November 2011 - Haskell-Cafe

Fwd: XML modification
by Dmitry Olshansky 23 Nov '11

23 Nov '11

Personally I prefer xml-enumerator. You can work with xml-stream or with DOM through cursor (like XPath). I think that in your case working with stream is preferrable. You can just make an Enumeratee like >import qualified Data.Enumerator.List as EL > myEnum = EL.map f > where > f (EventBeginElement n ats) = ... -- parse attributes > f e = e 2011/11/23 Andrew Coppin <andrewcoppin(a)btinternet.com> > Hi guys. > > I've got a folder with about 80 XML files in it. I want to take each file > and make specific modifications to it. (Mostly just finding specific > attributes and changing their values to make then all consistent.) > > Now I guess it wouldn't take me /that/ long to code something from > scratch. But does anybody have a better suggestion for tools or libraries > that might be useful? > > ______________________________**_________________ > Haskell-Cafe mailing list > Haskell-Cafe(a)haskell.org > http://www.haskell.org/**mailman/listinfo/haskell-cafe<http://www.haskell.org/mailman/listinfo/haskell-cafe> >

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PEPM'12 Call for participation
by Simon Thompson 23 Nov '11

23 Nov '11

ACM SIGPLAN 2012 Workshop on Partial Evaluation and Program Manipulation http://www.program-transformation.org/PEPM12 January 23-24, 2012. Philadelphia, PA, USA (co-located with POPL'12) Call For Participation Online registration is open at https://regmaster3.com/2012conf/POPL12/register.php Early registration deadline is December 24, 2011 The PEPM Symposium/Workshop series brings together researchers and practitioners working in the broad area of program transformation, which spans from refactoring, partial evaluation, supercompilation, fusion and other metaprogramming to model-driven development, program analyses including termination, inductive programming, program generation and applications of machine learning and probabilistic search. PEPM focuses on techniques, supporting theory, tools, and applications of the analysis and manipulation of programs. In addition to the presentations of regular research papers, the PEPM program includes tool demonstrations and `short paper' presentations of exciting if not fully polished research. PEPM has established a Best Paper award. The winner will be announced at the workshop. INVITED TALKS Compiling Math to High Performance Code Markus Pueschel (ETH Zuerich, Switzerland) http://www.inf.ethz.ch/~markusp/index.html Specification and verification of meta-programs Martin Berger (University of Sussex, UK) http://www.informatics.sussex.ac.uk/users/mfb21/ ACCEPTED PAPERS Regular research papers: Naoki Kobayashi, Kazutaka Matsuda and Ayumi Shinohara. Functional Programs as Compressed Data Kazutaka Matsuda, Kazuhiro Inaba and Keisuke Nakano. Polynomial-Time Inverse Computation for Accumulative Functions with Multiple Data Traversals Dana N. Xu. Hybrid Contract Checking via Symbolic Simplification Susumu Katayama. An Analytical Inductive Functional Programming System that Avoids Unintended Programs Roberto Giacobazzi, Neil Jones and Isabella Mastroeni. Obfuscation by Partial Evaluation of Distorted Interpreters Michael Gorbovitski, Yanhong A. Liu, Scott Stoller and Tom Rothamel. Composing Transformations for Instrumentation and Optimization Elvira Albert, Jesus Correas Fernandez, German Puebla and Guillermo Roman-Diez. Incremental Resource Usage Analysis Takumi Goto and Isao Sasano. An approach to completing variable names for implicitly typed functional languages Martin Hirzel and Bugra Gedik. Streams that Compose using Macros that Oblige Vlad Ureche, Tiark Rompf, Arvind Sujeeth, Hassan Chafi and Martin Odersky. StagedSAC: A Case Study in Performance-Oriented DSL Development Markus Degen, Peter Thiemann and Stefan Wehr. The Interaction of Contracts and Laziness Surinder Kumar Jain, Chenyi Zhang and Bernhard Scholz. Translating Flowcharts to Non-Deterministic Languages Francisco Javier Lopez-Fraguas, Enrique Martin-Martin and Juan Rodriguez-Hortala. Well-typed Narrowing with Extra Variables in Functional-Logic Programming Geoff Hamilton and Neil Jones. Superlinear Speedup by Distillation: A Semantic Basis Short papers: Jacques Carette and Aaron Stump. Towards Typing for Small-Step Direct Reflection Janis Voigtlaender. Ideas for Connecting Inductive Program Synthesis and Bidirectionalization Tool demonstration papers: Edvard K. Karlsen, Einar W. Hoest and Bjarte M. Oestvold. Finding and fixing Java naming bugs with the Lancelot Eclipse plugin Adriaan Moors, Tiark Rompf, Philipp Haller and Martin Odersky. Scala-Virtualized Elvira Albert, Puri Arenas, Samir Genaim, Miguel Gomez-Zamalloa and German Puebla. COSTABS: A Cost and Termination Analyzer for ABS Simon Thompson | Professor of Logic and Computation School of Computing | University of Kent | Canterbury, CT2 7NF, UK s.j.thompson(a)kent.ac.uk | M +44 7986 085754 | W www.cs.kent.ac.uk/~sjt

