May 2013 - Haskell - Haskell.org

Invitation to connect on LinkedIn
by Daniel Díaz Casanueva 15 May '13

15 May '13

LinkedIn ------------ Daniel Díaz Casanueva requested to add you as a connection on LinkedIn: ------------------------------------------ Adrian, I'd like to add you to my professional network on LinkedIn. - Daniel Accept invitation from Daniel Díaz Casanueva http://www.linkedin.com/e/-y1615u-hgr1efjt-n/A5eR2FIG5M9-4jk43rQ4JqtVY2yX2K… View profile of Daniel Díaz Casanueva http://www.linkedin.com/e/-y1615u-hgr1efjt-n/rso/255311896/LIky/name/144943… ------------------------------------------ You are receiving Invitation emails. This email was intended for Adrian Borucki. Learn why this is included: http://www.linkedin.com/e/-y1615u-hgr1efjt-n/plh/http%3A%2F%2Fhelp%2Elinked… (c) 2012, LinkedIn Corporation. 2029 Stierlin Ct, Mountain View, CA 94043, USA.

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recursion patterns?
by 7stud 15 May '13

15 May '13

Well, my question does not meet the standards for a question at stackoverflow: (I am a haskell beginner) This example is from LYAH: import System.Random finiteRandoms :: (RandomGen g, Random a, Num n) => n -> g -> ([a], g) finiteRandoms 0 gen = ([], gen) finiteRandoms n gen = let (value, newGen) = random gen (restOfList, finalGen) = finiteRandoms (n-1) newGen in (value:restOfList, finalGen) Looking at that function, I find it impossible to understand how that recursion works. I have to pull out a pencil and paper to figure it out. If I was given the task of writing that function, I would write it like this: import System.Random finiteRands :: (RandomGen g, Random a) => Int -> g -> [a] finiteRands n gen = finiteRands' n gen [] finiteRands' :: (RandomGen g, Random a) => Int -> g -> [a] -> [a] finiteRands' 0 _ acc = acc finiteRands' n gen acc = let (rand_num, new_gen) = random gen in finiteRands' (n-1) new_gen (rand_num:acc) To me, it makes the function(s) simplistic to understand. Is the first solution a known 'design pattern' in recursion? The first solution: import System.Random finiteRandoms :: (RandomGen g, Random a, Num n) => n -> g -> ([a], g) finiteRandoms 0 gen = ([], gen) finiteRandoms n gen = let (value, newGen) = random gen (restOfList, finalGen) = finiteRandoms (n-1) newGen in (value:restOfList, finalGen) seems to operate a bit like foldr: the recursion spins to the base case, and the base case's return value, ([], gen), is passed back through all the function calls. Each function call modifies the tuple (the in clause) before returning it to the previous function call. Is one solution more efficient than the other? I believe my solution is tail recursive, but it's my understanding that compilers can now optimize just about anything into tail recursion. Thanks.

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ACM SIGPLAN Erlang Workshop 2013 Second Call For Papers
by Laura M. Castro 14 May '13

