January 2004 - Haskell

Problems building experimental Unicode version of Hugs on Windows
by Graham Klyne 09 Jan '04

09 Jan '04

This message notes some edits I'm making to try and build the Dec2003 Hugs source kit with Unicode under MS-Windows (because I want to try and use HXML toolbox under Hugs). It also describes a problem I'm having with the experimental Unicode support under Windows. (I'm also thinking these notes might be helpful to anyone else who wants to build Hugs on Windows without using the Unix tools environment.) Using Microsoft Visual Studio, version 6, and supplied project files: (1) edit src/msc/options.h to include #define UNICODE_CHARS_1 (2) Change #if STDCALL_SUPPORTED to #ifdef STDCALL_SUPPORTED in: connect.h input.c static.c (3) Add the following files to the Visual Studio project: char.c edit.c errors.c evaluator.c goal.c machdep.c module.c observe.c opts.c script.c strutil.c (4) In version.c, changed the definition of VERSION_STRING to "Hugs-Unicode-20031206, so that this instantiation of Hugs will use a different registry key from the standard version for saving its options. Copied the resulting executable into the Hugs installation directory as hugs-unicode-20031206.exe (this being the date string in the source kit I was using, obtained from): http://www.golubovsky.org/software/hugs-patch/test-hugs98-Dec2003.tar.gz per: http://haskell.org/pipermail/hugs-users/2003-December/000508.html http://www.golubovsky.org/software/hugs-patch/hugs_unicode_test.html ... At this point, I run into a problem that appears to be (obscurely) related to the source changes that relate to Unicode support... If I start the modified program in the normal way, it appears to start OK. But if I change *any* option (e.g. :set -q), then stop and restart the program, I get: ERROR, a closing quote, '"', was expected FATAL ERROR, Unable to load Prelude and then the program crashes with an access violation, in module char.c, function freeConsCharTable, line 539: [[ static void local freeConsCharTable() { int i, j; for (j=1; j<NUM_LEVEL2; j++) >>> this line: >>> if (consCharTable[0][j]!=NULL) free(consCharTable[0][j]); for (i=1; i<NUM_LEVEL1; i++) if (consCharTable[i]!=NULL) { for (j=0; j<NUM_LEVEL2; j++) if (consCharTable[i][j]!=NULL) free(consCharTable[i][j]); free(consCharTable[i]); } ]] The debugger shows that "consCharTable[0]" is null (0). I note that this is new code which is part of the experimental Unicode support. If I delete the registry key created for the saved parameters, and restart Hugs, basic expressions seem to work fine. (e.g. simple string operations like concatenation were performed OK). ... The build procedure I've outlined above is essentially the same as one I used to create a version of Hugs with enlarged code storage space, which has been working fine for me. I'll leave it there, for now. #g ------------ Graham Klyne For email: http://www.ninebynine.org/#Contact

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COORDINATION2004: First Call for Participation
by Emilio Tuosto 09 Jan '04

