August 2005 - Haskell

ANNOUNCE: ghc-src version 0.2.0
by Lemmih 30 Aug '05

30 Aug '05

ghc-src 0.2.0 has been released. ghc-src is a Haskell parser with full support for every GHC extension. It is a refactored version of the Haskell parser used internally by GHC and is meant as a replacement for haskell-src-exts, although it might have other uses. The package is cabalized and lives under Langauge.Haskell.GHC.* in the module hierarchy. Darcs repo: http://scannedinavian.org/~lemmih/ghc-src/ -- Friendly, Lemmih

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Who brought the monad to us?
by Wolfgang Jeltsch 30 Aug '05

30 Aug '05

Hello, is it right to say that Philip Wadler was the one who invented monadic I/O or were there others who did so together with Wadler? I need this for my thesis. :-) Best wishes, Wolfgang

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How to use STArray?
by Benjamin Franksen 29 Aug '05

29 Aug '05

Hmmm, no answer on cafe, maybe someone here with a good idea? ---------- Forwarded Message ---------- On Thursday 25 August 2005 19:58, Udo Stenzel wrote: > [...] you'll need a type signature somewhere to help ghc resolve > the overloading of newArray and readArray, which is surprisingly > tricky due to the "s" that must not escape. This works: > > compute :: Int -> Int > compute n = runST ( do > arr <- newArray (-1, 1) n :: ST s (STArray s Int Int) > readArray arr 1 > ) Hello, I am fighting with a similar problem. I want to use STUArray but without committing to a fixed element type. For instance (this is not my real problem, but it's similar and easier to motivate), here is a function that appends two UArrays: A little helper first > copy :: (MArray a e m, IArray b e) => > a Int e -> Int -> b Int e -> Int -> Int -> m () > copy dest destix src srcix cnt > > | cnt <= 0 = return () > | otherwise = do > > writeArray dest destix (src ! srcix) > copy dest (destix+1) src (srcix+1) (cnt-1) and here is the append function > append :: UArray Int e -> UArray Int e -> Int -> UArray Int e > append x y low = runSTUArray (do > z <- newArray_ (low,low+len x+len y) > copy z low x (first x) (len x) > copy z (low+len x) y (first y) (len y) > return z) > where > len = rangeSize . bounds > first = fst . bounds Of course this can't work, because 'copy' needs the MArray and IArray contexts: No instance for (MArray (STUArray s) e (ST s)) arising from use of `copy' at Problem.lhs:31:7-10 [...] No instance for (IArray UArray e) arising from use of `copy' at Problem.lhs:31:7-10 [...] But now, when I add > append :: (IArray UArray e, MArray (STUArray s) e (ST s)) => ... I still get the same error message regarding the MArray constraint: No instance for (MArray (STUArray s) e (ST s)) arising from use of `copy' at Problem.lhs:31:7-10 What am I missing? That is, how and where do I have to specify the constraint? Ben

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2nd CFP: M4M-4 "Methods for Modalities"; Berlin, Dec. 1-2, 2005
by Holger Schlingloff 29 Aug '05

29 Aug '05

Apologies if you receive this CFP more than once. Please note that the submission deadline has been extended to Sep. 15th! *************************************************************************** The workshop "Methods for Modalities" (M4M) aims to bring together researchers interested in developing algorithms, verification methods and tools based on modal logics. Here the term "modal logics" is conceived broadly, including description logic, guarded fragments, conditional logic, temporal and hybrid logic, etc. To stimulate interaction and transfer of expertise, M4M will feature a number of invited talks by leading scientists, research presentations aimed at highlighting new developments, and submissions of system demonstrations. We strongly encourage young researchers and students to submit papers and posters, especially for experimental and prototypical software tools which are related to modal logics. Invited speakers: François Laroussinie, ENS Cachan and CNRS Martin Lange, Ludwig-Maximilians-Universität Wim Martens, Hasselt University Boris Motik, Universität Karlsruhe Boris Konev, University of Liverpool Uwe Scheffler, Humboldt Universität Regular papers should not exceed the length of 12 pages; short papers are up to six pages of length, and posters and tools can be presented on two pages of text. Proceedings will appear online and as a Humboldt university report. Depending on the submissions, papers may be selected to appear in a special issue of an appropriate journal. Submission is by internet or email. You can (preferrably) upload your PostScript or PDF contribution to the address http://www.easychair.org/M4M-4/submit/ or (alternatively) send it to m4m-4(a)first.fraunhofer.de. The workshop will take place in Berlin - Adlershof, Germany, which is one of the worlds largest science and technology areas, comprising twelve research institutes, six faculties of the Humboldt University of Berlin, and more than 370 high tech companies. It is hosted by FIRST, the Fraunhofer Institute of Computer Architecture and Software Technology, in collaboration with the computer science institute of Humboldt University. For more information and registration information, see the M4M homepage at http://m4m.loria.fr/ Deadline for submissions: September 15th, 2005 (extended!) Notification: October 17, 2005 Camera ready versions: November 8, 2005 Workshop dates: December 1-2, 2005 The program committee for M4M consists of Holger Schlingloff, Humboldt University / FIRST (local organizations); Carlos Areces, INRIA Lorraine; Patrick Blackburn, INRIA Lorraine; Torben Brauner, Roskilde University; Stephane Demri, ENS de Cachan; Enrico Franconi, Free University of Bolzano; Rajeev Gore, Australian National University; Ian Horrocks, University of Manchester; Joost-Pieter Katoen, RWTH Aachen; Maarten de Rijke, University of Amsterdam; Renate Schmidt, University of Manchester; and Frank Wolter, University of Liverpool.

