June 2006 - Haskell - Haskell.org

Re: [Haskell] extensible records using associated types
by Barney Hilken 20 Jun '06

20 Jun '06

The implementation of records using types data N a r = N a r might well be inefficient, and I don't know enough about the workings of the compiler to see whether it could be improved by unboxing and strictness. But the real point of my post was the classes Contains, Lacks and Disjoint which give you extensibility. To give another example, if Haskell had non-extensible records {N1 = x1, ..., Nn = xn} of type {N1 :: a1, ..., Nn :: an} we could use the same technique to make them extensible. Assume we can represent the field names N somehow as values (N :: Constructor N). Then we can define instances of the form instance Contains Nj {N1 :: a1, ..., Nj :: aj, ..., Nn :: an} where type Project Nj {N1 :: a1, ..., Nj :: aj, ..., Nn :: an} = aj type Delete Nj {N1 :: a1, ..., Nj :: aj, ..., Nn :: an} = {N1 :: a1, ..., Nn :: an} project Nj {N1 = x1, ..., Nj = xj, ..., Nn = xn} = xj delete Nj {N1 = x1, ..., Nj = xj, ..., Nn = xn} = {N1 = x1, ..., Nn = xn} instance Lacks M {N1 :: a1, ..., Nn :: an} where type Extend M a {N1 :: a1, ..., Nn :: an} = {M :: a, N1 :: a1, ..., Nn :: an} type extend M x {N1 = x1, ..., Nn = xn} = {M = x, N1 = x1, ..., Nn = xn} instance Disjoint {N1 :: a1, ..., Nn :: an} {M1 :: b1, ..., Mm :: bm} where type Union {N1 :: a1, ..., Nn :: an} {M1 :: b1, ..., Mm :: bm} = {N1 :: a1, ..., Nn :: an, M1 :: b1, ..., Mm :: bm} union {N1 = x1, ..., Nn = xn} {M1 = y1, ..., Mm = ym} = {N1 = x1, ..., Nn = xn, M1 = y1, ..., Mm = ym} Of course, there are a lot of these (exponential in the number of field names!) so you don't really want to generate them all. But exactly the same classes (modulo the definition of Constructor, which should be hidden anyway) give you extensibility, so any code you write will work with either implementation. Barney.

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CPSec workshop extended deadline!
by Stefano Bistarelli 20 Jun '06

20 Jun '06

-------------------------------------------------------------------- EXTENDED DEADLINE: July 1 Call for Papers: CPSec 2006 2nd International Workshop on Applications of Constraint Satisfaction and Programming to Computer Security September 25, 2006 Nantes, France Held in conjunction with 12th International Conference on Principles and Practice of Constraint Programming, CP2006 http://www.sci.unich.it/~bista/organizing/cpsec/ -------------------------------------------------------------------- Constraint Satisfaction and Programming is emerging as an effective and practical approach for solving large complex problems. It offers a significant body of successful techniques for verifying system properties. Recently, researchers have begun using advances in constraint programming and solving to solve security problems, with success. This workshop seeks to act as a catalyst for this emerging area by exploring the challenges and the potential that these techniques may offer when applied to security problems. The use of Constraint Satisfaction and Programming to address security problems is recent, and it has already produced a number of novel solutions and insights. For example, constraints have been successfully used in the the analysis of security protocols, the development of access control models and mechanisms, firewall configuration and secure system configuration in general. Workshop topics include (but are not limited to): Access Control Database Security Security Trade-offs Information Flow Integrity Configuration Management Security Models Reliability Security Protocols Intrusion Detection Applications Risk Analysis Trust Software Security Trust Negotiation Submissions The workshop aim is to provide a forum where researchers currently working in the area of security and constraints can discuss their most recent ideas and developments and think together about the most promising new directions. Therefore we encourage the presentation of work in progress or on specialized aspects of the area. Papers that bridge the gap between theory and practice are especially welcome. Prospective attendees can submit a paper, which can be up to 15 pages in length. We encourage authors to submit papers electronically in postscript or pdf format. Papers should be formatted using the Lecture Notes in Computer Science (LNCS) style. At least one author of each accepted submission must attend the workshop, and all participants must pay the workshop fee. Please send your submissions by email to stefano.bistarelli(a)iit.cnr.it using the subject line "cpsec-2006 Workshop Submission". Important Dates Paper Submission deadline: July 1 (extended deadline) Notification of acceptance: July 22th Early registration deadline: August 1st Camera-ready version deadline: August 5th Workshop Date: September 25, 2006. Workshop Organizers: Giampaolo Bella (Universit`a di Catania, Italy) Stefano Bistarelli (Università degli studi "G. D'Annunzio" di Chieti-Pescara & C.N.R. Pisa, Italy) Simon Foley (University College Cork, Ireland) Fred Spiessens (University College Cork, Ireland) Program Committee: Giampaolo Bella, Catania Fabio Martinelli, CNR Stefano Bistarelli, Pescara and CNR Barry O'Sullivan, Cork Yannick Chevalier, IRIT Justin Pearson, Uppsala Giorgio Delzanno, Genova Michael Rusinowich, LORIA Alessandra Di Pierro, Pisa Fred Spiessens, Cork Fabio Fioravanti, Pescara, Vitaly Shmatikov, Texas Simon Foley, Cork Frank D. Valencia, CNRS John Herbert, Cork Luca Vigano, Zurich Ralf Küsters, Kiel Duminda Wijesekera, GMU Herbert Wiklicky, Imperial