09 Jan '04

[[ -- Apologies for multiple copies of this message -- ]] COORDINATION 2004 Call for Participation Sixth International Conference on Coordination Models and Languages 24-27 February 2004 Pisa, Italy http://www.di.unipi.it/Coordination2004 =============================================================================== Scope of the Conference The need for increasing programming productivity and rapid development of complex systems provides the pragmatic motivation for the development of coordination/orchestration languages and models. The intellectual excitement associated with such endeavours is rooted in the decades-old desire to leverage off increasingly higher levels of abstractions. Coordination-based methods provide a clean separation between individual software components and their interactions within their overall software organisation. Coordination is relevant in design, development, debugging, maintenance, and reuse of all complex concurrent and distributed systems. Specifically, coordination becomes paramount in the context of open systems, systems with mobile entities, and dynamically re-configurable evolving systems. Moreover, coordination models and languages focus on such key issues in Component Based Software Engineering as specification, interaction, and dynamic compositions. More recently, market trends brought on by the commercialisation of the World Wide Web, have fuelled a new level of interest in coordination-based approaches in industry. Applications like BizTalk, standards like the web services' WS-* family, and contending coordination standards like BEPL4WS and WSCI, are all examples of this phenomenon. This interest is opening up new opportunities both to apply coordination-based techniques to a broad class of applications as well as to grapple with potentially new kinds of requirements coming from internet-scale scenarios. The conference provides a forum for the discussion of fundamental principles and important innovations in the definition of coordination models and languages. The preliminary program of the conference can be found at http://www.di.unipi.it/Coordination2004/program.html Conference Location The Sixth International Conference on Coordination Models and Languages will be held in Pisa, Italy, at Dipartimento di Informatica, Via F. Buonarroti 2 (sala Gerace). Further information about the conference location may be found at the URL: http://www.di.unipi.it/Coordination2004/location.html Conference Accommodation and Registration Information about accommodation (reserving rooms in hotels specially booked for COORDINATION 2004 attendees) and registration for COORDINATION 2004 and the affiliated workshop (WS-FM 2004) is available at http://www.di.unipi.it/Coordination2004/inforeg.html Program co-chairs Rocco De Nicola (Univ. Firenze) Greg Meredith (Microsoft) Organising Chair Gianluigi Ferrari (Univ. Pisa) Program Committee: Roberto Amadio, Univ. Marseilles - France Farhad Arbab, CWI - The Netherlands Marcelo Bonsangue, Leiden University - The Netherlands Paolo Ciancarini, Univ. Bologna - Italy Gianluigi Ferrari, Univ. Pisa - Italy José Fiadeiro, Univ. Leicester - United Kingdom Chris Hankin, Imperial College - United Kingdom Jean-Marie Jacquet, Univ. Namur - Belgium Antonia Lopes, Univ. of Lisbon - Portugual Jeff Magee, Imperial College - United Kingdom George Papadopoulos, Univ. Cyprus - Cyprus Gian Pietro Picco, Politecnico di Milano - Italy Rosario Pugliese, Univ. Firenze - Italy Gruia-Catalin Roman, Washington University, St. Louis - USA Ant Rowstrom, Microsoft Cambridge - United Kingdom Vijay Saraswat, IBM Research - USA Carolin Talcott, SRI - USA Robert Tolksdorf, Free University of Berlin - Germany Herbert Wiklicky, Imperial College - United Kingdom Alan Wood, Univ. York - United Kingdom Franco Zambonelli, Univ. Modena - Italy Organising Committee Andrea Bracciali, Univ. Pisa - Italy Roberto Bruni, Univ. Pisa - Italy Antonio Cisternino, Univ. Pisa - Italy Dan Hirsch, Univ. Pisa - Italy Laura Semini, Univ. Pisa - Italy Emilio Tuosto, Univ. Pisa - Italy Further Information - COORDINATION2004 Web site: http://www.di.unipi.it/Coordination2004 - For questions: coordination2004(a)di.unipi.it

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getting the path to the executing program
by Hal Daume III 08 Jan '04

08 Jan '04

is there a function, related to getProgName, which returns the (absolute) path to the current program? basically, i want to be able to read a file which i know will be in the same directory as the current program, but not necessarily in the same directory that we're running it from. -- Hal Daume III | hdaume(a)isi.edu "Arrest this man, he talks in maths." | www.isi.edu/~hdaume

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Re: getting the path to the executing program
by Hal Daume III 08 Jan '04

08 Jan '04

Sadly, this doesn't seem to work: 9:26am albini:SVMseq/ cat Foo.hs module Main where import System.Environment main = getEnv "_" >>= putStrLn 9:27am albini:SVMseq/ ghc Foo.hs -o foo 9:27am albini:SVMseq/ ./foo Fail: does not exist Action: getEnv Reason: no environment variable File: _ On Thu, 8 Jan 2004, Christopher Milton wrote: > The environmental var "_" in $ENV{"_"} (pardon my Perlish) holds > the full path name of the command currently executing (itself), at > least on RedHat Linux and HP-UX, so you should be able to use > getEnv... I think... > > --- Hal Daume III <hdaume(a)ISI.EDU> wrote: > > is there a function, related to getProgName, which returns the (absolute) > > path to the current program? > > > > basically, i want to be able to read a file which i know will be in the > > same directory as the current program, but not necessarily in the same > > directory that we're running it from. > > > ===== > Christopher Milton > cmiltonperl(a)yahoo.com > -- Hal Daume III | hdaume(a)isi.edu "Arrest this man, he talks in maths." | www.isi.edu/~hdaume

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RE: class ??? with Haddock
by Simon Marlow 08 Jan '04

