- Haskell-Cafe - Haskell.org

Visi 0.1 is available for OS X
by David Pollak 18 Apr '12

18 Apr '12

Folks, Visi 0.1 is available as an executable for OS X 10.7 ( http://tunaforcats.com/visi_0_1.tar.bz ) The blog post announcement is available at http://blog.goodstuff.im/visi-01-for-os-x/ Visi is written mostly in Haskell (which is totally awesome, btw). I'll be hacking on Visi this weekend at BayHac '12 ( http://www.haskell.org/haskellwiki/BayHac2012) Thanks, David -- Visi.Pro, Cloud Computing for the Rest of Us http://visi.pro Lift, the simply functional web framework http://liftweb.net Follow me: http://twitter.com/dpp Blog: http://goodstuff.im

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Re: [Haskell-cafe] [Haskell] ANN: cabal-install-0.14.0
by Felipe Almeida Lessa 18 Apr '12

18 Apr '12

On Tue, Apr 17, 2012 at 1:59 PM, Andres Löh <andres.loeh(a)googlemail.com> wrote: > * Completely new modular dependency solver (default in most cases) Great! =D -- Felipe.

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ghc/profiling and very big "entries"
by Emmanuel CHANTREAU 18 Apr '12

18 Apr '12

Hello I got this line in the profile output: COST CENTRE MODULE no. entries %time %alloc %time %alloc ticks bytes addDeduction L42s.Maths.Prover.Base 22730 2362045 1.1 4.6 52.3 52.6 81 614808848 And it seems that "addDeduction" has been called 2 362 045 times ? But from other (personal) log files this function should be called less than 10 000 times. I wonder if the laziness of haskell can grow the "entries" field which is defined by: "The number of times this particular point in the call tree was entered.", but what "enter" means for ghc is a question for me. Thank you for answering -- Emmanuel Chantréau http://www.maretmanu.org/emmanuel/

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ANNOUNCE: haskell-src-exts-1.13.2
by Niklas Broberg 18 Apr '12

18 Apr '12

Fellow Haskelleers, I'm pleased to announce the release of haskell-src-exts-1.13.2! * On hackage: http://hackage.haskell.org/package/haskell-src-exts * Via cabal: cabal install haskell-src-exts * Darcs repo: http://code.haskell.org/haskell-src-exts This release contains only a few small tweaks and bug-fixes. Changelog: 1.13.1 --> 1.13.2 =============== * Fix the bug with the precedence of unary prefix minus. Previously it was resolved as binding more tightly than any infix operator, now it is correctly treated as having the same fixity as binary infix minus. 1.13.0 --> 1.13.1 =============== * Allow an optional semi before the closing tag of an element. This achieves a similar effect for XmlSyntax in do blocks as DoAndIfThenElse does for the if construct. No more need to indent the closing tag one step further than the opening tag. * Add a dummy 'noLoc :: SrcLoc' to L.H.E.SrcLoc, to use when generating code. It could definitely be done more elegantly, but not without inducing another major version bump, so later. * Fix a regression from 1.11.x where the parser would crash upon encountering non-simple class/data declaration heads, e.g. 'data A [a]'. Now fails with a parse error as intended. Cheers, /Niklas

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ANNOUNCE: pipes-core 0.1.0
by Paolo Capriotti 17 Apr '12

17 Apr '12

I'm pleased to announce the release of version 0.1.0 of pipes-core, a library for efficient, safe and compositional IO, similar in scope to iteratee and conduits. http://hackage.haskell.org/package/pipes-core This release fixes a mistake in the previous version which violated the category laws in certain cases. I have now written a fairly explicit proof of the category laws for the current implementation, which I'll try to keep updated as the library evolves: https://github.com/pcapriotti/pipes-core/wiki/Category-laws-for-pipes --- # CHANGELOG for pipes-core: ## Version 0.1.0 - Significant simplification of the internals. - Removed `ensure` primitive. # CHANGELOG for pipes-extra: ## Version 0.1.0 - Improved naming in Control.Pipe.Coroutine. - Replaced ChunkPipe with PutbackPipe. --- BR, Paolo Capriotti

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Osx, brew install of 64 bit ghc
by G 17 Apr '12

