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LOPSTR 2008: Preliminary Call for Papers
by mh＠informatik.uni-kiel.de 21 Dec '07

21 Dec '07

====================================================================== CALL FOR PAPERS 18th International Symposium on International Symposium on Logic-Based Program Synthesis and Transformation LOPSTR 2008 http://www.informatik.uni-kiel.de/~mh/lopstr08/ July 17-18, 2008, Valencia, Spain (co-located with SAS 2008) ====================================================================== Objectives: The aim of the LOPSTR series is to stimulate and promote international research and collaboration on logic-based program development. LOPSTR is open to contributions in logic-based program development in any language paradigm. LOPSTR has a reputation for being a lively, friendly forum for presenting and discussing work in progress. Formal proceedings are produced only after the symposium, so authors can incorporate this feedback in the published papers. Topics: Topics of interest cover all aspects of logic-based program development, all stages of the software life cycle, and issues of both programming-in-the-small and programming-in-the-large. Papers describing applications in these areas are especially welcome. Contributions are welcome on all aspects of logic-based program development, including, but not limited to: specification synthesis verification transformation analysis optimisation composition security reuse applications and tools component-based software development software architectures agent-based software development program refinement Survey papers, that present some aspect of the above topics from a new perspective, and application papers, that describe experience with industrial applications, are also welcome. Papers must describe original work, be written and presented in English, and must not substantially overlap with papers that have been published or that are simultaneously submitted to a journal, conference, or workshop with refereed proceedings. Work that already appeared in unpublished or informally published workshop proceedings may be submitted (please contact the PC chair in case of questions). IMPORTANT DATES AND SUBMISSION GUIDELINES: Paper/extended abstract submission: May 7, 2008 Notification (for pre-proceedings): June 8, 2008 Camera-ready (for pre-proceedings): June 29, 2008 Symposium: July 17-18, 2008 Submissions can either be (short) extended abstracts or (full) papers whose length should not exceed 9 and 15 pages (including references), respectively. Submissions must be formatted in the Springer LNCS style (excluding well-marked appendices not intended for publication). Referees are not required to read the appendices, and thus papers should be intelligible without them. Short papers may describe work-in-progress or tool demonstrations. Both accepted short and full papers will appear in the pre-proceedings. The full papers will automatically appear in the formal proceedings that is expected to be published by Springer-Verlag in the LNCS series. In addition, after the symposium, the programme committee will select those short papers to be considered for formal publication. These authors will be invited to revise and extend their submissions in the light of the comments of the reviewers and the feedback solicited at the meeting. Then after another round of reviewing, the revised papers which are accepted will be also published in the formal proceedings. Papers should be submitted either in PDF or PostScript via the web page of LOPSTR 2008. Program Committee: Slim Abdennadher German University Cairo Danny De Schreye K.U.Leuven, Belgium Wlodek Drabent Polish Academy of Sciences, Poland / Linköping Univ., Sweden Gopal Gupta University of Texas at Dallas, USA Michael Hanus University of Kiel, Germany (Chair) Patricia Hill University of Leeds, UK Andy King University of Kent, UK Michael Leuschel University of Duesseldorf, Germany Torben Mogensen DIKU, University of Copenhagen, Denmark Mario Ornaghi Universita degli Studi di Milano, Italy Etienne Payet Universite de La Reunion, France Alberto Pettorossi University of Rome Tor Vergata, Italy German Puebla Technical University of Madrid, Spain C.R. Ramakrishnan SUNY at Stony Brook, USA Sabina Rossi Universita Ca' Foscari di Venezia, Italy Chiaki Sakama Wakayama University, Japan Josep Silva Technical University of Valencia, Spain Wim Vanhoof University of Namur, Belgium Eelco Visser Delft University of Technology, The Netherlands ----------------------------------------------------------------------

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Re: ANNOUNCE: GHC version 6.8.2
by Claus Reinke 21 Dec '07

21 Dec '07

> With the Windows release of GHC 6.8.2, GHCi does not find .ghci in > %HOME% (though it finds it in the current directory): try %HOMEDRIVE% %HOMEPATH% instead? or the result of 'System.Directory.getHomeDirectory'. you might have set %HOME% to help some unix software along, but this variable doesn't seem to exist by default. claus http://www.microsoft.com/resources/documentation/windows/xp/all/proddocs/en… http://en.wikipedia.org/wiki/Home_directory

