July 2010 - Haskell - Haskell.org

IFL 2010: 3rd CFP and 1st Call for Participation
by Don Stewart 14 Jul '10

14 Jul '10

3RD CALL FOR PAPERS and 1ST CALL FOR PARTICIPATION 22nd Symposium on Implementation and Application of Functional Languages (IFL 2010) September 1-3, 2010 Utrecht University Alphen aan den Rijn, The Netherlands http://www.cs.uu.nl/ifl2010 ******************************************************************************************* ** Submission and Registration are now both OPEN ** ** If you intend to participate in IFL 2010, help us by registering as soon as possible. ** ** ** ** Submission closes July 25, Registration closes August 1 ** ******************************************************************************************* After a first successful visit to the USA, the Symposium on Implementation and Application of Functional Languages returns to Europe for its 22nd edition. The hosting institution is Utrecht University in the Netherlands, although the conference itself will take place in the ornithological theme park Avifauna in Alphen aan den Rijn, situated conveniently close to Schiphol (Amsterdam Airport). The symposium dates are September 1-3, 2010. The goal of the IFL symposia is to bring together researchers actively engaged in the implementation and application of functional and function-based programming languages. IFL 2010 will be a venue for researchers to present and discuss new ideas and concepts, work in progress, and publication-ripe results related to the implementation and application of functional languages and function-based programming. Following the IFL tradition, IFL 2010 will use a post-symposium review process to produce formal proceedings which will be published by Springer Verlag in the Lecture Notes in Computer Science series. All participants in IFL 2010 are invited to submit either a draft paper or an extended abstract describing work to be presented at the symposium. At no time may work submitted to IFL be simultaneously submitted to other venues. Here we follow the ACM Sigplan republication policy as defined on http://www.sigplan.org/republicationpolicy.htm. The submissions will be screened by the program committee chair to make sure they are within the scope of IFL, and will appear in the draft proceedings distributed at the symposium. Submissions appearing in the draft proceedings are not peer-reviewed publications. After the symposium, authors will be given the opportunity to incorporate the feedback from discussions at the symposium and will be invited to submit a revised full article for the formal review process. These revised submissions will be reviewed by the program committee using prevailing academic standards to select the best articles, which will appear in the formal proceedings. INVITED SPEAKER Johan Nordlander of Lulea University, the designer and developer of the Timber language, is the invited speaker at IFL 2010. Timber is a functional programming language that draws some of its concepts from object-oriented programming, and has built-in facilities for concurrent execution. The language is specifically targeted at implementing real-time embedded systems. TOPICS IFL welcomes submissions describing practical and theoretical work as well as submissions describing applications and tools. If you are not sure that your work is appropriate for IFL 2010, please contact the PC chair at jur(a)cs.uu.nl. Topics of interest include, but are not limited to: language concepts type checking contracts compilation techniques staged compilation runtime function specialization runtime code generation partial evaluation (abstract) interpretation generic programming techniques automatic program generation array processing concurrent/parallel programming concurrent/parallel program execution functional programming and embedded systems functional programming and web applications functional programming and security novel memory management techniques runtime profiling and performance measurements debugging and tracing virtual/abstract machine architectures validation and verification of functional programs tools and programming techniques industrial applications of functional programming PAPER SUBMISSIONS Prospective authors are encouraged to submit papers or extended abstracts to be published in the draft proceedings and to present them at the symposium. All contributions must be written in English, conform to the Springer-Verlag LNCS series format and not exceed 16 pages. The draft proceedings will appear as a technical report of the Department of Computer Science of Utrecht University. SPONSORS IFL 2010 is sponsored by Microsoft Research. As a result we can offer decreased participation fees for Master students and PhD students who plan to attend or present at IFL 2010. PETER LANDIN PRIZE The Peter Landin Prize is awarded to the best paper presented at the symposium every year. The honored article is selected by the program committee based on the submissions received for the formal review process. The prize carries a cash award equivalent to 150 Euros. IMPORTANT DATES Draft proceedings submission deadline July 25, 2010 Registration deadline August 1, 2010 IFL 2010 Symposium September 1-3, 2010 Submission for review process deadline October 25, 2010 Notification Accept/Reject December 22, 2010 Camera ready version February 17, 2011 PROGRAM COMMITTEE Jost Berthold University of Copenhagen (DIKU), Denmark Olaf Chitil University of Kent, UK John Clements California Polytechnic State University, USA Matthew Fluet Rochester Institute of Technology, USA Andy Gill Kansas University, USA Jurriaan Hage (Chair) University of Utrecht, Netherlands Bastiaan Heeren Open University, Netherlands Ralf Hinze University of Oxford, UK John Hughes Chalmers University of Technology, Sweden Yukiyoshi Kameyama University of Tsukuba, Japan Gabriele Keller University of New South Wales, Australia Pieter Koopman Radboud University Nijmegen, Netherlands Luc Maranget INRIA, France Simon Marlow Microsoft Research, UK Marco T. Morazán Seton Hall University, USA Rex Page University of Oklahoma, USA Ricardo Peña Universidad Complutense de Madrid, Spain Sven-Bodo Scholz University of Hertfordshire, UK Tom Schrijvers Catholic University of Leuven, Belgium Don Stewart Galois, USA Wouter Swierstra Vector Fabrics, Netherlands Don Syme Microsoft, UK Peter Thiemann University of Freiburg, Germany Phil Trinder Heriott-Watt University, Scotland Janis Voigtländer University of Bonn, Germany Viktória Zsók Eötvös Loránd University, Hungary

