- Haskell - Haskell.org

Implementing the Show class for a Hash
by Shlomi Fish 07 Feb '01

07 Feb '01

Hi! I've written a hash implementation in pure Haskell. The hash is more of a collection of elements organized in a table of linked lists, and it can serve as a dictionary by having each one be a key-value pair. However, I ran into problems when implementing the show function and hugs keeps reporting errors. Can anybody implement it for me based on the hash implementation, and the function which I have commented out? The URL for the code is : http://techst02.technion.ac.il/~shlomif/haskell/Hash/Hash.hs Regards, Shlomi Fish ---------------------------------------------------------------------- Shlomi Fish shlomif(a)vipe.technion.ac.il Home Page: http://t2.technion.ac.il/~shlomif/ Home E-mail: shlomif(a)techie.com The prefix "God Said" has the extraordinary logical property of converting any statement that follows it into a true one.

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Announcing haskelldoc
by Henrik Nilsson 06 Feb '01

06 Feb '01

Dear Haskellers, At the recent Haskell Implementors' meeting in Cambridge, UK, it was decided that it would be useful to have a standard for embedded Haskell documentation. Such standards, and associated tools for extracting and formating the documentation in various ways, exists for other languages like Java and Eiffel and have proven to be very useful. Some such tools also exist (and are being actively developed) for Haskell, but there is as yet no generally agreed upon standard for the format of the embedded documentation as such. To address this, a mailing list has been started with the aim of defining a standard for embedded Haskell documentation, and possibly also related standards which would facilitate the development of various tools making use of such documentation (formatters, source code browsers, search tools, etc.). We feel that it is important to involve all who might be interested in this work at an early stage, so that as many aspects as possible can be taken into consideration, and so that the proposal for a standard which hopefully will emerge has a reasonable chance of gaining widespread support. Thus, You are hereby cordially invited to join haskelldoc(a)haskell.org. To join, just goto http://www.haskell.org/mailman/listinfo/haskelldoc. Best regards, Armin Groesslinger <groessli(a)fmi.uni-passau.de> Simon Marlow <simonmar(a)microsoft.com> Henrik Nilsson <nilsson(a)cs.yale.edu> Jan Skibinski <jans(a)numeric-quest.com> Malcolm Wallace <malcolm(a)abbess.demon.co.uk>

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RE:
by Andrew Tolmach 06 Feb '01

06 Feb '01

Christoph Hermann <herrmann(a)fmi.uni-passau.de> wrote: > > Dear Haskellers, > > >>>>> "Simon" == Simon Peyton-Jones <simonpj(a)microsoft.com> writes: > > Simon> We agreed that it would be a Jolly Good Thing if GHC > Simon> could be persuaded to produce GHC-independent Core output, > Simon> ready to feed into some other compiler. For example, > Simon> Karl-Filip might be able to use it. ANDREW will write a > Simon> specification, and implement it. > > a good idea. Before ANDREW will put a lot of effort in the > specification > and implementation, it would be good to have a discussion > about the core > representation that is gradually evolving. Indeed, I plan to publish a draft specification (quite soon) and will be delighted to get feedback from the community before investing heavily in implementation. I'm very glad to hear that others are interested! > There is the risk > that the representation, made by insiders, will be too complicated > to be used by several other people as I feel the core output > currently produced by GHC is. Actually, I am something of an outsider myself (though physically located near a bunch of insiders just at the moment!) so I hope I'll be sensitive to this point. But perhaps Simon should not have written "GHC-independent" Core output; my goal is to expose GHC's existing Core language, or something very close to it, rather than to invent an ideal Core Haskell. So some GHC-specific complexities may be unavoidable. > It would be good to put all stuff related to this topic onto a > WWW page, containing links to relevant papers, conventions, > example pairs (Haskell source,core equivalent) which can be > discussed. A good idea; I'll set up such a page and put the draft there to get things started. > A toy interpreter (e.g., using happy) which > interprets the core language and which is written with the goal of > documentation, not under efficiency aspects, may be helpful. Yes, I had already thought of doing this. Perhaps a type-checker too. > I'm not sure whether you like the idea, but a quick solution for > a small subset of Haskell would, in my opinion, be smarter > to the user, since her or she can get used to the representation > and we have something concrete to discuss. Well, yes. But the entire core language *is* really fairly small, so I am optimistic that a fairly complete job can be done in fairly short order. Cheers, Andrew Tolmach

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fixST in GHC
by Pedro Baltazar Vasconcelos 06 Feb '01

06 Feb '01

Hello all, I'm experimenting with the ST monad GHC/Hugs extension and came across a puzzling omisson: in GHC 4.06 if I import the LazyST module instead of the standard one then the knot-tying fixST combinator is not defined. Aparently the reason for this omisson is not documented in the ghc manual... BTW, in Hugs both LazyST/ST define fixST. Regards, Pedro Vasconcelos.