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help needed to test new GLFW package
by Paul L 21 Dec '07

21 Dec '07

With the new Cabal 1.2, it's now possible to make platform dependent C code compilation. So I've made available new version of GLFW that follows standard Cabal installation steps, it's at: http://www.cs.yale.edu/homes/hl293/download/GLFW-0.2.tar.gz Note that this is VERY experimental. Help is needed to test the package on different combinations of GHC + OS platforms. I've already tested it on Linux (i386 32bit) + GHC 6.8.2/6.6.1, Windows XP and OS X 10.4 (Intel) + GHC 6.6 (with Cabal 1.2.2). I'll appreciate feedbacks from GHC 6.8/6.6 on Linux (IA64), Windows Vista, and OS X 10.5 (intel) or OS X (ppc). If no major installation problem remains, I'm going to put it up on hackageDB. Thanks! -- Regards, Paul Liu Yale Haskell Group http://www.haskell.org/yale

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ANNOUNCE: Haddock version 0.9
by Simon Marlow 20 Dec '07

20 Dec '07

Announcing the release of Haddock 0.9 http://www.haskell.org/haddock/ http://hackage.haskell.org/cgi-bin/hackage-scripts/package/haddock-0.9 While Haddock 2 is still in development and should be available shortly, this is an updated version of the old Haddock that works with the latest tools and has various other improvements (all of which have also been rolled into Haddock 2). Changes in version 0.9: * Infix type operators, e.g., first :: a~>a' -> (a,b)~>(a',b) * Add a search box to the index page which automatically narrows the index to the search as you type (thanks to Neil Mitchell). * Add a --ghc-pkg flag * Add a flag --allow-missing-html * URL expansion for %%, %L, %{LINE} * added substitution %{FILE///c} * Lexing of /.../ is now more like '...', in that a / character must be matched by another / character on the same line, otherwise it is treated as a literal '/'. This removes a common source of accidental parse errors in documentation. * Various bugs were fixed. * Cabal 1.2 is now required, and Haddock builds with GHC 6.8.x.

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ANNOUNCE: GHC version 6.8.2
by Ian Lynagh 20 Dec '07

20 Dec '07

============================================================= The (Interactive) Glasgow Haskell Compiler -- version 6.8.2 ============================================================= The GHC Team is pleased to announce a new patchlevel release of GHC. This release contains a number of bugfixes relative to 6.8.1, including some significant performance fixes, so we recommend upgrading. Release notes are here: http://haskell.org/ghc/docs/6.8.2/html/users_guide/release-6-8-2.html How to get it ~~~~~~~~~~~~~ The easy way is to go to the web page, which should be self-explanatory: http://www.haskell.org/ghc/ We supply binary builds in the native package format for many platforms, and the source distribution is available from the same place. Packages will appear as they are built - if the package for your system isn't available yet, please try again later. Background ~~~~~~~~~~ Haskell is a standard lazy functional programming language; the current language version is Haskell 98, agreed in December 1998 and revised December 2002. GHC is a state-of-the-art programming suite for Haskell. Included is an optimising compiler generating good code for a variety of platforms, together with an interactive system for convenient, quick development. The distribution includes space and time profiling facilities, a large collection of libraries, and support for various language extensions, including concurrency, exceptions, and foreign language interfaces (C, whatever). GHC is distributed under a BSD-style open source license. A wide variety of Haskell related resources (tutorials, libraries, specifications, documentation, compilers, interpreters, references, contact information, links to research groups) are available from the Haskell home page (see below). On-line GHC-related resources ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Relevant URLs on the World-Wide Web: GHC home page http://www.haskell.org/ghc/ GHC developers' home page http://hackage.haskell.org/trac/ghc/ Haskell home page http://www.haskell.org/ Supported Platforms ~~~~~~~~~~~~~~~~~~~ The list of platforms we support, and the people responsible for them, is here: http://hackage.haskell.org/trac/ghc/wiki/Contributors Ports to other platforms are possible with varying degrees of difficulty. The Building Guide describes how to go about porting to a new platform: http://hackage.haskell.org/trac/ghc/wiki/Building Developers ~~~~~~~~~~ We welcome new contributors. Instructions on accessing our source code repository, and getting started with hacking on GHC, are available from the GHC's developer's site run by Trac: http://hackage.haskell.org/trac/ghc/ Mailing lists ~~~~~~~~~~~~~ We run mailing lists for GHC users and bug reports; to subscribe, use the web interfaces at http://www.haskell.org/mailman/listinfo/glasgow-haskell-users http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs There are several other haskell and ghc-related mailing lists on www.haskell.org; for the full list, see http://www.haskell.org/mailman/listinfo/ Some GHC developers hang out on #haskell on IRC, too: http://www.haskell.org/haskellwiki/IRC_channel Please report bugs using our bug tracking system. Instructions on reporting bugs can be found here: http://www.haskell.org/ghc/reportabug

