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A video of Frag
by Korcan Hussein 11 Nov '08

11 Nov '08

I don't understand why there is no video of Frag online so I made one here: http://uk.youtube.com/watch?v=0jYdu2u8gAU _________________________________________________________________ BigSnapSearch.com - 24 prizes a day, every day - Search Now! http://clk.atdmt.com/UKM/go/117442309/direct/01/

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Haskell Weekly News: Issue 92 - November 8, 2008
by Brent Yorgey 10 Nov '08

10 Nov '08

--------------------------------------------------------------------------- Haskell Weekly News http://sequence.complete.org/hwn/20081108 Issue 92 - November 08, 2008 --------------------------------------------------------------------------- Welcome to issue 92 of HWN, a newsletter covering developments in the [1]Haskell community. GHC 6.10 is released!! Go forth and drool over its new features. Be sure to have the editline libraries (libedit-dev on Debian/Ubuntu, for example) installed before you try building it. Announcements GHC version 6.10.1. Ian Lynagh [2]announced the release of [3]GHC version 6.10.1! This new major release features a number of significant changes, including wild-card patterns, punning, and field disambiguation in record syntax; generalised quasi-quotes; generalised SQL-like list comprehensions; view patterns; a complete reimplementation of type families; parallel garbage collection; a new extensible exception framework; a more user-friendly API; included Data Parallel Haskell (DPH); and more! See [4]the full release notes for more information. new community.haskell.org features: webspace, mailing lists. Ian Lynagh [5]announced that the community server, http://community.haskell.org/, has two new features for hosted projects: project webspace, and project mailing lists. GHC blog. Simon Marlow [6]has set up a [7]GHC blog. This is for all things related to GHC, particularly people working on GHC to blog about what they're up to. If you want a write-bit, sign up for a [8]wordpress account, let Simon know your account name, and blog away! The GHC blog should be syndicated on [9]Planet Haskell soon. Haddock 2.4.0. David Waern [10]announced a [11]new release of [12]Haddock, the Haskell documentation tool. This is a later version than the one shipped with GHC 6.10.1, which is version 2.3.0. That version will not be released on Hackage since it only builds with GHC 6.10.1 (by accident, actually). Besides adding back support for earlier GHC versions, this release contains some more fixes and support for HTML frames. htags-1.0. David Sankel [13]announced the [14]htags package, a tag file generator to enable extra functionality in editors like vim. It expands upon hasktags by using a full Haskell 98 parser and options for recursion. Haskell Quick Reference (1-page PDF). Malcolm Wallace [15]sent a 1-page Haskell quick reference prepared for a recent Haskell tutorial. Permission is granted for anyone to distribute it more widely as they wish, in the hope that it might be useful. Editable sources can be passed along if anyone would like to extend it. Proposal for associated type synonyms in Template Haskell. Thomas van Noort [16]submitted a proposal for adding associated type synonyms to Template Haskell. Comments are welcomed. announce [("InfixApplicative", 1.0), ("OpenGLCheck", 1.0), ("obj", 0.1)]. Thomas Davie [17]announced the upload of a few packages to Hackage which he has produced while working at Anygma. [18]obj-0.1 is a library for loading and writing obj 3D models; [19]OpenGLCheck-1.0 is a micro-package containing instances of Arbitrary for the data structures provided in Graphics.Rendering.OpenGL; and [20]InfixApplicative-1.0 is a second micro-package containing a pair of functions (<^) and (^>) which can be used to provide an infix version of liftA2 applied to an operator. Graphalyze-0.5 and SourceGraph-0.3. Ivan Lazar Miljenovic [21]announced the latest versions of [22]Graphalyze and [23]SourceGraph, which fix a couple of bugs in the previous versions. zlib and bzlib 0.5 releases. Duncan Coutts [24]announced updates to the [25]zlib and [26]bzlib packages, featuring a slightly nicer extended API. The simple API that most packages use is unchanged. There is also a new parameter to control the size of the first output buffer; this lets applications save memory when they happen to have a good estimate of the output size. Discussion