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8th Static Analysis Symposium : Last CFP
by Radhia Cousot 06 Feb '01

06 Feb '01

========My apologies for duplicates of this announcement========= ================================================================= = = = Call For Papers = = = = 8th INTERNATIONAL STATIC ANALYSIS SYMPOSIUM = = = = = = La Sorbonne, Paris = = 16-18 July, 2001 = = = = http://www.ens.fr/sas01/ = = = ================================================================= Static Analysis is increasingly recognized as a fundamental technique for high performance implementations and verification systems of high-level programming languages. The series of Static Analysis Symposia has served as the primary venue for presentation of theoretical, practical and applicative in the area. The Eigth International Static Analysis Symposium (SAS2'01) will be held at La Sorbonne in Paris and followed immediately at La Mutualite by the Thirteenth Conference on Computer Aided Verification (CAV'01, http://www.lsv.ens-cachan.fr/cav01/}. Previous symposia were held in Santa Barbara, Venice, Pisa, Paris, Aachen, Glasgow and Namur. The technical program for SAS'01 will consist of invited lectures, tutorials, panels, presentations of refereed papers, and software demonstrations. Contributions are welcome on all aspects of Static Analysis, including, but not limited to abstract interpretation data flow analysis verification systems optimizing compilers abstract domains program specialization theoretical frameworks type inference abstract model checking complexity analysis abstract testing security analysis Submissions can address any programming paradigm, including concurrent, constraint, functional, imperative, logic and object-oriented programming. Survey papers that present some aspect of the above topics with a new coherence are also welcome. Submitted papers must not substantially overlap with papers that have been published or that are simultaneously submitted to a journal or a conference with a refereed proceedings. Submitted papers should be at most 15 single space 11-point font pages excluding bibliography and well-marked appendices. Program committee members are not required to read any appendices, and so a paper should be intelligible without them. The papers should be submitted as PostScript documents that are interpretable by Ghostscript and/or in PDF format, and they must be printable on both US letter and A4 paper; to facilitate this, extensive use of special fonts and colors should be avoided. Submissions should arrive by February 15, 2001. All submissions must be done electronically at http://www.ens.fr/sas01/. Authors will be notified of the acceptance or rejection of their papers by April 2, 2001. Final versions of the accepted papers must be received in electronic form by April 30, 2001. Important Dates: Submission: February 15, 2001. Notification: April 2, 2001. Final Version: April 30, 2001. Program Chair: Patrick Cousot Ecole Normale Superieure Departement d'Informatique 45, Rue d'Ulm 75230 Paris Cedex 05, France Email: sas01(a)ens.fr Phone: & + 33 1 44 32 20 64 Fax: & + 33 1 44 32 21 52 Program Committee: M. Bruynooghe (KU, Leuven) P. Cousot (ENS, Paris) G. Fil'e (Padova) M. Hagiya (Tokyo) C. Hankin (IC, London) L. Hendren (McGill, Montreal) M. Hermenegildo (UPM, Madrid) N. Jones (DIKU, Denmark) J. Larus (Microsoft, Redmond) J. Palsberg (Purdue) S. Sagiv (Tel Aviv) D. Sands (Chalmers, Goteborg) D. Schmidt (Kansas S.) M.L. Soffa (Pittsburgh) H. Sondergaard (Melbourne) R. Wilhelm (Saarbruken) K. Yi (KAIST, Taejon) General Chair: Radhia Cousot CNRS & Ecole polytechnique rcousot(a)lix.polytechnique.fr

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"Job Adverts" on haskell.org
by Olaf Chitil 06 Feb '01

06 Feb '01

Haskell.org has a page "Job Adverts". http://www.haskell.org/jobs.html This page lists university and industry positions for people who want to work with Haskell. However, besides that, it shall also contain other kinds of adverts. Haskell is based on open source software to which a large number of people contribute. If you are working on some Haskell project and could do with some help, then advertise here (and on the Haskell mailing list). Even more importantly: If you built some Haskell software and unfortunately no longer feel able to maintain it, then please advertise here (and on the Haskell mailing list) for new people to take it over and give it a home. Thus we may alleviate the problem of the large number of Haskell tools and libraries that are half complete and no longer maintained. Mail John and me if you want to place an advert on the page. mailto:peterson-john@cs.yale.edu,olaf@cs.york.ac.uk Cheers, Olaf -- OLAF CHITIL, Dept. of Computer Science, University of York, York YO10 5DD, UK. URL: http://www.cs.york.ac.uk/~olaf/ Tel: +44 1904 434756; Fax: +44 1904 432767

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how to set default editor in hugs 98 for win and linux
by andrew long 05 Feb '01

05 Feb '01

I've just started to use hugs in both the windows 98 and linux environments and wanted to assign notepad and kwrite as the default editors to their respective os'. If you could enlighten me on this setup procedue for both systems ot wuld be greatly appreciated a.p.long(a)ncl.ac.uk cheers big a

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binary files in haskell
by Timmy Douglas 05 Feb '01

05 Feb '01

I was wondering if anyone here has a solution for writing binary files that works in hugs and ghc that doesn't require getting libs. I looked at this page: http://haskell.cs.yale.edu/ghc/docs/latest/set/sec-ioexts.html and the haskell.org libraries page and I didn't see anything. the ghc documentation didn't provide any examples so I was unable to figure out how to write a binary file.

