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Call for Papers: 10th Static Analysis Symposium
by Radhia Cousot 06 Jan '03

06 Jan '03

---------------------------------------------------------------------- Call for Papers SAS '03 10th Annual International Static Analysis Symposium June 11-13, 2003 : San Diego, California http://www.lix.polytechnique.fr/~radhia/sas03/index.html Federated Computing Research Conference FCRC 2003 http://www.acm.org/sigs/conferences/fcrc/ ---------------------------------------------------------------------- Static Analysis is increasingly recognized as a fundamental tool for high performance implementations and verification systems of programming languages. The series of Static Analysis Symposia has served as the primary venue for presentation of theoretical, practical, and application advances in the area. The 10th International Static Analysis Symposium SAS'03 will be held at the Town and Country Resort & Conference Center in San Diego (USA) as part of the Federated Computing Research Conference FCRC 2003. Previous symposia were held in Madrid, Paris, Santa Barbara, Venice, Pisa, Paris, Aachen, Glasgow and Namur. The technical program for SAS'03 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, program transformation, abstract domains, optimizing compilers, theoretical frameworks, type inference, abstract model checking, complexity analysis, abstract testing, security analysis, mobile code, hardware systems, distributed systems, embedded systems. 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. Papers must describe original work, be written and presented in English, and must not substantially overlap with papers that have been published or that are simultaneously submitted to a journal or a conference with refereed proceedings. Submission instructions: All submissions must be performed electronically at http://www.lix.polytechnique.fr/~radhia/sas03/submission.html. Submitted papers should be at most 15 pages excluding bibliography and well-marked appendices. Program committee members are not required to read the appendices, and thus papers should be intelligible without them. Publication: The proceedings will be published by Springer in the Lecture Notes in Computer Science series (see http://www.springer.de/comp/lncs/authors.html for the LNCS Author's Instructions). Thus, adhering to that style already in the submission is strongly encouraged. Papers should be submitted either in PostScript or PDF format and they should be interpretable by Ghostscript or Acrobat Reader. Papers must be printable on either A4 paper or US letter, and preferably on both. Selected papers will be published in a special issue of a journal. Important dates: Deadline for submissions : February 7, 2003. Notification of acceptance or rejection : March 18, 2003. Deadline for reception of the final versions : March 30, 2003. The conference : June 11-13, 2003. Program Committee: Radhia Cousot (Chair) CNRS and Ecole polytechnique, France Alex Aiken University of California, Berkeley, USA Luddy Harrison Intel Corporation, USA Susan Horwitz University of Wisconsin-Madison, USA Andy King University of Kent, UK Giorgio Levi University of Pisa, Italy Michael Lowry NASA Ames Research Center, USA Laurent Mauborgne Ecole normale superieure, France Alan Mycroft Cambridge University, UK Germán Puebla Technical University of Madrid, Spain Francesco Ranzato University of Padova, Italy Shmuel Sagiv Tel-Aviv University, Israel David Sands Chalmers University of Technology and University of Goteborg, Sweden Helmut Seidl University of Trier, Germany Mary Lou Soffa University of Pittsburgh, USA Harald Søndergaard University of Melbourne, Australia Contact info: radhia.cousot(a)polytechnique.fr

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Web Application Development
by Dominic Steinitz 05 Jan '03

05 Jan '03

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 have been modifying it. However, I am spending a lot of time tracking down errors at run time which a type system would have caught. It's particularly easy to write PHP code which generates SQL calls which look correct (by looking in the MySQL log) but actually put garbage in the database. So my question is: what should I do to re-write this in Haskell? >From the discussion on this mailing list in June and reading through the libraries section of haskell.org, I think there are the following options: HTML 1. Use Wash/CGI but maybe somehow move to mod_haskell if the webserver performance isn't adquate. SQL 2. Use MySQL-HS which requires HaskellDirect or use HSQL. I'd be very grateful for any advice and any progress as a result of the discussion in June. Dominic Steinitz

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tuple component functions
by trb＠eastpac.com.au 03 Jan '03

