January 2003 - Haskell

Evaluation Question
by Matthew Donadio 11 Jan '03

11 Jan '03

Hi all, I have a question about lazy evaluation. In the following function: > nco :: RealFloat a => a -> [ Complex a ] > nco wn = 1 : map ((*) (cis wn)) (nco wn) will the sin and cos associated with cis be evaluated once, or for each call? Thanks. -- Matthew Donadio (m.p.donadio(a)ieee.org)

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Re: Web Application Development
by Dominic Steinitz 11 Jan '03

11 Jan '03

I have summarised the responses I have received and cross posted this to Haskell-Cafe in case anyone wishes to carry on the conversation. > In a moment of weakness, I offered to help a friend develop a website. It's > a simple database application which carries out very little calculation and > then displays the results via HTML. > > The original code was in PHP and MySQL so rather than re-invent the wheel I > > So my question is: what should I do to re-write this in Haskell? > 1. SQL 1.a. MySQL 1.a.i Use MySQL-HS which requires the use of H/Direct. Available via www.haskell.org. 1.a.ii Use http://cvs.sourceforge.net/cgi-bin/viewcvs.cgi/hbase/Source/Foreign/. This is pre-alpha. 1.b Oracle 1.b.i Use C2HS and libsqlora8 (a simple C library for interfacing to Oracle http://www.poitschke.de/libsqlora8/) There is no publicly available code. 1.c Database Independent 1.c.i Use the DBI model as found in Perl and the libpq binding as listed on Haskell.org (http://www.astercity.net/~khaliff/haskell/dbi/dbi.tgz) This currently has a PostgreSQL binding but is not listed on SourceForge. 1.c.ii Use the code at http://sourceforge.net/projects/htoolkit/. This is planning (that is pre pre-alpha). There appear to be bindings for MySQL, ODBC and PostgreSQL. 2. HTML I have tried out Wash/CGI and this seems satisfactory for my purposes at the moment. Many thanks to everyone who replied, Dominic.

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RTA'03: last call for papers
by Femke van Raamsdonk 10 Jan '03

10 Jan '03

*********************************** * * * RTA'03 LAST CALL FOR PAPERS * * * *********************************** http://www.dsic.upv.es/~rdp03/rta The 14th Int. Conf. on Rewriting Techniques and Applications (RTA'03) will be part of the Federated Conf. on Rewriting, Deduction and Programming (RDP'03). IMPORTANT DATES: Jan 15 2003: Deadline electronic submission of title+short abstract Jan 22 2003: Deadline electronic submission of papers Mar 15 2003: Notification of acceptance of papers Apr 7 2003: Deadline for final versions of accepted papers Jun 9-11 '03: Conference. RTA is the major forum for the presentation of research on all aspects of rewriting. Typical areas of interest include (but are not limited to): * APPLICATIONS: case studies; (rule-based) programming; symbolic and algebraic computation; theorem proving; system synthesis and verification; proof checking. * FOUNDATIONS: matching and unification; narrowing; completion techniques; strategies; constraint solving; explicit substitutions. * FRAMEWORKS: string, term, and graph rewriting; lambda-calculus and higher-order rewriting; proof nets; constrained rewriting/deduction; categorical and infinitary rewriting. * IMPLEMENTATION: compilation techniques; parallel execution; rewriting tools. * SEMANTICS: equational logic; rewriting logic. INVITED TALKS will be given at RTA'03 by: * David McAllester Toyota Technological Institute at Chicago Joint invited speaker with TLCA * Jean-Louis Giavitto Universit� d'Evry, France * Pat Lincoln SRI International BEST PAPER AWARDS: A 1000 Euro award wil be given to the best paper or papers as decided by the PC. The award may also totally or partially go to the best paper with a student as main author, according to the submission letter. RTA'03 PROGRAM COMMITEE: * Harald Ganzinger (Max-Planck-Institut) * Claude Kirchner (Nancy) * Salvador Lucas (Valencia) * Chris Lynch (Clarkson) * Jos� Meseguer (Urbana) * Robert Nieuwenhuis (Barcelona, Chair) * Tobias Nipkow (Munich) * Vincent van Oostrom (Utrecht) * Christine Paulin (Paris-sud) * Frank Pfenning (Carnegie Mellon) * Mario Rodr�guez-Artalejo (Madrid) * Sophie Tison (Lille) * Ashish Tiwari (SRI) * Andrei Voronkov (Manchester) * Hantao Zhang (Iowa) RTA'03 SUBMISSIONS: Submissions must be original and not submitted for publication elsewhere. Submission categories include regular research papers and system descriptions. Also problem sets and submissions decribing interesting applications of rewriting techniques will be very welcome. As usual, accepted papers will appear in the Springer-Verlag Lecture Notes in Computer Science series. See the RDP'03 web page <http://www.dsic.upv.es/~rdp03/> for details. For further questions please contact the program chair: RTA'03 PROGRAM CHAIR: Robert Nieuwenhuis Technical University of Catalonia Jordi Girona 1, E-08034 Barcelona, Spain roberto(a)lsi.upc.es

