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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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VSTTE 2010: First Call for Participation
by Gudmund Grov 06 Jul '10

06 Jul '10

(Apologies if you receive multiple copies of this announcement) ***************************************************************** *** First Call for Participation *** Third International Conference on Verified Software: Theories, Tools, and Experiments Edinburgh, Scotland August 16th-19th, 2010 http://www.macs.hw.ac.uk/vstte10 SPONSORS: NSF, EPSRC, Microsoft Research, SICSA, Altran Praxis, SSEI, FME, Contemplate, Heriot-Watt University ****************************************************************** The Third International Conference on Verified Software: Theories, Tools, and Experiments follows a successful inaugural working conference at Zurich (2005) and a successful conference in Toronto (2008). This conference is part of the Verified Software Initiative (VSI), a fifteen-year, cooperative, international project directed at the scientific challenges of large-scale software verification. VSI also includes UKCRC's Grand Challenge 6, i.e. Dependable Systems Evolution. PROGRAMME The programme includes keynote presentations by Tom Ball (Microsoft), Gerwin Klein (National ICT Australia), Matthew Parkinson (University of Cambridge). There will also be a Summer School, Invited Tool Demo Presentations, a Verification Competition, Industrial Tool Vendors as wells as two workshops: Theory WS and Tools & Experiments WS. A provisional programme is available at http://www.macs.hw.ac.uk/vstte10/Programme.html VENUE VSTTE 2010 is being hosted by Heriot-Watt University in Edinburgh. The conference dates coincide with the 2010 Edinburgh International Festival and the Edinburgh Festival Fringe -- collectively the largest annual arts festival on the planet! The technical programme will take place in the Edinburgh Conference Centre (Heriot-Watt University campus), where accommodation will be available at very competitive rates for festival time. Social events will be arranged within the city centre, making VSTTE an unique cultural and scholarly event for 2010! SOCIAL EVENTS As well as a welcome reception and conference banquet, SICSA are sponsoring a special drinks reception in the Informatics Forum at the heart of the Festival on August 17th. STUDENT SUPPORT Limited support for students wishing to attend VSTTE 2010 is available. Please contact vstte10(a)macs.hw.ac.uk for more details. REGISTRATION Online registration is available from http://www.macs.hw.ac.uk/vstte10_reg/Registration.php Early registration ends on July 31st. -- The University of Edinburgh is a charitable body, registered in Scotland, with registration number SC005336.

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