17 Apr '12

Got a new ghc via brew 7.0.4 and then recompiled / installed haskell-platform via brew Not getting issue trying to compile using ideah in intellij such as Bad interface file: /usr/local/Cellar/ghc/64-apple-darwin/lib/ghc-7.0.4/base-4.3.1.0/Prelude.hi magic number mismatch: old/corrupt interface file? (wanted 129742, got 33214052) Anyone point me in the right direction as to the issue ? Have tried trashing the project etc with no luck. Thanks

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CFT -- Haskell Implementors' Workshop 2012
by Johan Tibell 17 Apr '12

17 Apr '12

Call for Talks ACM SIGPLAN Haskell Implementors' Workshop http://haskell.org/haskellwiki/HaskellImplementorsWorkshop/2012 Copenhagen, Denmark, September 14th, 2012 The workshop will be held in conjunction with ICFP 2012 http://www.icfpconference.org/icfp2012/ Important dates Proposal Deadline: 10th July 2012 Notification: 27th July 2012 Workshop: 14th September 2012 The Haskell Implementors' Workshop is to be held alongside ICFP 2012 this year in Copenhagen, Denmark. There will be no proceedings; it is an informal gathering of people involved in the design and development of Haskell implementations, tools, libraries, and supporting infrastructure. This relatively new workshop reflects the growth of the user community: there is a clear need for a well-supported tool chain for the development, distribution, deployment, and configuration of Haskell software. The aim is for this workshop to give the people involved with building the infrastructure behind this ecosystem an opportunity to bat around ideas, share experiences, and ask for feedback from fellow experts. We intend the workshop to have an informal and interactive feel, with a flexible timetable and plenty of room for ad-hoc discussion, demos, and impromptu short talks. Scope and target audience ------------------------- It is important to distinguish the Haskell Implementors' Workshop from the Haskell Symposium which is also co-located with ICFP 2012. The Haskell Symposium is for the publication of Haskell-related research. In contrast, the Haskell Implementors' Workshop will have no proceedings -- although we will aim to make talk videos, slides and presented data available with the consent of the speakers. In the Haskell Implementors' Workshop, we hope to study the underlying technology. We want to bring together anyone interested in the nitty-gritty details behind turning plain-text source code into a deployed product. Having said that, members of the wider Haskell community are more than welcome to attend the workshop -- we need your feedback to keep the Haskell ecosystem thriving. The scope covers any of the following topics. There may be some topics that people feel we've missed, so by all means submit a proposal even if it doesn't fit exactly into one of these buckets: * Compilation techniques * Language features and extensions * Type system implementation * Concurrency and parallelism: language design and implementation * Performance, optimisation and benchmarking * Virtual machines and run-time systems * Libraries and tools for development or deployment Talks ----- At this stage we would like to invite proposals from potential speakers for a relatively short talk. We are aiming for 20 minute talks with 10 minutes for questions and changeovers. We want to hear from people writing compilers, tools, or libraries, people with cool ideas for directions in which we should take the platform, proposals for new features to be implemented, and half-baked crazy ideas. Please submit a talk title and abstract of no more than 200 words to: johan.tibell(a)gmail.com We will also have a lightning talks session which will be organised on the day. These talks will be 2-10 minutes, depending on available time. Suggested topics for lightning talks are to present a single idea, a work-in-progress project, a problem to intrigue and perplex Haskell implementors, or simply to ask for feedback and collaborators. Organisers ---------- * Lennart Augustsson (Standard Chartered Bank) * Manuel M T Chakravarty (University of New South Wales) * Gregory Collins - co-chair (Google) * Simon Marlow (Microsoft Research) * David Terei (Stanford University) * Johan Tibell - co-chair (Google)

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process-conduit appears to hang on windows
by grant 16 Apr '12

16 Apr '12

Hi, I am trying to use process-conduit on windows, but it appears to hang when using the conduitCmd. Is there a reason why this doesn't work? Thanks for any help, Grant {-# LANGUAGE QuasiQuotes #-} import System.Process.QQ import Data.Conduit import qualified Data.Conduit.Binary as CB import qualified Data.Conduit.List as CL import Data.Conduit.Process import qualified Data.ByteString as B import System.IO main :: IO () main = runResourceT $ [scmd|dir *.txt|] $$ [ccmd|find /i "help"|] =$ CB.sinkHandle stderr main1::IO() main1 = runResourceT $ sourceCmd "dir" $= conduitCmd "find /i \"help\"" $$ CB.sinkHandle stdout

