) t.b.a. Lunch break SESSION: SYSTEM DESIGN 14:00 - 15:00 Keynote: Jan van Schuppen (CWI, NL) Decentralized and Modular Control of Discrete-Event Systems Break 15:20 - 16:10 Formal Development of Critical Systems with UML: Methods and Tools J. Jürjens (Technical University Munich, DE) 16:10 - 17:00 UpSTAIRS with Sequence Diagrams K. Stølen (SINTEF ICT, NO) Farewell drink ORGANIZING COMMITTEE F.S. de Boer (CWI and LIACS-Leiden University) M.M. Bonsangue (LIACS-Leiden University) S. Graf (Verimag) W.P. de Roever (CAU)

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2nd Call for Participation: IFM 2005
by Graeme Smith 27 Sep '05

27 Sep '05

2nd CALL FOR PARTICIPATION Fifth International Conference on Integrated Formal Methods (IFM) November 30 - December 2, 2005 Eindhoven, The Netherlands http://www.win.tue.nl/ifm/ INVITED SPEAKERS Patrice Godefroid - Software Model Checking: Searching for Computations in the Abstract or the Concrete David Parnas - A Family of Mathematical Methods for Professional Software Documentation Doron Peled - Generating Path Conditions for Timed Systems INVITED TUTORIAL Holger Hermanns - QoS Modelling and Analysis for Embedded Systems PROGRAM The program is now available on the IFM2005 web site. DOCTORAL SYMPOSIUM PhD students are invited to submit a contribution on their current research in integrated formal methods. The symposium will take place in Eindhoven on November 29, right after the tutorial by Holger Hermanns, and one day before the main conference (Nov 30 - Dec 2). For details please check the IFM2005 web site: http://www.win.tue.nl/ifm/. VENUE IFM2005 is hosted by the Technische Universiteit Eindhoven (TU/e). Eindhoven is the largest city of the southern Netherlands and the fifth largest in the Netherlands as a whole. It is a diverse city offering innovation and technology, as well as cultural activities (museums, theatre and music), and leading in sports such as swimming (Olympic champion Pieter van den Hoogenband) and soccer (PSV). In the region of Eindhoven, well-known companies such as Philips, ASML and DAF, and dozens of other engineering companies are situated. Eindhoven and the TU/e campus are easily reachable by plane (Eindhoven Airport) and train (also from Schiphol Airport). REGISTRATION At the IFM web site, the registration page can be found. The early registration deadline is October 16th, 2005. The registration fee includes a copy of the proceedings, attendance of the tutorial and the main conference, lunches, refreshments in the coffee breaks, a welcome reception, an excursion and dinner banquet. PROGRAM COMMITTEE CO-CHAIRS Jaco van de Pol, CWI, The Netherlands Judi Romijn, Eindhoven University of Technology, The Netherlands Graeme Smith, University of Queensland, Australia SPONSORS IFM2005 is sponsored by FME and BCS-FACS.

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Haskell Interfacing With VB
by Craig Middlemast 26 Sep '05

26 Sep '05

Hello, I computing student entering my final year at Northumbria University, Newcastle upon Tyne. I am doing some research for my final year project which is to design and build a Syntax Directed Editor for a high level computing language. The problem which I have is that I would like to use VB as a user interface and Haskell as the parser, however I am not sure if this is possible. Therefore I was hoping that you could answer the question regarding Haskell and VB interfacing, is it possible to interface the two languages, and if so could you give me some insight how this can be achieved. Regards Craig Middlemast

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Re: [Haskell] Paper: The essence of dataflow programming
by Tarmo Uustalu 26 Sep '05

