May 2014 - Haskell-Cafe

Haskell Weekly News: Issue 294
by Daniel Santa Cruz 07 May '14

07 May '14

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OCL 2014: First Call for Papers
by Achim D. Brucker 07 May '14

07 May '14

(Apologies for duplicates) CALL FOR PAPERS 14th International Workshop on OCL and Textual Modeling Applications and Case Studies (OCL 2014) Co-located with ACM/IEEE 17th International Conference on Model Driven Engineering Languages and Systems (MODELS 2014) September 28-30 (tbc), 2014, VALENCIA, SPAIN http://www.software.imdea.org/OCL2014/ Modeling started out with UML and its precursors as a graphical notation. Such visual representations enable direct intuitive capturing of reality, but some of their features are difficult to formalize and lack the level of precision required to create complete and unambiguous specifications. Limitations of the graphical notations encouraged the development of text-based modeling languages that either integrate with or replace graphical notations for modeling. Typical examples of such languages are OCL, textual MOF, Epsilon, and Alloy. Textual modeling languages have their roots in formal language paradigms like logic, programming and databases. The goal of this workshop is create a forum where researchers and practitioners interested in building models using OCL or other kinds of textual languages can directly interact, report advances, share results, identify tools for language development, and discuss appropriate standards. In particular, the workshop will encourage discussions for achieving synergy from different modeling language concepts and modeling language use. The close interaction will enable researchers and practitioners to identify common interests and options for potential cooperation. Topics of interest include (but are not limited to) =================================================== - Mappings between textual modeling languages and other languages/formalisms - Algorithms, evaluation strategies and optimizations in the context of textual modeling languages for -- validation, verification, and testing, -- model transformation and code generation, -- metamodeling and DSLs, and -- query and constraint specifications - Alternative graphical/textual notations for textual modeling languages - Evolution, transformation and simplification of textual modeling expressions - Libraries, templates and patterns for textual modeling languages - Complexity results for textual modeling languages - Quality models and benchmarks for comparing and evaluating textual modeling tools and algorithms - Successful applications of textual modeling languages - Case studies on industrial applications of textual modeling languages - Experience reports -- usage of textual modeling languages and tools in complex domains, -- usability of textual modeling languages and tools for end-users - Empirical studies about the benefits and drawbacks of textual modeling languages - Innovative textual modeling tools - Comparison, evaluation and integration of modeling languages - Correlation between modeling languages and modeling tasks This year, we particularly encourage submissions describing applications and case studies of textual modeling as well as test suites and benchmark collections for evaluating textual modeling tools. Venue ===== The workshop will be organized as a part of MODELS 2014 Conference in Valencia, Spain. It continues the series of OCL workshops held at UML/MODELS conferences: York (2000), Toronto (2001), San Francisco (2003), Lisbon (2004), Montego Bay (2005), Genova (2006), Nashville (2007), Toulouse (2008), Denver (2009), Oslo (2010), Zurich (2011, at the TOOLs conference), 2012 in Innsbruck, and 2013 in Miami. Similar to its predecessors, the workshop addresses both people from academia and industry. The aim is to provide a forum for addressing integration of OCL and other textual modeling languages, as well as tools for textual modeling, and for disseminating good practice and discussing the new requirements for textual modeling. Workshop Format =============== The workshop will include short (about 15 min) presentations, parallel sessions of working groups, and sum-up discussions. Submissions =========== Two types of papers will be considered: * short papers (6 pages) and * full papers (10 pages) in LNCS format. Submissions should be uploaded to EasyChair (https://www.easychair.org/conferences/?conf=ocl2014) The program committee will review the submissions (minimum 2 reviews per paper, usually 3 reviews) and select papers according to their relevance and interest for discussions that will take place at the workshop. Accepted papers will be published online in a pre-conference edition of CEUR (http://www.ceur-ws.org) Authors of selected papers will be invited to submit an extended version of their workshop paper to a special issue of the Electronic Communications of the EASST (http://journal.ub.tu-berlin.de/eceasst) Important Dates =============== Submission of papers: July 11, 2014 Notification: August 8, 2014 Workshop date: one day during September 28-30, 2014 Organizers ========== Achim D. Brucker, SAP AG, Germany Carolina Dania, IMDEA Software Institute, Madrid, Spain Geri Georg, Colorado State University, Fort Collins, Colorado, USA Martin Gogolla, University of Bremen, Germany Programme Committee (partly confirmation pending) =================== Michael Altenhofen, SAP AG, Germany Thomas Baar, University of Applied Sciences Berlin, Germany Mira Balaban, Ben-Gurion University of the Negev, Israel Tricia Balfe, Nomos Software, Ireland Fabian Buettner, Ecole des Mines de Nantes, France Achim D. Brucker, SAP AG, Germany Jordi Cabot, INRIA-Ecole des Mines de Nantes, France Yoonsik Cheon, University of Texas, USA Dan Chiorean, Babes-Bolyai University, Romania Robert Clariso, Universitat Oberta de Catalunya, Spain Tony Clark, Middlesex University, UK Manuel Clavel, IMDEA Software Institute, Madrid, Spain Carolina Dania, IMDEA Software Institute, Madrid, Spain Birgit Demuth, Technische Universitat Dresden, Germany Marina Egea, Atos Research, Madrid, Spain Geri Georg, Colorado State University, Fort Collins, Colorado, USA Martin Gogolla, University of Bremen, Germany Pieter Van Gorp, Eindhoven University of Technology, The Netherlands Heinrich Hussmann, LMU Munchen, Germany Tihamer Levendovszky, Vanderbilt University, USA Shahar Maoz, Tel Aviv University, Israel Istvan Rath, Budapest University of Technology and Economics, Hungary Bernhard Rumpe, RWTH Aachen, Germany Shane Sendall, Snowie Research SA, Switzerland Michael Wahler, ABB Switzerland Ltd Corporate Research, Switzerland Claas Wilke, Technische Universitat Dresden, Germany Edward Willink, Willink Transformations Ltd., UK Burkhart Wolff, Univ Paris-Sud, France Steffen Zschaler, King’s College, London, UK -- Dr. Achim D. Brucker, SAP AG, Vincenz-Priessnitz-Str. 1, D-76131 Karlsruhe Phone: +49 6227 7-52595, http://www.brucker.ch/