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problem with hs-plugins 1.1 on Windows: _WaitForSingleObject
by Conal Elliott 17 Dec '07

17 Dec '07

I compiled a fresh darcs-get of the latest hs-plugins (through patch 209). it all compiles fine, but the tests die with complaints like this one: +Main.exe: +c:/ghc/ghc-6.8.1.20071102/lib\base-3.0.0.0/HSbase-3.0.0.0.o: unknown symbol `_WaitForSingleObject' +Main.exe: user error (resolvedObjs failed.) + Other unknown symbols: directory-1.0.0.0/HSdirectory-1.0.0.0.o: unknown symbol `_GetTempPathA' process-1.0.0.0/HSprocess-1.0.0.0.o: unknown symbol `_CloseHandle' One other error: +Main.exe: unloadObj: can't find `c:/ghc/ghc-6.8.1.20071102/lib\old- locale-1.0.0.0/HSold-locale-1.0.0.0.o' to unload +Main.exe: user error (unloadObj: failed) Any suggestions? Thanks, - Conal

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Jobs in Functional Programming: the dust settles
by John Hughes 17 Dec '07

17 Dec '07

The "Jobs in Functional Programming" event at Chalmers is now over-and was a resounding success! So many people preregistered. 111 in total. that I began to worry about the fire regulations for the room we were using! We ran out of chairs, and latecomers were standing around the walls. Six companies sent speakers for the event, and they gave excellent presentations, with many jobs available. All in all, it was a very exciting evening! Photographs and more details can be found at www.jobs-in-fp.org. John Hughes

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South African Computer Olympiad
by Max Rabkin 14 Dec '07

14 Dec '07

Hi Haskellers We have just added support for GHC to the marking system for the South African Computer Olympiad. Therefore, I would like to invite you to join us for our public Training Camp tomorrow. The primary purpose of the competition is to prepare the South African squad for the International Olympiad in Informatics, but we are opening it to the public, too. The format of the competition is three problems over five hours, with each solution consisting of a source file in C, C++, Java or Haskell, which is compiled and executed against a set of test data on our servers. The contest will be held tomorrow (Saturday 15th) from 13:00 to 18:00 South African Standard Time (GMT+2). We will hold a discussion afterwards in the #saco channel on the FreeNode IRC network. Email queries to online-contest(a)olympiad.cs.uct.ac.za You can find out more and register at http://olympiad.cs.uct.ac.za/contest.html I apologise for the late notice: we have been affected by a countrywide power shortage, with our server going down every couple of days for the past week or two. Hoping to see you there, Max Rabkin

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Mathematics of Program Construction 2008: Call for papers
by Jeremy Gibbons 14 Dec '07

