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ICFP07 Reminder: registration deadline
by Matthew Fluet (ICFP Publicity Chair) 05 Sep '07

05 Sep '07

===================================================================== Final Call for Participation The 12th ACM SIGPLAN International Conference on Functional Programming (ICFP 2007) http://www.informatik.uni-bonn.de/~ralf/icfp07.html http://proglang.informatik.uni-freiburg.de/ICFP2007 Freiburg, Germany, 1-3 October 2007 ===================================================================== ***** Early Registration Deadline: September 7, 2007 ***** ICFP 2007 provides a forum for researchers and developers to hear about the latest work on the design, implementations, principles, and uses of functional programming. The conference covers the entire spectrum of work, from practice to theory, including its peripheries. Schedule including related workshops: * 30 Sep: ACM SIGPLAN Haskell Workshop * 30 Sep: ACM SIGPLAN Workshop on Scheme and Functional Programming * 1-3 Oct: ICFP07 * 4 Oct: ACM SIGPLAN Commercial Users of Functional Programming * 4 Oct: ACM SIGPLAN Workshop on Mechanizing Metatheory * 5 Oct: ACM SIGPLAN Erlang Workshop * 5 Oct: ACM SIGPLAN Workshop on ML * 5 Oct: ACM SIGPLAN Programming Languages meets Program Verification

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ANNOUNCE: xmonad 0.3
by dons＠cse.unsw.edu.au 05 Sep '07

05 Sep '07

The xmonad dev team is pleased to announce the 0.3 release of xmonad. xmonad: a tiling window manager http://xmonad.org About: xmonad is a tiling window manager for X. Windows are arranged automatically to tile the screen without gaps or overlap, maximising screen use. All features of the window manager are accessible from the keyboard: a mouse is strictly optional. xmonad is written and extensible in Haskell. Custom layout algorithms, and other extensions, may be written by the user in config files. Layouts are applied dynamically, and different layouts may be used on each workspace. Xinerama is fully supported, allowing windows to be tiled on several screens. Features: * Very stable, fast, small and simple. * Automatic window tiling and management * First class keyboard support: a mouse is unnecessary * Full support for tiling windows on multi-head displays * Full support for floating windows * XRandR support to rotate, add or remove monitors * Per-workspace layout algorithms * Per-screens custom status bars * Easy, powerful customisation and reconfiguration * Large extension library * Extensive documentation and support for hacking Since xmonad 0.2, the following notable features and bug fixes have appeared: New features: * floating layer support: transients windows are not tiled by default, and windows may be dragged to and from a traditional floating layer (which allows mouse-resizing, and overlapping windows). * improved Xinerama support: workspace switching reuses multiple displays more effectively. * huge new extension library. Over 50 extensions to xmonad have been contributed by users, and are available all in a standard library, with documentation. More information, screenshots, documentation and community resources are available from: http://xmonad.org Xmonad is available from hackage, and via darcs. Happy hacking! The Xmonad Team: Spencer Janssen Don Stewart Jason Creighton Xmonad has also received contributions from at least: Alec Berryman Andrea Rossato Chris Mears Daniel Wagner David Glasser David Lazar David Roundy Hans Philipp Annen Joachim Fasting Joe Thornber Kai Grossjohann Karsten Schoelzel Michael Sloan Miikka Koskinen Neil Mitchell Nelson Elhage Nick Burlett Peter De Wachter Robert Marlow Sam Hughes Shachaf Ben-Kiki Shae Erisson Simon Peyton Jones Stefan O'Rear as well as many others on the IRC channel and mailing list. Thanks to everyone!

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functional dependencies not satisfactory?
by Wolfgang Jeltsch 05 Sep '07

05 Sep '07

Hello, I came across the following problem: I define a class with a functional dependency like so: class C a b | a -> b Then I want to define a datatype using the fact that the second argument of C is dependent on the first: data C a b => T a = MkT a b But unfortunately, this doesn’t work, at least not in GHC. I can try this: data T a = forall b. C a b => MkT a b But if I do pattern matching on a value of T a, GHC doesn’t recognize that the type of MkT’s second argument is determined by the type of the first. For example, the following function definition is not accepted: useB :: C a b => T a -> (b -> ()) -> () useB (MkT a b) f = f b In my opinion, the problem is that GHC doesn’t see that because of the functional dependency the type exists b. C a b => b is at least as general as the type forall b. C a b => b. Is there a solution to this problem? Best wishes, Wolfgang