14 May '13

Hello, Please find below the Second Call for Papers for the Twelfth ACM SIGPLAN Erlang Workshop. Apologies for any duplicates you may receive. CALL FOR PAPERS ================= Twelfth ACM SIGPLAN Erlang Workshop ----------------------------------------------------------- Boston, Massachusetts, September 28, 2013 (tentative date, subject to change) Satellite event of the 18th ACM SIGPLAN International Conference on Functional Programming (ICFP 2013) September 25-27, 2013 Erlang is a concurrent, distributed functional programming language aimed at systems with requirements of massive concurrency, soft real time response, fault tolerance, and high availability. It has been available as open source for 15 years, creating a community that actively contributes to its already existing rich set of libraries and applications. Originally created for telecom applications, its usage has spread to other domains including e-commerce, banking, databases, and computer telephony and messaging. Erlang programs are today among the largest applications written in any functional programming language. These applications offer new opportunities to evaluate functional programming and functional programming methods on a very large scale and suggest new problems for the research community to solve. This workshop will bring together the open source, academic, and industrial programming communities of Erlang. It will enable participants to familiarize themselves with recent developments on new techniques and tools tailored to Erlang, novel applications, draw lessons from users' experiences and identify research problems and common areas relevant to the practice of Erlang and functional programming. We invite three types of submissions. 1. Technical papers describing language extensions, critical discussions of the status quo, formal semantics of language constructs, program analysis and transformation, virtual machine extensions and compilation techniques, implementations and interfaces of Erlang in/with other languages, and new tools (profilers, tracers, debuggers, testing frameworks, etc.). The maximum length for technical papers is restricted to 12 pages. 2. Practice and application papers describing uses of Erlang in the "real-world", Erlang libraries for specific tasks, experiences from using Erlang in specific application domains, reusable programming idioms and elegant new ways of using Erlang to approach or solve a particular problem. The maximum length for the practice and application papers is restricted to 12 pages. Note that this is a maximum length; we welcome shorter papers also, and the program committee will evaluate all papers on an equal basis independent of their lengths. 3. Poster presentations describing topics related to the workshop goals. Each includes a maximum of 2 pages of the abstract and summary. Presentations in this category will be given an hour of shared simultaneous demonstration time. Workshop Chair ----------------------- Steve Vinoski, Basho Technologies, USA Program Chair ------------------- Laura M. Castro, University of A Coruña, Spain Program Committee ----------------------------- (Note: the Workshop and Program Chairs are also committee members) Lars-Ake Fredlund, Universidad Politécnica de Madrid, Spain Kevin Hammond, University of St. Andrews, UK Torben Hoffman, Erlang Solutions Limited, UK Zoltán Horváth, Eötvös Loránd University, Hungary Kenneth Lundin, Ericsson AB, Sweden Mickaël Rémond, ProcessOne, France Kenji Rikitake, Basho Japan KK, Japan Simon Thompson, University of Kent, UK Important Dates ----------------------- Submission deadline: Fri June 14, 2013 Author notification: Thu July 11, 2013 Final submission for the publisher: Thu July 25, 2013 Workshop date (tentative, subject to change): September 28, 2013 Instructions to authors -------------------------------- Papers must be submitted online via EasyChair (via the "Erlang2013" event). The submission page is https://www.easychair.org/conferences/?conf=erlang2013 Submitted papers should be in portable document format (PDF), formatted using the ACM SIGPLAN style guidelines. Each submission must adhere to SIGPLAN's republication policy. Violation risks summary rejection of the offending submission. Accepted papers will be published by the ACM and will appear in the ACM Digital Library. Paper submissions will be considered for poster submission in the case they are not accepted as full papers. Venue & Registration Details ------------------------------------------ For registration, please see the ICFP 2013 web site at: http://icfpconference.org/icfp2013/ Related Links -------------------- ICFP 2013 web site: http://www.icfpconference.org/icfp2013/ Past ACM SIGPLAN Erlang workshops: http://www.erlang.org/workshop/ Open Source Erlang: http://www.erlang.org/ EasyChair submission site: https://www.easychair.org/account/signin.cgi?conf=erlang2013 Author Information for SIGPLAN Conferences: http://www.sigplan.org/authorInformation.htm -- Laura M. Castro

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Assistant Professor in Software Systems
by Matthew Hennessy 14 May '13

14 May '13

Assistant Professor in Software Systems University of Dublin, Trinity College Discipline of Software Systems, School of Computer Science and Statistics Post Status: Permanent Job Ref: 030223 Salary: This appointment will be made on the Department of Education and Skills Lecturer Salary Scale in line with current government pay policy and will be capped at a maximum Point 8. Closing Date: 12 noon on Monday, 10th June 2013 The post is tenable from 1 September, 2013. The Discipline of Software Systems in the School of Computer Science and Statistics is seeking to appoint an Assistant Professor in Software Systems. The Discipline is looking for an exceptional person with a proven track record in research in the field of Software Systems, preferably with research expertise in algorithms, data-structures and compilers. A significant series of publications in internationally recognised journals and conferences is expected of candidates. The successful applicant will have a primary degree and PhD in computer science or a related discipline, and will have a genuine commitment to teaching all aspects of software at both undergraduate and postgraduate levels. Enthusiasm for the development and delivery of novel teaching modules on algorithms, data-structures and compilers is also required. For more details of the post, and how to apply see https://jobs.tcd.ie/ Informal enquiries are welcome and candidates may e-mail Professor Matthew Hennessy (matthew.hennessy(a)cs.tcd.ie)

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ANNOUNCE: Haskell Communities and Activities Report (24th ed., May 2013)
by Janis Voigtländer 11 May '13

11 May '13

On behalf of all the contributors, I am pleased to announce that the Haskell Communities and Activities Report (24th edition, May 2013) is now available in PDF and HTML formats: http://haskell.org/communities/05-2013/report.pdf http://haskell.org/communities/05-2013/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 2013: target deadline for contributions to the November 2013 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>