26 Sep '05

Dear Dave, Thanks for the nice propaganda! A few comments regarding the points you made in your message. Ineffeciency of fibo-like programs: Your observations are true. But this is a comonadic interpreter analogous to the cbv monadic interpreter. One can also define an analogue to the cbn monadic interpreter. This is better than the "cbv" version on the n first Fibonacci numbers but worse on the nth number alone... Zippers: Yes, of course! Streams are an infinite linear datastructure, but you can also do trees (eg decorated parse trees of a CFG). Such trees with a distinguished position are of course the zipper datatype and this is a comonad as well. And similarly to the comonadic approach to the semantics of dataflow languages one can give a comonadic structure eg to attribute grammar specifications (either purely synthesized attribute grammars or general attribute grammars). We've developed these ideas in a paper that was presented at TFP, see http://www.cs.ioc.ee/~tarmo/papers/tfp05.pdf (this is the symposium version, the full version is in preparation.) To present the comonadic semantics of attribute grammar specifications neatly, one needs either GADTs or dependent types. Best wishes, Tarmo U

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ICTCS 2005: Call for participation
by g. michele pinna 26 Sep '05

26 Sep '05

Ninth Italian Conference on Theoretical Computer Science (ICTCS'05) Certosa di Pontignano (Siena), Italy October 12 - 14, 2005 http://ictcs05.dsmi.unisi.it Call for Partecipation The Ninth Italian Conference on Theoretical Computer Science will take place at the Certosa di Pontignano (Siena), Italy. There will be three invited speakers: Luca Cardelli (Microsoft Research, Cambridge, United Kingdom) Giuseppe Castagna (LIENS - École Normale Supérieure, Paris, France) Nicola Santoro (School of Computer Science, Carleton University, Ottawa, Canada) Program Committee: Michele Bugliesi (Venezia), Mario Coppo (Torino, Co-Chair), Pierluigi Crescenzi (Firenze), Giulia Galbiati (Pavia) Luisa Gargano (Salerno), Giorgio Ghelli (Pisa), Roberto Grossi (Pisa), Benedetto Intrigila (L'Aquila), Nicola Leone (Cosenza), Elena Lodi (Siena, Co-Chair), Flaminia Luccio (Trieste), Andrea Masini (Verona), Giancarlo Mauri (Milano), Corrado Priami (Trento), Geppino Pucci (Padova), Davide Sangiorgi (Bologna). Preliminary program: Wednesday, October 12: 08,45 - 09,00 Welcome 09,00 - 10,00 L. Cardelli: Biological System as Reactive Systems 10,00 - 11,00 B. DasGupta, S. Ferrarini, U. Gopalakrishnan, N. Paryani: Inapproximability Results for the Lateral Gene Transfer Problem S. Mantaci, A. Restivo, G. Rosone, M. Sciortino: A new combinatorial approach to sequence comparison 11,00 - 11,20 coffee break 11,20 - 13,20 M. Bartoletti, P. Degano, G. L. Ferrari: Checking Risky Events is Enough for Local Policy B. Aziz, D. Gray, G. Hamilton: A Static Analsis of PKI-Based Systems R. Medel, A. Compagnoni, E. Bonelli: A Typed Assembly Language for Non-interference L. Bettini, V. Bono, S. Likavec: Safe Object Composition in the Presence of Subtyping 13,20 - 15,00 Lunch 15,00 - 17,00 L. A. Hemaspaandra, J. Rothe, A. Saxena: Enforcing and Defying Associativity, Commutativity, Totality, and Strong Noninvertibility for One-Way Functions in Complexity Theory J. Fiala, J. Kratochvil: On the computational complexity of the L(2,1)-labeling problem for regular graphs B. Escoffier, J. Monnot, V. T. Paschos: Weighted coloring: further complexity and approximability results V. Raman, S. Saurabh, S. Sikdar: Improved Exact Exponential Algorithms for Vertex