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laziness in IO
by Amanda Clare 09 Jan '03

09 Jan '03

How can I recursively collect a list of things while in the IO monad, and return the list lazily as it's constructed rather than waiting until they've all been collected? Perhaps an example will make things clearer: main = do xs <- getStrings putStrLn (head xs) getStrings = do x <- getLine if x == "stop" then return [] else do xs <- getStrings return (x:xs) How can I make getStrings lazy? main should be able to terminate immediately after I've entered just one line. Amanda ps: This is a fake example, I'm really trying to lazily retrieve answers fetched from an Oracle SQL query.

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Call for Workshops at FM03
by mailinglist-admin＠fmeurope.org 09 Jan '03

09 Jan '03

Call for Satellite Workshops FM 2003 - The 12th International FME Symposium Pisa, Italy - September 8-14, 2003 We kindly invite you to consider organising a Satellite Workshop of the FM 2003 Symposium (http://fme03.isti.cnr.it/) Workshops are welcome on any aspect of the theory and application of Formal Methods, from language-specific issues to model integration, from tool experience to new challenging application domains. FM 2003 and associated workshops shall take place in the scientific and technological complex recently established at Pisa by the Italian National Research Council (http://www.area.pi.cnr.it/indexe.html) which lends itself as an ideal location for conferences and workshops, in terms of spaces, facilities, and vicinity to major tourist attractions. Workshop formats - Two-day workshops: on Sept. 8-9 (Monday-Tuesday) 2003. - One-day workshops: on Sept 13 (Saturday) 2003. The following information should be provided with the proposals - Workshop title and brief description of the scope and goal - Motivation of the relevance to the FM community - Organizing commitee and potential invited speakers - Format of the workshop, duration and refereeing procedure, if applicable - Expected number of participants FM 2003 organizers offer - Links between Conference and Workshop web pages. - Management of registrations and hotel reservations. - Room (up to 80 seats) and equipment (projectors, whiteboards etc.). - One lunch and two coffee breaks per day. Workshop proposers take care of - Workshop pubblicity - Call for papers - Paper management - Proceedings duplication (paper and/or CD) and distribution. Important dates Proposal submission: March 7, 2003 Acceptance notification: March 20, 2003 Workshop dates: Sept. 8, 9, 13, 2003 Contact Tommaso Bolognesi (FM 2003 Workshop chair) - t.bolognesi(a)iei.pi.cnr.it -- ======================================================================== Tommaso Bolognesi phone: +39-050-315.2797 CNR - ISTI fax: +39-050-315.2810 Via Moruzzi 1 e-mail: t.bolognesi(a)iei.pi.cnr.it 56124 Pisa web: www.iei.pi.cnr.it/People/Bolognesi.html Italia ======================================================================== in-girum-imus-nocte-et-consumimur-ignI (iveL OmirP) <--- ========================================================================