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Call for talk proposals: HOPE'13 (Workshop on Higher-Order Programming with Effects, affiliated with ICFP'13)
by Hongseok Yang 11 May '13

11 May '13

---------------------------------------------------------------------- CALL FOR TALK PROPOSALS HOPE 2013 The 2nd ACM SIGPLAN Workshop on Higher-Order Programming with Effects September 28, 2013 Boston, Massachusetts (the day after ICFP 2013) http://hope2013.mpi-sws.org ---------------------------------------------------------------------- HOPE 2013 aims at bringing together researchers interested in the design, semantics, implementation, and verification of higher-order effectful programs. It will be *informal*, consisting of invited talks, contributed talks on work in progress, and open-ended discussion sessions. --------------------- Goals of the Workshop --------------------- A recurring theme in many papers at ICFP, and in the research of many ICFP attendees, is the interaction of higher-order programming with various kinds of effects: storage effects, I/O, control effects, concurrency, etc. While effects are of critical importance in many applications, they also make it hard to build, maintain, and reason about one's code. Higher-order languages (both functional and object-oriented) provide a variety of abstraction mechanisms to help "tame" or "encapsulate" effects (e.g. monads, ADTs, ownership types, typestate, first-class events, transactions, Hoare Type Theory, session types, substructural and region-based type systems), and a number of different semantic models and verification technologies have been developed in order to codify and exploit the benefits of this encapsulation (e.g. bisimulations, step-indexed Kripke logical relations, higher-order separation logic, game semantics, various modal logics). But there remain many open problems, and the field is highly active. The goal of the HOPE workshop is to bring researchers from a variety of different backgrounds and perspectives together to exchange new and exciting ideas concerning the design, semantics, implementation, and verification of higher-order effectful programs. We want HOPE to be as informal and interactive as possible. The program will thus involve a combination of invited talks, contributed talks about work in progress, and open-ended discussion sessions. There will be no published proceedings, but participants will be invited to submit working documents, talk slides, etc. to be posted on this website. ----------------------- Call for Talk Proposals ----------------------- We solicit proposals for contributed talks. Proposals should be at most 2 pages, in either plain text or PDF format, and should specify how long a talk the speaker wishes to give. By default, contributed talks will be 30 minutes long, but proposals for shorter or longer talks will also be considered. Speakers may also submit supplementary material (e.g. a full paper, talk slides) if they desire, which PC members are free (but not expected) to read. We are interested in talks on all topics related to the interaction of higher-order programming and computational effects. Talks about work in progress are particularly encouraged. If you have any questions about the relevance of a particular topic, please contact the PC chairs at the address hope2013 AT mpi-sws.org. Deadline for talk proposals: June 14, 2013 (Friday) Notification of acceptance: July 28, 2013 (Sunday) Workshop: September 28, 2013 (Saturday) The submission website is now open: https://www.easychair.org/conferences/?conf=hope2013 --------------------- Workshop Organization --------------------- Program Co-Chairs: Derek Dreyer (MPI-SWS, Germany) Hongseok Yang (University of Oxford) Program Committee: Anindya Banerjee (IMDEA Software Institute) Lars Birkedal (Aarhus University) Aquinas Hobor (National University of Singapore) Chung-Kil Hur (Microsoft Research Cambridge) Patricia Johann (Appalachian State University) Matthew Might (University of Utah) Peter Mueller (ETH Zurich) Brigitte Pientka (McGill University) Zhong Shao (Yale)

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ANN: strict-base-types-0.1
by Simon Meier 11 May '13

11 May '13

Dear fellow haskellers, the strict-base-types package makes it easy to get rid of the unnecessary laziness (and the resulting space leaks) in your applications; i.e., no more data AppState = AppState { _field :: !(Maybe T.Text) , ... } as the alternative import qualified Data.Maybe.Strict as S data AppState = AppState { _field :: !(S.Maybe T.Text) , ... } is now equally cheap. See http://hackage.haskell.org/package/strict-base-types-0.1 for a full explanation of the functionality provided by this package. happy hacking, Simon

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Formal Methods/Functional programming job position at Intel
by Levent Erkok 08 May '13

