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Re: Scheme in Haskell?
by David Feuer 19 Feb '02

19 Feb '02

I would be very surprised if no one had written a Scheme interpreter in Haskell. It is an obvious project for an undergrad like myself. Good practice playing with monads and such. I'm planning to try it at some point. Query: Aside from learning about Scheme and about writing interpreters, what purpose would this serve? The natural language for writing Scheme interpreters is Scheme, and the language that would probably be desired for efficiency is C. David Feuer

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Problems with Happy and GHC
by faires＠elogica.com.br 18 Feb '02

18 Feb '02

Hello, I am trying to make a parse to Haskell and I am using Happy. I used this parser and it generated a haskell file parser.hs. When I try to compile it, it requests a module called preladdr . How can I obtain this module?? Thanks, Fernando

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Composition Monad
by Andre W B Furtado 18 Feb '02

18 Feb '02

Roughly speaking, I'm in need of a monad (say MyIO) that interprets the following code >f :: MyIO () >f = do > action1 > action2 > action3 > ... > return () as applying action1 to g, then action2 to the SAME g (not the result of action1) and so on... Of course, this "g" will be specified when starting the monad (something like "runMyIO g"). Does this "composition monad" already exist? If no, can anyone give me some hints to create my own? Thanks a lot -- Andre

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Extended deadline: Workshop on Generative Programming (GP2002)
by Joost Visser 18 Feb '02

18 Feb '02

------------------------------------------------ Workshop on Generative Programming 2002 (GP2002) ------------------------------------------------ Austin (Texas), April 15, 2002 http://www.cwi.nl/GP2002 (extended) Submission deadline: February 28, 2002 Satelite of the 7th International Conference on Software Reuse (ICSR7) Background ---------- The goal of generative programming is to replace manual search, adaptation, and assembly of components with the automatic generation of needed components on demand. Generative technology has been in practical use for decades (e.g., compiler development, application generation, automatic configuration management, preprocessing, meta-programming). However, developing new domain-specific languages (DSLs), application generators, and component generators has been extremely hard, as it requires being knowledgeable and experienced both in language design and compiler development. Recent developments such as XML technologies and template meta-programming revived the interest in generative programming by making it more accessible to developers. Objectives ---------- The workshop aims to bring together practitioners, researchers, academics, and students to discuss the state-of-the-art of generative techniques and their impact on software reuse. The goal is to share experience, consolidate successful techniques, and identify the most promising application areas and open issues for future work. Topics of interest ------------------ * impact of generative techniques on component-based development and software reuse. * assessing risks and benefits of deploying generative techniques; * maintenance of generators. * reuse of generic components, generators, generator components, configuration languages, and other generative programming assets across boundaries of projects and/or organizations. * styles of generative programming (application generators, generators based on XML technologies, template languages (e.g., JSP), template meta-programming, transformational systems, intentional languages, aspects, subjects, etc), particularly their uses and limitations. * generation of code artifacts, such as application logic, UIs, database schemas, and middleware integration. * generation of non-code artifacts such as test cases, documentation, tutorials, and help systems. * capturing configuration knowledge, for example, in DSLs, and extensible languages. * influence on software architecture (e.g., building and customizing frameworks and applying patterns). * testing generic and generative models. * industrial applications of generative technology. Submissions ----------- Potential participants are asked to submit a two-page position paper detailing their experience with generative techniques, their perspective on one or more of the above topics, and their planned contribution to the workshop. We seek concrete case studies, and potential topics of discussion in order to ground the workshop in real-world issues. Please mail your submission (in PDF or PS) to Joost Visser (Joost.Visser(a)cwi.nl) by February 28, 2002. Important Dates --------------- * Workshop submission deadline: February 28, 2002 * Notification of acceptance: March 14, 2002 * Workshop at ICSR7: April 15, 2002 Workshop format --------------- The workshop will aim to foster discussion and interaction rather than presentations. Presentations will serve to introduce a case study, provoke discussion by presenting a controversial point of view, or introduce new points of view. However, all participants will be given a chance to make a short presentation. All accepted position papers will be published on the workshop page prior to the workshop and the participants will be asked to read the papers prior to the workshop. Tentative schedule ------------------ Morning session: * Introductory talk on GP by the organizers. * First block of presentations, each consisting of a 10 minute talk by the author of an accepted paper followed by 5 minutes of answering questions from the audience. The questions are meant only for clarification; discussion is postponed to the afternoon sessions. * Second block of presentations. Afternoon session: * Short invited talk. * Pro-and-contra session where each paper is discussed by two volunteers that defend opposing views. The audience is invited to provide additional arguments. * Open discussion session aimed at identifying and summarizing open issues and topics for future work. Dissemination of results ------------------------ The results of the workshop will be summarized in a workshop report. The workshop report and the position papers will be available form the workshop website after the workshop. Related events -------------- Past incarnations of this workshop: 1. Generative Programming at ECOOP in Budapest (June 2001). http://www.generative-programming.org/ecoop-workshop.html 2. Generative Programming at OOPSLA in Tampa (October 2001). http://www.generative-programming.org/oopsla01-workshop.html Conferences and workshops on related topics: 1. Workshop on Generative Techniques for Product Lines. Held at the First Software-Product Line Conference (SPCL1) in Denver (August 2000) and at ICSE in Toronto (May 2001). 2. International Conference on Generative and Component-Based Software Engineering (GCSE). Held in Erfurt, Germany (September 1999, October 2000, September 2001) Organizing committee -------------------- Joost Visser - CWI, The Netherlands, Joost.Visser(a)cwi.nl Merijn de Jonge - CWI, The Netherlands Ted Biggerstaff - USA Craig Cleaveland - independent software consultant, USA Krzysztof Czarnecki - DaimlerChrysler Research, Germany Andre van der Hoek - University of California, USA Stan Jarzabek - National University of Singapore, Singapore Shriram Krishnamurthi - Brown University, USA