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Haskell Implemetors Meeting
by Simon Peyton-Jones 05 Feb '01

05 Feb '01

Gentle Haskellers, A few weeks ago (following POPL) there was an informal meeting of some people involved in implementing Haskell. In this message I summarise some of the things we discussed, because I think many of them will be of general interest. People with actions are in CAPITALS. Key: MANUEL Manuel Chakravarty SIGBJORN Sigbjorn Finne JOHN John Launchbury ANDREW Andrew Tolmach MALCOLM Malcolm Wallace HENRIK Henrik Nilsson OLAF Olaf Chitil SIMON M Simon Marlow SIMON PJ Simon Peyton Jones Simon ================================================================= Haskell Report ~~~~~~~~~~~~~~ SIMON PJ still hasn't put out the revised H98 report. Jump to it! Foreign Function Interface ~~~~~~~~~~~~~~~~~~~~~~~~~~ Going splendidly, but needs writing up as a proper "Blessed Addendum" to the H98 report, so that compilers can say "I implement H98 plus FFI". MANUEL agreed to be Editor for the Addendum, and drive the process. H/Direct and Green Card: SIGBJORN is going to work at Galois, and will continue to look after and develop these tools. Indeed, he's already started hacking on them again. Hooray! Haskell implementation ~~~~~~~~~~~~~~~~~~~~~~ Hugs: OGI in maintenance mode. There's a danger that Hugs will gradually die, which none of us want. One idea: advertise openly for a home for Hugs. JOHN will take this suggestion to OGI. nhc: Being actively maintained and developed at York GHC: 4.08.2 release imminent Simon M and Julian gave a demo of the upcoming interactive GHCi demo; release expected in a month or two. We agreed that it would be a Jolly Good Thing if GHC could be persuaded to produce GHC-independent Core output, ready to feed into some other compiler. For example, Karl-Filip might be able to use it. ANDREW will write a specification, and implement it. MANUEL is writing an inside-the-monster roadmap. He'll put it in fptools/ghc somewhere, so others can add to it. Haskell Libraries ~~~~~~~~~~~~~~~~~ MALCOLM produced a proposal for a (tiny) language extension that would give us a hierarchical name space for modules (a la Java). We loved it. He will refine it into a concrete document to circulate more widely. We agreed (again) about the importance of libraries. The "hslibs" libraries are a good start. They are *not* part of GHC, even though they happen to live in the same CVS repository. We agreed they should stay there, but should have a less GHC-specific build/test system. We appointed a troika of Library Supremos, namely MALCOLM, SIMON M, ANDY Specific tasks: - get closure on Malcolm's module-naming proposal - agree hslibs hierarchy - define documentation standards - act as gatekeepers for contributions SIMON M will create a mailing list for library discussions. Graphical user interfaces ~~~~~~~~~~~~~~~~~~~~~~~~~ We got a useful taxomomy: -------------------------------------------------------- High-level Fran/Tk Fudgets (Haggis) -------------------------------------------------------- Medium-level Clean Object I/O School of abstractions [GUI] Expression (SOE) [Graphics] -------------------------------------------------------- Low-level veneers HOpenGL Gtk Haskell/Tk Win32 X on existing [Graphics] libraries -------------------------------------------------------- Low-level veneers are going well -- but they are low level. High-level abstractions are pretty experimental. We need a medium-level GUI library. Peter Achten's port of the Clean Object I/O system looks like a great candidate. Well documented, lots of experience in use, about the right level. SIMON PJ to seek agreement from Nijmegen, and then advertise for someone to complete the port. OLAF will articulate the above taxonomy on haskell.org HaskellDoc ~~~~~~~~~~ We all loved Armin Groesslinger's HDoc tool. HENRIK will get in touch with him to invite him to collaborate on a standard tool we can all use. (Of course, it's up to him.) Two specific ideas: Take a Haskell source file into some XML-stuff, which can then be rendered in various ways. (Rather than going straight to HTML.) Use standard pragma syntax: {-# DOC ... #-} [Post meeting note: mailing list at <http://www.haskell.org/mailman/listinfo/haskelldoc> http://www.haskell.org/mailman/listinfo/haskelldoc ] Debugging ~~~~~~~~~ Hat (York): Expect a release in the Spring. In the summer they hope for a first cut at at an implementation-portable version Hood: ANDY plans to release his graphical version IDE ~~~ Galois are interested in working on Haskell-in-Visual-Studio. Haskell.org ~~~~~~~~~~~ Idea: have a "job adverts" page on haskell.org, for tasks that need doing. For example: * Integrate Haskell with "Source Navigator" * Offer libraries * Complete Clean I/O port * Contribute nofib programs * Contribute validation programs Action OLAF.