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Call for Copy: Monad.Reader Issue 17
by Brent Yorgey 14 Jul '10

14 Jul '10

Whether you're an established academic or have only just started learning Haskell, if you have something to say, please consider writing an article for The Monad.Reader! The submission deadline for Issue 17 will be: **Friday, October 1, 2010** The Monad.Reader ~~~~~~~~~~~~~~~~ The Monad.Reader is a electronic magazine about all things Haskell. It is less formal than journal, but somehow more enduring than a wiki page. There have been a wide variety of articles: exciting code fragments, intriguing puzzles, book reviews, tutorials, and even half-baked research ideas. Submission Details ~~~~~~~~~~~~~~~~~~ Get in touch with me if you intend to submit something -- the sooner you let me know what you're up to, the better. Please submit articles for the next issue to me by e-mail (byorgey at cis.upenn.edu) Articles should be written according to the guidelines available from http://themonadreader.wordpress.com/contributing/ Please submit your article in PDF, together with any source files you used. The sources will be released together with the magazine under a BSD license. If you would like to submit an article, but have trouble with LaTeX please let me know and we'll work something out.

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ANNOUNCE: Haskell 2010 Report (final)
by Simon Marlow 14 Jul '10

14 Jul '10

The Haskell 2010 report is done! I've uploaded it to www.haskell.org, and linked it from the main Haskell wiki: http://www.haskell.org/haskellwiki/Language_and_library_specification online HTML version: http://www.haskell.org/onlinereport/haskell2010 PDF: http://www.haskell.org/definition/haskell2010.pdf Thanks to everyone who commented on earlier drafts, many bugs were fixed as a result. Changes relative to the 2nd draft: - added Numeric (somehow forgotten before) - added System.IO.Error.{catch,try,ioError} - lots of rendering and typesetting bugs fixed I now formally relinquish the Haskell report editor's hat, and hand it over to the chair of the Haskell 2011 committee, Malcolm Wallace. Cheers, Simon PS. don't forget there will be a new revision of Haskell this year, and time is getting short to submit proposals. For instructions on getting involved, see http://hackage.haskell.org/trac/haskell-prime

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Re: [Haskell-cafe] Re: [Haskell] ANNOUNCE: Haskell 2010 Report (final)
by John Meacham 12 Jul '10