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Streams and ArrayRef librraies
by Bulat Ziganshin 18 Jun '06

18 Jun '06

Hello haskell, thanks to John Peterson, i finally relocated my libs to the haskell.org. Installation procedure was also simplified. Streams 0.1e library: Documentation: http://haskell.org/haskellwiki/Library/Streams Download: http://www.haskell.org/library/Streams.tar.gz Installation: run "make install" ArrayRef 0.1 library: Documentation: http://haskell.org/haskellwiki/Library/ArrayRef Download: http://www.haskell.org/library/ArrayRef.tar.gz Installation: run "make install" -- Best regards, Bulat mailto:Bulat.Ziganshin@gmail.com

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Where are all the Haskell show-offs?
by Ronnie Holm 17 Jun '06

17 Jun '06

Walking down Lisp Street and Ruby Road, I've noticed how they've got screencasts showing off various parts of their neighbourhood: http://www.rubyonrails.org/screencasts, http://www.cl-user.net/asp/ftyG2/sdataQG7GC09G$um5DQ3PQRpX8yBX8yBXnMq=/sdat… http://homepage.mac.com/svc/LispMovies/index.html. It would be fun to see how and what kind of environments people use for Haskell development. And really cool to have a couple of videos on haskell.org as a appetizer, and as a sign that Haskell Avenue isn't at all that bad a place. What do you think? Ronnie __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com

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A road for Haskell into the kernel of a full-fledged OS
by oleg＠pobox.com 16 Jun '06

16 Jun '06

I'm attending a USENIX conference and just had a nice talk with Andrew Tanenbaum. As some may know, he's working on the new version of Minix, Minix3. It is actually working, now with the X windows interface: http://www.minix3.org Andrew Tanenbaum said that it is important for a language like OCaml or Haskell to get more visibility among the OS developers; and Minix offers a very good way to do that. Minix3 is based on micro-kernel; all of the OS services (memory manager, file system, all the drivers, etc.) run as regular processes communicating through a well-defined protocol. It is irreleveant what language these services are written in, so long as they obey the protocol. Some of Andrew Tanenbaum's students are interested in re-writing some of Minix3 OS services (like device drivers or file systems, currently written in C) in Ocaml and Cyclone. He is interested in the outcome. Haskell is a good candidate too. It is quite instructive to compare a device driver in Haskell with the original C driver -- it terms of length, speed, time to write, number of bugs, etc. Andrew Tananbaum suggested that the terminal driver may be the best start, because it is quite stand-alone, small and its protocol is simple. With Minix, we can replace one kernel service of the full-fledged, working OS with the one written in Haskell -- and immediately see how it all works. If it doesn't, the rest of OS still works and so we can unload the faulty service and load another implementation. Minix3 does indeed offer an easy road to the OS kernel for a language other than C. I said that there may be quite a bit of interest in Haskell community in such a project. I wonder if I'm right...

