May 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

2 1

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

8 13

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@)

1 2

ANNOUNCE: MonadCatchIO-foreign
by Antoine Latter 31 May '10

31 May '10

Hello Haskell, I'd like to announce a very small library in two flavors. The problem I'm trying to solve is that we have some capabilities for writing functions which are polymorphic over monad but still use IO capabilities - liftIO :: (IO a -> m a) from the packages transformers and mtl. The packages[1,2] MonadCatchIO offer similar polymorphism for the exception capabilities of the IO monad. The package MonadCatchIO-foreign offers similar polymorphism for the following functions: alloca, allocaBytes, allocaArray, allocaArray0 and withForeignPtr. It's a small thing, but I don't see why it should be written twice. Links on hackage: http://hackage.haskell.org/package/MonadCatchIO-mtl-foreign http://hackage.haskell.org/package/MonadCatchIO-transformers-foreign GitHub link: http://github.com/aslatter/MonadCatchIO-foreign Feedback, praise and adulation welcome. Antoine

2 1

Call for Papers: HLPP 2010 (DEADLINE EXTENSION)
by Frédéric Loulergue 31 May '10

31 May '10

We apologize if you receive this CfP multiple times. Please distribute ! ******************** DEADLINE EXTENSION ******************** ------------------------------------------------------------ Fourth International Workshop on High-level Parallel Programming and Applications (HLPP 2010) Baltimore, Maryland, September 25, 2010 Affiliated to ICFP 2010 ------------------------------------------------------------ AIMS AND SCOPE As processor and system manufacturers adjust their roadmaps towards increasing levels of both inter and intra-chip parallelism, so the urgency of reorienting the mainstream software industry towards these architectures grows. At present, popular parallel and distributed programming methodologies are dominated by low-level techniques such as send/receive message passing, or equivalently unstructured shared memory mechanisms. Higher-level, structured approaches offer many possible advantages and have a key role to play in the scalable exploitation of ubiquitous parallelism. This workshop provides a forum for discussion and research about such high-level approaches to parallel programming. Topics We welcome submission of original, unpublished papers in English on topics including (but not limited to) the following aspects of multi-core, parallel, distributed, grid and cloud computing: * High-level programming and performance models (BSP, CGM, LogP, MPM, etc.) and tools * Declarative parallel programming methodologies * Algorithmic skeletons and constructive methods * Declarative parallel programming languages and libraries: semantics and implementation * Verification of declarative parallel and distributed programs * Applications using high-level languages and tools * Teaching experience with high-level tools and methods PROGRAMME COMMITTEE * Anne Benoit (ENS Lyon, France) * Murray Cole (University of Edinburgh, UK) * Alexandros Gerbessiotis (New Jersey Institute of Technology, USA) * Christoph Kessler (Linköpings Universitet, Sweden) * Herbert Kuchen (University of Muenster, Germany) * Rita Loogen (University of Marburg, Germany) * Frédéric Loulergue (University of Orléans, France) * Kiminori Matsuzaki (Kochi University of Technology, Japan) * Samuel Midkiff (Purdue University, USA) * Susanna Pelagatti (University of Pisa, Italy) * Sukyoung Ryu (Korea Advanced Institute of Science and Technology, Korea) * Kazunori Ueda (Waseda University, Japan) IMPORTANT DATES * Submission (EXTENDED): 14 June 2010, 11:59 AM GMT * Notification: 12 July 210 * Final version: 28 July 2010 SUBMISSION Papers must be submitted online via EasyChair: https://www.easychair.org/account/signin.cgi?conf=hlpp2010 Submitted papers should be in portable document format (PDF), formatted using the ACM SIGPLAN style guidelines. The text should be in a 9pt font in two columns; the length is restricted to 10 pages. Papers must report previously unpublished work and not be submitted concurrently to another conference with refereed proceedings. Accepted papers must be presented at the workshop by one of the authors. Accepted papers will be published by the ACM and will appear in the ACM Digital Library. WEBSITE http://frederic.loulergue.eu/HLPP/hlpp2010/index.html