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PPDP 2002 - Call for papers --> March 21
by Claude Kirchner 18 Feb '02

18 Feb '02

PPDP 2002 - Call for papers March 21, 2002 submission deadline http://ppdp2002.cs.brown.edu Fourth International Conference on Principles and Practice of Declarative Programming 6-8 October, Pittsburgh, USA as part of PLI 2002 (http://pli2002.cs.brown.edu) Invited speakers: Neil Jones (University of Copenhagen) Catuscia Palamidessi (The Pennsylvania State University) Janos Sztipanovits (Vanderbilt University ) Important dates March 21, 2002 submission FIRM deadline May 30, 2002 acceptance decisions June 30, 2002 Camera-ready copies October 6-8, 2002 Conference Submission web site: http://ppdp-2002.loria.fr Conference Chair: Frank Pfenning, CMU, USA Program Chair: Claude Kirchner, LORIA and INRIA 615, rue du Jardin Botanique, BP 101 54602 Villers-lès-Nancy, France Claude.Kirchner(a)loria.fr Program Committee: Hassan Ait Kaci: ILOG, France Olivier Danvy: BRICS, University of Aarhus, Denmark Mariangiola Dezani: Universita di Torino, Italy Francois Fages: INRIA, France Fergus Henderson: The University of Melbourne, Australia Manuel Hermenegildo: University of Madrid, Spain Andrew Gordon: Microsoft Research, UK Amy Felty: University of Ottawa, Canada Claude Kirchner: LORIA & INRIA, France Paul Klint: CWI, The Netherlands Michael Maher: Griffith University, Australia and Loyola University Chicago, USA Dale Miller: The Pennsylvania State University, USA Roberto Nieuwenhuis: University of Barcelona, Spain Frank Pfenning: CMU, USA Francesca Rossi: University of Padova, Italy Scope of the Conference PPDP aims to stimulate research on the use of declarative methods in programming and on the design, implementation and application of programming languages that support such methods. Topics of interest include any aspect related to understanding, integrating and extending programming paradigms such as those for logic, functional, constraint, probabilistic, rule and object-oriented programming; concurrent extensions and mobile computing; type theory; support for modularity; use of logical methods in the design of program development tools; program analysis and verification; abstract interpretation; development of implementation methods; application of the relevant paradigms and associated methods in industry and education. This list is not exhaustive: submissions related to new and interesting ideas relating broadly to declarative programming are encouraged. The technical program of the conference will combine presentations of the accepted papers and system descriptions with invited talks and advanced tutorials. Previous PPDP meetings were held in Paris (1999), Montreal (2000), Firenze (2001). Topics of Interest Logic and Constraint Programming; Rule Programming; Object-Oriented Programming; Concurrent Programming; Mobile Computing; Specification Languages and Methods; Type and Module Systems; Program Logics and Verification; Program Analysis and Transformation; Abstract Machines and Compilation Methods; Parallel and Distributed Implementations; Programming Environments; Applications of Declarative Programming; Implementation Techniques; Logical and Semantical Aspects of Declarative Programming; Declarative and probabilistic programming. Paper Submissions Submissions must be received on or before March 21, 2002 (this is a HARD deadline) and must describe original, previously unpublished work that has not been simultaneously submitted for publication elsewhere. They must be written in English and, in case the work is accepted for presentation and publication, one of the author must attend the conference to present it. Submissions must contain a clearly delineated part intended for the proceedings not exceeding 12 pages and 9 pt (for a full description see the ACM conference format at http://www.acm.org/sigplan/conferences/author-info) and must have a cover page with an abstract of up to 200 words, keywords, postal and electronic mailing addresses, and phone and fax numbers of the corresponding author. Additional material for possible consideration by reviewers may be included in the form of appendices. Submitted papers can be either: Regular papers that will be judged in particular on originality, correctness and significance, or System descriptions that will be judged in particular on usefulness and design, originality of system design, implementation or application. They must contain a link to a working system. All submissions are to be electronic unless specifically approved by the Program Chair. Submissions in PostScript or PDF formats should be submitted via the conference management system as described on the web site. Authors will be notified of acceptance decisions by May 30, 2002 Camera-ready copies of the accepted papers must be received by June 30, 2002. Proceedings will be published by ACM Press. Authors of accepted papers will be required to sign the ACM copyright form, which will be made accessible from this site. Conference Venue and Related Events PPDP 2002 is part of a federation of colloquia known as Principles, Logics and Implementations of high-level programming languages (PLI 2002) which includes the ACM SIGPLAN International Conference on Functional Programming (ICFP 2002) and the first ACM SIGPLAN Conference on Generators and Components (GCSE/SAIG'02) . The colloquia and affiliated workshops will run from October 4 to October 8, 2002 and will be held in Pittsburgh, USA. Details about the affiliated conferences and workshops will appear at the URL http://pli2002.cs.brown.edu/. Sponsorship PPDP 2002 is sponsored by ACM SIGPLAN. ----------------------------------------------------------------

