July 2010 - Haskell - Haskell.org

ANNOUNCE: ioctl 0.0.1
by Maciej Piechotka 13 Sep '15

13 Sep '15

A package for type-safe I/O control. Currently only ioctl is supported. Currently simply a extract from my tuntap fork TODO: - Return the integer as well as structure (will break the API) - Port for Windows Network.Socket.IOCtl (as soon as I manage to setup some sane environment on this platform) - Wrapping around DeviceIoControl Example (in hsc): data NotRead = NotRead instance NotRead Int where ioctlReq _ = #const FIONREAD notRead s = ioctlsocket' s NotRead Regards

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Announcing Djinn, version 2004-12-11, a coding wizard
by Lennart Augustsson 07 Apr '11

07 Apr '11

Howdy, y'all! I've written a small program that takes a (Haskell) type and gives you back a function of that type if one exists. It's kind of fun, so I thought I'd share it. It's probably best explained with a sample session. calvin% djinn Welcome to Djinn version 2005-12-11. Type :h to get help. # Djinn is interactive if not given any arguments. # Let's see if it can find the identity function. Djinn> f ? a->a f :: a -> a f x1 = x1 # Yes, that was easy. Let's try some tuple munging. Djinn> sel ? ((a,b),(c,d)) -> (b,c) sel :: ((a, b), (c, d)) -> (b, c) sel ((_, v5), (v6, _)) = (v5, v6) # We can ask for the impossible, but then we get what we # deserve. Djinn> cast ? a->b -- cast cannot be realized. # OK, let's be bold and try some functions that are tricky to write: # return, bind, and callCC in the continuation monad Djinn> type C a = (a -> r) -> r Djinn> returnC ? a -> C a returnC :: a -> C a returnC x1 x2 = x2 x1 Djinn> bindC ? C a -> (a -> C b) -> C b bindC :: C a -> (a -> C b) -> C b bindC x1 x2 x3 = x1 (\ c15 -> x2 c15 (\ c17 -> x3 c17)) Djinn> callCC ? ((a -> C b) -> C a) -> C a callCC :: ((a -> C b) -> C a) -> C a callCC x1 x2 = x1 (\ c15 _ -> x2 c15) (\ c11 -> x2 c11) # Well, poor Djinn has a sweaty brow after deducing the code # for callCC so we had better quit. Djinn> :q Bye. To play with Djinn do a darcs get http://darcs.augustsson.net/Darcs/Djinn or get http://darcs.augustsson.net/Darcs/Djinn/Djinn.tar.gz Then just type make. (You need a Haskell 98 implementation and some libraries.) And then start djinn. For the curious, Djinn uses a decision procedure for intuitionistic propositional calculus due to Roy Dyckhoff. It's a variation of Gentzen's LJ system. This means that (in theory) Djinn will always find a function if one exists, and if one doesn't exist Djinn will terminate telling you so. This is the very first version, so expect bugs. :) Share and enjoy. -- Lennart

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ANN: scan-0.1.0.3, a Haskell style scanner
by Christian Maeder 03 Aug '10

03 Aug '10

Dear Haskell friends, I like to announce a Haskell style scanner at http://hackage.haskell.org/package/scan documented under http://projects.haskell.org/style-scanner/ It's best used in conjunction with hlint http://community.haskell.org/~ndm/hlint/ and gives many suggestions regarding the file format. Feedback is welcome. Thanks Christian (Discussions should only be posted to either haskell-cafe@ or beginners@)

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ANN: syz-0.2.0.0
by Michael D. Adams 28 Jul '10

28 Jul '10

Hi all, This years Workshop on Generic Programming includes a generic zipper for Haskell that defines a Zipper type permitting zipper traversals over arbitrary instances of Data. A Haskell library based on those ideas is now available from Hackage at: http://hackage.haskell.org/package/syz Right now the documentation is very minimal so the best guide would be to have a look at the paper which includes a small tutorial. A pre-print is available at: http://www.cs.indiana.edu/~adamsmd/papers/scrap_your_zippers/ Bug reports as well as suggestions, feedback or contributions to the library or the documentation are most welcome and should be sent to me at adamsmd-AT-cs-DOT-indiana-DOT-edu. Michael D. Adams Ph.D. Student Indiana University http://www.cs.indiana.edu/~adamsmd/

