October 2006 - Haskell

ASCII higher than 127
by Andreas Marth 17 Oct '06

17 Oct '06

How was that with Haskell and Unicode??? While up to ghc-6.4.2 the following function worked it now doesn't compile: isSpezGermanChar :: Char -> Bool isSpezGermanChar 'ä' = True isSpezGermanChar 'ö' = True isSpezGermanChar 'ü' = True isSpezGermanChar 'Ä' = True isSpezGermanChar 'Ö' = True isSpezGermanChar 'Ü' = True isSpezGermanChar 'ß' = True isSpezGermanChar _ = False (For those of you who will only read garbage it are/were some letters from the german alphabet.) I hoped we move forward to easier internationalization. Any ideas what to do now? (I would like to keep the code readable and not use '\220' and so on. Thanks, Andreas

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GTTSE 2007 --- First call for participation (02-07 July 2007)
by Joost Visser 16 Oct '06

16 Oct '06

GTTSE 2007, 02-07 July, 2007, Braga, Portugal 2nd International Summer School on Generative and Transformational Techniques in Software Engineering http://www.di.uminho.pt/GTTSE2007 SCOPE AND FORMAT The summer school brings together PhD students, lecturers, technology presenters, as well as other researchers and practitioners who are interested in the generation and the transformation of programs, data, models, meta-models, and documentation. This concerns many areas of software engineering: software reverse and re-engineering, model-driven approaches, automated software engineering, generic language technology, to name a few. These areas differ with regard to the specific sorts of meta-models (or grammars, schemas, formats etc.) that underlie the involved artifacts, and with regard to the specific techniques that are employed for the generation and the transformation of the artifacts. The tutorials are given by renowned representatives of complementary approaches and problem domains. Each tutorial combines foundations, methods, examples, and tool support. The program of the summer school also features invited technology presentations, which present setups for generative and transformational techniques. These presentations complement each other in terms of the chosen application domains, case studies, and the underlying concepts. The program of the school also features a participants workshop. All summer school material will be collected in proceedings that are handed out to the participants. Formal proceedings will be compiled after the summer school, where all contributions are subjected to additional reviewing. The formal proceedings of the first instance of the summer school (2005) are published as volume 4143 in the Lecture Notes in Computer Science series of Springer-Verlag. SUMMER SCHOOL CHAIRS * Ralf Lämmel (Program Chair), Microsoft Corp., Redmond, USA. * João Saraiva (Organizing Chair), Universidade do Minho, Braga, Portugal. * Joost Visser (Program Chair), Universidade do Minho, Braga, Portugal. ADDITIONAL INFORMATION For additional information on the program, venue, and other details of the summer school, please consult the web page: http://www.di.uminho.pt/GTTSE2007 Note that registration for the summer school will open in January 2007. Before that time, those who wish to be notified personally when registration opens are welcome to send an expression of interest to gttse2007 at di.uminho.pt.

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ANN: Initial release of Quark Framework (tools and CAL language)
by Luke Evans 15 Oct '06

15 Oct '06

Further to the recent announcement here regarding the Business Objects Quark Framework for Java and its CAL language, I'm pleased to announce the availability of the first downloadable software, as well as some extra documents ("Effective CAL" and "Gem Cutter Manual"). This initial software release is designed primarily for those wishing to explore the CAL language, the Gem Cutter graphical language, and ICE (the interactive shell). In a short while (a week or two), we will update this release with the addition of an Eclipse plug-in (providing a CAL editor) and the full Java SDK for embedding functional logic into 'regular' Java applications, with dynamic control over the generation of new functions and their evaluation. There is a new home for downloading Quark Framework resources and getting the latest news: http://labs.businessobjects.com/cal A new discussion forum has also been set up to handle Q&A, feedback and the exchange of code samples. Details on the main Quark Framework page as above. Pending the release of the Eclipse editor, we have posted a CAL mode for the jEdit editor on the forum. Regards Luke

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Call for Contributions - HC&A Report (November 2006 edition)
by Andres Loeh 14 Oct '06