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Parsing binary data
by Joel Reymont 28 Aug '05

28 Aug '05

Folks, I'm trying to parse chunks of binary data that arrive through a socket. There's a defined format of these chunks where the first 4 bytes are an id, then could come a Pascal (size first) string, then some more data. I'm trying to figure out how to read and write Haskell data in this format and using a socket. Would someone have examples? Thanks, Joel -- http://wagerlabs.com/tech

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UPDATE: NWPT05 Annoucenment
by jespera＠diku.dk 26 Aug '05

26 Aug '05

ANNOUNCEMENT AND CALL FOR PAPERS FOR NWPT05 =========================================== The 17th Nordic Workshop on Programming Theory http://www.diku.dk/NWPT05/ The NWPT series of annual workshops is a forum bringing together programming theorists from the Nordic and Baltic countries (but also elsewhere). This year the workshop will be held in COPENHAGEN. SCOPE Typical topics of the workshop include (but are not limited to) o Semantics of programs o Programming logics o Program verification o Formal specification of programs o Program synthesis o Program transformation and program refinement o Real-Time and hybrid systems o Modeling of concurrency o Programming methods o Tools for program construction and verification INVITED SPEAKERS o Patricia Johann, Rutgers University, USA o Carsten Schuermann, (Yale, now: IT University of Copenhagen) o Stephen Alstrup, Octoshape o Peter Sestoft, KVL, IT University of Copenhagen o Olivier Danvy, BRICS, DIKU SUBMISSIONS Authors wishing to give a talk at the workshop are requested to submit an abstract of 1-3 pages (ps or pdf, printable on A4 paper) to nwpt05(at)diku.dk by 19th September 2005. Submission of work submitted for formal publication elsewhere and work in progress is permitted. The abstracts of the accepted contributions will be available at the workshop. After the workshop, selected papers will be published in a special issue of "Nordic Journal of Computing". IMPORTANT DATES (TENTATIVE) 19 September: Submission of abstracts 5 October: Notification of acceptance 12 October: Registration (see below) 19-21 October: WORKSHOP REGISTRATION To register for the workshop, complete the registration form on the webpage of the workshop (www.diku.dk/NWPT05/) The workshop fee includes registration, participants proceedings, coffee, lunches, reception, and a banquet. PROGRAMME COMMITTEE o Neil D. Jones (chair), Univ. of Copenhagen, Denmark o Michael R. Hansen, Techn. U. of Denmark, Denmark o Magne Haveraaen, Univ. of Bergen, Norway o Hannu-Matti Jarvinen, Tampere Univ. of Tech., Finland o Kim G. Larsen, Aalborg Univ., Denmark o Bengt Nordstrom, Univ. of Gothen, Chalmers Univ. of Tech., Sweden o Olaf Owe, University of Oslo, Norway o Kaisa Sere, Abo Akademi University, Finland o Tarmo Uustalu, Inst. of Cubernetics, Estonia o Juri Vain, Tallinn Technical University, Estonia o Wang Yi, Uppsala Univ., Sw ORGANIZING COMMITTEE o Karin Outzen (secretary) o Jesper Andersen (graduate student) o Andrzej Filinski o Jakob Grue Simonsen o Neil Jones More (and current) information can be found at the workshop homepage: http://www.diku.dk/NWPT05

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mini-Announce: update to Happy-GLR templates
by P.C.Callaghan 26 Aug '05

26 Aug '05

Hello, I've recently checked in modified template code for the GLR mode of Happy. It handles densely ambiguous grammars a lot better, although may be slower on more reasonable grammars, particularly if empty productions are heavily used (eg for gap rules in biological sequence grammars). For example, it can parse "E -> E + E | i" on sentences with 201 tokens in a small number of seconds; the previous version could not handle more than 41 in reasonable time. You can get the code from CVS, or download the files via the following: http://www.dur.ac.uk/p.c.callaghan/happy-glr/new-templates.tgz http://www.dur.ac.uk/p.c.callaghan/happy-glr/new-templates.zip There's still plenty of room for further speed improvements. Contact me if interested. Further information can be found at: http://www.dur.ac.uk/p.c.callaghan/happy-glr Paul -------------------------------------------------------------------------- Dr Paul Callaghan (Lecturer) Email: P.C.Callaghan(a)durham.ac.uk Dept of Computer Science, Durham http://www.dur.ac.uk/p.c.callaghan