03 Jan '03

S.D.Mechveliani writes: > As Haskell has the standard functions fst, snd to decompose (a,b), > maybe, it worths to provide also > tuple31, tuple31, tuple31, > ... > tuple51, tuple52, tuple53, tuple54, tuple55 > > for the tuples of n = 3,4,5 ? I've found some of these useful, except I named them differently: > fst3 :: (a,b,c) -> a > fst3 (x,_,_) = x > snd3 :: (a,b,c) -> b > snd3 (_,x,_) = x > thd3 :: (a,b,c) -> c > thd3 (_,_,x) = x .... never got around to quadruples etc. I also defined (some of these may be untested): > tripl :: a -> (a,a,a) > tripl x = (x,x,x) > curry3 :: ((a, b, c) -> d) -> a -> b -> c -> d > curry3 f x y z = f (x, y, z) > uncurry3 :: (a -> b -> c -> d) -> ((a, b, c) -> d) > uncurry3 f t = f (fst3 t) (snd3 t) (thd3 t) > applyTriple :: (a -> b, a -> c, a -> d) -> a -> (b,c,d) > applyTriple (f,g,h) x = (f x, g x, h x) > cross3 :: (a -> b, c -> d, e -> f) -> (a,c,e) -> (b,d,f) > cross3 (f,g,h) (x,y,z) = (f x, g y, h z) > mapTriple :: (a -> b) -> (a, a, a) -> (b, b, b) > mapTriple = cross3 . tripl > applyFst3 :: (a -> b) -> (a, c, d) -> (b, c, d) > applyFst3 f = applyTriple (f . fst3, snd3, thd3) > applySnd3 :: (a -> b) -> (c, a, d) -> (c, b, d) > applySnd3 f = applyTriple (fst3, f . snd3, thd3) > applyThd3 :: (a -> b) -> (c, d, a) -> (c, d, b) > applyThd3 f = applyTriple (fst3, snd3, f . thd3) > applyArgs3 :: (a -> b) -> (c -> d) -> (e -> f) -> (b -> d -> f -> g) -> (a -> c -> e -> g) > applyArgs3 af1 af2 af3 f = \x y z -> f (af1 x) (af2 y) (af3 z) > rotl :: (a -> b -> c -> d) -> (b -> c -> a -> d) > rotl f y z x = f x y z > rotr :: (a -> b -> c -> d) -> (c -> a -> b -> d) > rotr f z x y = f x y z > rotl4 :: (a -> b -> c -> d -> e) -> (b -> c -> d -> a -> e) > rotl4 f y z t x = f x y z t > rotr4 :: (a -> b -> c -> d -> e) -> (d -> a -> b -> c -> e) > rotr4 f t x y z = f x y z t Some more combinators (only for pairs so far): > twin :: a -> (a,a) > twin x = (x,x) > swap :: (a,b) -> (b,a) > swap (x,y) = (y,x) -- apply a pair of functions to one argument > applyPair :: (a -> b, a -> c) -> a -> (b, c) > applyPair (f, g) x = (f x, g x) -- apply a pair of functions to a pair > cross :: (a -> b, c -> d) -> (a, c) -> (b, d) > cross (f, g) = applyPair (f . fst, g . snd) -- compose a pair of functions onto one function > dotPair :: (a -> b, a -> c) -> (d -> a) -> (d -> b, d -> c) > dotPair (f, g) h = (f . h, g . h) -- compose a pair of functions onto a pair of functions > dotCross :: (a -> b, c -> d) -> (e -> a, f -> c) -> (e -> b, f -> d) > dotCross (f, g) (h, i) = (f . h, g . i) > mapPair :: (a -> b) -> (a, a) -> (b, b) > mapPair = cross . twin > applyFst :: (a -> b) -> (a, c) -> (b, c) > applyFst f = applyPair (f . fst, snd) > applySnd :: (a -> b) -> (c, a) -> (c, b) > applySnd f = applyPair (fst, f . snd) > applyArgs :: (a -> b) -> (c -> d) -> (b -> d -> e) -> (a -> c -> e) > applyArgs af1 af2 f = \x y -> f (af1 x) (af2 y) > betweenFst :: (a -> b -> c) -> (a, d) -> (b, e) -> c > betweenFst = applyArgs fst fst > betweenSnd :: (a -> b -> c) -> (d, a) -> (e, b) -> c > betweenSnd = applyArgs snd snd I find these combinators useful, and probably other people have their own versions - it would be nice to get them standardised, so we all speak the same language. By standardised, I mean a prominent version that will be adopted by users, not necessarily a committee process. Tim

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Re: tuple component functions
by Nils Decker 03 Jan '03

03 Jan '03

ketil(a)ii.uib.no (Ketil Z. Malde) wrote: > I'd like a general 'nth', but of course that would restrict us to > monotyped tuples (e.g., > > nth :: Int -> (a,a,...,a,a) -> a > ) Under [1] you find an interesting proposal for Template Haskell. I don't know, how far it is from beiing implemented, but it would allow $(sel 1 3) x to be replaced by (\x -> case x of (a, b, c) -> a) x at compile time. (example from the paper) Using "program reflection" it should even be possible to detect the size of the tuple at compile time, giving your nth function with a slightly different syntax. Regards Nils Decker [1] http://research.microsoft.com/Users/simonpj/papers/meta-haskell/ -- Nils Decker <ndecker(a)gmx.de>