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Re: a universal printer for Haskell?
by Ashley Yakeley 18 Feb '02

18 Feb '02

At 2002-02-18 03:11, Bernard James POPE wrote: >The compiler is required to generate instances of Reify for all types >in the program (instances for built in types are hand-coded in a Standard >Library). This is reflection! I'd rather not have Haskell contaminated with such things; I know Generics are just as bad, but I'm hoping they won't catch on. Speaking of which, can you not do this sort of thing with Generics anyway? -- Ashley Yakeley, Seattle WA

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Re: Composition Monad
by Ashley Yakeley 18 Feb '02

18 Feb '02

At 2002-02-17 18:52, Tom Pledger wrote: >I think it's called a reader monad or an environment monad. Here's a >fairly simple version: I made one here: <http://cvs.sourceforge.net/cgi-bin/viewcvs.cgi/*checkout*/jvm-bridge/sourc e/Haskell/ContextMonad.hs?rev=HEAD&content-type=text/plain> -- Ashley Yakeley, Seattle WA

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RE: ideas for compiler project
by Simon Peyton-Jones 17 Feb '02

17 Feb '02

Lots of people have observed that Haskell might be a good "scripting language" for numerical computation. In complicated numerical applications, the program may spend most of its time in (say) matrix multiply, which constitutes a tiny fraction of the code for the application. So write the bulk of the application in Haskell (where the logic is complex but the performance doesn't matter) and then link to a C or Fortran library to do the small part that is really compute intensive. More concretly, suppose you built an FFI interface to BLAS or some readily available numerical library, and then demonstrated the utility of the resulting beast by writing some non-trivial numerical application in it. You'd need to find a "real" application though. The classical "kernels" (matrix multiply, inversion etc) are precisely the things you may not want to do in Haskell. Simon | -----Original Message----- | From: Hal Daume III [mailto:hdaume@ISI.EDU] | Sent: 22 January 2002 22:00 | To: Haskell Mailing List | Subject: ideas for compiler project | | | Hi All, | | I'm currently taking a class in compiler optimization for | high performance computing (i.e., parallel architectures, | including VLIW, FPGA, multimedia extension architectures, | systems-on-a-chip, etc). It's the second of two graduate | level compiler courses, and it purely project based. And the | project is of our choosing. | | The professor has made some suggested projects, which I could | do, but none of them are really FP specific. I'm curious if | anyone has any ideas of a project I could do. I'm looking | for something that's open, yet | constrained, etc (standard semester-long-project-course | stuff), hopefully having to do with optimizations | specifically for FPLs, or at least ones that would benefit them. | | I'm open to all ideas... | | - Hal | | -- | Hal Daume III | | "Computer science is no more about computers | hdaume(a)isi.edu | than astronomy is about telescopes." -Dijkstra | www.isi.edu/~hdaume | | | _______________________________________________ | Haskell mailing list | Haskell(a)haskell.org http://www.haskell.org/mailman/listinfo/haskell |

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haskell & sparse matrices
by Hal Daume III 17 Feb '02

17 Feb '02

Are there any Haskell libs for dealing with sparse matrices (or even just libraries for writing to and reading from a standard format, say, harwell boeing? - Hal -- Hal Daume III "Computer science is no more about computers | hdaume(a)isi.edu than astronomy is about telescopes." -Dijkstra | www.isi.edu/~hdaume

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allowing non-sequentiality in IO
by Hal Daume III 16 Feb '02

16 Feb '02

Hi, In general, when working in the IO monad, it guarentees that the order of operations is the same as how it's specified. For instance: main = do putStrLn "hi" putStrLn "bye" could not possibly output "bye" before "hi". What if I don't care about this? Is there any way to tell the compiler that it is free to reorder these? The reason I ask is that I'm generating a FSM description file and it doesn't matter which order I list the transitions in. I'm curious whether I could get the program to run any faster if I don't care about order. The only thing I can think of would be to define a new nonsequential IO monad that basically used unsafePerformIO to do the computations. So it would basically transform the above from to: main = unsafePerformIO (putStrLn "hi") `seq` unsafePerformIO (putStrLn "bye") and then order wouldn't be guarentee, right? - Hal -- Hal Daume III "Computer science is no more about computers | hdaume(a)isi.edu than astronomy is about telescopes." -Dijkstra | www.isi.edu/~hdaume

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