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Why does GHC not warn about unnamed uninitialized fields?
by Eelis van der Weegen 23 Nov '11

23 Nov '11

Today I noticed that GHC is more concerned (when using -Wall) about uninitialized fields when those fields have names: data A = A {a::Integer} data B = B Integer x :: A x = A{} -- Gives a nice warning: "Fields of `A' not initialised: a" y :: B y = B{} -- No warning! Is this on purpose? If so, what is the rationale? The context in which I encountered this boils down to the following: {-# LANGUAGE RecordWildCards #-} data C = C {c::Integer} f :: C -> C f C{..} = C{..} g :: C -> Integer g (C i) = i main :: IO () main = print (g (f (C 3))) This code worked fine (and printed "3"), until I made C's Integer nameless. This made it crash with following runtime error instead: T: T.hs:6:11-15: Missing field in record construction The crash and error are perfectly understandable, but it would have been more helpful if GHC had warned about this at compile-time! The reason it didn't, though, is because of its aforementioned cavalier attitude towards uninitialized fields that don't have names... :-) (I'm using GHC 7.0.4.) Cheers, Eelis

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PEPM 2012: Call for participation
by oleg＠okmij.org 23 Nov '11

23 Nov '11

ACM SIGPLAN 2012 Workshop on Partial Evaluation and Program Manipulation http://www.program-transformation.org/PEPM12 January 23-24, 2012. Philadelphia, PA, USA (co-located with POPL'12) Call For Participation Online registration is open at https://regmaster3.com/2012conf/POPL12/register.php Early registration deadline is December 24, 2011 The PEPM Symposium/Workshop series brings together researchers and practitioners working in the broad area of program transformation, which spans from refactoring, partial evaluation, supercompilation, fusion and other metaprogramming to model-driven development, program analyses including termination, inductive programming, program generation and applications of machine learning and probabilistic search. PEPM focuses on techniques, supporting theory, tools, and applications of the analysis and manipulation of programs. In addition to the presentations of regular research papers, the PEPM program includes tool demonstrations and `short paper' presentations of exciting if not fully polished research. PEPM has established a Best Paper award. The winner will be announced at the workshop. INVITED TALKS Compiling Math to High Performance Code Markus Pueschel (ETH Zuerich, Switzerland) http://www.inf.ethz.ch/~markusp/index.html Specification and verification of meta-programs Martin Berger (University of Sussex, UK) http://www.informatics.sussex.ac.uk/users/mfb21/ ACCEPTED PAPERS Regular research papers: Naoki Kobayashi, Kazutaka Matsuda and Ayumi Shinohara. Functional Programs as Compressed Data Kazutaka Matsuda, Kazuhiro Inaba and Keisuke Nakano. Polynomial-Time Inverse Computation for Accumulative Functions with Multiple Data Traversals Dana N. Xu. Hybrid Contract Checking via Symbolic Simplification Susumu Katayama. An Analytical Inductive Functional Programming System that Avoids Unintended Programs Roberto Giacobazzi, Neil Jones and Isabella Mastroeni. Obfuscation by Partial Evaluation of Distorted Interpreters Michael Gorbovitski, Yanhong A. Liu, Scott Stoller and Tom Rothamel. Composing Transformations for Instrumentation and Optimization Elvira Albert, Jesus Correas Fernandez, German Puebla and Guillermo Roman-Diez. Incremental Resource Usage Analysis Takumi Goto and Isao Sasano. An approach to completing variable names for implicitly typed functional languages Martin Hirzel and Bugra Gedik. Streams that Compose using Macros that Oblige Vlad Ureche, Tiark Rompf, Arvind Sujeeth, Hassan Chafi and Martin Odersky. StagedSAC: A Case Study in Performance-Oriented DSL Development Markus Degen, Peter Thiemann and Stefan Wehr. The Interaction of Contracts and Laziness Surinder Kumar Jain, Chenyi Zhang and Bernhard Scholz. Translating Flowcharts to Non-Deterministic Languages Francisco Javier Lopez-Fraguas, Enrique Martin-Martin and Juan Rodriguez-Hortala. Well-typed Narrowing with Extra Variables in Functional-Logic Programming Geoff Hamilton and Neil Jones. Superlinear Speedup by Distillation: A Semantic Basis Short papers: Jacques Carette and Aaron Stump. Towards Typing for Small-Step Direct Reflection Janis Voigtlaender. Ideas for Connecting Inductive Program Synthesis and Bidirectionalization Tool demonstration papers: Edvard K. Karlsen, Einar W. Hoest and Bjarte M. Oestvold. Finding and fixing Java naming bugs with the Lancelot Eclipse plugin Adriaan Moors, Tiark Rompf, Philipp Haller and Martin Odersky. Scala-Virtualized Elvira Albert, Puri Arenas, Samir Genaim, Miguel Gomez-Zamalloa and German Puebla. COSTABS: A Cost and Termination Analyzer for ABS