14 Dec '07

I don't believe that has been sent to the Haskell mailing list before, but apologies if it has. This CFP has been around since October; the submission deadline is 14th Jan (abstracts). Jeremy * CALL FOR PAPERS 9th International Conference on Mathematics of Program Construction (MPC'08) Marseille (Luminy), France, July 15-18th 2008 http://mpc08.lri.fr BACKGROUND The biennial MPC conferences aim to promote the development of mathematical principles and techniques that are demonstrably practical and effective in the process of constructing computer programs. Topics of interest range from algorithmics to support for program construction in programming languages and systems. The previous conferences were held in Twente, The Netherlands (1989), Oxford, UK (1992), Kloster Irsee, Germany (1995), Marstrand, Sweden (1998), Ponte de Lima, Portugal (2000), Dagstuhl, Germany (2002), Stirling, UK (2004, colocated with AMAST '04) and Kuressaare, Estonia (2006, colocated with AMAST '06). The 2008 conference will be held in Marseille, France at the International Center for Mathematical Meetings (http://http://www.cirm.univ-mrs.fr/web.ang) INVITED SPEAKERS To be announced. IMPORTANT DATES * Submission of abstracts: 14 January 2008 * Submission of full papers: 21 January 2008 * Notification of authors: 10 March 2008 * Camera-ready version: 10 April 2008 TOPICS Papers are solicited on mathematical methods and tools put to use in program construction. Topics of interest range from algorithmics to support for program construction in programming languages and systems. Some typical areas are type systems, program analysis and transformation, programming-language semantics, program logics. Theoretical contributions are welcome provided their relevance for program construction is clear. Reports on applications are welcome provided their mathematical basis is evident. SUBMISSION Submission is in two stages. Abstracts (plain text) must be submitted by 14 January 2008. Full papers (pdf) adhering to the llncs style must be submitted by 21 January 2008. There is no official page limit, but authors should strive for brevity. The web-based submission system will open in early December 2007. Papers must report previously unpublished work and not be submitted concurrently to another conference with refereed proceedings. Accepted papers must be presented at the conference by one of the authors. The proceedings of MPC'08 will be published in the Lecture Notes in Computer Science series of Springer-Verlag. After the conference, the authors of the best papers will be invited to submit revised versions to a special issue of the Science of Computer Programming journal of Elsevier. PROGRAMME COMMITTEE Christine Paulin-Mohring INRIA-Université Paris-Sud, France (chair) Philippe Audebaud Ecole Normale Supérieure Lyon, France (co-chair) Ralph-Johan Back Abo Akademi University, Finland Eerke Boiten University of Kent, UK Venanzio Capretta University of Nijmegen, Netherlands Sharon Curtis Oxford Brookes University, UK Jules Desharnais Université Laval, Québec, Canada Peter Dybjer Chalmers University of Technology, Sweden Jeremy Gibbons University of Oxford, UK Lindsay Groves Victoria University of Wellington, New Zealand Ian Hayes University of Queensland, Australia Eric Hehner University of Toronto, Canada Johan Jeuring Utrecht University, Netherlands Dexter Kozen Cornell University, USA Christian Lengauer Universität Passau, Germany Lambert Meertens University of Utrecht, Netherlands Bernhard Möller Universität Augsburg, Germany Carroll Morgan University of New South Wales, Australia Shin-Cheng Mu Academia Sinica, Taiwan Jose Nuno Oliveira Universidade do Minho, Portugal Tim Sheard Portland State University, USA Tarmo Uustalu Institute of Cybernetics Tallin, Estonia VENUE The conference will be held in Marseille, the second largest city in France next to Paris. Its port is the most important in France, and opens the city to the world through the Mediterranean Sea. MPC'08 will be hosted by the International Center for Mathematical Meetings. The center is located inside the Campus of Luminy Faculty. It is close to the "Calanques", an astounding wild coastline composed of creeks stretching from Marseille to Cassis. LOCAL ORGANIZERS MPC 2008 is organized with the support of INRIA. The local organizers are Philippe Audebaud and Christine Paulin-Mohring. Enquiries regarding the programme (submission etc.) should be addressed to mpc08(at)lri.fr

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Genuine shift/reset in Haskell98
by oleg＠okmij.org 12 Dec '07