08 May '13

Our formal methods team at Intel has a full-time position available that I think would be a good fit for functional programming and formal methods enthusiasts. I'm including the description below. Do not hesitate to contact me if you've any questions, or just want to talk about it in general. To apply for the position, please visit: http://www.intel.com/jobs/jobsearch/index.htm, and in the "advanced search" area enter the job number: 709631. Thanks, -Levent. Job Description *Formal Methods & Validation Architect* *-* *709631* Description If you're interested in products going into future super computer markets then the Intel® Many Integrated Core (Intel® MIC) Hardware Engineering Group is the place for you! We design and validate silicon chips with many Intel cores integrated inside being used in high performance computing architectures. In this position you will work as part of the pre-silicon formal methods, tools, and verification team to support a continued high quality of the future Intel many core processor products. You will work together with Intel's formal verification and validation community, the Formal Verification Center of Expertise (FV CoE) in a team of experts in formal methods and AV Validation. Your specific responsibilities will include defining formal verification (FV) test plans as well as Cluster Test Environment (CTE) based test plans for dynamic simulation validation (DV). The goal is to help optimize a combined use of FV and CTE based validation techniques (DV) and contribute to an increasing use of formal methods at Intel. Based on the test plans you will write properties in formal language, and prove the properties using our model checkers and theorem proving tools. You will also write CTE based test cases and coverage plans. Your area of strength may currently lie within either FV or DV with strong skills rooted in software development. But through your skills and work, you will become an expert in both formal methods and validation technologies. You will interact very closely with design teams, and other validation teams, as well as with Intel's internal R&D groups that continue to improve and develop formal method and verification tools. You must be able to communicate effectively with various technical groups and coordinate activities amongst those groups.

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CfP Workshop Haskell and Rewriting Techniques (Deadline: May 21)
by Johannes Waldmann 08 May '13

08 May '13

final call for papers (note: extended deadline) ================================================== Rewriting is the science of replacing equals by equals and thus a very powerful method for dealing with equations. There are strong connections between Haskell programming and rewriting. Therefore, we announce a new workshop, International Workshop on Haskell And Rewriting Techniques (HART 2013) http://www.imn.htwk-leipzig.de/HART2013/ to be held on June 27, in conjunction with RDP 2013, in Eindhoven. (RDP contains RTA, the main rewriting conference.) We plan a half day of discussions, in an informal setting, on how Haskell and rewriting techniques and theories can cross-fertilize each other. Topics of interest are, for example, equational reasoning and other rewriting techniques for program verification and analysis; lambda calculi and type systems for functional programs and higher order rewriting systems; rewriting of type expressions in the type checker; rewriting of programs by refactoring tools, optimizers, code generators; execution of programs as a form of graph rewriting; template Haskell, introducing a rewriting-like macro language into the compilation process. This list of topics is non-exclusive. If you have a contribution that connects Haskell and rewriting, then submit. When in doubt, contact a member of the PC. Program committee: Alcino Cunha (U Minho) Jürgen Giesl (RWTH Aachen) Andy Gill (U of Kansas) Johan Jeuring (U Utrecht) Keisuke Nakano (UEC Tokyo) Kristoffer H Rose (IBM Watson) (co-chair) Christian Sternagel (JAIST) Janis Voigtländer (U Bonn) Johannes Waldmann (HTWK Leipzig) (co-chair) Dates: May 21: deadline for submissions May 28: notification of acceptance June 27: workshop Submission and Proceedings: Two categories of submissions are invited: Extended abstracts. Presenting original research, and also preliminary reports of work in progress. Will be included in the proceedings. Presentation-only papers. Describing work recently published or submitted. Will not be included in the proceedings. Papers should be at most 5 pages in length, and should use the easychair.cls style. Submission is handled through the EasyChair HART2013 page, https://www.easychair.org/conferences/?conf=hart2013 In line with the informal style of the workshop, the reviewing of submissions will be light. When accepting and scheduling presentations, preference will be given to original research. Proceedings will be made available electronically at the workshop.

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PPDP 2013: 2nd Call for Papers
by Tom Schrijvers 07 May '13