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Streams 0.1e released
by Bulat Ziganshin 16 Jun '06

16 Jun '06

Hello I released Streams library version 0.1e. Changes are: - Fixed bug: "openFD name WriteMode" don't truncated files on unixes * Full library now released under BSD3 license, thanks to John Goerzen + Now cabalized, thanks to Jeremy Shaw Download: http://freearc.narod.ru/Streams.tar.gz Docs: http://haskell.org/haskellwiki/Library/Streams btw, my cabal file contain line: Build-Depends: base, Win32, template-haskell if i correctly understand, this will not work on unix systems, while without Win32 package program can't be compiled on my windows box. what i can do here? only provide two separate cabal files - one for unix, one for windows and give to user text instructions about manual renaming of appropriate file? -- Best regards, Bulat mailto:Bulat.Ziganshin@gmail.com

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Haskell Weekly News: June 16, 2006
by dons＠cse.unsw.edu.au 16 Jun '06

16 Jun '06

Welcome to issue 37 of HWN, a weekly newsletter covering developments in the Haskell community. Each Monday, new editions are posted to [1]the Haskell mailing list as well as to [2]the Haskell Sequence and [3]Planet Haskell. [4]RSS is also available, and headlines appear on [5]haskell.org. This edition -- better late than never -- covers another madly busy 2 weeks for the Haskell community. 1. http://www.haskell.org/mailman/listinfo/haskell 2. http://sequence.complete.org/ 3. http://planet.haskell.org/ 4. http://sequence.complete.org/node/feed 5. http://haskell.org/ Announcements * Google Summer of Code. The Haskell.org team [6]announced that nine Haskell projects have been selected to receive funding to the value of $45k under Google's 2006 [7]Summer of Code program. A wide range of projects will be worked on, contributing to the community important tools and libraries. The students have until August 21 to complete their projects, and receive their grants. Details of the accepted projects can be found [8]here 6. http://www.haskell.org/pipermail/haskell/2006-May/017999.html 7. http://code.google.com/soc 8. http://code.google.com/soc/haskell/about.html * Haskell Communities & Activities Report. Andres Loeh [9]published the 10th edition of the Haskell Communities and Activities Report (HCAR). If you haven't encountered the Haskell Communities and Activities Reports before, you may like to know that the first of these reports was published in November 2001. Their goal is to improve the communication between the increasingly diverse groups, projects and individuals working on, with, or inspired by Haskell. Read the 10th edition [10]here. 9. http://www.haskell.org/pipermail/haskell/2006-June/018071.html 10. http://www.haskell.org/communities/ * Would you like a job working on GHC?. Simon Peyton-Jones [11]announced that GHC HQ is looking for support engineer. The Glasgow Haskell Compiler (GHC) is now being used by so many people, on so many platforms, that GHC HQ has been struggling to keep up. In particular, the candidate should be someone who is enthusiastic about Haskell, and fired up about the prospect of becoming a GHC expert. 11. http://www.haskell.org/pipermail/haskell/2006-June/018068.html * Shellac and Lambda Shell 0.3. Robert Dockins [12]announced the simultaneous release of Shellac 0.3 and Lambda Shell 0.3. Shellac is a library for creating read-eval-print style shells. It makes binding to feature-rich shell packages (ie, readline) easier. Lambda shell is full-featured shell environment for evaluating terms of the pure untyped lambda calculus and a showcase/tutorial for Shellac's features. 