12 Jul '10

On Tue, Jul 06, 2010 at 09:48:20PM +0300, Roman Cheplyaka wrote: > Greetings! Now, can different compiler/interpreter authors make > statements about support of this standard in their compilers please? Jhc supports all the language features of haskell 2010 except pattern guards. (ironic as I am a huge fan of said feature.) The library situation is more complicated, there is tension between haskell 98, haskell 2010, and supporting code in the wild, which often assumes some specific version of ghc's base, which doesn't quite conform to either. My current thinking is to give up supporting base directly as a clone of ghc's and rather support just haskell 98 and haskell 2010 modes "natively", then compatability libraries (called things like ghc-base-4 and ghc-base-3 perhaps) would be independent projects and not tied to jhc releases. jhc 0.7.4 which supports garbage collection and a speedier runtime and better support for external build systems will be out soon. My goal is one more point release before 0.8.0 which will have full haskell 2010 and 98 support. John -- John Meacham - ⑆repetae.net⑆john⑈ - http://notanumber.net/

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ANNOUCE: graphviz-2999.10.0.0
by Ivan Lazar Miljenovic 12 Jul '10

12 Jul '10

I'm pleased to announce a new version of my graphviz [1] library that provides bindings to the Graphviz [2] suite of tools for visualising graphs. [1]: http://hackage.haskell.org/package/graphviz [2]: http://graphviz.org/ Changes in this release: * I followed my own advice and put in bounds on the version of FGL it used... * Conversion of FGL-style graphs to `DotRepr` values is now achieved using the new `GraphvizParams` configuration type. This allows us to define a single parameter that stores all the conversion functions to pass around rather than having to pass around several functions. This also allows all the non-clustered and clustered functions to be collapsed together, whereas what used to be handled by the primed functions is now achieved by using the `setDirectedness` function. There are three default `GraphvizParams` available: - `defaultParams` provides some sensible defaults (no attributes or clustering). - `nonClusteredParams` is an alias of `defaultParams` where the clustering type is explicitly set to be `()` for cases where you don't want any clustering at all (whereas `defaultParams` allows you to set your own clustering functions). - `blankParams` sets all fields to be `undefined`; this is useful for situations where you have functions that will set some values for you and there is no sensible default you can use (mainly for the clustering function). * Expansion of the `DotRepr` class: - More common functions are now defined as methods (`getID`, etc.). - The ability to get more information about the structure of the `DotRepr` graph, as well as where all the `DotNode`s are, etc. - `graphNodes` now returns `DotNode`s defined only as part of `DotEdge`s, and will also merge duplicate `DotNode`s together. - `graphNodes` and `graphEdges` also return `GlobalAttributes` that apply to them. * The `Point` type now only has one constructor: `Point Double Double`. The `Int`-only constructor was present due to historical purposes and I thought that the `Pos` value for a `DotNode` would always be a pair of `Int`s; this turns out not to be the case (and accounted for some bugs in older versions of my SourceGraph tool; it's taken me this long to remember to fix this...). * `SortV` and `PrismOverlap` now only take `Word16` values rather than `Int`s, as they're not meant to allow negative values (the choice of using `Word16` rather than `Word` was arbitrary, and because it's unlikely those values will be large enough to require the larger values available in `Word`). * `NodeCluster` has been generalised to not have to take an `LNode` for the node type; the type alias `LNodeCluster` is available if you still want this. * Several documentation typos fixed, including one spotted by Kevin Quick. * The test-suite now allows running individual tests. -- Ivan Lazar Miljenovic Ivan.Miljenovic(a)gmail.com IvanMiljenovic.wordpress.com

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ANNOUNCE: fgl-5.4.2.3
by Ivan Lazar Miljenovic 12 Jul '10