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I would like to add haskell-russian@ mailing list to "User groups" wiki page
by Alexander Alexeev 07 May '14

07 May '14

Hello. Could someone add https://groups.google.com/forum/#!aboutgroup/haskell-russian ... to this wiki page http://www.haskell.org/haskellwiki/User_groups#Russia ... please? Or I could do it by myself if someone would create me an account at Haskell Wiki. Username I would like to have - eax (like @ Hackege). -- Best regards, Alexander Alexeev http://eax.me/

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Splicious is now accepting applications for alpha user trials
by Greg Meredith 06 May '14

06 May '14

Dear Haskellians and CurriedOnes, Splicious is now accepting applications for alpha user trials<http://www.splicious.net/> . To learn more about splicious, apart from that it is written in a higher-kinded functional language and makes extremely cool use of delimited continuations, please check out these links. - splicious and distributed identity<https://www.youtube.com/watch?v=Tz2pmVGgrG4> - splicious, BitCoin, content creation, curation, and sharing<https://www.youtube.com/watch?v=f700b6IHZcc> - Vlad Patryshev's review of splicious<https://www.youtube.com/watch?v=nRmu9-AL2OM> - The specialK white paper<https://docs.google.com/document/d/1aM5OIJWOyW89rHdUg6d9-YVbItdtxxiosP_fXZQ…> - A link to our crowd funding site<http://www.rockethub.com/projects/42500-splicious> Love to all, --greg -- L.G. Meredith Managing Partner Biosimilarity LLC 1219 NW 83rd St Seattle, WA 98117 +1 206.650.3740 http://biosimilarity.blogspot.com