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ISMM'07: call for participation
by Greg Morrisett 04 Sep '07

04 Sep '07

ISMM'07 CALL FOR PARTICIPATION and Accepted Papers 2007 ACM International Symposium on Memory Management co-located with OOPSLA 2007 Sponsored by ACM SIGPLAN 21-22 October 2007, Montreal http://www.eecs.harvard.edu/~greg/ismm07/ To register for the symposium, see the OOPSLA registration page at http://www.oopsla.org/oopsla2007. Note that the deadline for early registration and reduced rates is Thursday, 13 September. ISMM is a forum for research in management of dynamically allocated memory. Areas of interest include but are not limited to: explicit storage allocation and deallocation; garbage collection algorithms and implementations; compiler analyses to aid memory management; interactions with languages, operating systems, and hardware, especially the memory system; and empirical studies of allocation and referencing behavior in programs that make significant use of dynamic memory. This year's symposium is being held in conjunction with OOPSLA in Montreal on October 21st and 22nd. Invited speakers include Peter O'Hearn (Queen Mary, University of London) and David Kirk (Chief Scientist NVIDIA). In addition to presentation of the papers listed below, there will be an exciting "wild and crazy" ideas session where participants will have a chance to discuss half-baked and interesting ideas. All are welcome! Invited talks and papers to be presented at the symposium: Keynote: Separation Logic and Concurrent Resource Management Peter O'Hearn Safe Manual Memory Management David Gay, Robert Ennals, & Eric Brewer Detecting and Eliminating Memory Leaks Using Cyclic Memory Allocation Huu Hai Nguyen & Martin Rinard Page Access Tracking to Improve Memory Management Reza Azimi, Livio Soares, Michael Stumm, Angela Demke Brown, & Tom Walsh Effective Prefetch for Mark-Sweep Garbage Collection Robin Garner, Stephen Blackburn, & Daniel Frampton Accordion Arrays: Selective Compression of Unicode Arrays in Java Craig Zilles Decrypting the Java Gene Pool: Predicting Object Lifetimes with Micro- Patterns Sebastien Marion, Richard Jones, & Chris Ryder Allocation-Phase Aware Scheduling Policies to Improve Garbage Collection Performance Feng Xian, Witawas Srisa-an, & Hong Jiang Intelligent Selection of Application-Specific Garbage Collectors Jeremy Singer, Gavin Brown, Ian Watson, & John Cavazos Keynote: NVIDIA CUDA Software and GPU Parallel Computing Architecture David Kirk Heap Space Analysis for Java Bytecode Elvira Albert, Samir Genaim, & Miguel Gomez-Zamalloa Uniqueness Inference for Compile-Time Object Deallocation Sigmund Cherem & Radu Rugina A Correct and Useful Incremental Copying Garbage Collector Martin Kero, Johan Nordlander, & Per Lindgren Overlooking Roots: A Framework for Making Nondeferred Reference- Counting Garbage Collection Fast Pramod Joisha Stopless: A Real-Time Garbage Collector for Modern Platforms Filip Pizlo, Daniel Frampton, Erez Petrank, & Bjarne Steensgaard Mark-Sweep or Copying? A "Best of Both Worlds" Algorithm and a Hardware-Supported Real-Time Implementation Sylvain Stanchina & Matthias Meyer

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APLAS07 - Call for Participation
by Corneliu Popeea 31 Aug '07