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Connection to database
by yrazes 16 Apr '12

16 Apr '12

Hi guys, I was trying to get a connection MySql Haskell and I followed this steps: 1. install cabal-install install libghc-haskelldb-hdbc-dev (headers del haskell y hdbc) install libmysqlclient-dev (headers del mysqlclient) 2. git clone git://github.com/bos/hdbc-mysql.git 3. julita@yulys:~/hdbc-mysql$ ls ChangeLog Database README.markdown Test.hs COPYING HDBC-mysql.cabal Setup.lhs testsrc julita@yulys:~/hdbc-mysql$ runhaskell Test.hs but I got this error message: Database/HDBC/MySQL.hs:65:8: Could not find module `Database.HDBC.MySQL.RTS': Use -v to see a list of the files searched for. * I tried to do something about the Setup.lhs, but I could not do anything at all. If somebody can help me, I will appreciate it. Best regards, Julita

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CFP SCAM 2012 - submissions due May 4 (abstracts: April 29)
by Sonia Haiduc 16 Apr '12

16 Apr '12

********************************************************************** * 12th IEEE International Working Conference on Source * * Code Analysis and Manipulation * * SCAM 2012 * * http://scam2012.cs.usask.ca/ * * * * September 23 - 24, 2012 * * Riva Del Garda, Trento, Italy * ********************************************************************** * *** CALL FOR PAPERS *** * ********************************************************************** OVERVIEW/SCOPE ************** The aim of SCAM is to bring together researchers and practitioners working on theory, techniques and applications, which concern analysis and/or manipulation of the source code of computer systems. While much attention in the wider software engineering community is properly directed towards other aspects of systems development and evolution, such as specification, design and requirements engineering, it is the source code that contains the only precise description of the behavior of the system. The analysis and manipulation of source code thus remains a pressing concern. COVERED TOPICS AND PAPER FORMATS ******************************** We welcome submission of *full papers* that describe original and significant work in the field of source code analysis and manipulation. SCAM explicitly solicits results from any theoretical or technological domain that can be applied to the following or similar topics: - program transformation - abstract interpretation - program slicing - source level software metrics - decompilation - source level testing and verification - source level optimization - program comprehension SCAM also welcomes *short tool papers* that introduce tools for source code analysis and manipulation. Tool papers should describe a concrete source code analysis or manipulation tool that is available for download and general use and can be run and demonstrated at the conference. Submitted papers should not be longer than 10 pages (6 pages for tool papers). All papers submitted should follow IEEE Computer Society Press Proceedings Author Guidelines. The papers should be submitted electronically in PDF form via the conference web site.Submitted papers must not have been previously published or concurrently submitted for consideration elsewhere. In addition to the main and tool tracks, SCAM 2012 solicits 2-page *Frontiers position papers* describing a significantly new idea in the theory, technology, application or engineering of source code analysis and manipulation systems. Frontiers authors will join in an open panel discussion of the frontiers of the area at the conference. IMPORTANT DATES *************** Abstract submission (full and frontiers papers): April 29, 2012 Papers submission (full and frontiers papers): May 04, 2012 Tool papers submission: May 31, 2012 Notification full and frontier papers: June 16, 2012 Notification tool papers: June 21, 2012 Camera ready submission: July 06, 2012 Working Conference: September 23 - 24, 2012 PROCEEDINGS *********** All accepted papers will appear in the proceedings which will be published by the IEEE Computer Society Press. Best papers from SCAM 2012 will be considered for revision, extension, and publication in a special issue of the Journal of Software: Evolution and Process. ORGANIZING COMMITTEE ******************** *General Chair* James R. Cordy, Queen's University, Canada *Program Co-Chairs* Mariano Ceccato, Fondazione Bruno Kessler, Italy Zheng Li, Beijing University of Chemical Technology, China *Tool Chair* Chanchal K. Roy, University of Saskatchewan, Canada *Local Arangements Chair* Alessandro Marchetto, Fondazione Bruno Kessler, Italy *Finance Chair* Dave Binkley, Loyola University Maryland, USA *Publications Chair* Dawn Lawrie, Loyola University Maryland, USA *Publicity Chair* Sonia Haiduc, Wayne State University, Detroit, USA *Web chair* Minhaz Fahim Zibran, University of Saskatchewan, Canada

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