07 May '13

===================================================================== 2nd Call for papers 15th International Symposium on Principles and Practice of Declarative Programming PPDP 2013 Special Issue of Science of Computer Programming (SCP) Madrid, Spain, September 16-18, 2013 (co-located with LOPSTR 2013) http://users.ugent.be/~tschrijv/PPDP2013/ ====================================================================== EXTENDED SUBMISSION DEADLINE: JUNE 13, 2013 PPDP 2013 is a forum that brings together researchers from the declarative programming communities, including those working in the logic, constraint and functional programming paradigms, but also embracing a variety of other paradigms such as visual programming, executable specification languages, database languages, and knowledge representation languages. The goal is to stimulate research in the use of logical formalisms and methods for specifying, performing, and analysing computations, including mechanisms for mobility, modularity, concurrency, object-orientation, security, verification and static analysis. Papers related to the use of declarative paradigms and tools in industry and education are especially solicited. Topics of interest include, but are not limited to: * Functional programming * Logic programming * Answer-set programming * Functional-logic programming * Declarative visual languages * Constraint Handling Rules * Parallel implementation and concurrency * Monads, type classes and dependent type systems * Declarative domain-specific languages * Termination, resource analysis and the verification of declarative programs * Transformation and partial evaluation of declarative languages * Language extensions for security and tabulation * Probabilistic modelling in a declarative language and modelling reactivity * Memory management and the implementation of declarative systems * Practical experiences and industrial application This year the conference will be co-located with the 23nd International Symposium on Logic-Based Program Synthesis and Transformation (LOPSTR 2013) and held in cooperation with ACM SIGPLAN. The conference will be held in Madrid, Spain. Previous symposia were held at Leuven (Belgium), Odense (Denmark), Hagenberg (Austria), Coimbra (Portugal), Valencia (Spain), Wroclaw (Poland), Venice (Italy), Lisboa (Portugal), Verona (Italy), Uppsala (Sweden), Pittsburgh (USA), Florence (Italy), Montreal (Canada), and Paris (France). Papers must describe original work, be written and presented in English, and must not substantially overlap with papers that have been published or that are simultaneously submitted to a journal, conference, or workshop with refereed proceedings. Work that already appeared in unpublished or informally published workshop proceedings may be submitted (please contact the PC chair in case of questions). Proceedings will be published in the ACM International Conference Proceedings Series. After the symposium, a selection of the best papers will be invited to extend their submissions in the light of the feedback solicited at the symposium. The papers are expected to include at least 30% extra material over and above the PPDP version. Then, after another round of reviewing, these revised papers will be published in a special issue of SCP with a target publication date by Elsevier of 2014. Important Dates Abstract Submission: June 10, 2013 Paper submission: June 13, 2013 Notification: July 18, 2013 Camera-ready: August 4, 2013 Symposium: September 16-18, 2013 Invites for SCP: October 2, 2013 Submission of SCP: December 11, 2013 Notification from SCP: February 22, 2014 Camera-ready for SCP: March 14, 2014 Authors should submit an electronic copy of the paper (written in English) in PDF. Each submission must include on its first page the paper title; authors and their affiliations; abstract; and three to four keywords. The keywords will be used to assist us in selecting appropriate reviewers for the paper. Papers should consist of no more than 12 pages, formatted following the ACM SIG proceedings template (option 1). The 12 page limit must include references but excludes well-marked appendices not intended for publication. Referees are not required to read the appendices, and thus papers should be intelligible without them. Program Committee Sergio Antoy Portland State University, USA Manuel Carro IMDEA Software Institute, Spain Iliano Cervesato Carnegie Mellon University, Qatar Agostino Dovier Universita degli Studi di Udine, Italy Maria Garcia de la Banda Monash University, Australia Ralf Hinze University of Oxford, UK Yukiyoshi Kameyama University of Tsukuba, Japan Oleg Kiselyov USA Yanhong Annie Liu State University of New York at Stony Brook, USA Stefan Monnier Universite de Montreal, Canada Alan Mycroft University of Cambrige, UK Bruno C. d. S. Oliveira National University of Singapore, Singapore Alberto Pettorossi Universita di Roma Tor Vergata, Italy Enrico Pontelli New Mexico State University, USA Kristoffer Rose IBM Research, USA Sukyoung Ryu KAIST, South Korea Vitor Santos Costa University of Porto, Portugal Torsten Schaub University Potsdam, Germany Tom Schrijvers Ghent University, Belgium Martin Sulzmann Hochschule Karlsruhe, Germany Wouter Swierstra Universiteit Utrecht, The Netherlands Tarmo Uustalu Institute of Cybernetics, Estonia Janis Voigtlaender University of Bonn, Germany Meng Wang Chalmers University of Technology, Sweden Jan Wielemaker Universiteit van Amsterdam, The Netherlands Program Chair Tom Schrijvers Department of Applied Mathematics and Computer Science Ghent University 9000 Gent, Belgium General Chair Ricardo Pena Facultad de Informatica Universidad Complutense de Madrid 28040 Madrid, Spain

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