14 Oct '06

Dear Haskellers, it is nearly time for the eleventh edition of the ================================================================ Haskell Communities & Activities Report http://www.haskell.org/communities/ Submission deadline: 6 November 2006 (please send your contributions to hcar at haskell.org, in plain ASCII or LaTeX format) ================================================================ This is the short story: * If you are working on any project that is in some way related to Haskell, write a short entry and submit it to the me. * If you are interested any project related to Haskell that has not previously been mentioned in the HC&A Report, please tell me, so that I can contact the project leaders and ask them to submit an entry. * Feel free to pass on this call for contributions to others that might be interested. More detailed information: The Haskell Communities & Activities Report is a bi-annual overview of the state of Haskell as well as Haskell-related projects over the last, and possibly the upcoming 6 months. If you have only recently been exposed to Haskell, it might be a good idea to browse the June 2006 edition -- you will find interesting topics described as well as several starting points and links that may provide answers to many questions. Contributions will be collected until the beginning of November. They will be compiled into a coherent report which will appear sometime near the end of November. As always, this is a great opportunity to update your webpages, make new releases, announce of even start new projects, or to point at some developments you want every Haskeller to see! As the purpose of the report is to collect recent or current activities, I encourage you to update all existing summaries and reports. I will probably drop any topics that have not had any activity for the past year, i.e., since November 2005, but I would very much prefer you to present an updated description of the topic. Of course, new entries are more than welcome. Reports should generally be kept brief and informative, ranging from a few sentences to a few hundred words, to keep the whole report reasonably sized. Looking forward to your contributions, Andres (current editor) ----------------------------------- topics New suggestions for current hot topics, activities, projects, etc. are welcome - especially with names and addresses of potential contacts, but here is a non-exclusive list of likely topics (see also http://www.haskell.org/communities/topics.html ): General Haskell developments Haskell implementations Haskell extensions Standardization (Haskell', ...) Documentation Libraries Papers and Books Feedback Summaries of discussions in specialist mailing lists Conference reports Community activities Other Haskell information channels (TMR, Sequence, HWN, ...) Announcements Upcoming Haskell events Everything that's new or has had new releases Ongoing projects Reports on what's happening behind the scenes Confirmations that projects are still maintained Calls for contributions and contributors Tutorials Tools and Applications Released and unreleased Haskell applications Tools useful for Haskell programmers Experiences with using Haskell for a project Commercial uses of Haskell Even if your topic is not listed in this list, there's a good chance it has a place in the Report. Please get in touch with me. If you want to see an entry that hasn't been there in the past, but you are not the maintainer of the project, then please encourage the maintainers to write an entry/update, or ask permission to write the entry yourself. -------------------------- what should I write? That depends on your topic, but as a general rule, it shouldn't take you long. A simple sentence or two about your use of Haskell could go into the "Individual Haskellers" section. If you're a company, or if you're working on a project using Haskell as the implementation language, a paragraph on that could go into the "Applications" section. A typical summary report about a tool/library/project/application/... would be between 1 and 3 paragraphs of ASCII text (what's it about? major topics and results since the last report? current hot topics? major goals for the next six months?) plus pointers to material for further reading (typically to a home page, or to mailing list archives, specifications and drafts, implementations, meetings, minutes, ...). Browsing through previous editions should give you a good idea of the variety of possibilities, ranging from very brief to extensive. For those who prefer templates to fill in, the report is edited in LaTeX, and an entry template might look something like this: \begin{hcarentry}{(MYSTUFF)} \report{(MY NAME)} \status{(PROJECT STATUS IN ONE LINE)} \participants{(PARTICIPANTS OTHER THAN MYSELF)}% optional \makeheader Put the text here. What's following are suggestions for the content of an entry. (WHAT IS IT?) (WHAT IS ITS STATUS? / WHAT HAS HAPPENED SINCE LAST TIME?) (CAN OTHERS GET IT?) (WHAT ARE THE IMMEDIATE PLANS?) \FurtherReading \url{(PROJECT URL)} \end{hcarentry} This template and a style file to preview your document are available at http://haskell.org/communities/11-2006/template.tex http://haskell.org/communities/11-2006/hcar.sty

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APLAS'06: Early registration deadline: 20 October!!
by Manuel M T Chakravarty 13 Oct '06