12. http://www.haskell.org/pipermail/haskell/2006-May/018041.html * darcs-graph. Don Stewart released [13]darcs-graph, a tool for generating graphs of commit activity for darcs repositories. 13. http://www.cse.unsw.edu.au/~dons/darcs-graph.html * VersionTool 1.0. Manuel Chakravarty [14]announced version 1.0 of [15]VersionTool, a small utility that: + extracts version information from Cabal files, + maintains version tags in darcs, + computes patch levels by querying darcs, + extracts the current context from darcs, and + adds all this information to a source file 14. http://www.haskell.org/pipermail/haskell/2006-June/018063.html 15. http://www.cse.unsw.edu.au/~chak/haskell/VersionTool/ * Streams 0.1e. Bulat Ziganshin [16]released Streams library version 0.1e. Now cabalised and BSD-ified. 16. http://www.haskell.org/pipermail/haskell/2006-June/018063.html * Hitchhikers guide to Haskell - chapter 5. Dmitry Astapov [17]announced that chapter 5 of his online tutorial, the Hitchhikers guide to Haskell, is available. Changes include: It's bigger. It's better. It now comes with source code included. 17. http://www.haskell.org/pipermail/haskell-cafe/2006-June/015966.html * Haskell Shell (HSH) 0.1.0. John Goerzen [18]released version 0.1.0 of HSH, the Haskell shell. Things are still very preliminary in many ways, but this version already lets you: + Run commands + Pipe things between commands + Pipe command input/output into and out of pure Haskell functions + Pure Haskell functions are as much a first-class citizen as is grep or cat 18. http://www.haskell.org/pipermail/haskell/2006-June/018059.html * Edison 1.2. Robert Dockins [19]released the final, stable release of Edison 1.2. Edison is a library of efficient, purely-functional data structures for Haskell. 19. http://www.haskell.org/pipermail/haskell/2006-June/018050.html * Arrays & References Library 0.1. Bulat Ziganshin [20]announced version 0.1of his arrays and references library. Featuring: + Unboxed references in IO and ST + Monad-independent interfaces to boxed and unboxed references + Syntax sugar to make using of mutable objects easier (=:, +=, -=,..) and more. 20. http://www.haskell.org/pipermail/haskell/2006-June/018044.html * Kamiariduki Shelarcy [21]released Kamiariduki - a system to judge your derivative work's purpose and license is valid with Ceative Commons License Works. 21. http://www.haskell.org/pipermail/haskell/2006-June/018043.html * lambdabot 4.0. Don Stewart [22]announced the release of version 4.0 of the venerable Haskell IRC bot, lambdabot. lambdabot is a stable, feature rich IRC bot based on a plugin framework. lambdabot 4.0 comes with a suite of more than 50 plugins, and many new features. 22. http://www.haskell.org/pipermail/haskell/2006-June/018077.html Haskell' This section covers activity on [23]Haskell' standardisation process. * [24]Regarding Class Aliases. 23. http://hackage.haskell.org/trac/haskell-prime 24. http://www.haskell.org//pipermail/haskell-prime/2006-May/001568.html Discussion * A road for Haskell into OS kernels. Oleg Kisleyov [25]sparked a bit of a discussion about Haskell's use in OS projects, after similar remarks from Andrew Tanenbaum at USENIX. 25. http://www.haskell.org/pipermail/haskell/2006-June/018045.html Contributing to HWN You can help us create new editions of this newsletter. Please see the [26]contributing information, send stories to dons -at- cse.unsw.edu.au. The darcs repository is available at: darcs get http://www.cse.unsw.edu.au/~dons/code/hwn 26. http://haskell.org/haskellwiki/HWN

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ANNOUNCE: Haskell Communities & Activities Report (10th ed., June 2006)
by Andres Loeh 15 Jun '06