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Debugging Arrays
by Matthew Donadio 09 Jan '03

09 Jan '03

Hi all, I am having a tough time debugging an array problem, and I was wondering if anyone had some pointers. I am working on a complicated function that relies on a few mutually recursive arrays (AR parameter estimation using Burg's Method). I am getting a runtime error, index: Index out of range, when I test out the function. For the life of me, I cannot figure out where the error is. One complication is that not all of the arrays elements are defined for the index bounds. I have tried several simplifications to isolate the arrays, but when I simplify too far, I run into type problems. Is there an easy way to trace execution? Does anyone have any advice on how to go about debugging this? I am using Hugs 98, November 2002 if it matters. Thanks. -- Matthew Donadio (m.p.donadio(a)ieee.org)

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Re: Field labels must be globally unique?
by Tom Pledger 08 Jan '03

08 Jan '03

A third way is to put each datatype declaration in a separate module and use qualified imports.

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EACL2003: Submission for workshop papers extended till January 13 2003!!!!!!!
by Steven.Krauwer＠elsnet.org 07 Jan '03

07 Jan '03

EACL 2003 in Budapest, April 12-17, 2003 Workshop Programme and Very Last Call for Workshop Papers [ EXTENDED DEADLINE FOR ALL WORKSHOPS IS MONDAY, JANUARY 13 2003 ] Important dates for all workshops: ---------------------------------- Submission deadline: Jan 13, 2003 (extended) Notification: Jan 28, 2003 Deadline for final papers: Feb 13, 2003 Workshop dates: Apr 13/14, 2003 Conference dates: Apr 12-17, 2003 Important URLs: --------------- Main conference: http://www.conferences.hu/EACL03/ Workshops: http://www.elsnet.org/workshops Workshop overview: ------------------ Workshop w01: "MT and other language technology tools; Improving MT through other language technology tools; Resources and tools for building MT" URL: not available Organizer(s): Bente Maegaard Email: bente(a)cst.dk CfP: http://www.elsnet.org/workshops/w01.doc Date: April 13, 2003 ___________________________________________________________________ Workshop w02: "9th European Workshop on Natural Language Generation" URL: http://www.ags.uni-sb.de/~horacek/EACL-EWNLG03.html Organizer(s): Ehud Reiter Email: ereiter(a)csd.abdn.ac.uk CfP: http://www.elsnet.org/workshops/w02.txt Date: April 13+14, 2003 ___________________________________________________________________ Workshop w03: "4th International Workshop on Linguistically Interpreted Corpora (LINC-03)" URL: http://www.coli.uni-sb.de/linc03 Organizer(s): Silvia Hansen Email: hansen(a)CoLi.Uni-SB.DE CfP: http://www.elsnet.org/workshops/w03.txt Date: April 14, 2003 ___________________________________________________________________ Workshop w04: "Language Modeling for Text Entry Methods" URL: http://www.uni-koblenz.de/~compling/eaclws2003/ Organizer(s): Michael Kuhn Email: kuehn(a)uni-koblenz.de CfP: http://www.elsnet.org/workshops/w04.txt