12 Jul '10

I'm pleased to present the first new release of fgl [1] since Thomas Bereknyei took over maintaining it from Martin Erwig. [1] http://hackage.haskell.org/package/fgl Before people start panicking, rioting, etc., please check the version number: this is just a bug-fix release, and not the complete re-write version which we've been talking about (since we got a little sidetracked, etc.). As such, the API hasn't changed, and this should fit right in to packages already using fgl (sorry to all those people who followed my advice and put "fgl == 5.4.2.2" in the build-depends fields of their packages' .cabal files, but I didn't expect to make another 5.4.y release). The exact change that has been made is to fix a bug pointed out to me by Tristan Allwood, in that Data.Graph.Inductive.PatriciaTree didn't support multiple edges (and furthermore this wasn't specified in the documentation). This has now been rectified. As an indication of what these changes mean, see this sample call graph produced by my SourceGraph program; when using PatriciaTree from fgl-5.4.2.2 the lines were all the same thickness; now there is among other things a loop of width 32 on getExp and a line of width 7 from getExp to maybeEnt. -- Ivan Lazar Miljenovic Ivan.Miljenovic(a)gmail.com IvanMiljenovic.wordpress.com

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ANNOUNCE: SourceGraph-0.6.1.1 and Graphalyze-0.10.0.0
by Ivan Lazar Miljenovic 12 Jul '10

12 Jul '10

I'm pleased to announce updated versions of SourceGraph [1] (my graph-theoretic static analysis tool for Haskell) and Graphalyze [2] (a library for graph-theoretic analysis of relationships in discrete data). [1]: http://hackage.haskell.org/package/SourceGraph [2]: http://hackage.haskell.org/package/Graphalyze This version of SourceGraph now (should) only consider executables listed in .cabal files as being buildable, and both packages have been updated to use the latest versions of fgl (as well as following my own advice in putting an upper bound on the version of fgl being used...), graphviz and haskell-src-exts (SourceGraph only). Please note that SourceGraph-0.6.1.0 was a version I forgot to upload (and just realised this when I wondered why it wasn't appearing on Hackage...). The big change that should be apparent with this version of SourceGraph is that thanks to the changes I just made to the newly-uploaded fgl-5.4.2.3, multiple edges are finally being handled/visualised properly; for example see the nice thick lines in http://code.haskell.org/~ivanm/Sample_SourceGraph/SourceGraph/graphs/codeCo… (which represents among other things 32 recursive calls within getExp and 7 calls from getExp to maybeEnt). I forgot to put this in the TODOs, but here are my future plans for these packages. They're rather ambitious and I have no idea when I'll get around to them, but for all intents the only work I'm going to do on them until I do these splitting up goals is bug-fixes, etc. Graphalyze ---------- Graphalyze is going to fade away: I'm going to integrate its data -> graph conversion utilities into either my new graph library I'm going to work on during AusHack or into the successor for fgl Thomas Bereknyei and are working on (whatever we'll end up calling it), the Data.Graph.Analysis.Algorithms modules into graph-algorithms and fgl-algorithms packages and the reporting stuff into its own reporting library with different backends (pandoc, blaze, etc.). SourceGraph ----------- I want to split out and formalise the whole call-graph definitions and concepts into its own library and have sub-libraries for different languages to be able to have their own code -> call-graph conversions (so it can also be used for language-c, language-python, etc.). SourceGraph itself would then be more flexible in terms of what languages it can deal with (so it might even be possible to integrate C source files in a Haskell package into the call graph!). -- Ivan Lazar Miljenovic Ivan.Miljenovic(a)gmail.com IvanMiljenovic.wordpress.com

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ANN: HaRe-0.6, now on Hackage
by Chris BROWN 07 Jul '10

07 Jul '10

Dear Haskellers, As part of our project on Refactoring Functional Programs http://www.cs.kent.ac.uk/projects/refactor-fp/ we are pleased to announce the availability of HaRe 0.6 on Hackage. http://hackage.haskell.org/package/HaRe-0.6 Please see the README.txt for build/use instructions and known issues, and let us know about any problems, bugs, suggestions or additional platforms you can confirm as working. Happy Refactoring! The HaRe Team (Chris Brown, Huiqing Li, Simon Thompson) Background: Refactoring is the process of changing the structure of programs without changing their functionality, i.e., refactorings are meaning-preserving program transformations that implement design changes. For more details about refactoring, about our project and for background on HaRe, see our project pages. HaRe - the Haskell Refactorer: HaRe is our prototype tool supporting a collection of refactorings for Haskell 98 (see README.txt for known issues and limitations). It is implemented as a separate refactoring engine (on top of Programatica's Haskell frontend and Strafunski's generic traversal strategy library), with small scripting frontends that call this engine from either Vim or Emacs.