31 Aug '07

Call for Participation The Fifth Asian Symposium on Programming Languages and Systems November 29 - December 1, 2007 Singapore http://www.comp.nus.edu.sg/~aplas07/ http://flint.cs.yale.edu/aplas2007/ Scope of the Conference ----------------------- APLAS aims at stimulating programming language research by providing a forum for the presentation of recent results and the exchange of ideas and experience in topics concerned with programming languages and systems. APLAS is based in Asia, but is an international forum that serves the worldwide programming languages community. The APLAS series is sponsored by the Asian Association for Foundation of Software (AAFS), which has recently been founded by Asian researchers in cooperation with many researchers from Europe and the USA. The past formal APLAS symposiums were successfully held in Sydney (2006, Australia), Tsukuba (2005, Japan), Taipei (2004, Taiwan) and Beijing (2003, China) after three informal workshops held in Shanghai (2002, China), Daejeon (2001, Korea) and Singapore (2000). Proceedings of the past symposiums were published in Springer-Verlag's LNCS 2895, 3302, 3780, and 4279. Conference Location ------------------- APLAS'07 will be held at Kent Ridge Guild House, National University of Singapore. Singapore is a dynamic city rich in contrast and color where you'll find a harmonious blend of culture, cuisine, arts and architecture. A bridge between the East and the West for centuries, Singapore, located in the heart of fascinating Southeast Asia, continues to embrace tradition and modernity today. Brimming with unbridled energy and bursting with exciting events, the city offers countless unique, memorable experiences waiting to be discovered. Registration ------------ The early registration deadline is set on 28Sept07. The registration fees will cover conference proceeding, banquet dinner, and lunches/teas. Deadline Full Fees Student Fees early 28Sep07 S$600 S$400 online 23Nov07 S$650 S$425 on-site 29Nov07 S$700 S$450 Payment can be made with credit cards. Exchange rate (subject to fluctuation) is approx. US$1 = S$1.53 Online registration can be made at: http://www.comp.nus.edu.sg/~aplas07/local.html#registration Accommodation ------------- A special rate S$155 per nite (excluding taxes but inclusive of daily breakfast) is applicable to attendees of APLAS 2007 at Rendezvous Hotel Singapore: http://www.rendezvoushotels.com/singapore/ The hotel is located in city center. A free daily shuttle bus will be provided between this hotel and the conference site (at NUS) during the conference period. Our block of rooms is guaranteed till 28Sept07, so advanced booking is encouraged as some rooms may be released after this date. For reservation, please use a special form that can be found at: http://www.comp.nus.edu.sg/~aplas07/Hotel.APLAS07.pdf Poster Session -------------- APLAS07 will include a poster session. Submission deadline is 14 Sept 2007. For details, please see: http://www.comp.nus.edu.sg/~aplas07/posters.html Conference Program ------------------ 29 Nov (Thu) ------------ 915- 930 Opening note 930-1030 Invited Talk X10: Programming Parallel Machines, Productively Vijay Saraswat (IBM TJ Watson Research Lab) 1100-1230 Session 1 The Nuggetizer: Abstracting Away Higher-Orderness for Program Verification Paritosh Shroff (Johns Hopkins University), Christian Skalka (University of Vermont) and Scott F. Smith (Johns Hopkins University) Local Reasoning for Storable Locks and Threads Alexey Gotsman (University of Cambridge), Josh Berdine (Microsoft Research), Byron Cook (Microsoft Research), Noam Rinetzky (Tel Aviv University) and Mooly Sagiv (Tel Aviv University) Monadic, Prompt Lazy Assertions in Haskell Frank Huch (CAU Kiel) and Olaf Chitil (University of Kent) 1345-1515 Session 2 Translation Correctness for First-Order Object-Oriented Pattern Matching Burak Emir (EPFL Lausanne), Qin Ma (OFFIS) and Martin Odersky (EPFL Lausanne) Persistent Oberon: A Programming Language with Integrated Persistence Luc Blaser (ETH Zurich) More Typed Assembly Languages for Confidentiality Dachuan Yu (DoCoMo Communication Laboratories USA) 1515-1630 Poster Session 1630-1730 Session 3 A Novel Test Case Generation Method for Prolog Programs Based on Call Patterns Semantics Lingzhong Zhao (Guilin University of Electronic