- Haskell - Haskell.org

Re: [Haskell-cafe] ANN: The Monad.Reader Issue 9: SoC special
by Yitzchak Gale 19 Nov '07

19 Nov '07

Wouter Swierstra wrote: >> I am pleased to announce that a new issue of The Monad.Reader is now >> available: >> http://www.haskell.org/haskellwiki/The_Monad.Reader Dougal Stanton wrote: > Thanks Wouter, the haiku look great! ;-) I agree, they are fantastic! (And they are not "short".) Perhaps you were inspired by the classic 1998 Salon haiku challenge. In any case, I think a reference is appropriate: http://archive.salon.com/21st/chal/1998/01/26chal.html http://archive.salon.com/21st/chal/1998/02/10chal2.html Regards, Yitz

1 0

ANN: The Monad.Reader Issue 9: SoC special
by Wouter Swierstra 19 Nov '07

19 Nov '07

I am pleased to announce that a new issue of The Monad.Reader is now available: http://www.haskell.org/haskellwiki/The_Monad.Reader Issue 9 is a "Summer of Code Special" - it consists of three articles from student participants of Google's Summer of Code, describing the projects they worked on: * Thomas Schilling Cabal Configurations * Jason Dagit Darcs Patch Theory * Mathieu Boespflug TaiChi: how to check your types with serenity The Monad.Reader is a quarterly magazine about functional programming. It is less formal than a journal, but somehow more enduring than a wiki page or blog post. If you'd like to write something for the next issue of The Monad.Reader, please get in touch. I haven't fixed the deadline for the next issue just yet. I hope to send out an official call for copy fairly soon. Enjoy! Wouter 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.

1 0

Bang patterns and declaration order
by Iavor Diatchki 19 Nov '07

19 Nov '07

Hello, I was playing around with "bang patterns" and I noticed that when combined with asynchronous exceptions they can lead to programs where the order of the declarations in a binding group is important! Here is an example: > import Control.Exception > import Prelude hiding (catch) > > main = putStrLn =<< eval_order > > test = "no exception" > where !_ = error "top down" > !_ = error "bottom up" > > eval_order = evaluate test `catch` \e -> > case e of > ErrorCall txt -> return txt > _ -> throw e Of course, this is a contrived exampled but, as far as I know, this was not possible in Haskell before (if anyone has an example to the contrary please send it to the list). By the way, with GHC 6.8.1 the above program prints "bottom up". This means that when there are multiple "banged" bindings they are evaluated starting with the last one in the text. I imagine than in most programs this is not particularly important, but it seems to me that it would be a bit nicer if we were to adjust the translation so that bindings were evaluated top to bottom (e.g., like in ML). Finally, the above program is accepted by GHC 6.8.1 without any special flags (e.g., no need for -XBangPatterns). Is this intentional? -- Iavor

5 4

Re: AmeroHaskell
by John Peterson 18 Nov '07

18 Nov '07

It would be great if someone put a meeting together during SIGCSE - that's in Portland March 12-15, 2008. That's about the only time I get to crawl out from under my classes and interact with the outside world. We could announce something on the SIGCSE mailing list and maybe pull in some interesting outsiders. John jpeterson(a)western.edu

1 0

AmeroHaskell
by Derek Elkins 18 Nov '07

18 Nov '07

[Reply-To set to Haskell-Cafe] At http://www.haskell.org/haskellwiki/AmeroHaskell is a page for a proposed Haskell meeting originally aimed for the south eastern United States. Quite a few people registered interest, but few of them were in the SE. This email is to prompt any more interest in such a meeting without any fixed geographical locale. To get an idea of what it would be like, it would be something along the lines of http://www.haskell.org/haskellwiki/AngloHaskell Anyone interested in an Haskell meeting anywhere in America mark your interest and what region would be good for you. Anyone who could provide a venue would also be highly appreciated. It may well end up being AmeroHaskells with several meetings in different regions. However, to put things in motion for something concrete at all, we're hoping to put together a meeting taking place in the Portland area as that seems most convenient to the most people who had registered interest in AmeroHaskell and an easy place to find a venue. In that vein, while no plans have been made, something aimed for the January/February time-frame and probably hosted by Galois, if they are willing, has been discussed. The event would probably be a few days long and would involve some informal (and perhaps impromptu) talks and hanging out, getting to know each other as more than an IRC handle, and some cooperative hacking. Again, see the AngloHaskell page for an idea. Anyone who is interested in presenting a talk about anything they are doing or are interested in in Haskell or Haskell-related topics please suggest that on the wiki page or reply here! Admittedly a January/February time-frame does not provide a lot of head time, but the talks are aimed at a friendly chat tone rather than a formal presentation. Feel free to bring your half-baked ideas.