Date: April 13, 2003 ___________________________________________________________________ Workshop w05: "The Computational Treatment of Anaphora" URL: http://www.clt.mq.edu.au/eacl03ana.html Organizer(s): Rob Dale Email: rdale(a)ics.mq.edu.au CfP: http://www.elsnet.org/workshops/w05.txt Date: April 14, 2003 ___________________________________________________________________ Workshop w06: "Dialogue Systems: interaction, adaptation and styles of management" URL: http://www.dcs.shef.ac.uk/~roberta/eacl-w06.html Organizer(s): Kristiina Jokinen and Roberta Catizone Email: kjokinen@uiah.fi,R.Catizone@dcs.shef.ac.uk CfP: http://www.elsnet.org/workshops/w06.txt Date: April 13+14, 2003 ___________________________________________________________________ Workshop w07: "Evaluation Initiatives in Natural Language Processing: are evaluation methods, metrics and resources reusable?" URL: http://www.dcs.shef.ac.uk/~katerina/EACL03-eval Organizer(s): Katerina Pastra Email: e.pastra(a)dcs.shef.ac.uk CfP: http://www.elsnet.org/workshops/w07.txt Date: April 13, 2003 ___________________________________________________________________ Workshop w08: "Computational Linguistics for South Asian Languages -- Expanding Synergies with Europe" URL: not available Organizer(s): Durgesh Rao and Pat Hall Email: durgesh@saathi.ncst.ernet.in,p.a.v.hall@open.ac.uk CfP: http://www.elsnet.org/workshops/w08.txt Date: April 14, 2003 ___________________________________________________________________ Workshop w09: "Workshop on Finite State Methods in Natural Language Processing" URL: http://www-igm.univ-mlv.fr/~laporte/fsw-cfp.htm Organizer(s): Eric Laporte and Ken Beesley Email: eric.laporte@univ-mlv.fr,Ken.Beesley@xrce.xerox.com CfP: http://www.elsnet.org/workshops/w09.txt Date: April 13+14, 2003 ___________________________________________________________________ Workshop w10: "Language Technology and the Semantic Web: 3rd Workshop on NLP and XML (NLPXML-2003)" URL: http://www.cs.vassar.edu/~ide/events/NLPXML3.html Organizer(s): Nancy Ide and Graham Wilcock Email: ide@cs.vassar.edu,graham.wilcock@helsinki.fi CfP: http://www.elsnet.org/workshops/w10.txt Date: April 14, 2003 ___________________________________________________________________ Workshop w11: "Natural Language Processing (NLP) for Question-Answering" URL: not available Organizer(s): Bonnie Webber and Maarten de Rijke Email: bonnie@inf.ed.ac.uk,mdr@science.uva.nl CfP: http://www.elsnet.org/workshops/w11.txt Date: April 13, 2003 ___________________________________________________________________ Workshop w12: "Morphological Processing of Slavic Languages" URL: http://nl.ijs.si/mpsl03/ Organizer(s): Tomaz Erjavec and Dusko Vitas Email: Tomaz.Erjavec@ijs.si,vitas@matf.bg.ac.yu CfP: http://www.elsnet.org/workshops/w12.txt Date: April 13, 2003 ___________________________________________________________________ Contact info: - for the workshops in general: steven.krauwer(a)elsnet.org - for individual workshops: workshop organizers - for the main conference: kindl(a)sztaki.hu _______________________________________________________________