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ICFP programming contest
by trb＠eastpac.com.au 03 Jan '03

03 Jan '03

Michael Hobbs writes: > Just took a look at the results for the ICFP contest. Am I correct in > assuming that "LA" stands for Lennart Augustsson and that "Si^3" stands > for Simon Marlow, Simon Peyton-Jones, Sigbjorn Finne? Is there a URL for the results ? Tim

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ANNOUNCE: Haskell Wiki resurrected
by Keith Wansbrough 03 Jan '03

03 Jan '03

Hi all... last night I resurrected the Haskell Wiki, http://haskell.org/wiki/wiki This is a set of web pages on Haskell which can be edited and updated by anyone. The intention is to accumulate the combined wisdom of posters to the Haskell lists - if you ever reply to a FAQ with what you think is a particularly good answer, please add it to the Wiki. If you see a FAQ that's been Frequently Asked, just point the poster at the appropriate page on the Wiki. Sadly, the Wiki isn't very stable at the moment. I'm hoping that one day it will be made more stable, but in the meantime, I've taken a snapshot of the state as it was last night, and placed a link to it on the haskell.org front page: http://haskell.org/wikisnapshot/FrontPage.html Note that no updates to the Wiki are ever lost; they're kept in a version control system. So if you see a blank page on the main Wiki where you once spent several hours writing the perfect page, don't worry - it's not lost! Hope this is useful to people! --KW 8-) PS: I'm not officially in charge of the Wiki, John Heron <jheron(a)enteka.com> is; I'm just helping him out at the moment.

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final call for papers icalp 2003
by icalp2003＠TUE.nl 03 Jan '03

03 Jan '03

------------------------------Final Call For Papers---------------------------------------------------- We apologize for the reception of multiple copies of this message. ---------------------------------------------------------------------------- ---------------------------- ICALP2003 Thirtieth International Colloquium on Automata, Languages and Programming Eindhoven, The Netherlands, June 30 - July 4, 2003 The 30th annual meeting of the European Association of Theoretical Computer Science will be held in Eindhoven, The Netherlands, at the Technische Universiteit Eindhoven. As with the journal Theoretical Computer Science (TCS), the scientific program of the Colloquium will be split into two parts: Track A of the meeting will cover Algorithms, Automata, Complexity and Games, while Track B covers Logic, Semantics and Theory of Programming. Topic of interest include but are not limited to: * Track A Algebra & circuits, Approximation algorithms, Combinatorial optimization, Computational biology, Computational geometry, Evolutionary algorithms, Distributed computing, Graph and network algorithms, Molecular computing, Neural networks, Online algorithms, Quantum computing, Randomized algorithms, Routing, Scheduling, Sorting & searching, String algorithms; * Track B Applied logic, Concurrency, Deduction, Hybrid systems, Lambda calculus, Language theory, Logic, Logic of programs, Model checking, Probabilistic systems, Process algebra, Regular Languages, Rewriting, Semantics, Specification & verification, Theorem proving, Theory of programming, Type theory. Submissions Authors are invited to submit a paper presenting original contributions to the theory of computer science. Submissions should consist of: a cover page, with the author's full name, address, fax number, e-mail address, a 100-word abstract, keywords and to which track (A or B) the paper is being submitted. At least one author of an accepted paper should be available to present it at the conference. Simultaneous submission to other conferences with published proceedings is not allowed. Electronic submission of papers through the conference website is the preferred method of submission, see http://www.win.tue.nl/icalp2003/. The conference proceedings will be published by Springer Verlag as a volume in the Lecture Notes in Computer Science series. Hence, authors are encouraged to use the LNCS-style (see http://www.springer.de/comp/lncs/authors.html for instructions). The standard format of an ICALP submission has a textheight of at most 21cm and a textwidth of at most 15cm. The font is 10pt (and for LaTeX-users, the textsize is \normalsize, not \small). A submission has at most 12 pages, possibly followed by an appendix of at most 8 pages. The appendix may contain sketches of long proofs and additional material, but the contribution of the paper must be understandable without reading the appendix. Papers that deviate substantially from this standard format will be rejected. Important Dates * Submissions: January 12, 2003 * Notification: March 18, 2003 * Final version: April 13, 2003 Conference Chair Jos Baeten Technische Universiteit Eindhoven Department of Mathematics and Computing Science P.O. Box 513 5600 MB Eindhoven The Netherlands Program Committee Track A Harry Buhrman, CWI Amsterdam Jens Clausen, DTK Lyngby Martin Dyer, Leeds Lars Engebretsen, KTH Stockholm Uri Feige, Weizmann Philippe Flajolet, INRIA Rocquencourt Kazuo Iwama, Kyoto Elias Koutsoupias, UCLA Jan Karel Lenstra, Georgia Tech, co-chair Stefano Leonardi, Roma Rasmus Pagh, Copenhagen Jean-Eric Pin, CNRS and Paris 7 Uwe Schoening, Ulm Jiri Sgall, CAS Praha Micha Sharir, Tel Aviv Vijay Vazirani, Georgia Tech Ingo Wegener, Dortmund Peter Widmayer, ETH Zuerich Gerhard Woeginger, Twente, co-chair Track B Samson Abramsky, Oxford Eike Best, Oldenburg Manfred Broy, TU Muenchen Philippe Darondeau, INRIA Rennes Rocco De Nicola, Firenze Rob van Glabbeek, Stanford Ursula Goltz, Braunschweig Roberto Gorrieri, Bologna Robert Harper, Carnegie Mellon Holger Hermanns, Twente Kim Larsen, Aalborg Jean-Jacques Levy, INRIA Rocquencourt Flemming Nielson, DTU Lyngby Prakash Panangaden, McGill Joachim Parrow, Uppsala, chair Amir Pnueli, Weizmann Davide Sangiorgi, INRIA Sophia Bernhard Steffen, Dortmund Bjorn Victor, Uppsala Workshops and co-located events In the weekends preceding and following ICALP several workshops that are of interest to the EACTS-community will be held at the conference venue. There will be workshops related to track A as well as workshops related to Track B of ICALP. A preliminary list of satelite events is available on the ICALP 2003 website. In the week preceding ICALP (June 24-27), two more international conferences in computer science are organized by the TU/e: the 4th International Conference on Application and Theory of Petri Nets, ATPN 2003 (http://www.tue.nl/atpn2003/) and the Conference on Business Process Management, BPM 2003 (http://tmitwww.tm.tue.nl/bpm2003/) Contact information ICALP2003 Office Technische Universiteit Eindhoven Department of Mathematics and Computing Science P.O. Box 513 5600MB Eindhoven The Netherlands Telephone: +31 40 2474124 Fax: +31 40 2475361 E-mail: icalp2003(a)tue.nl URL: www.win.tue.nl/icalp2003/