1 0

Haskell binding to the LibTomCrypt library
by Bulat Ziganshin 17 Nov '07

17 Nov '07

Hello haskell, as part of my archiver [1], i've made some FFI bindings to the open-source, public license cryptographic library LibTomCrypt [2] this currently includes * AES, Blowfish, Twofish and Serpent encryption algorithms * CTR and CFB streaming modes * SHA-512 hash * FORTUNE cryptographic random numbers generator * PKCS5#2 password-based key derivation algorithm but may easily be extended to everything else included in the LibTomCrypt library you may just download my sources and use it as is, but it will be a real pain. Don Stewart suggested to cabalize the binding and upload it to hackage as separate lib. i may do it if there are real users for such package. for the supposed API look at [3], encryption API will be essentially the same - using callbacks to read/write data. because my program targeted to the same niche as winzip, the binding provides almost the same service - i.e. ability to encrypt/decrypt stream of data with password using cryptographically sound algorithms. you will be able to use it like this: encrypt "aes" password (hGetBuf infile) (hPutBuf outfile) decrypt password (hGetBuf infile) (hPutBuf outfile) if you need such library - please yell me. i will work on it only if there will be enough real users [1] http://sourceforge.net/project/showfiles.php?group_id=207033 [2] http://libtom.org [3] http://www.haskell.org/bz/CompressionLibrary.htm -- Best regards, Bulat mailto:Bulat.Ziganshin@gmail.com

2 1

need some help with type inference
by Hal Daume III 16 Nov '07

16 Nov '07

Hi Haskellers -- It's been a while since I've frequented this list, but I'm hoping I can stir up some help. My problem isn't Haskell-specific (so please forgive the blanket email), but it *is* related to something written in Haskell, so hopefully that's sufficient :). Basically, the deal is that I have a language for which I need type inference. I currently have something hacked together which works "most of the time", but I'd really like to do it right. The problem is that the type system is unlike anything I've encountered before. There are two "base" types, Real and Integer (which I'll call R and I, respectively). In pseudo-Haskell: > data Base = R Double | I Integer Then, a Type is either a Base type or it's an array with *known* bounds of Types. We can thus get matrices by having arrays of arrays. For instance: > type Bound = ... > data Type = Base Base | Array Bound Type This would all be well and good. The complication is that Bounds can either be given by integer bounds (eg., "10") or by variables (eg., "N"). So, we might write the type of an array of 10 integers as "I[10]" or an array of N reals as "R[N]". Okay, so that's not so bad yet. The complication is that the Kth bound can refer to any of the previous K-1 bounds. For instance, the type "R[N][D[#1]]" means an array of dimension N, each of whose elements is a real array of dimension D[n], where n is the first index. That is, R[5] is an array of length D[5]. Necessarily, D is of type I[N]. And now I need to do type inference/type checking in this system. I have a strong feeling it's undecidable, but I'm fine with that. I don't have a problem require type annotations and, at least for the example programs I have written in this language, I've only once ever been required to write a type annotation even with my very conservative hacky type inference. So the question is: has anyone encountered a type system like this before? Anyone want to offer suggestions? I think probably it's most appropriate to reply off-list, since I don't want to bog the list down. Best, - Hal p.s., the language is here: http://www.cs.utah.edu/~hal/HBC -- Hal Daume III --- me AT hal3 DOT name | http://hal3.name "Arrest this man, he talks in maths." | http://nlpers.blogspot.com