13 Oct '06

*** Early Registration Deadline: 20 October *** Call for Participation 4th Asian Symposium on Programming Languages and Systems November 8-10, 2006 Sydney, Australia http://www.cse.unsw.edu.au/~aplas06/ http://www.kb.ecei.tohoku.ac.jp/aplas2006/ Scope of the Conference ----------------------- APLAS aims at stimulating programming language research by providing a forum for the presentation of recent results and the exchange of ideas and experience in topics concerned with programming languages and systems. APLAS is based in Asia, but is an international forum that serves the worldwide programming languages community. Conference Registration ----------------------- Registration information for APLAS 2006 is available at http://www.cse.unsw.edu.au/~aplas06/registration.html

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GADT: call for proper terminology
by oleg＠pobox.com 13 Oct '06

13 Oct '06

Niklas Broberg wrote: > Annotate the data type using a GADT: > data MyData a where > MyCon :: MyData a The range of the data constructor MyCon is the entire type MyData a -- so the above data type is the regular algebraic data type, and can be written just as data MyData a = MyCon which, some say, makes the fact 'a' is phantom, and the overall intent clearer. One may hear phrases how generally awesome and indispensable GADT are; it is distressing to realize then that sometimes (often?) one is talking about regular algebraic data types, only in the `where' syntax. It helps to reduce confusion about the merits of various features and additions to Haskell if we use the term GADT exclusively for truly _generalized_ algebraic data types.

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building shared objects
by Jeremy Wazny 13 Oct '06

13 Oct '06

Hi all, I'm wondering if anybody has had any success building shared objects from Haskell code on x86 Linux and/or Sparc Solaris. I have some Haskell source which I am trying to integrate into a C/C++ library which I am maintaining at the same time. The performance of the Haskell code is not an issue. The key limitation is that I need to be able to package the whole thing as a single .so object file. Put simply, I have a Haskell module which exports one of its functions via the FFI, using the ccall calling convention. I need to compile that module, and then link the resulting object, along with some other objects, into a single shared object. It seems there is no straightforward way to achieve this with any Haskell implementation on anything other than windows (by building a DLL.) A few possibilties have occurred to me, and I'd be interested to know if anybody has tried any of these with any success. 1. Use GHC with unregisterised libraries that have been compiled by gcc using -fPIC. I haven't been able to figure out how to actually build unregisterised libraries. I tried compiling the GHC 6.4.2 sources (using GHC 6.4.2) with `GhcUnregisterised = YES' in mk/build.mk, only to have the assembler fail. Has anyone else tried this recently? I sent a message to the GHC-users mailing list with more details, but haven't had a response yet. 2. Use nhc98 with libraries and run-time compiled with gcc and -fPIC. I have no idea whether this is feasible. 3. Link in a version of yhc's yhi interpreter, compiled with -fPIC. The shared object would have to produce some temporary files containing all of the pre-compiled byte code for the interpreter to read and execute. (We're already assuming that the platform the system runs on is completely trustworthy.) 4. Alternative 3 might also be possible using Hugs. I'm not sure that I can rely on any of these approaches - provided I can even get any of them working. Does anybody know of a good solution to this problem? The alternative is to admit defeat and rewrite all the Haskell code as C++, which is pretty depressing. Regards, Jeremy ____________________________________________________ Do you Yahoo!? Listen to your personal radio station on Yahoo!7 Music http://au.music.yahoo.com/launchcast/setup.asp

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Getting a function dependency graph from source
by Durward McDonell 13 Oct '06

13 Oct '06

Hello. This seems like a basic question, but I haven't been able to find an answer. I have a pile of Haskell code that is compiled into a library, and a Haskell program that uses this library. What I would like is something that will look at my program and follow the function calls until it gets to the Prelude. I want to know which functions in the library and in the Prelude actually get used (at least potentially). I believe Hat only looks at traces of an actual run of the program, and so doesn't quite give me what I want. I also think I could do this with the haskell-src library, but it looks like a lot of work to understand that and use it. Thanks. -- Durward McDonell durward.mcdonell(a)jhuapl.edu

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ICFP 2007 call for workshop proposals
by Graham Hutton 12 Oct '06