Technology), Tianlong Gu (Guilin University of Electronic Technology), Junyan Qian (Guilin University of Electronic Technology) and Guoyong Cai (Guilin University of Electronic Technology) On a Tighter Integration of Functional and Logic Programming Frank Huch (CAU Kiel) and Bernd Brassel (CAU Kiel) 1800-2000 Reception 30 Nov (Fri) ------------ 930-1030 Invited Talk Scalable Simulation of Biological Signaling Networks Vincent Danos (University of Paris VII & CNRS) 1100-1230 Session 4 Timed, Distributed, Probabilistic, Typed Processes Martin Berger (Imperial College London) and Nobuko Yoshida (Imperial College London) A Probabilistic Applied Pi-Calculus Jean Goubault-Larrecq (ENS Cachan), Catuscia Palamidessi (Ecole Polytechnique) and Angelo Troina (ENS Cachan & Ecole Polytechnique) Type-Based Verification of Correspondence Assertions for Communication Protocols Daisuke Kikuchi (Tohoku University) and Naoki Kobayashi (Tohoku University) 1400-1530 Session 5 Deriving Compilers and Virtual Machines for a Multi-Level Language Atsushi Igarashi (Kyoto University) and Masashi Iwaki (Kyoto University) Finally Tagless, Partially Evaluated (Tagless Staged Interpreters for Simpler Typed Languages) Jacques Carette (McMaster University), Oleg Kiselyov (FNMOC) and Chung-chieh Shan (Rutgers University) Polymorphic Delimited Continuations Kenichi Asai (Ochanomizu University) and Yukiyoshi Kameyama (University of Tsukuba) 1600-1730 Session 6 Adjunct Elimination in Context Logic for Trees Cristiano Calcagno (Imperial College London), Thomas Dinsdale-Young (Imperial College London) and Philippa Gardner (Imperial College London) Positive Arithmetic without Exchange is a Subclassical Logic Stefano Berardi (University of Torino) and Makoto Tatsuta (National Institute of Informatics, Japan) Mixed Inductive/Coinductive Types and Strong Normalization Andreas Abel (University of Munich) 1900-2100 Banquet 1 Dec (Sat) ------------ 930-1030 Invited Talk Static and Dynamic Analysis : Better Together Sriram Rajamani (Microsoft Research India) 1100-1230 Session 7 The Semantics of "Semantic Patches" in Coccinelle: Program Transformation for the Working Programmer Neil Jones (University of Copenhagen) and Rene Rydhof Hansen (University of Copenhagen) An Efficient SSA-based Algorithm for Complete Global Value Numbering Jiu-Tao Nie (Peking University) and Xu Cheng (Peking University) A Systematic Approach to Probabilistic Pointer Analysis Alessandra Di Pierro (University of Verona), Chris Hankin (Imperial College London) and Herbert Wiklicky (Imperial College London) 1400-1530 Session 8 Complete Lattices and Up-to Techniques Damien Pous (ENS Lyon) A Trace Based Bisimulation for the Spi Calculus: An Extended Abstract Alwen Tiu (Australian National University) CCS with Replication in the Chomsky Hierarchy: The Expressive Power of Divergence Frank Valencia (Ecole Polytechnique), Cinzia Di Giusto (University of Bologna), Jesus Aranda (Ecole Polytechnique) and Mogens Nielsen (University of Aarhus) 1600-1700 Session 9 Call-by-Name and Call-by-Value in Normal Modal Logic Yoshihiko Kakutani (University of Tokyo) Call-by-Value is Dual to Call-by-Name, Extended Daisuke Kimura (National Institute of Informatics, Japan) 1700-1715 Closing note Organization ------------- GENERAL CHAIR Joxan Jaffar (National University of Singapore, Singapore) PROGRAM CHAIR Zhong Shao (Yale University, USA) PROGRAM COMMITTEE Lars Birkedal (IT University of Copenhagen, Denmark) Martin Hofmann (Univ of Munich, Germany) Kohei Honda (Queen Mary, University of London, UK) Atsushi Igarashi (Kyoto University, Japan) Suresh Jagannathan (Purdue University, USA) Annie Liu (State University of New York at Stony Brook, USA) Shin-Cheng Mu (Academia Sinica, Taiwan) Henrik Nilsson (University of Nottingham, UK) Michael Norrish (NICTA, Australia) Jens Palsberg (University of California, Los Angeles, USA) G. Ramalingam (Microsoft Research, India) Zhendong Su (University of California, Davis, USA) Martin Sulzmann (National University of Singapore, Singapore) Eijiro Sumii (Tohoku University, Japan) Jerome Vouillon (CNRS, France) Kwangkeun Yi (Seoul National University, Korea) Jian Zhang (Chinese Academy of Sciences, China) POSTER SESSION CHAIR Eijiro Sumii (Tohoku University, Japan) LOCAL ARRANGEMENT CHAIR Wei-Ngan Chin (National University of Singapore, Singapore)