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VSTTE 2010: Third Call for Participation -- Early Registration ends this week!
by Gudmund Grov 28 Jul '10

28 Jul '10

(Apologies if you receive multiple copies of this announcement) ***************************************************************** *** Second Call for Participation -- Early Registration ends this week! *** 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), and Matthew Parkinson (University of Cambridge); - Invited Tool Demo Presentations by Colin O’Halloran (ClawZ/Circus) , Bart Jacobs (VeriFast), Michael Jastram (ProB) and Joe Kinry (BONc/Beetlz); - A Verification Competition; - Industrial Tool Vendors; - Two workshops: Theory WS and Tools & Experiments WS; - A Summer School -- lectures given by Robert Atkey/Ewen Maclean, Alan Bundy/Lucas Dixon, Jane Hillston, Cliff Jones, Gerwin Klein, J Strother Moore, Natarajan Shankar and Graham Steel. 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 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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ANNOUNCE: jhc 0.7.4
by John Meacham 27 Jul '10

27 Jul '10

Announcing jhc 0.7.4! There have been a few major changes, the main one being that there is now support for a garbage collector. This drastically increases the number of programs which are feasable to compile with jhc. http://repetae.net/computer/jhc/ Any testing people can do with -fjgc would be greatly appreciated! My gameplan is to fix any issues that come up with the new gc and release a 0.7.5 that will have the GC enabled by default. This will probably be the first version of jhc I can recommend to non-developers with a good concience :). Once that is done I can implement a good strategy for library compatibility with other compilers and the standards. As it is, jhc has a mix of haskell 98 and haskell 2010 and the ghc base as its distributed libraries, basically whatever I found I needed in practice I added as I went along. This won't work in the long run. Major changes * a garbage colletor which can be enabled with '-fjgc' is available. after some more testing, I will make it the default in the 0.7.5 release. * A new memory allocator based on Jeff Bonwick's slab memory allocator for kernels. This means that in many cases, memory can be pulled off a slab and immediately used with no initialization, in addition, it allowed a rearrangement of the GC meta-data to optimizally use the cache. * packed representation of algebraic types, 'Maybe Foo' is actually represented in memory as a NULL pointer or just a 'Foo' with no tag bits. Combined with the slab allocator, this can double the number of some common values that can be put in a cache line. * some intense profiling of generated code and modification of the rts and code generator. Signifigant speed-ups in compiled programs are the result. Some other changes since 0.7.3 are * documentation updates, especially when it comes to the runtime. * ghc 6.12 support (it is in fact required now.) * no more monolithic 'Main'. the core pass moved to E.Main and the grin pass moved to Grin.Main. * generated C code is more compact and easier to debug. * more use of bytestring internally, improved performance * JHC_RTS_INCLUDE flag allows including the rts from an external file. useful for debugging/developing the RTS. * explicit register support in grin, for alternate back ends such as a NCG * Removed all compiler magic dealing with Eq,Bounded,Ord, and Bits. instances for these are specified in haskell code even for built in types now. * cleaned out some obsolete flags and options on command line. * updated applicative and support for newest version of 'containers' library. * bug updates * various bug fixes Below is the announcment for 0.7.3 in case you missed it. It's been a long time coming, but jhc-0.7.3 is here. If you have been following the darcs repository, there are not a whole lot of new changes, but there have been substantial fixes since 0.7.2. http://repetae.net/computer/jhc/ One of the most important ones is I have begun the process of standardizing on YAML for all external interfaces that may be useful to automation, this should make interfacing jhc with external tools written in any language much easier, and it will prevent me from spending time trying to invent proprietary formats every time I think of something new to spit out. right now it is used in 3 places: - dumping dependency info with --deps - library dumping with --list-libraries -v - annotating source code, for inputting to documentation generators via --annotate-source The main place it isn't used yet that I desire too is to replace the 'cabal' library description format with a true YAML file. jhc cabal files were never quite compatible with cabal ones anyway and naming them the same thing has been a source of connfusion. some of the other changes have been: features: - a lot more regression tests, many user submitted bugs are now regressions - support for using 'mock' to build rpms - System.Exit, System.Cmd added to base - better compatibility with ghc in some library functions - ui improvements in showing progress and errors - extended --list-libraries info - --deps dependency dumping - more francise compatible thanks to patches from droundy - more instances for bigger tuples added - uses editline if readline not available - select libraries by hash as well as version - add System.IO.Pipe - detect version of gcc needed for cross compiling to windows performance: - storage analysis - a very basic region inference enabled by default - deadcode analysis can see through partial applications now - profiled and sped up some library routines that were producing inellegant core. - figure out when top level grin functions call themselves recursively and turn them into explicit loops. bug fixes: - do expression in infix - fix strict newtype bug - U2U bug fixed - desugaring inside of list comprehensions fix - c generator doesn't mess up on unknown values - the compiler version is stored in the cache files, so multiple versions of jhc don't clobber each others cache entries - Ord instance for lists fixed - recursive type synonyms detected properly - make sure errno.h is included when errno is referenced - don't give a parse error when seeing ghc extensions to INLINE - qualified method names fix -- John Meacham - ⑆repetae.net⑆john⑈ - http://notanumber.net/