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Questions from New-Old User
by Matthew Donadio 03 Jan '03

03 Jan '03

Hi all, I hope everyone had a nice holiday season. I am picking up a project that I started a few years ago, but for various reasons stopped working on. It was the Libraries for Digital Signal Processing listed in the Numerical Algorithms and Mathematics section on the haskell.org website. I am going to revisit those libraries and expand the scope a little bit to include spectral estimation and some matrix math routines. Anyway, since I haven't done any Haskell in about three years, I am a bit rusty. :) I have one question right now, and would like some advice on another matter. I am sure I will have other questions until the proper section of my brain wakes up. First, I cannot get a function to type. The basic definition is: rxx x k | k >= 0 = sum [ (conjugate (x!k)) * x!(n+k) | k <- [0..(n-1-k)] ] / n | k < 0 = conjugate (rxx x (-k)) where n = snd (bounds x) + 1 This function performs autocorrelation for a complex array, and returns a complex value. The array indexes are integral in the general sense, but could be safely Int. I have tried various combinations of explicit types and numeric type coersion functions without any success. Any help would be appreciated. The second question has to do with the numeric class system. In signal processing and spectral estimation, there are a lot of algorithms that can operate on real and complex data. In most cases, the only difference is the complex versions have conjugates in various places. In the function above, the equivalent real valued version is the same if you either get rid of the conjugate applications, or assume that the conjugate function for real numbers is the identity function. What is the best way to handle this? I don't want to have separate functions for real and complex data, but I'm not sure of the proper way to add conjugate=I to to the class system for non-complex numbers. Thanks. PS, if anyone wants a preview of my LU decomposition module (ie, it could stand a bit more testing), please let me know. -- Matthew Donadio (m.p.donadio(a)ieee.org)

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Question About lists
by Cesar Augusto Acosta Minoli 02 Jan '03

02 Jan '03

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long delayed messages [was Re: tuple component functions]
by Tim Barbour 02 Jan '03

02 Jan '03

Vinicius Callegari writes: [...] > Tim, watch out, your date is in the past. You messages might not be read... Thanks for the warning. The messages were indeed sent in the past, and took an unusually long time to be delivered! Apparently a few messages got queued somewhere by my MTA (perhaps because of a temporary configuration error), and were not sent until today... Coincidentally I am upgrading my Debian installation - presumably this caused the queued mail to get flushed. Sorry about any confusion caused. Tim

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