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ANNOUNCEMENT: HAskell Server Pages version 0.3.0
by Lemmih 25 Aug '05

25 Aug '05

== HAskell Server Pages == HASP is an experimental framework for combining the flexibility of Haskell with the popularity/necessity of web-pages. HASP offers you an embedded XML syntax, without you having to dispense with any of the Glasgow Haskell extensions we hold dear. By using the FastCGI library, HASP has obtained Independence of server type while keeping performance at a max. HASP supports dynamic loading of Haskell code, sessions, persistent values of arbitrary types, POST data and file uploads, and thus provides a sound foundation for the creation of high level programming models for writing dynamic web-pages. A few features have yet to see the light of day: Session storage should be at the users discretion, and supported reconfiguration of HASP at run-time are possible improvements. While HASP isn't in it self a high level programming model for designing dynamic web-pages, it does provide a sound foundation for the creation of such. HASP: darcs get http://scannedinavian.org/~lemmih/hsp FastCgi: http://fastcgi.com/ I would appreciate any feedback. -- Friendly, Lemmih PS: I owe great thanks to Niklas Broberg for his excellent work on HSP. In truth, the idea of combining XML and Haskell I have through him, and I also adapted much of his code.

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APLAS 2005 -- Call For Posters
by Hongseok Yang 25 Aug '05

25 Aug '05

[apologies for cross-posting] CALL FOR POSTER PRESENTATIONS The Third ASIAN Symposium on Programming Languages and Systems (APLAS 2005) November 3-5 2005 Tsukuba, Japan Deadline for Abstract Submission: 16 September, 2005 http://ropas.snu.ac.kr/2005/aplas/openconfp/openconf.php APLAS 2005 will include a poster session during the first day of the conference (November 3). The poster session aims to give students and professionals an opportunity to present technical materials to the research community, and to get technical advice from other researchers in the field. SCOPE: Poster contributions are sought in all areas of programming languages and systems, including the following topics: - semantics, logics, foundational theory - type systems, language design - program analysis, optimization, transformation - software security, safety, verification - compiler systems, interpreters, abstract machines - domain-specific languages and systems - programming tools and environments for embedded and mobile code FORMAT: In the poster session, each participant will be provided with a space for posting their diagrams and short descriptions of their research. The space will usually be for approximately an A1 sized paper (594x841mm). If the participant needs a bigger space, he/she should contact the poster chair, Hongseok Yang (hyang(a)ropas.snu.ac.kr) Contact with your audience happens through casual conversation. Count on only a reasonable attention span when describing your work. Over five minutes is usually overdoing it. Prepare a list of questions that you would like help getting answered. REGISTRATION INFORMATION: Presenters should submit 1-2 pages abstract paper in PDF or Postscript format that summarize the poster topic via the online form (at http://ropas.snu.ac.kr/2005/aplas/openconfp/openconf.php) by 16 September, 2005. The program of the poster session will be announced by 07 October, 2005. We hope to accommodate everyone wishing to present, but may restrict presentations (based on relevance and interest to the community) due to space restrictions. Also, we may need to cancel the session if there is too little interest. In addition, participants are requested to read other participants' abstracts to provide feedback before the conference. Comments on what points they are interested in the other participants abstracts, what should be emphasized, what can be omitted, etc., should improve the quality of the posters. IMPORTANT DATES: - 1-2 pages abstract submission 16 September, 2005 - announcement of poster session program 7 October, 2005 - poster session 3 November, 2005 CONTACT INFORMATION: For additional information, clarifications, questions, or special requirements, please contact the APLAS 2005 Poster Chair, Hongseok Yang (hyang(a)ropas.snu.ac.kr)

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ANNOUNCE: Haddock version 0.7
by Simon Marlow 24 Aug '05

24 Aug '05

Haddock 0.7 is released, get it from here: http://www.haskell.org/haddock/ Haddock is a tool for generating documentation for Haskell libraries. This new version has already been in use for some time generating the documentation for GHC's libraries: http://www.haskell.org/ghc/docs/latest/html/libraries/index.html Here's the change list for version 0.7: * Changes in the way Haddock decides where to direct hyperlinks. Each entity is now assigned a single "home" module, and all hyperlinks are directed to that module. See the docs ("Hyperlinking and re-exported entities") for details. * New options --ignore-all-exports, --hide * New option --use-package for creating documentation that hyperlinks to the HTML documentation for existing packages on your system. It works by querying ghc-pkg for the location of the Haddock interface and HTML for the given package. * Parts of the HTML documentation, notably lists of instances, are now "collapsible" with a +/- button. Also, the contents page is now in the form of tree in which subtrees can be collapsed. * Support for Microsoft DevHelp and HtmlHelp 2.0 formats. * Support for a short description for each module for the contents page. * Compiles with GHC 6.4+ * Various bugfixes Thanks to everyone who contributed to this version. The TODO list grows long, however - more help is always welcome! Cheers, Simon

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