Bipartization and Other Problems 17,00 - 17,20 coffee break 17,20 - 19,20 S. van Bakel, U. de' Liguoro: Subtyping Object and Recursive Types Logically J. Schwinghammer: A Typed Semantics of Higher Order Store and Subtyping W. Jamroga, J. Dix: Model Checking Strategic Abilities of Agents under Incomplete Information S. Heymans, D. Van Nieuwenborgh, D. Vermeir: Synthesis from Temporal Specifications using Preferred Answer Set Programming 20,00 - Dinner Thursday, October 13: 09,00 - 10,00 N. Santoro: Mobile Agents Computing: Security Issues and Algorithmic Solutions 10,00 - 11,00 T. Kuboyama, K. Shin, T. Miyahara, H. Yasuda: A Theoretical Analysis of Alignment and Edit Problems for Trees L. Anderegg, M. Cieliebak, G. Prencipe: Efficient Algorithms for Detecting Regular Point Configurations 11,00 - 11,20 coffee break 11,20 - 13,20 R. Statman: Two Variables are Not Enough S. van Bakel, S. Lengrand, P. Lescanne: The language X: Circuits, Computations and Classical Logic C. Bertolissi: The Graph Rewriting Calculus: confluence and Expressiveness N. Busi, G. Zavattaro: Reachability Analysis in Boxed Ambients 13,20 - 15,00 Lunch 15,15 - 17,15 G. De Marco, M. Pellegrini, G. Sburlati: Faster Deterministic Wakeup in Multiple Access Channels M-C. Costa, F. Jarray, C. Picoleau: Reconstructing an alternate periodical binary matrix from its orthogonal projections S. Fung, F. Chin, C. K. Poon: Laxity helps in broadcast scheduling Y. Asahiro, E. Miyano, S. Shimoirisa: Pickup and Delivery for Moving Objects on Broken Lines 17,30 - Excursion to Siena 18,00 - 20,00 EATCS Italian Chapter Annual Meeting (at the Dipartimento di Scienze Matematiche e Informatiche "R. Magari" 20,30 - Social dinner Friday, October 14: 09,00 - 10,00 G. Castagna: Semantic Subtyping: challenges, perspectives and open problems 10,00 - 11,00 G. Castagna, D. Colazzo, A. Frish: Error Mining for Regular Expressions Patterns M. Macchetti, M. Caironi, L. Breveglieri, A. Cherubini: A Complete Formulation of Generalized Affine Equivalence 11,00 - 11,30 coffee break 11,30 - 13,00 T. Kopelowitz, E. Porat: Improved Algorithms for Polynomial Time-Decay and Time-Decay with Additive error S. Fenner, Y. Zhan: Quantum Algorithms for a Set of Group Theoretic Problems G. Franco: A polymerase based algorithm for SAT 13,00 - 13,20 End of the Conference 13,20 Lunch Registration The registration form is available at http://ictcs05.dsmi.unisi.it/registration.html or at the web page http://conference.unisi.it/gest-congressi/web/online_ing.asp?id_cong=670 Here is a list of hotels with web sites Hotel Athena (4 stars): http://www.hotelathena.com Hotel Garden (4 stars): http://www.garden-hotels.it/it/garden/garden.html Hotel Italia (3 stars): http://www.garden-hotels.it/it/italia/italia.html Hotel Palazzo Ravizza (3 stars): http://www.palazzoravizza.it/ Hotel Minerva (3 stars): http://www.emmeti.it/Welcome/Toscana/Senese/Siena/Alberghi/Minerva/ Hotel Duomo (3 stars): http://www.hotelduomo.it/ Hotel Etruria (2 stars): http://www.hoteletruria.com Piccolo Hotel il Palio (2 stars): http://www.minotel.com/minotelPublic/main/basicHotelInfo.asp?hotelCode=IT107 Hotel Cannon D'Oro (2 stars): http://www.cannondoro.com Booking can also be made via the Siena Hotels Promotion - Congress & Meeting Dept. email: congressi(a)hotelsiena.com http://www.hotelsiena.com Piazza M.T. di Calcutta, 5 - 53100 Siena - Italy Tel. 0039+0577+288084 - Fax. 0039+0577+280290 Please quote ICTCS conference in the request. Further informations are available at the conference web pages.

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