1 0

CFP FICS 2008
by Huibiao Zhu 14 Nov '07

14 Nov '07

(We apologize for multiple copies of this Call.) ============================================================== FICS 2008 The First International Conference on Foundations of Informatics, Computing, and Software (http://www.sei.ecnu.edu.cn/~fics08/) June 3-6, 2008, Shanghai, China For more information e-mail: fics08(a)sei.ecnu.edu.cn ============================================================= Foundations of Informatics, Computing and Software (FICS) is a new conference aimed at being one of the leading conferences in theory, methodologies and systems spanning several emerging areas of computer science, such as programming languages, software engineering, verification and informatics (bio, medical). The 1th International Conference FICS will take place on the campus of East China Normal University (ECNU), Shanghai, China, from June 3 to June 6, 2008. This Conference is intended to be a forum for researchers in several areas with topics including but not limited to: *Algorithm and Computability *Bioinformatics and Systems Biology *Computational Complexity *Concurrent and Parallel Computing *Domain Theory and Semantics Structures *Formal Methods and Software *Formalization Methods and Theory * Theory ? Logic and Formal Verification *Probabilistic Systems *Process Algebra *Quantum Computing *Semantic Web and Ontology *Term Rewriting SUBMISSIONS Guidelines: Authors are invited to submit papers presenting original and unpublished research not concurrently considered for publication elsewhere. Papers should not exceed 14pages and should be formatted according to the ENTCS article style. Submissions must be made through Easychair at: http://www.easychair.org/FICS2008/ before the submission deadlines for abstract and full paper respectively. All submissions will be reviewed by at least three members of the program committee. They will be judged on the basis of originality, contribution to the field, technical and presentation quality, and relevance to the conference. The proceedings of the conference will appear as a volume in ENTCS. Pre-proceedings will be distributed at the conference. IMPORTANT DATES ----------------- Abstract Submissions: Friday, 28 Dec. 2007 Paper Submissions: Friday, 11th Jan. 2008 Notification of acceptance: Friday, 22th Feb. 2008 Camera ready deadline: Friday, 7th Mar. 2008 Conference: Monday, 3rd Jun. 2008 ORGANIZATION ----------------- Conference Chair: Jifeng He, (ECNU, China) Steering Committee: Frahad Arbab (CWI, The Netherland) Manfred Broy ( TU Munchen, Germany) Yixiang Chen (ECNU, China) Pierre-Louis Curien (PPS, France) Jifeng He(Chair)(ECNU, China) Tony Hoare(Oxford Uni., UK) Huimin Lin (SI, China) Prakash Panangaden (McGill Uni., Canada) Guo-qiang Zhang(Chair) (CWRU, US) Program Committee: Li Chen (UDC, US) Yixiang Chen (ECNU, China) Manfred Droste (Uni-Leipzig, Germany) Yuxi Fu (Shanghai Jiaotong Uni., China) Masahito Hasegawa (Kyoto Uni., Japan) Pascal Hitzle (Uni-Karlsruhe, Germany) Ying Jiang (SI, Academy of Science, China) Zhi Jin (MASS, Academy of Science, China) Achim Jung (Birmingham Uni. UK) Klaus Keimel (DTU, Germany) Hong Mei (Beijing Uni., China) Madhavan Mukund (Chennai Mathematical Institute, India) Dag Normann (Oslo Uni. Norway) Catuscia Palamidessi (INRIA FUTUR, Paris) Prakash Panangaden (McGill Uni., Canada) Michel Schellekens (National University of Ireland, Ireland) Dieter Spreen (University of Siegen, Germany) Shanghua Teng (Boston Uni., US) James Worrell (Oxford Uni.,UK) Kwangkeun Yi (Seoul National Uni., Korea) Guo-qiang Zhang (CWRU, US) Hong Zhu (ECNU, China) Publicity Chair： Huibiao Zhu (ECNU, China) Local Organization Committee: Lu Han (ECNU, China) Yuanyuan He (ECNU, China) Yanfang Ma (ECNU, China) Jie Yang (ECNU, China) Min Zhang (Chair) (ECNU, China) Jie Zhou (ECNU, China) Keynote Speakers: Patrick Cousot (ENS, France, http://www.di.ens.fr/~cousot) Vincent Danos (PPS, France, http://www.pps.jussieu.fr/~danos/) Peter O’Hearn (QMW, UK, http://www.dcs.qmul.ac.uk/~ohearn/) Glynn Winskel (Cambridge Uni., UK, http://www.cl.cam.ac.uk/~gw104/) Ming-Sheng Ying (Tsinghua Uni., China)

1 0

fun at York (reminder)
by Colin Runciman 13 Nov '07

13 Nov '07

Fun people, There will be Fun in the Afternoon at York on Thursday 22 November. See http://sneezy.cs.nott.ac.uk/fun/ for details. If you plan to come, and have not already mailed to say so, please send me a non-empty message with EITHER "curried fun" OR "uncurried fun" as the subject line -- participants opting for curried fun will convene at a nearby restaurant at 6pm. Thanks, Colin R