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"New FGL" naming survey
by Ivan Lazar Miljenovic 24 Jul '10

24 Jul '10

Whether or not the new FGL that Thomas Bereknyei and I are working on should keep the name was a semi-hot issue when we first mentioned the fact that we were working on a new version about a month ago. As such, I've created a survey here to try and find out what the Haskell community overall thinks we should call it: https://spreadsheets.google.com/viewform?formkey=dGpzMmFnUWY3Uktodk5wdHlLQk… More info can be found on the actual survey page. -- Ivan Lazar Miljenovic Ivan.Miljenovic(a)gmail.com IvanMiljenovic.wordpress.com

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ANNOUNCE: Haskell Platform 2010.2.0.0
by Don Stewart 23 Jul '10

23 Jul '10

We're pleased to announce the fifth release of the Haskell Platform: a single, standard Haskell distribution for everyone. Download the Haskell Platform 2010.2.0.0: http://hackage.haskell.org.nyud.net/platform/ (Caching server). The specification, along with installers (including Windows, Apple and Unix installers for a full Haskell environment) are available. The Haskell Platform is a single, standard Haskell distribution for every system, in the form of a blessed library and tool suite for Haskell distilled from the thousands of libraries on Hackage, along with installers for a wide variety of systems. It saves developers work picking and choosing the best Haskell libraries and tools to use for a task. When you install the Haskell Platform, you get the latest stable compiler, an expanded set of core libraries, additional development tools, and cabal-install – so you can download anything else you need from Hackage. What you get is specified here: http://hackage.haskell.org/platform/contents.html Thanks! -- The Platform Infrastructure Team

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ANNOUNCE: jhc 0.7.5
by John Meacham 22 Jul '10