08 Jan '04

> > Am Donnerstag, 8. Januar 2004 11:02 schrieben Sie: > > > [...] > > > > > Anyway, you can use GHC to preprocess your source files > > before feeding > > > them to Haddock: > > > > > > $ ghc -E -cpp -D__HADDOCK__ Foo.hs -o Foo.raw-hs > > > > This only replaces all __HADDOCK__ occurences with 1 but > > doesn't process #ifdefs. > > Are you sure? It works for me, and it's what we use in GHC's > libraries. One thing I forgot to mention is that you also need to remove the pesky lines beginning with '#' that the C preprocessor leaves behind. Here's what we do in GHC: $ ghc -D__HADDOCK__ -E -cpp Foo.hs -o Foo.tmp $ sed -e 's/^#.*//' <Foo.tmp >Foo.raw-hs Cheers, Simon

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RE: class ??? with Haddock
by Simon Marlow 08 Jan '04

08 Jan '04

> Am Donnerstag, 8. Januar 2004 11:02 schrieben Sie: > > [...] > > > Anyway, you can use GHC to preprocess your source files > before feeding > > them to Haddock: > > > > $ ghc -E -cpp -D__HADDOCK__ Foo.hs -o Foo.raw-hs > > This only replaces all __HADDOCK__ occurences with 1 but > doesn't process #ifdefs. Are you sure? It works for me, and it's what we use in GHC's libraries. Cheers, Simon

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RE: class ??? with Haddock
by Simon Marlow 08 Jan '04

08 Jan '04

> How do I instruct Haddock to preprocess the Haskell files. > From your mail I > thought that Haddock would do so by default but it complains > at the first > #ifdef it sees. Unfortunately, I didn't find any Haddock > option similar to Hugs' -F. I should really put this in the manual, since it gets asked so often. Anyway, you can use GHC to preprocess your source files before feeding them to Haddock: $ ghc -E -cpp -D__HADDOCK__ Foo.hs -o Foo.raw-hs $ haddock -h Foo.raw-hs ... This also works to turn literate Haskell source into ... er ... illiterate source. Cheers, Simon

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Hugs with C preprocessor
by Wolfgang Jeltsch 08 Jan '04

08 Jan '04

Hello, I want to use Haskell files with #ifdef, #else and #endif preprocessor directives. I tried hugs -F "cpp -P" <source_file_name> but cpp complains about unterminated character constants. What is wrong? Wolfgang

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Combining distinct-thread state monads?
by Dr Mark H Phillips 08 Jan '04

08 Jan '04

Hi, I am still learning about monads. I have a problem in mind and am wondering whether state monads are able to solve it. The difficulty is that it would necessitate the interaction of two state threads and I'm not sure whether Haskell state monads allow this. Let me explain what I'm getting at. Consider two state threads. The first has each state being a non-negative int, thought of as a string of binary digits. The second thread has each state being a bool. Now I want to have a state monad which modifies both threads as follows. Consider input states i (the int thought of as binary string) and b (the bool), and output states i' and b'. b' = not (b && (i `mod` 2)) i' = i `div` 2 As you can see, both of these should be able to do update-in-place provided the above order is adhered to. We could achieve this using state monads where state is an (Int, Bool) pair. We would have one monad which did the first line, leaving i unchanged and a second monad which did the second line, leaving b' unchanged. But... what if before this interaction, the int thread and the bool thread were separate monads doing their own thing, and we just wanted to combine these threads briefly (using the above interaction) before letting the threads do their own thing again? Is this possible? Also, suppose we have previously defined an int thread monad which takes i, returns a value of i `mod` 2, and changes the state to i' = i `div` 2. Suppose also we have previously defined a bool thread monad which takes b, returns a nothing value, and changes the state to b' = not b. Can we use these two monads (each acting on different threads), to form a combined-interaction monad that does (same as before): b' = not (b && (i `mod` 2)) i' = i `div` 2 I hope this is possible. It would facilitate both code reuse and readability. However I fear that it is not, requiring one to instead explicitly rewrite the two separate thread monads into (Int, Bool) pair acting ones. Cheers, Mark.