1 0

ANNOUNCE: Haskell Communities and Activities Report (18th ed., May 2010)
by Janis Voigtländer 28 May '10

28 May '10

On behalf of the many, many contributors, I am pleased to announce that the Haskell Communities and Activities Report (18th edition, May 2010) is now available in PDF and HTML formats: http://haskell.org/communities/05-2010/report.pdf http://haskell.org/communities/05-2010/html/report.html 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 I did. If you have not 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 sometimes 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 I 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 2010: target deadline for contributions to the November 2010 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 October (you could point me to them as well, and I 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! Janis Voigtlaender <hcar at haskell.org>

1 0

Gtk2Hs version 0.11.0 released
by Axel Simon 28 May '10

28 May '10

Dear all, the Gtk2Hs team is very happy to announce the release of version 0.11.0, the first release that comes in Cabal packages! Gtk2Hs is a collection of wrappers around the Gtk+ graphical user interface suite. However, it is more than just user interfaces! Using a subset of packages, you can also render high quality graphics and text to PDF, PS, PNG and SVG documents. Gtk2Hs consists of code that is partly generated but always adjusted by hand afterwards, especially the documentation. One of our aims it to make the Haskell interface self-contained and Haskell-lish. For example, memory management is fully automatic (of course!) and the store of widgets displaying tables or lists is a Haskell data structure. We have invested a great deal to make Gtk2Hs work in multi- threaded programs which was challenging given the concurrent garbage collector of GHC. Due to this effort, Gtk2Hs works from within GHCi and, of course, it works on Windows. This release has been tested on Linux, Mac OS X and Windows (XP/7). It can be built with GHC 6.10 and 6.12 and Cabal 1.6 and 1.8. However, since it's our first Cabal release, there might be rough edges, so any feedback is appreciated. The use of Cabal means that Gtk2Hs is now split into the following packages: • gtk2hs-buildtools: build tools, required to build from source • glib: object type system and data structures • gio: an OS-agnostic file access API • cairo: a 2D vector graphics library • pango: a Unicode-aware font rendering engine • gtk: the base GUI library • gconf: configuration database • glade: a library to build user interfaces from XML descriptions • gnomevfs: an OS-agnostic file access API (deprecated) • gstreamer: a multimedia streaming framework • gtkglext: an OpenGL widget • gtksourceview2: a source-code widget • soegtk: an API providing functions for Paul Hudak’s Haskell School of Expressions book • svgcairo: writing Cairo graphics to SVG files • vte: a terminal widget • webkit: a web-browser widget, based on Apple’s webkit library The aim is to concentrate future development on the core packages (i.e. the first six packages from the list above) and encourage external contributions to the remaining packages by putting them into their own repositories and granting write access to people. Through this process we hope to encourage external contributions and to accelerate the development of the core libraries. To install from sources, see: http://haskell.org/gtk2hs/download/ Documentation can be found here: http://haskell.org/gtk2hs/documentation/ Many thanks to all the external contributors that helped us prepare the release! Happy GUIing, Axel (on behalf of the Gtk2Hs team)

5 13

Sifflet visual programming language, release 0.1.6
by gdweber＠iue.edu 27 May '10

27 May '10

Sifflet 0.1.6 is now available on Hackage. New in this release: * Sifflet offers to save your work if you give the quit or open file command and have unsaved changes. * Sifflet now builds with Gtk2hs 0.11. * Some bug fixes and improved error checking. Sifflet is a visual, functional programming language. Sifflet programmers define functions by drawing diagrams. Sifflet shows how a function call is evaluated on the diagram. It is intended as an aid for learning about recursion. * A picture explains Sifflet better than words: please see the screenshot showing how to evaluate 3!: http://mypage.iu.edu/~gdweber/software/sifflet/home.html * Features: - Visual editor. - Visual tracer/debugger which shows how recursive and other function calls, expanding the computation when the student requests it, to support active learning. - A tutorial with 31 pictures and about as many pages. - Number, string, and list data types. - Palette with a small number of primitive functions. - Runnable examples of compound functions. * Download: http://hackage.haskell.org/package/sifflet * Home page: http://mypage.iu.edu/~gdweber/software/sifflet/home.html * Tutorial: http://mypage.iu.edu/~gdweber/software/sifflet/doc/tutorial.html -- ___ ___ __ _ / _ \ / _ \| | | | Gregory D. Weber, Associate Professor / /_\// / | | | /\ | | Indiana University East / /_\\/ /__| | |/ \| | http://mypage.iu.edu/~gdweber/ \____/\_____/\___/\__/ Tel. (765) 973-8420; FAX (765) 973-8550