12 Dec '07

This message announces the Haskell98 implementation of Asai and Kameyama's polymorphic delimited continuations, with effect typing, full soundness (well-typed terms don't give any run-time exceptions), answer-type modification and polymorphism. Thanks to parameterized monads the implementation is the straightforward translation of the rules of the calculus. Parameterized monads seem to have proven their claim for syntactic sugar. http://okmij.org/ftp/Haskell/ShiftResetGenuine.hs Delimited control operators shift/reset are, fortunately, becoming popular. Alas, all widely available implementations suffer deficiencies: for example, the type system does not prevent attempts to execute shift outside the dynamic scope of reset, which leads to a run-time error. Furthermore, the implementations do not permit modifications of the answer-type, and so make impossible many elegant applications of shift/reset such as fully typed sprintf. In particular, shift id (or, shift return, in the monadic form), so often used in linguistics, are not typeable in any widely available implementation of delimited continuations. Related to the first issue, implemented calculi of delimited continuations are not strongly normalizing. That fact has been known for some time; it has been shown recently that the calculus of multi-prompt delimited continuations -- the DC calculus of the DDBinding paper, implemented in the DelimCC Haskell library -- expresses the fix-point combinator and emulates general recursive types, and so is, in fact, Turing complete. http://okmij.org/ftp/Computation/Continuations.html#delimcc-rectype Back in 1989 Danvy and Filinski recognized that ensuring strong type soundness (aka, control decency: no naked shift) requires a type-and-effect system. They proposed a (monomorphically typed) type system with answer-type modifications. Alas, it has not been implemented in any widely available language (or even formally published for that matter: the only source is the DIKU Technical Report). In the recent APLAS 2007 paper, Asai and Kameyama have developed a polymorphically typed calculus of delimited continuations with answer type modifications. They have proven greatly desirable properties of their calculus: strong type soundness, principal types, the existence of a type inference algorithm, preservation of types and equality through CPS translation, confluence, strong normalization for the subcalculus without fix. http://logic.cs.tsukuba.ac.jp/~kam/paper/aplas07.pdf http://pllab.is.ocha.ac.jp/~asai/papers/aplas07slide.pdf The particularly elegant application of their calculus is typed sprintf: sprintf format_expression arg1 arg2 .... The type system ensures that the number and the types of format specifiers in format_expression agree with the number and the types of arg1, etc. Provided control operators supporting both answer-type modification and polymorphism, sprintf is expressible as a regular function (and a very simple one: the entire solution takes only four lines). This problem is described in more detail in http://pllab.is.ocha.ac.jp/~asai/papers/tr07-1.ps.gz Alas, Asai and Kameyama's calculus has only been implemented in a privately modified version of mini-ML. This link at the beginning points to the complete, short implementation, including the sprintf example. The implementation is in Haskell98; contrary to the popular belief, the latter is still a capable language. Thus the genuine control operators have become practically available for the first time. We rely on parameterized monads, Robert Atkey, Parameterised Notions of Computation, Msfp2006 http://homepages.inf.ed.ac.uk/ratkey/param-notions.pdf see also http://www.haskell.org/pipermail/haskell/2006-December/018917.html To be more precise, we represent the the effectful expression e, whose type is characterized by the judgment Gamma; a |- e:tau; b as a parameterized monad C a b tau. We represent an effectful function type sigma/a -> tau/b of the calculus as an arrow type sigma -> C a b tau. We greatly benefit from two lucky circumstances. First, the rule 'app' of Asai and Kameyama (Fig 3 of their paper) turns out to be expressible as a composition of two binds in the parameterized monad. Second, the existing type inference of Haskell matches unbelievably well with the let-rule of Asai and Kameyama: the type of only pure expressions can be generalized. Indeed, impure expressions have the type C a b tau and can be meaningfully used only with bind, which forces the monomorphic treatment. Pure expressions such as functions, numbers, etc. can be applied without the assistance of bind; luckily, Haskell generalizes the type in their definitions automatically. The rest of the implementation is the trivial transcription of the types in Fig 3 and the derivation of the corresponding proof terms. The sprintf test has the following form (slightly less elegant compared to ML) stest1 = run $ sprintf (ret "Hello world") -- "Hello world" stest2 = run $ sprintf (ret "Hello " ^ fmt str ^ ret "!") $$ "world" -- "Hello world!" stest3 = run $ sprintf (ret "The value of " ^ fmt str ^ ret " is " ^ fmt int) $$ "x" $$ 3 -- "The value of x is 3" Obviously, the type of sprintf (format_expression) depends on the number and the type of format specifiers (fmt) in the format expression. The function sprintf is a simple ordinary function: sprintf p = reset p

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