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Decision procedure for foldr/foldl/foldl'?
by David Fox 22 Nov '11

22 Nov '11

Does anyone have a quick way to decide which of the fold functions to use in a given situation? There are times when I would like to find out which to use in the quickest way possible, rather than reading a long explanation of why each one behaves the way it does.

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Is SmallCheck maintained?
by Roman Cheplyaka 22 Nov '11

22 Nov '11

Hi Cafe, Does anyone currently work on Test.SmallCheck? I see the following problems: 1. SC doesn't have a repository, issue tracker etc. 2. It is not integrated with popular test frameworks 3. API should be better documented I'm willing to work on the above problems, but wanted to check first if someone's already working on them or at least has a repository. I already wrote to Colin Runciman but got no response. -- Roman I. Cheplyaka :: http://ro-che.info/

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FLOPS 2012: 2nd call for papers
by Tom Schrijvers 22 Nov '11

22 Nov '11

Second Call For Papers ===================== *Eleventh International Symposium on Functional and Logic Programming (FLOPS 2012)* May 23-25, 2012 Kobe, Japan [http://www.org.kobe-u.ac.jp/flops2012/] _Submission deadline : December 9, 2011_ FLOPS is a forum for research on all issues concerning declarative programming, including functional programming and logic programming, and aims to promote cross-fertilization and integration between the two paradigms. Previous FLOPS meetings were held in Fuji Susono (1995), Shonan Village (1996), Kyoto (1998), Tsukuba (1999), Tokyo (2001), Aizu (2002), Nara (2004), Fuji Susono (2006), Ise (2008), and Sendai (2010). Topics ====== FLOPS solicits original papers in all areas of functional and logic programming, including (but not limited to): - Declarative Pearls: new and excellent declarative programs with illustrative applications. - Language issues: language design and constructs, programming methodology, integration of paradigms, interfacing with other languages, type systems, constraints, concurrency and distributed computing. - Foundations: logic and semantics, rewrite systems and narrowing, type theory, proof systems. - Implementation issues: compilation techniques, memory management, program analysis and transformation, partial evaluation, parallelism. - Applications: case studies, real-world applications, graphical user interfaces, Internet applications, XML, databases, formal methods and model checking. The proceedings will be published as an LNCS volume. The proceedings of the previous meeting (FLOPS 2010) were published as LNCS 6009. PC co-Chairs ============ - Tom Schrijvers (Ghent University, Belgium) - Peter Thiemann (University of Freiburg, Germany) PC Members ========== - Salvador Abreu (University of Evora, Portugal) - Thorsten Altenkirch (University of Nottingham, UK) - Sebastian Brand (NICTA, Australia) - Giuseppe Castagna (CNRS Univ Paris 7, France) - Sebastian Fischer (Germany) - Marco Gavanelli (University of Ferrara, Italy) - Joxan Jaffar (National University of Singapore, Singapore) - Barry Jay (University of Sydney, Australia) - Andy King (University of Kent, UK) - Claude Kirchner (INRIA, France) - Neelakantan R. Krishnaswami (Microsoft Cambridge, UK) - Yulya Lierler (University of Kentucky, USA) - Keiko Nakata (Tallinn University of Technology, Estonia) - Peter Schneider-Kamp (University of Southern Denmark, Denmark) - Olin Shivers (Northeastern University, USA) - Paul Tarau (University of Northern Texas, USA) - Kazunori Ueda (Waseda University, Japan) - Meng Wang (Chalmers Technical University, Sweden) General Chair and Local co-Chairs ================================= - Naoyuki Tamura (Kobe University, Japan) - Mutsunori Banbara (Kobe University, Japan) - Katsutoshi Hirayama (Kobe University, Japan) Submission ========== Submissions must be unpublished and not submitted for publication elsewhere. Work that already appeared in unpublished or informally published workshops proceedings may be submitted. Submissions should fall into one of the following categories: - Regular research papers: they should describe new results and will be judged on originality, correctness, and significance. - System descriptions: they should contain a link to a working system and will be judged on originality, usefulness, and design. Submissions must be written in English and can be up to 15 pages long, though pearls are typically considerably shorter. Authors are required to use LaTeX2e and the Springer llncs class file, available at [http://www.springer.de/comp/lncs/authors.html] Regular research papers should be supported by proofs and/or experimental results. In case of lack of space, this supporting information should be made accessible otherwise (e.g., a link to a web page, or an appendix). Papers should be submitted electronically at [https://www.easychair.org/conferences/?conf=flops2012] Important Dates =============== - Submission deadline : December 9, 2011 - Author notification : February 3, 2012 - Camera-ready copy : March 2, 2012 Place and Related Events ======================== Takikawa Memorial Hall, Kobe University, 1-1 Rokkodai, Nada, Kobe 657-8501 Japan. The 23rd International Conference on Rewriting Techniques and Applications (RTA 2012) and satellite workshops including WFLP 2012 will be held in the week after FLOPS at Nagoya, Japan. Some Previous FLOPS =================== - FLOPS 2010, Sendai: [http://www.kb.ecei.tohoku.ac.jp/flops2010/] - FLOPS 2008, Ise: [http://www.math.nagoya-u.ac.jp/~garrigue/FLOPS2008/] - FLOPS 2006, Fuji Susono: [http://hagi.is.s.u-tokyo.ac.jp/FLOPS2006/] Sponsors ======== - Japan Society for Software Science and Technology (JSSST) SIGPPL In Cooperation with =================== - ACM SIGPLAN - Asian Association for Foundation of Software (AAFS) - Association for Logic Programming (ALP)