15 Jun '06

On behalf of the many, many contributors, I am pleased to announce that the Haskell Communities and Activities Report (10th edition, June 2006) http://www.haskell.org/communities/ is now available from the Haskell Communities home page in several formats: PDF, for screenreading as well as printing, HTML, for those of you who prefer not to deal with plugins or external viewers, and PostScript, for those of you who have nice quick printers that do not grok PDF. Many thanks go to all the people that contributed to this report, both directly, by sending in descriptions, and indirectly, by doing all the interesting things that are reported. I hope you will find it as interesting a read as we did. If you haven't encountered the Haskell Communities and Activities Reports before, you may like to know that the first of these reports was published in November 2001. Their goal is to improve the communication between the increasingly diverse groups, projects and individuals working on, with, or inspired by Haskell. The idea behind these reports is simple: Every six months, a call goes out to all of you enjoying Haskell to contribute brief summaries of your own area of work. Many of you respond (eagerly, unprompted, and well in time for the actual deadline ;) ) to the call. The editor collects all the contributions into a single report and feeds that back to the community. When we try for the next update, six months from now, you might want to report on your own work, project, research area or group as well. So, please put the following into your diaries now: ---------------------------------------- End of October 2006: target deadline for contributions to the November 2006 edition of the HC&A Report ---------------------------------------- Unfortunately, many Haskellers working on interesting projects are so busy with their work that they seem to have lost the time to follow the Haskell related mailing lists and newsgroups, and have trouble even finding time to report on their work. If you are a member, user or friend of a project so burdened, please find someone willing to make time to report and ask them to `register' with the editor for a simple e-mail reminder in the middle of October (you could point me to them as well, and we can then politely ask if they want to contribute, but it might work better if you do the initial asking). Of course, they will still have to find the ten to fifteen minutes to draw up their report, but maybe we can increase our coverage of all that is going on in the community. Feel free to circulate this announcement further in order to reach people who might otherwise not see it. Enjoy! Andres Loeh <hcar at haskell.org> -- Haskell Communities and Activities Report (http://haskell.org/communities)

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CUFP: Call for Contributions
by Kathleen Fisher 15 Jun '06

15 Jun '06

[ Apologies for multiple postings; please forward to potentially interested parties ] CUFP 2006 THE THIRD COMMERCIAL USERS OF FUNCTIONAL PROGRAMMING WORKSHOP "Functional programming as a means, not an end" Portland, Oregon, USA September 21st 2006 Co-located with ICFP Functional languages have been under academic development for over 25 years, and are still proving to be very fertile ground for programming language research. Consequently, most of the development focus of these languages is driven by academic and theoretical questions. More recently, however, functional languages have been very successfully used in commercial, industrial, and government settings, as well as in the open-source community. In these settings, the advantages of functional languages have provided dramatic leverage. The goal of CUFP is to act as a voice for commercial users of functional programming languages and technology. It aims to help functional programming become increasingly viable as a technology for use in the commercial, industrial, governmental, and open-source space by providing a forum for FP professionals to share their experiences and ideas, whether business, management or engineering. It also aims to enable the formation and strengthening of relationships and alliances that further the commercial use of functional languages. Providing user feedback to language designers and implementors is not a primary goal of the workshop, though it will be welcome if it occurs. Program plans ------------- The meeting will last a full day, with a mix of invited and submitted presentations, plus discussion sessions. Topics will range over a wide area, including: * Case studies both of successful and unsuccessful uses of functional programming; * Business opportunities and risks from using functional languages; * Enablers for functional language use in a commercial setting; * Barriers to the adoption of functional languages, and * Mitigation strategies for overcoming limitations of FP. There will be no published proceedings, as the meeting is intended to be more a discussion forum than a technical interchange. See http://www.galois.com/cufp/ for more information, including last year's schedule and a report describing a previous CUFP workshop. This year's schedule will also be available there soon. Submissions ----------- Submissions by prospective speakers or suggestions for speakers are welcome! Just send an e-mail to kfisher at research.att.com with an outline of what you'd like to talk about or what you think your suggestee should give a talk about. Program Committee ----------------- Andy Adams-Moran. adams-moran at galois.com (Co-Chair) Mike Ashley. mashley at beckman.com Matthias Felleisen. matthias at ccs.neu.edu Kathleen Fisher. kfisher at research.att.com (Chair) Jim Grundy. jim_grundy at ichips.intel.com John Hughes. rjmh at cs.chalmers.se Stephen Weeks. sweeks at sweeks.com Ulf Wiger. ulf.wiger at ericsson.com

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CFP: Partial Evaluation and Program Manipulation (PEPM'07)
by Eelco Visser 15 Jun '06