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new SOE package and the annoucement of GLFW
by Paul L 30 Aug '07

30 Aug '07

Hi all, After much struggle to bring the SOE source to be compatible with the latest GHC, I'm pleased to announce that it's available at http://www.haskell.org/soe It's has been tested on Windows (both XP and Vista), Linux and Mac OS X under GHC 6.6.1. The code now requires a Haskell package GLFW, an interface to the GLFW OpenGL Framework (http://glfw.sourceforge.net) which is an alternative to GLUT for OpenGL based programs. Most SOE code examples are not affected by this change except that they now make use of the included SOE.hs instead of the previous SOEGraphics module. The SOE.hs now handles all window and drawing activities through GLFW and OpenGL. The music part of SOE code has also been brought up to date. Please help to report bugs or suggestions if you have any. Help is also needed to make the GLFW Haskell package fully compatible with cross-platform Cabal installation steps. Regards, Paul Liu

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ghc as a library and profiling
by Sönke Hahn 29 Aug '07

29 Aug '07

Hi! I am working on a program that uses ghc as a library to typecheck code. I want to profile the program (compiling with '-prof -auto-all' and running with '+RTS -p'). Trying to compile, results in the following message: Could not find module `GHC': Perhaps you haven't installed the profiling libraries for package ghc-6.6.1? I built ghc-6.6.1 from source without changing any configuration files. The building guide (http://hackage.haskell.org/trac/ghc/wiki/Building/QuickStart) says, this would install the compiler WITH profiling libraries. As i understand it, this somehow excludes the ghc package. (Maybe because it is not widely used?) Is this understanding right? Is it possible (and if, how) to compile ghc with a profiling version of the ghc package? I tried to add GhcStage2HcOpts = -Rghc-timing -prof -auto-all GhcStage2LibHcOpts = -prof -auto-all to mk/build.mk, but i am getting the following build error in stage 2: ghc-6.6.1: combination not supported: Threaded/Profiling Do i need to disable thread support? How would i do that? A second idea that comes to my mind is this: The ghc package is hidden in the standard installation, so i unhided (unhid?) it via 'ghc-pkg expose ghc'. Maybe it just exposed the non-profiling version and kept the profiling version hidden? How would i expose both? Any help appreciated... Sönke

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TryTypeCast hackery possible?
by Andreas Schropp 29 Aug '07

29 Aug '07

While reading on Oleg's typeclass-overloaded functions via "local" (*) backtracking (http://okmij.org/ftp/Haskell/poly2.txt) it occured to me that in order to support true Prolog-style instance/clause selection (Oleg seems to only use guards not based on unification-success), one would need TryTypeCast (mixture of TypeCast and TypeEq from HList paper: unify if possible and return HTrue, otherwise return HFalse). After a bit of experimentation my best try is this: -- should i somehow express the "local" functional dependencies -- res=HTrue a -> b and res=HTrue b -> a? class TryTypeCast a b res | a b -> res -- pretending polymorphism in t to prevent early unification of a and b, -- as seen in HLIST paper class TryTypeCast' t a b res | t a b -> res class TryTypeCast'' t a b res | t a b -> res instance TryTypeCast' () a b res => TryTypeCast a b res instance TryTypeCast'' t a b res => TryTypeCast' t a b res instance TryTypeCast'' () a a HTrue instance TypeCast HFalse res => TryTypeCast'' () a b res But it doesnt work (of course? is there even a workaround?) in the interesting cases, as unresolved overlapping gets into my way. (*) it seems that in the current model only "tail-recursive", in the search path sense, only needing local choice between success or search-deepening (the traditional append/3 would be tail-recursive in this way; not sure if this is standard terminology), predicates are possible. How to extend on that? I thought about a history of clause/instance selections per "predicate", hacking up Oleg's GFN-Interpreter in that regard, or even employing type-level CPS, based on the notion of closures in Oleg's Computable Types I (http://www.haskell.org/pipermail/haskell/2006-September/018486.html)

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Sun slots transactional memory into Rock
by Bulat Ziganshin 28 Aug '07

28 Aug '07

Hello haskell, "Hoping to improve the state of server software, Sun Microsystems has confirmed that it will include support for transactional memory with the first generation of its Rock processors due out in the second half of next year." http://www.theregister.com/2007/08/21/sun_transactional_memory_rock/ -- Best regards, Bulat mailto:Bulat.Ziganshin@gmail.com

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Issue about use of WinHugs
by Zhao, Bingfeng 25 Aug '07

25 Aug '07

Hi, list I'm new to WinHugs, what's wrong with isUpper of my WinHugs? Hugs> filter isUpper "ABCDEfgh" ERROR - Undefined variable "isUpper" Hugs> filter Char.isUpper "ABCDEfgh" ERROR - Undefined qualified variable "Char.isUpper" Hugs> :version -- Hugs Version Sep 2006 Best Regards, bingfeng

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