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Cabal exit codes when work to be done
by Andrew Cowie 06 May '14

06 May '14

Is there a way to run e.g. `cabal install --only-dependencies` and have it return a non-zero exit code if, for instance, there IS something to do? I tried `--dry-run` but the exit code is still 0 if something is missing. [or have it return non-zero if there isn't work to do, or...] AfC Sydney

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Questions about Functor, Applicative, Monad
by Corentin Dupont 05 May '14

05 May '14

Hi everybody! Two questions in one: - When you define and instance of a Monad, why don't you get the Applicative and Functor instances for free? I seem that you can mechanically write them. - Do you have examples of things that are Functors but not Applicative? Applicative but not Monads? Tchuss Corentin

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extensible records - Vinyl - alternatives?
by Peter Althainz 05 May '14

05 May '14

Dear All, I'm searching a handsome library for handling large amounts of configuration data in a flexible manner. So to speak I want to use some kind of inheritance of data fields. I think this is where the extensible records discussion is a proper description of my use case. I've found 2 libraries making this work, so far: HList Vinyl I currently prefer Vinyl due to the complex types in HList, lens compatibiliy, named labels. (I love the HList and OOHaskel papers, but for practical use, I currently prefer Vinyl). What do you think, what is the best way nowadays to use extensible records? Is Vinyl a good choice from your point of view? regards Peter

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ANN: hsqml-0.3.0.0 supports Qt 5
by Robin KAY 05 May '14

05 May '14

Dear All, I would like to announce version 0.3.0.0 of the HsQML graphics library, a Haskell binding to the Qt Quick framework. The library allows you to write graphical applications where the front-end is written in Qt Quick's QML language (incorporating JavaScript) and the back-end is written in Haskell. The two layers are coupled together via a facility to define custom JavaScript objects through which QML code can call into Haskell and vice versa. Documentation including a brief tutorial is available on my web-site [1]. HsQML requires an installation of Qt 5 (including Qt Quick) present on your path. This is the first release to support Qt 5 and it has been a much requested feature. Several other new features are also introduced in this release, including support for marshalling lists and signalling property notifications. For more information, please see the release announcement [2]. The release is available for download from Hackage [3] along with a demo application implementing Nine Men's Morris [4] and some other sample programs [5]. Linux, Windows, and Mac OS platforms should all be supported. [1] http://www.gekkou.co.uk/software/hsqml [2] http://blog.gekkou.co.uk/2014/05/hsqml-0300-released-now-with-qt-5.html [3] http://hackage.haskell.org/package/hsqml-0.3.0.0 [4] http://hackage.haskell.org/package/hsqml-demo-morris-0.3.0.0 [5] http://hackage.haskell.org/package/hsqml-demo-samples-0.3.0.0 Regards, -- Robin KAY

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Quick question on Lens
by Corentin Dupont 04 May '14

04 May '14

Hello! I have a record like this: data A = { _bs :: [B]} funcA :: State A () funcA = bs ??? funcB funcB :: State B () funcB = ... What lens operator should I use instead of ???, to update all my Bs? Cheers, Corentin

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Experimenting a new plotting library
by Kai Zhang 04 May '14

04 May '14

Hi cafe, I'm experimenting a new plotting library which makes use of the API of diagrams. I decided to start this work, because: 1. There is few plotting library written in pure Haskell 2. Haskell-chart, one of the most featured library, is hard to extend and there is no straightforward way to compose or modify the plots generated by this library. I had some ideas for the new library. You can get some feeling from here: https://github.com/kaizhang/haskell-plot I'm still relatively new to haskell and don't have much experience in making plots either. Hopefully I can get some suggestions from you guys and improve my programming skills through this process.

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