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Second Call for Papers : ESSLLI'04 Student Session
by Paul Egré 08 Jan '04

08 Jan '04

!! We apologize for multiple copies of this message !! SECOND CALL FOR PAPERS ESSLLI-2004 STUDENT SESSION 9-20 August, 2004 in Nancy, France Deadline: February 22, 2004 http://esslli2004.loria.fr/ We are pleased to announce the Student Session of the 16th European Summer School in Logic, Language and Information (ESSLLI-2004), which will be held in Nancy from August 9-20, 2004. We invite submission of papers for presentation at the ESSLLI-2004 Student Session and for appearance in the proceedings. PURPOSE: This ninth ESSLLI Student Session will provide, like the previous editions, an opportunity for ESSLLI participants who are students to present their own work in progress and get feedback from senior researchers and fellow-students. The ESSLLI Student Session encourages submissions from students at any level, undergraduates (before completion of the Master Thesis) as well as postgraduates (before completion of the PhD degree). Papers co-authored by non-students will not be accepted. Papers may be accepted for full presentation (30 minutes including 5 to 10 minutes of discussion) or for a poster presentation. All the accepted papers will be published in the ESSLLI-2004 Student Session proceedings, which will be made available during the summer school. REQUIREMENTS: The Student Session papers should describe original, unpublished work, completed or in progress, that demonstrates insight, creativity, and promise. No previously published papers should be submitted. We welcome submissions with topics within the areas of Logic, Language and Computation. SUBMISSION DETAILS: Student authors are invited to submit a full paper, not to exceed 7 pages of length exclusive of references. Note that the length of the final version of the accepted papers will not be allowed to exceed 10 pages. The submissions will be reviewed by the student session programme committee and additional reviewers. A plain ASCII text version of the identification page should be sent separately, using the following format: Title: title of the submission First author: firstname lastname Address: address of the first author ...... Last author: firstname lastname Address: address of the last author Short summary: abstract (5 lines) Subject area (one or two of): Logic | Language | Computation In case the paper is being submitted to another conference or workshop, this must be clearly indicated on the identification page. The preferred formats of submissions are PostScript, PDF, or plain text, although other formats will also be accepted. In case of acceptance, the final version of the paper will have to be submitted in LaTeX format. The papers must use single column A4 size pages, 11pt or 12pt fonts, and standard margins. Submissions not in accordance with the specified formatting and length requirements may be subject to rejection without review. The paper and separate identification page must be sent electronically to: paulegre(a)magic.fr by FEBRUARY 22, 2004. PROGRAMME COMMITTEE: Laura Alonso i Alemany (Universitat de Barcelona, Barcelona) Carlos Areces (LORIA, Nancy) Jaume Baixeries (Universitat Politècnica de Catalunya, Barcelona) Willem Comradie (Rand Afrikaans University, South Africa) Benoit Crabbé (LORIA, Nancy) Paul Egré (IHPST, Université Paris 1, IJN) Judit Gervain (SISSA, Trieste) Bart Geurts (University of Nijmegen, Nijmegen) Ivana Kruijff-Korbayova (Universität des Saarlandes, Saarbrücken) Marco Kuhlmann (Universität des Saarlandes, Saarbrücken) Mª Magdalena Ortiz de la Fuente (Universidad de las Americas, Puebla) Benjamin Spector (Laboratoire de Linguistique Formelle, Université Paris 7, ENS) IMPORTANT DATES: Deadline for submission of papers : February 22, 2004. Authors notifications : April 19, 2004. ESSLLI early registration : May 1, 2004. Final papers for proceedings : May 15, 2004. ESSLLI-2004 Student Session : August 9-20, 2004. ESSLLI-2004 INFORMATION: In order to present a paper at ESSLLI-2004 Student Session, at least one student author of each accepted paper has to register as a participant at ESSLLI-2004. The authors of accepted papers will be eligible for reduced registration fees even after the deadline for early registration. For all information concerning ESSLLI-2004, please consult the ESSLLI-2004 main website at http://esslli2004.loria.fr/ For more information about the ESSLLI'04 student session, consult the ESSLLI'04 student session website at: http://lingua.fil.ub.es/~lalonso/stusESSLLI04/ If you have any further question about the student session, do not hesitate to contact us: Laura Alonso i Alemany Paul Egré lalonso(a)fil.ub.es paulegre(a)magic.fr Departament de Lingüística General IHPST / Université Paris 1 / Universitat de Barcelona Institut Jean-Nicod Institut Histoire et Philosophie des Sciences et Techniques Gran Via de les Corts Catalanes, 585 13, rue du Four 08007 Barcelona, SPAIN 75006 Paris, FRANCE telph: +34 93 403 56 93 telph: + (33) (0)1 43 54 60 36 fax: +34 93 318 98 22 fax: + (33) (0)1 44 07 16 49

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