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analogous functions in Sound.File.Sndfile
by Maria Gabriela Valdes 07 Jul '10

07 Jul '10

Does anybody know what are the analogous functions and data types in the haskell library "Sound.File.Sndfile" of the libsndfile library in C ? data type : SNDFILE function: sf_open function : sf_read_short Thanks in advance, -- Maria Gabriela Valdes G. Linux Registered User #485743

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Second draft of the Haskell 2010 report available
by Simon Marlow 06 Jul '10

06 Jul '10

The second draft of the Haskell 2010 report is now available in PDF and HTML formats (the PDF looks a lot nicer): http://www.haskell.org/~simonmar/haskell-2010-draft-report-2.pdf http://www.haskell.org/~simonmar/haskell-2010-draft-report-2/haskell.html relative to the first draft, which was only publicised on the haskell-prime mailing list, I have now updated the libraries too. Rather than update all the library documentation manually, I (perhaps rashly) decided to make a LaTeX backend for Haddock instead, and generate the report automatically from the library source code. Getting this to work turned out to be a lot more effort than I anticipated, but I think the results are quite attractive. Once the new Haddock backend is incorporated upstream, we'll finally have the ability to generate decent typeset API documentation. Furthermore, this should make it much easier to incorporate more libraries in future versions of the Haskell standard, should we decide to do so. Right now, the HTML version of the report is generated from the LaTeX sources, including the libraries. We could use the Haddock HTML output instead, but that would entail some difficulties with cross-references from the language part of the report to the libraries, which is why I've left it this way for now. This is why the libraries part of the report is bereft of hyperlinks in HTML; but at least it is well indexed in the PDF version. Summary of the library changes in Haskell 2010 relative to Haskell 98 and the FFI specification: * All libraries have been updated to their hierarchical names * The following library modules were dropped from the standard, due to being obsolete or superseded. Replacements are not part of the standard yet, but it is expected that they will be replaced in the future: Directory, System, Time, Locale, CPUTime, Random In the case of System, some functions have moved to the new modules System.Environment and System.Exit. * Foreign.Marshal.Error: functions on IOError moved to System.Error (this is where they've been in base for ever). * Data.List: added intercalate, subsequences, permutations, foldl', foldl1', stripPrefix (H2010 Data.List matches the current base version). * Data.Char: various additions of Unicode predicates (e.g. isLetter, isMark, isNumber), the GeneralCategory type and generalCategory. (matches the base version) * Control.Monad: added forM, forM_, (>=>), (<=<), forever, foldM_, replicateM, replicateM_ (matches the base version). * System.IO: added fixIO, hSetFileSize, hTell, hIsTerminalDevice, hSetEcho, hGetEcho, hShow. The base version has various additions: hGetBuf/hPutBuf, binary Handles, encodings, and newline support, but I erred on the side of being conservative here: these APIs need discussion, and in some cases are probably not suitable for the standard in their current state at all. * System.IO.Error: new module, providing functionality that was in Foreign.Marshal.Error in the FFI spec. * System.IO.Exit: new module, functionality moved from H98 System * System.Environment: new module, functionality moved from H98 System We expect to provide exactly these libraries in GHC 6.14, although the exact mechanism has yet to be decided; for discussion see http://www.haskell.org/pipermail/haskell-prime/2010-April/003158.html Comments on the draft report are welcome, before I finalise this and sign off on Haskell 2010. Cheers, Simon

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