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FLOPS 2012: 2nd call for papers
by Tom Schrijvers 22 Nov '11

22 Nov '11

-- prof. dr. ir. Tom Schrijvers Programming Languages Group Department of Applied Mathematics and Computer Science University of Ghent Krijgslaan 281 S9 9000 Gent Belgium Phone: +32 9 264 4805 http://users.ugent.be/~tschrijv/

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Interpreter with Cont
by oleg＠okmij.org 22 Nov '11

22 Nov '11

I would recommend Ralf Hinze's ICFP00 Pearl Deriving Backtracking Monad Transformers http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.34.4164 He starts with a monad transformer expressed as a free term algebra, and shows step-by-step how to transform it to a more efficient context-passing style. He deals with exceptions and backtracking rather than IO; the ideas are quite similar though.

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FW: [Haskell] Job Opportunity at Parallel Scientific
by Simon Peyton-Jones 22 Nov '11

22 Nov '11

I'm taking the liberty of forwarding this super-relevant advert to Haskell Cafe in case any readers read the Cafe but not the main Haskell mailing list. Simon From: haskell-bounces(a)haskell.org [mailto:haskell-bounces@haskell.org] On Behalf Of Peter Braam Sent: 21 November 2011 22:23 To: haskell Subject: [Haskell] Job Opportunity at Parallel Scientific Parallel Haskell Programmers Parallel Scientific, LLC is a Boulder, CO based early stage, but funded startup company working in the area of scalable parallelization for scientific and large data computing. We are implementing radically new software tools for the creation and optimization of parallel programs benefiting applications and leveraging modern systems architecture. We build on our mathematical knowledge, cutting edge programming languages and our understanding of systems software and hardware. We are currently working with the Haskell development team and major HPC laboratories world wide on libraries and compiler extensions for parallel programming. Parallel Scientific was founded by Dr Peter Braam in 2010. Peter formerly taught mathematics and computer science at Oxford and Carnegie Mellon. Then he contributed file systems to Linux and invented Lustre (which provides storage to 9 of the top 10 systems in the world). He ran several successful startups, and Parallel Scientific is run by an very experienced management team and board. Successful candidates can in some cases work remotely and will work in a modern virtual environment. We provide training in advanced processes for software design and implementation and domain specific knowledge. Required skills: * Very strong background in computer science or mathematics * Experience with Haskell * Knowledge of systems programming and operating systems functionality * Knowledge of system architectures, such as high performance networking, memory architectures, multi and manycore CPUs and GPGPUs * Experience with performance tuning of parallel or concurrent algorithms * Experience designing and implementing concurrent or parallel programs Experience in one or more of the following areas is desirable: * Experience with Haskell compiler technology * In depth knowledge of core Haskell libraries for parallel programming (NDP, REPA etc) * Experience in the area of middleware algorithms for data flow programming, graphs, cloud based data analytics, or sparse matrices * Domain specific knowledge in scientific programming areas related to irregular and sparse problems, e.g. data analytics using graph analysis, genomics, tightly connected numerical analysis * Experience with performance tuning for parallel applications on multi core systems (e.g. with the Intel toolkit), for GPGPU's using Cuda/OpenCL or with MPI/OpenMP on clusters of SMPs To apply, please send a resume to jobs(a)parsci.com<mailto:jobs@parsci.com>.

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