1 0

CFP TASE 2008
by Huibiao Zhu 13 Nov '07

13 Nov '07

(Apologies if you have already received this message.) TASE 2008 2nd IEEE&IFIP Symposium on Theoretical Aspects of Software Engineering Nanjing, China June 17-19, 2008 http://seg.nju.edu.cn/tase08 Large scale software systems and Internet are of growing concern to academia and industry. This poses new challenges to the various aspects of software engineering, for instance, the reliability of software development, web-oriented software architecture and aspect & object-orientation techniques. As a result, new concepts and methodologies are required to enhance the development of software engineering from theoretical aspects. TASE 2008 is a forum for researchers from academia, industry and government to present ideas, results, and ongoing research on theoretical advances in software engineering. TASE 2008 is the second in a series of conference, sponsored by IEEE CS and IFIP. The first TASE conference was held in Shanghai, China, in June 2007. Topics of Interest: Authors are invited to submit high quality technical papers describing original and unpublished work in all theoretical aspects of software engineering. Topics of interest include, but are not limited to: * Requirements Engineering * Specification and Validation * Software Testing * Component-based Development * Model Checking for Software * Software Processes and Workflows * Software Frameworks and Middleware * Software Architectures and Design * Software safety and reliability * Reverse Engineering and Software Maintenance * Aspect and Objected �Corientation Techniques * Embedded and Real-time Software * Service-oriented Computing and Web Services * Model-driven Development * Coordination and Feature Interaction * Parallel and Distributed Computing * Logics of Programs * Program Analysis * Semantics and Design of Programming Languages * Type Theory Submission Guidelines: Authors should submit and register their paper through our web-interface at: http://seg.nju.edu.cn/tase08/submit by January 28, 2008. Submissions must not have been published or be concurrently considered for publication elsewhere. All submissions will be reviewed by at least three members of the program committee. They will be judged on the basis of originality, contribution to the field, technical and presentation quality, and relevance to the conference. The proceedings of the conference will be published by the IEEE Computer Society Press. Papers must be written in English and not exceed 10 pages in IEEE format. Instructions for authors are available at http://computer.org/cspress/instruct.htm. Latex document classes can be downloaded from the website at ftp://pubftp.computer.org/Press/Outgoing/proceedings/. Important Dates: * January 21, 2008: Title and abstract submission deadline * January 28, 2008: Paper submission deadline * March 10, 2008: Acceptance/rejection notification * March 23, 2008: Camera-ready version due * June 17-19, 2008: TASE 2008 Organization: General Co-Chairs: Jifeng He, East China Normal University, China Jian Lu, Nanjing University, China Program Co-chairs: Jim Davies, Oxford University, UK �� Xuandong Li, Nanjing University, China Local Organization Chair: Linzhang Wang, Nanjing University, China Program Committee: Bernhard Aichernig (Graz University of Technology, Austria) Keijiro Araki (Kyzushu University, Japan) Farhad Arbab (CWI and Leiden University, The Netherlands) Jonathan Bowen (Museophile Limited, UK) Michael Butler (University of Southampton, UK) Ana Cavalcanti (University of York, UK) Jim Davies (Oxford University, UK) Geoff Dromey (Griffith University, Australia) Jin Song Dong (National University of Singapore, Singapore) Zhenhua Duan (Xi��dian University, China) Colin Fidge (Queensland University of Technology, Australia) Dieter Gollmann (Hamburg University of Technology, Germany) Kung-Kiu Lau (Manchester University, UK) Jing Liu (East China Normal University, China) Shaoying Liu (Hosei University, Japan) Zhiming Liu (UNU/IIST, Macau, China) Annabelle Mclver (Macquarie University, Australia) Hong Mei (Peking University, China) Huaikou Miao (Shanghai University, China) Shankar Natarajan (SRI International, USA) Nimal Nissanke (London South Bank University, UK) Geguang Pu((East China Normal University, China)) Shengchao Qin (Durham University, UK) Zongyan Qiu (Peking University, China) Zhong Shao (Yale University, USA) Joseph Sifakis (Verimag, France) Zhengdong Su (University of California at Davis, USA) Margus Veanes (Microsoft, USA) Sergiy Vilkomir (University of Limerick, Ireland) Farn Wang (National Taiwan University, Taiwan) Ji Wang (Changsha Institute of Technology, China) Linzhang Wang(Nanjing University, China) Heike Wehrheim (University of Paderborn, Germany) Jim Woodcock (University of York, UK) Dianxiang Xu(North Dakota State University, USA) Wang Yi (Uppsala University, Sweden) Gianluigi Zavattaro (University of Bologna, Italy) Jian Zhang (Institute of Software, China) Jianhua Zhao (Nanjing University, China) Huibiao Zhu (East China Normal University, China) Steering Program Committee Michael Hinchey(Chair), USA Keijiro Araki, Japan Jifeng He, China Zhiming Liu, Macau Mike Reed, Macau Huibiao Zhu, China Keynote Speakers Edmund M. Clarke (Carnegie Mellon University) Joost-Pieter Katoen (RWTH Aachen University)

1 0