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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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RE: realToFrac vs. fromRealFrac
by Simon Peyton-Jones 05 Feb '01

05 Feb '01

This is already noted as a typo in the typos draft: http://research.microsoft.com/~simonpj/haskell/haskell98-bugs.html Simon | -----Original Message----- | From: Manuel M. T. Chakravarty [mailto:chak@cse.unsw.edu.au] | Sent: 03 February 2001 12:35 | To: haskell(a)haskell.org | Subject: realToFrac vs. fromRealFrac | | | I am not sure whether the following issue has already been | mentioned earlier. | | Chapter 6 ``Predefined Types and Classes'' of The Report | says at its very end, | | Also available are the following coercion functions: | | fromIntegral :: (Integral a, Num b) => a -> b | fromRealFrac :: (RealFrac a, Fractional b) => a -> b | | (`fromRealFrac' is also defined in Figure 7.) | | However, in Appendix A ``Standard Prelude'', we have | | realToFrac :: (Real a, Fractional b) => a -> b | realToFrac = fromRational . toRational | | instead of a definition for `fromRealFrac'. | | Both GHC and Hugs go by Appendix A. What was the original | intention? | | Cheers, | Manuel | | _______________________________________________ | Haskell mailing list | Haskell(a)haskell.org | http://www.haskell.org/mailman/listinfo/haskell |

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PLI 2001 Announcement
by Rosario Pugliese 05 Feb '01

05 Feb '01

[Apologies for multiple copies] ---------------------------------------------------------------- PLI 2001 Principles, Logics, and Implementations of high-level programming languages (Sponsored by ACM) Firenze, ITALY September 2 - 8, 2001 http://music.dsi.unifi.it/pli01/ The colloquium on Principles, Logics, and Implementations of high- level programming languages is a collection of conferences and workshops aimed at the advancement of high-level programming languages. The events composing PLI will cover a spectrum of topics important to language development and use, including issues such as semantics, design, analysis, implementation, and application. Theoretical issues relevant to language design and programming will be represented. Implementation questions will provide an emphasis on compilation methods, distributed computation and static debugging techniques. There will also be a focus on industrial and educational applications. Conferences: ICFP (September 3-5) Int. Conf. on Functional Programming General chair: Benjamin Pierce (Univ. Pennsylvania) Program chair: Xavier Leroy (INRIA Rocquencourt) PPDP (September 5-7) Int. Conf. on Principles and Practice of Declarative Programming Conference chair: Rocco De Nicola (Univ. Firenze) Program chair: Harald Søndergaard (Univ. Melbourne) Workshops: · Multilanguage Infrastructure and Interoperability (BABEL) · ERLANG Workshop · Fixed Points in Computer Science (FICS) · HASKELL Workshop · Quantitative Aspects of Programming Languages (QAPL) · Rule-Based Programming (RULE) · Semantics, Applications, and Implementation of Program Generation (SAIG) · Scheme and Functional Programming (SCHEME) · Verification and Computational Logic (VCL) Submission deadline for ICFP and PPDP: March 15, 2001 Workshops chair: Betti Venneri (Univ. Firenze) Publicity chair: Rosario Pugliese (Univ. Firenze) Organizing Committee: Gianni Aguzzi (Univ. Firenze, co-chair), Giorgio Ghelli (Univ. Pisa, co-chair), Lorenzo Bettini (Univ. Firenze), Michele Loreti (Univ. Firenze), Dario Colazzo (Univ. Pisa) Contact Information: pli-inf(a)gdn.dsi.unifi.it Conference Venue: Auditorium Banca Toscana, Via Panciatichi, 87 (Firenze Nova), Firenze, ITALY

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MD5 in Haskell
by Ian Lynagh 03 Feb '01

03 Feb '01

I apologise if this is off topic for this list - I haven't been here long. Someone recently mentioned that the MD5 function in GHC uses C code to do the work so returns an IO String rather than a String. I have written an MD5 implementation in pure Haskell code (following the RFC - I don't know if a better optimised version could be written although I may look into this). I've put the code at http://c93.keble.ox.ac.uk/~ian/md5/ License is GPL. Ian

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realToFrac vs. fromRealFrac
by Manuel M. T. Chakravarty 03 Feb '01