12 Oct '06

---------------------------------------------------------------------- CALL FOR WORKSHOP PROPOSALS ICFP 2007, the 12th ACM SIGPLAN International Conference on Functional Programming 1-3 October 2007, Freiburg, Germany The 12th ACM SIGPLAN International Conference on Functional Programming (ICFP 2007) will be held in Freiburg, Germany from 1st to 3rd October 2007. ICFP provides a forum for researchers and developers to hear about the latest work on the design, implementations, principles, and uses of functional programming. Proposals are invited for workshops to be affiliated with ICFP 2007 and sponsored by SIGPLAN. These workshops should be more informal and focused than ICFP itself, include sessions that enable interaction among the workshop attendees, and be fairly low cost. The preference is for one-day workshops, but other schedules can also be considered. The workshops themselves will be held on 30th September, 4th October, and 5th October 2007. SUBMISSION DETAILS Deadline for submission: 17th November 2006 Notification of acceptance: 15th December 2006 Prospective workshop organisers are invited to submit a completed workshop proposal form in plain text format to the ICFP 2007 workshop co-chairs (Graham Hutton and Matthias Blume), via email to icfp07-workshops at cs.nott.ac.uk by 17th November 2006. Please note that this is a firm deadline. Organisers will be notified if their proposal is accepted by 15th December 2006, and if successful are required to produce a final report after the workshop has taken place that is suitable for publication in SIGPLAN Notices. SELECTION COMMITTEE The workshop proposals will be evaluated by a committee comprising the following members of the ICFP 2007 organising committee, together with the members of the SIGPLAN executive committee. Graham Hutton University of Nottingham Workshops co-chair Matthias Blume TTI at Chicago Workshops co-chair Ralf Hinze Universitat Bonn General chair Norman Ramsey Harvard University Program chair FURTHER INFORMATION Any queries regarding ICFP 2007 workshop proposals should be addressed to the workshops co-chairs (Graham Hutton and Matthias Blume), via email to icfp07-workshops at cs.nott.ac.uk. USEFUL LINKS Call for workshop proposals http://www.cs.nott.ac.uk/~gmh/icfp07-workshops.html Workshop proposal form http://www.cs.nott.ac.uk/~gmh/icfp07-workshops-form.txt ICFP 2007 home page http://www.informatik.uni-bonn.de/~ralf/icfp07.html ---------------------------------------------------------------------- This message has been checked for viruses but the contents of an attachment may still contain software viruses, which could damage your computer system: you are advised to perform your own checks. Email communications with the University of Nottingham may be monitored as permitted by UK legislation.

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ANNOUNCE: Generic Haskell 1.60 (Diamond)
by Alexey Rodriguez Yakushev 11 Oct '06

11 Oct '06

Generic Haskell version 1.60 (Diamond) ==================================== We are happy to announce the fourth release of Generic Haskell, an extension of Haskell that facilitates generic programming. Generic Haskell includes the following features: * type-indexed values -- generic functions that can be instantiated on all Haskell data types. * type-indexed types -- types which are indexed over the type constructors underlying Haskell datatypes. The Generic Haskell compiler takes Generic Haskell source and produces Haskell code. Changes since 1.42 (Coral) -------------------------- * Generic Views as described in the Generic Views paper [1] are now sup- ported. * This release also corrects a few errors that occur with default cases, and some of the library functions have been improved. Download -------- The Generic Haskell compiler is available in source and binary distributions. Binaries for Linux and MacOSX are available. These are available from: http://www.generic-haskell.org/compiler.html The documentation is also available separately from that page. For more general information, point your browser to: http://www.generic-haskell.org Why Generic Haskell? -------------------- Software development often consists of designing datatypes, around which functionality is added. Some functionality is datatype specific, whereas other functionality is defined on almost all datatypes in such a way that it depends only on the structure of the datatype. A function that works on many datatypes in this way is called a generic function. Examples of generic functionality include editing, pretty-printing or storing a value in a database, and comparing two values for equality. Since datatypes often change and new datatypes are introduced, we have developed Generic Haskell, an extension of the functional programming language Haskell that supports generic definitions, to save the programmer from (re)writing instances of generic functions. The original design of Generic Haskell is based on work by Ralf Hinze. Pleasant programming, The Generic Haskell Team at Utrecht University info(a)generic-haskell.org [1] Stefan Holdermans, Johan Jeuring, Andres Löh, and Alexey Rodriguez. Generic views on data types. In Tarmo Uustalu, editor, Proceedings 8th International Conference on Mathematics of Program Construction, MPC 2006, LNCS 4014, pages 209 - 234, 2006, © Springer-Verlag.

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