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LAST CfP: ESSLLI 2001 Student Session
by Kristina Striegnitz 05 Feb '01

05 Feb '01

!!! Concerns all students in Logic, Linguistics and Computer Science !!! !!! Please circulate and post among students !!! We apologize, if you receive this message more than once. ESSLLI 2001 STUDENT SESSION LAST CALL FOR PAPERS August 13-24 2001, Helsinki, Finland Deadline: February 18, 2001 http://www.coli.uni-sb.de/~kris/esslli We are pleased to announce the Student Session of the 13th European Summer School in Logic, Language and Information (ESSLLI 2001) organized by the University of Helsinki under the auspices of the European Association for Logic, Language and Information (FoLLI). ESSLLI 2001 will be held at the University of Helsinki in August 2001. We invite submission of papers for presentation at the ESSLLI 2001 Student Session and for appearance in the proceedings. PURPOSE: This sixth ESSLLI Student Session will provide, like the other 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, from 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 10 minutes of discussion) or for a poster presentation. The accepted papers will be published in the ESSLLI 2001 Student Session proceedings, which will be made available during the summer school. KLUWER BEST PAPER AWARD: As in previous years, the best paper will be selected by the program committee and will be offered a prize by Kluwer Academic Publishers consisting in 1000 Dfl worth of books. 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. All topics within the six ESSLLI subject areas (Logic, Language, Computation, Logic & Language, Logic & Computation, Language & Computation) are of interest. FORMAT OF SUBMISSION: Student authors should submit an anonymous extended abstract headed by the paper title, not to exceed 5 pages in length exclusive of references and send a separate identification page (see below). Note that the length of the full papers will not be allowed to exceed 10 pages. Since reviewing will be blind, the body of the abstract should omit author names and addresses. Furthermore, self-references that reveal the author's identity (e.g., "We previously showed (Smith, 1991)... ") should be avoided. It is possible to use instead references like "Smith (1991) previously showed...". For any submission, 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 of): Logic | Language | Computation | Logic and Language | Logic and Computation | Language and Computation If necessary, the program committee may reassign papers to a more appropriate subject area. The submission of the extended abstract should be in one of the following formats: PostScript, PDF, RTF, or plain text. But note that, in case of acceptance, the final version of the paper has to be submitted in LaTeX format. Please, use A4 size pages, 11pt or 12pt fonts, and standard margins. Submissions outside the specified length and formatting requirements may be subject to rejection without review. The extended abstract and separate identification page must be sent by e-mail to: kris(a)coli.uni-sb.de by FEBRUARY 18, 2001 ESSLLI 2001 INFORMATION: In order to present a paper at ESSLLI 2001 Student Session, at least one student author of each accepted paper has to register as a participant at ESSLLI 2001. The authors of accepted papers will be eligible for reduced registration fees. For all information concerning ESSLLI 2001, please consult the ESSLLI 2001 web site at http://www.helsinki.fi/esslli. IMPORTANT DATES: Deadline for submission of abstracts: February 18, 2001. Authors Notifications: April 17, 2001. Final version due: May 18, 2001. ESSLLI-2001 Student Session: August 13-24, 2001. PROGRAM COMMITTEE: Raffaella Bernardi, University of Utrecht (Logic & Language) Patrick Blackburn, Loria Nancy (Logic & Language) Gilles Dowek, INRIA (Computation) Ruth Kempson, King`s College London (Language) Carsten Lutz, University of Aachen (Logic & Computation) Ani Nenkova, Columbia University (Logic) Ilkka Niemel�, Helsinki University of Technology (Logic & Computation) Malvina Nissim, University of Pavia (Language) Susanne Salmon-Alt, Loria, Nancy (Language & Computation) Jan Schwinghammer, University of the Saarland (Computation) Kristina Striegnitz, University of the Saarland (Chair) Yde Venema, University of Amsterdam (Logic) Shuly Wintner, University of Haifa (Language & Computation) For any question concerning the ESSLLI 2001 Student Session, please, do not hesitate to contact me: Kristina Striegnitz Computational Linguistics, University of the Saarland, Germany phone: +49 - 681 - 302 4503 email: kris(a)coli.uni-sb.de

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