03 Feb '01

I am not sure whether the following issue has already been mentioned earlier. Chapter 6 ``Predefined Types and Classes'' of The Report says at its very end, Also available are the following coercion functions: fromIntegral :: (Integral a, Num b) => a -> b fromRealFrac :: (RealFrac a, Fractional b) => a -> b (`fromRealFrac' is also defined in Figure 7.) However, in Appendix A ``Standard Prelude'', we have realToFrac :: (Real a, Fractional b) => a -> b realToFrac = fromRational . toRational instead of a definition for `fromRealFrac'. Both GHC and Hugs go by Appendix A. What was the original intention? Cheers, Manuel

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Fundeps and quantified constructors
by nubie nubie 03 Feb '01

03 Feb '01

So I want to have a polymorphic Collection type, just because. > class Collection c e | c -> e where > empty :: c > put :: c -> e -> c > data SomeCollection e = forall c . Collection c e => MakeSomeCollection c Hugs (February 2000) doesn't like it. It says Variable "e" in constraint is not locally bound I feel that e *is* bound, sort of, because c is bound and there's a fundep c->e. Who's wrong, me or Hugs? The following things work as expected: > data IntCollection = forall c . Collection c Int => MakeIntCollection c > data AnyCollection = forall c e . Collection c e => MakeAnyCollection c Regards -- anatoli __________________________________________________ Get personalized email addresses from Yahoo! Mail - only $35 a year! http://personal.mail.yahoo.com/

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Notes of haskell
by Luis Ricardo 02 Feb '01

02 Feb '01

I shearch notes of haskell. Luis Ricardo Portugal

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AW: What does "Compiled code too complex" error message of Hugs m ean?
by Laaser Christian 02 Feb '01

02 Feb '01

I never built Hugs on Windows before :-( ... and a trial to do so with cygwin/gcc was unsuccessful. Have you got a precompiled binary for Win (hugs.exe) with these settings, which you could send me / I could download from somewhere? Christian > -----Urspr> üngliche Nachricht----- > Von: Jan Kort [SMTP:kort@wins.uva.nl] > Gesendet am: Mittwoch, 31. Januar 2001 13:34 > An: Laaser Christian > Cc: 'haskell(a)haskell.org' > Betreff: Re: What does "Compiled code too complex" error message of Hugs mean? > > Laaser Christian wrote: > > > > When loading some Haskell files with Hugs, I get the error message "Compiled code too complex". However, the compilation with GHC 4.08.1 succeeds. > > What does this message mean? What can I do about it? > > > > You can grep for that sentence in "hugs98/src", it will point to the > file "machine.c". There you will see it says "if (nextLab>=NUM_FIXUPS) ...". > So grep for "NUM_FIXUPS" it will point to the file "prelude.h". I > think the default value is 400, you should increase it to 1000 or so. > I have it at 10000, but that's probably not necesary in your case > and if you increase constants too much starting up Hugs will become > slower. > > Jan

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ESSLLI 2001 Call for Workshop Abstracts: Finite State Methods in Natural Language Processing
by Ahti Pietarinen 02 Feb '01

02 Feb '01

CALL FOR ABSTRACTS Finite State Methods in Natural Language Processing ESSLLI Workshop, August 20-24 2001, Helsinki Description: Finite state methods are used in various areas of linguistic computation, including tokenization, lexicography, spell checking, part of speech tagging, speech recognition, grapheme to phoneme conversion, computational phonology and morphology, as well as computational syntax. In recent years the use of finite state methods has increased both in practical applications (such as in morphological analyzers for a variety of languages), as well as in more theoretical approaches (such as in recent attempts to formalize optimality-theoretic analyses in phonology by finite-state means). The aim of the workshop is to bring together researchers and Ph.D. students working with finite-state methods within natural language processing and computational linguistics. The workshop belongs to the program of the 13th European Summer School in Logic, Language and Information (ESSLLI) which is organized at the University of Helsinki from August 13 until August 24, 2001 (see the home page http://www.helsinki.fi/esslli for more information). Submission guidelines: Extended abstracts (up to four pages) for forty-five minute talks are invited from all areas of interest for the workshop. The abstract should be submitted by e-mail to Gertjan van Noord, vannoord(a)let.rug.nl before the deadline given below, in Postscript or PDF. Note that all participants of the workshop must register for the ESSLLI summer school. Organisers: Lauri Karttunen Xerox Research Kimmo Koskenniemi University of Helsinki Gertjan van Noord University of Groningen Important Dates: Submission deadline: April 27, 2001 Notification of contributors: May 15, 2001 Workshop Dates: August 20-24, 2001 Sponsor The workshop is co-financed by the NWO PIONIER project Algorithms for Linguistic Processing. Further info at http://www.let.rug.nl/~vannoord/alp/

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