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CFP: Workshop on Model Checking and Artificial Intelligence (MoChArt-03)
by Massimo Benerecetti 07 Jan '03

07 Jan '03

APOLOGIES IF YOU RECEIVE MORE THAN ONE COPY OF THIS MESSAGE. ===================================================================== CALL FOR PAPERS & PARTICIPATION *************************************** SECOND WORKSHOP ON MODEL CHECKING AND ARTIFICIAL INTELLIGENCE (MoChArt-03) August 10, 2003, Acapulco, Mexico IJCAI-03 Workshop Program ===================================================================== Model checking (MC) is the name given to the process of determining whether or not a formula of some logic is satisfied by a model for the logic. Model checking is limited by its exponential complexity with respect to the size of the system being verified. Nevertheless, MC procedures for many classes of models and logics of interest have been efficiently automated and successfully applied to a broad range of real-size applications in the last decade. These recent advances have lead to a growth of interest in the use of the technology in Artificial Intelligence (AI). In the meantime, state space exploration is a central aspect of AI, and the AI community has a long and impressive line of research in developing and improving search algorithms over very large state spaces under a broad range of assumptions. MC researchers are showing a growing interest in this vast body of knowledge, as a way to mitigate the state-space explosion problem. Under a slightly different perspective there is growing interest in the use of model checking techniques for verifying and validating AI applications (as opposed to inside these applications themselves). This is becoming a critical issue, as AI techniques are increasingly considered for safety-critical applications such as space missions. AI software typically features unconventional architectures and requirements that ask for specific verification solutions. These solutions will only emerge from a sustained dialogue between the AI and V&V communities, through forums such as this one. The purpose of the Second MoChArt workshop is therefore to bring together researchers with an interest in both MC and AI. The goals are to tease out common themes and differences, identify common problems and their solutions, share experiences with the applicability of techniques from one field to problems from the other, and to identify the key issues to be addressed in increasing the convergence between MC and AI. The workshop will welcome submissions on all ideas, research, experiments and tools that relate to both MC and AI fields. Topics of interest include: - Foundations - Comparisons between MC and AI problems, approaches and algorithms. - Model checking for combined modal/temporal logics - Model checking for logics of common sense reasoning - Model checking approaches to AI - Planning via model checking - Model checking for multi-agent systems - Model checking for diagnosis - Model checking for games - Using concurrency models in AI (Process Algebras, Petri Nets, Statecharts,...) - AI approaches to model checking - AI approaches to the state explosion problem - Heuristics for model checking - AI approaches to automatic abstraction - Model checking for verification of AI systems - Requirements/specifications/properties for AI systems - Automated verification of AI systems - Model checking of multi-agent systems - Model checking of model-based systems - Model checking of knowledge-based systems - Tools related to any of these topics - Case studies related to any of these topics SUBMISSION The workshop notes will include original material. Archived material will also be considered for presentation but will not appear in the proceedings. Shorter papers are encouraged, particularly those exposing novel ideas or work in progress. Authors are invited to submit papers (11pt, letter or A4, no more than 12 pages long) in PostScript format or Adobe PDF by March 7, 2003 to the following e-mail address: mochart03(a)na.infn.it. The first page of each submission should carry the contact details of a nominated contact person, including email address. PARTICIPATION Participation will be by invitation. Potentially interested participants must submit a *short* position statement, indicating the reasons for their interest in the topics of the workshop to the e-mail address mochart03(a)na.infn.it, by April 1, 2003 IMPORTANT DATES AND DEADLINES - Deadline for the submission of papers: March 7, 2003. - Notification of acceptance/rejection of papers: March 30, 2003. - Deadline for the posotion statement: April 1, 2003 - Deadline for the receipt of camera-ready papers: May 15, 2003. ORGANIZING COMMITEE Massimo Benerecetti Dipartimento di Scienze Fisiche Universita di Napoli ``Federico II'' Via Cintia, Complesso Monte S. Angelo I-80126 Napoli, Italy e-mail: bene(a)na.infn.it http://people.na.infn.it/~bene/ Charles Pecheur RIACS / ASE Group NASA Ames Research Center, M/S 269-2 Moffett Field, CA 94035, U.S.A. e-mail: pecheur(a)ptolemy.arc.nasa.gov http://ase.arc.nasa.gov/pecheur =====================================================================

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Re: Template Haskell
by Yoann Padioleau 06 Jan '03

06 Jan '03

"Simon Peyton-Jones" <simonpj(a)microsoft.com> writes: > Folks > > Template Haskell is now being used by a few brave souls (they have to > build GHC from scratch), and I don't want to overload the Haskell > mailing list with nitty-gritty discussion about the finer points of TH. > > So Simon M has created a separate mailing list > > template-haskell(a)haskell.org i tried http://haskell.org/pipermail/template-haskell/ to see the archive of the mailing list but i get an error :(((( > > for Template Haskell discussion. Do join it if you are interested. You > can get to it via the usual Haskell mailing list page: > http://haskell.org/mailinglist.html > > I'll still post general announcements to the main Haskell list, though. > > Simon > _______________________________________________ > Haskell mailing list > Haskell(a)haskell.org > http://www.haskell.org/mailman/listinfo/haskell > -- Yoann Padioleau, INSA de Rennes, France, Opinions expressed here are only mine. Je n'écris qu'à titre personnel. **____ Get Free. Be Smart. Simply use Linux and Free Software. ____**

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