15 Jun '06

---------------------------------------------------------------------- Call For Papers ACM SIGPLAN 2007 Workshop on PARTIAL EVALUATION AND PROGRAM MANIPULATION (PEPM'07) Nice, France January 15-16, 2007 (Co-located with POPL 2007) http://www.program-transformation.org/PEPM07 ---------------------------------------------------------------------- The PEPM Symposium/Workshop series aims to bring together researchers and practitioners working in the areas of program manipulation, partial evaluation, and program generation. PEPM focuses on techniques, theory, tools, and applications of analysis and manipulation of programs. The 2007 PEPM workshop will be based on a broad interpretation of semantics-based program manipulation and continue last year's successful effort to expand the scope of PEPM significantly beyond the traditionally covered areas of partial evaluation and specialization and include practical applications of program transformations such as refactoring tools, and practical implementation techniques such as rule- based transformation systems. In addition, the scope of PEPM covers manipulation and transformations of program and system representations such as structural and semantic models that occur in the context of model-driven development. In order to reach out to practitioners, a separate category of tool demonstration papers will be solicited. ---------------------------------------------------------------------- Topics of interest for PEPM'07 include, but are not limited to: + Program and model manipulation techniques such as transformations driven by rules, patterns, or analyses, partial evaluation, specialization, slicing, symbolic execution, refactoring, aspect weaving, decompilation, and obfuscation. + Program analysis techniques that are used to drive program/model manipulation such as abstract interpretation, static analysis, binding-time analysis, dynamic analysis, constraint solving, and type systems. + Analysis and transformation for programs/models with advanced features such as objects, generics, ownership types, aspects, reflection, XML type systems, component frameworks, and middleware. + Techniques that treat programs/models as data objects including meta-programming, generative programming, staged computation, and model-driven program generation and transformation. + Application of the above techniques including experimental studies, engineering needed for scalability, and benchmarking. Examples of application domains include legacy program understanding and transformation, domain-specific language implementations, scientific computing, middleware frameworks and infrastructure needed for distributed and web-based applications, resource-limited computation, and security. We especially encourage papers that break new ground including descriptions of how program/model manipulation tools can be integrated into realistic software development processes, descriptions of robust tools capable of effectively handling realistic applications, and new areas of application such as rapidly evolving systems, distributed and web-based programming including middleware manipulation, model-driven development, and on-the-fly program adaptation driven by run-time or statistical analysis. ---------------------------------------------------------------------- Submission Categories and Guidelines Regular research papers must not exceed 10 pages in ACM Proceedings style. Tool demonstration papers must not exceed 4 pages in ACM Proceedings style, and authors will be expected to present a live demonstration of the described tool at the workshop. Suggested topics, evaluation criteria, and writing guidelines for both research tool demonstration papers will be made available on the PEPM'07 web site. Papers should be submitted electronically via the workshop web site. The workshop proceedings will be published in the ACM Digital Library and selected papers will be invited for a journal special issue dedicated to PEPM'07. ---------------------------------------------------------------------- Important Dates + Abstracts due: October 18, 2006 + Submission: October 20, 2006 + Notification: December 1, 2006 + Camera-ready: December 18, 2006 + Workshop: January 15-16, 2007 ----------------------------------------------------------------------- Program Chairs * G. Ramalingam (IBM Research, Bangalore) * Eelco Visser (Utrecht University, The Netherlands) Program Committee Members * Ras Bodik (University of California, Berkeley, USA) * Albert Cohen (INRIA, France) * Jim Cordy (Queen's University, Canada) * Martin Erwig (Oregon State University, USA) * Bernd Fischer (University of Southampton, UK) * John Hatcliff (Kansas State University, USA) * Jan Heering (CWI, The Netherlands) * Dan Grossman (University of Washington, USA) * Annie Liu (State University of New York at Stony Brook, USA) * Jacques Noyé (École des Mines de Nantes/INRIA, France) * German Puebla (Technical University of Madrid, Spain) * Peter Sestoft (Royal Veterinary and Agricultural University, Denmark) * Yannis Smaragdakis (Georgia Tech, Atlanta, USA) * Walid Taha (Rice University, Houston, USA) -----------------------------------------------------------------------

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