22 Jul '10

Announcing jhc 0.7.5! This mainly fixes some bugs that came up in peoples testing of 0.7.4 and includes a lot more libraries in the standard install and better standards support. http://repetae.net/computer/jhc/ Any testing people can do with the new garbage collector -fjgc would be greatly appreciated! As far as I know, this release has no regressions when using the new GC, so it will be enabled by default if I get no reports of problems with this release. Major changes * The Garbage Collector now fully supports the Windows, OSX 10.5 (leapord), and OSX 10.6 (snow leapord) targets. * Lots of libraries, now that I have a somewhat general script to cut through the cabal the following are now included with the default install - haskell98 - flat-foreign (CForegin, etc..) - jhc - base (not the same as ghcs base, close enough for most tasks though) - applicative - containers - Diff - html - HUnit - pretty - safe - smallcheck - utility-ht - xhtml * updates to base libraries to bring them closer to haskell 2010 and ghc base. - updated Functor and Applicative - added Debug.Trace - added a few functions in h2010 not in h98 * support for adding valgrind annotations to generated source for debugging the RTS. * support for having the generated code annotate every heap location with useful profiling/debugging info. useful for debugging the RTS. * support for passing --win to the regression test driver to run all the tests cross-compiled for windows. * The Big HsName cleanup, finally got rid of old alegebraic HsName in favor of abstract Name and its faster operations, faster typechecking/frontend and code simplification opprotunities result. * improve the selftest. * bug fixes John -- John Meacham - ⑆repetae.net⑆john⑈ - http://notanumber.net/

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Call for Papers: TTSS'10 (4th International Workshop on Harnessing Theories for Tool Support in Software)
by Clemens Grelck 21 Jul '10

21 Jul '10

TTSS'10 — Call for Papers 4th International Workshop on Harnessing Theories for Tool Support in Software TTSS'10 15. November 2010 East China Normal University, Shanghai, China Satellite event of ICFEM 2010 http://www.iist.unu.edu/ttss10/ Conference Topics ******************* The aim of the workshop is to bring together practitioners and researchers from academia, industry and government to present and discuss ideas about: * How to deal with the complexity of software projects by multi-view modeling and separation of concerns about the design of functionality, interaction, concurrency, scheduling, and non-functional requirements * How to ensure correctness and dependability of software by integrating formal methods and tools for modeling, design, verification and validation into design and development processes and environments. Case studies and experience reports about harnessing static analysis tools such as model checking, theorem proving, testing, as well as runtime monitoring. The workshop will provide enough time for discussion on problems and research. Each presentation will be 25 minutes followed by 10 minutes discussion. Topics of interest include, but are not limited to, the following areas: * Models, calculi, and tool support for component-based and object-oriented software; * Mathematical frameworks, methods and tools for model-driven development; * Models, calculi, and tool support for integrating different scheduling, interaction and concurrency models in highly adaptable systems. Submission ************ TTSS invites authors to submit original and unpublished work. Submissions should include an abstract, key words, the e-mail address of the corresponding author, and must not exceed 15 pages using ENTCS style. Proceedings will be published as ENTCS. Further details are available from the workshop web-site http://www.iist.unu.edu/ttss10/. Selected papers of TTSS 2007-2010 will be invited to a special journal issue of Innovations in Systems and Software Engineering by Springer. Important Dates ***************** Submission deadline: 22. September 2010 (Wednesday, strict) Notification of acceptance: 1. October Workshop: 15. November 2010, ECNU, Shanghai, China Program Chairs **************** Min Zhang East China Normal University, China Volker Stolz University of Oslo, NO & UNU-IIST, Macau SAR, China Program Committee Members Luis Barbosa Universidade do Minho, Portugal Wei Dong National University of Defense Technology, China Clemens Grelck University of Amsterdam, NL Ralf Huuck NICTA, Australia Peter Gorm Larsen Engineering College of Aarhus, DK Einar B. Johnsen University of Oslo, Norway Carlo Montangero University of Pisa, Italy Thomas Noll RWTH Aachen University, Germany Jun Pang Univ. Luxembourg, Luxembourg Anders P. Ravn Aalborg University, Denmark Wuwei Shen Western Michigan University, US Axel Simon TU München, Germany R. Venkatesh TATA, India Michael Weber Univ. Twente, The Netherlands Naijun Zhan Institute of Software, CAS, China -- ---------------------------------------------------------------------- Dr Clemens Grelck Science Park 107 Universitair Docent 1098 XG Amsterdam Nederland Universiteit van Amsterdam Instituut voor Informatica T +31 (0) 20 525 7578 F +31 (0) 20 525 7419 Office F2.46 www.science.uva.nl/~grelck ----------------------------------------------------------------------

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