1 0

PhD position available on `The Productive Use of Failure in Formal Methods'
by Gudmund Grov 27 May '10

27 May '10

--- apologies for multiple postings --- The mathematical reasoning research group in the School of Informatics at the University of Edinburgh is advertising for a PhD funded by the EPSRC project "AI4FM: Using AI to aid automation of proof search in Formal Methods". The proposed topic of the PhD is "The Productive Use of Failure in Formal Methods". ** DESCRIPTION The task allocated to this PhD will be to analyse ways in which proof attempts fail and are subsequently repaired. This analysis will be realised in a generic, strategy language for describing and classifying common forms of failure and repair. The strategy language will, in turn, be used, firstly, to describe how experts recover from failure and, secondly, to guide recovery during automated proof search of related proofs. Example failed proofs will be harvested from (a) the data from the toolset of Rodin formal methods system, (b) the manual, expert proof attempts on source theorems and (c) failed applications to target theorems of proof strategies abstracted from manual expert proofs of source theorems. Examples of repaired proof attempts will be harvested from the expert's work on failures of both types (b) and (c). This work will enhance the abilities of our prototype so it can benefit from initially failed proof attempts as well as successful ones. ** DEGREE OF DIFFICULTY A challenging project that requires mathematical sophistication, analytic skills and creativity in constructing the strategy language. ** BACKGROUND NEEDED A background in mathematics, logic or formal methods is required to provide the necessary mathematical maturity to undertake this project. ** CONTACT If you have any queries, please contact: - Gudmund Grov: ggrov(a)inf.ed.ac.uk , or - Alan Bundy: bundy(a)inf.ed.ac.uk. Please use our Schools PhD application page (see below) for applications. ** SOME LINKS - A description of the proposed PhD project: http://wcms.inf.ed.ac.uk/pgrguide/prospectus/projects-container/the-product… - The web page for the AI4FM project: http://www.ai4fm.org/ - Our School's PhD application page: http://www.inf.ed.ac.uk/postgraduate/phd.html ** IMPORTANT DATES There is no deadline for this application, but we do recommended candidates to apply as soon as possible since the position may be allocated without further notice. We are fairly flexible on the starting date, but would ideally like it to start between October 2010 and April 2011. ** ABOUT THE RESEARCH INSTITUTION AND RESEARCH GROUP The Edinburgh School of Informatics obtained the highest volume of 4* activity in its unit of assessment in RAE 2008. It contains world-class research groups in the areas of theoretical computer science, artificial intelligence and cognitive science. The Mathematical Reasoning Group in the School of Informatics has been engaged on the computational analysis, development and application of mathematical reasoning processes and their interactions since the mid 1970s (http://dream.inf.ed.ac.uk/) Its work is characterised by its unique blend of computational theory with artificial intelligence. It has pioneered work on proof planning, tactic learning, and ontology construction and evolution. -- The University of Edinburgh is a charitable body, registered in Scotland, with registration number SC005336.

1 0

New haskell-llvm mailing list.
by Erik de Castro Lopo 27 May '10

27 May '10

Hi all, I have set up a mailing list for discussion of haskell and LLVM related topics. All discussion on using Haskell with LLVM is relevant. That includes the haskell-llvm bindings on Hackage, custom LLVM bindings and directly generating LLVM IR code from haskell and passing that through the LLVM tools. In particular, this list is a place to share code, information, techniques and user experiences. The subscription page is here: http://projects.haskell.org/cgi-bin/mailman/listinfo/haskell-llvm Cheers, Erik -- ---------------------------------------------------------------------- Erik de Castro Lopo http://www.mega-nerd.com/

1 0