Efficient parallel regular expressions. Martijn van Steenbergen [27]asked about efficiently running multiple regular expressions in parallel, leading to an interesting discussion of regular expressions and various parsing methods and libraries. Problems with strictness analysis?. Patai Gergely started an informative [28]discussion about strictness, laziness, strictness analysis, and compiler optimization. If you don't know a lot about these topics but would like to learn, this thread is a good starting point! Jobs 1-year postdoc position in Chalmers Functional Programming group. John Hughes [29]announced a position for a post-doctoral researcher with the Chalmers Functional Programming Group, with a one-year tax-free stipend funded by Intel. The funded project will develop a Domain Specific Language (DSL) for high level modelling, design and analysis of hardware and microarchitectures. Blog noise [30]Haskell news from the [31]blogosphere. * Edward Kmett: [32]Still Alive. Edward is still alive but sadly lost a few recursion scheme posts. =( * >>> Max Rabkin: [33]Beautiful folding. A very cool post about composable folds! * Eric Kow (kowey): [34]timesheet helper. * Philip Wadler: [35]A bizarre function over streams. * David Sankel: [36]Introducing Reactive: Events. A very readable introduction to the Reactive library. I look forward to reading more! * "FP Lunch": [37]Numbers vs Sets. * Mark Jason Dominus: [38]Addenda to recent articles 200810. * Darcs: [39]darcs weekly news #11. * >>> Ken G.: [40]Haskell?. Ken shares some thoughts on Real World Haskell. * Real-World Haskell: [41]Some early reviews. * David Sankel: [42]freeglut + Windows + HOpenGL + HGLUT. * GHC mutterings: [43]GHC 6.10.1 is out!. * Chung-chieh Shan: [44]Cognitive jobs. * London Haskell Users Group: [45]Duncan Coutts: The Haskell Platform. The abstract for Duncan's talk at the London HUG. * Well-Typed.Com: [46]GHC 6.10.1 released!. * Well-Typed.Com: [47]Haskell Platform talk at the London Haskell Users Group. * Mark Wassell: [48]GIS with Haskell 1. * >>> phoenix: [49]Haskell Tricks: Indexing a List. Getting the index of an element satisfying a predicate by zipping. * JP Moresmau: [50]Haskell for counting votes!. JP illustrates five different voting methods with some Haskell implementations. * Ivan Lazar Miljenovic: [51]Graph Theoretic Analysis of Relationships within Discrete Data. * Braden Shepherdson: [52]Pimp Your XMonad #1: Status bars. The first in a planned series of articles on not-so-well-known ways to extend your xmonad configuration. * >>> Cory: [53]Euler and Haskell. Cory just started learning Haskell (a "fun, slightly ridiculous language") via Project Euler. * >>> Sadek Drobi: [54]Code Safety and Correctness is a matter of Mindset Cultured by the Language. * Well-Typed.Com: [55]zlib and bzlib package updates. * >>> Bryan St. Amour: [56]Haskell Solution To The Farmer Problem. * >>> Nathan Hartman: [57]Haskell, Lambert, and the Clarke Ellipsoid. Nathan has started porting a map projection library to Haskell. * David Sankel: [58]Analysis of lazy-stream programs.. Quotes of the Week * Cory: Any language which makes frequent use of monads, functors and has a wikibook describing its relation to category theory is the result of an evil genius (or several, to be precise). * mmorrow: in langs with dependent types, you can just map numbers directly to types instead of having to ride a unicycle along a tightrope while battling an unruly gang of monkeys with knives. * conal: -fsemantics-shemantics * roconnor: all sorts of wonderful things could be done if we are less anal about bottoms. No pun intended. About the Haskell Weekly News New editions are posted to [59]the Haskell mailing list as well as to [60]the Haskell Sequence and [61]Planet Haskell. [62]RSS is also available, and headlines appear on [63]haskell.org. To help create new editions of this newsletter, please see the information on [64]how to contribute. Send stories to byorgey at cis dot upenn dot edu. The darcs repository is available at darcs get [65]http://code.haskell.org/~byorgey/code/hwn/ . References 1. http://haskell.org/ 2. http://article.gmane.org/gmane.comp.lang.haskell.glasgow.user/15591 3. http://www.haskell.org/ghc/ 4. http://haskell.org/ghc/docs/6.10.1/html/users_guide/release-6-10-1.html 5. http://article.gmane.org/gmane.comp.lang.haskell.general/16600 6. http://article.gmane.org/gmane.comp.lang.haskell.glasgow.user/15603 7. http://ghcmutterings.wordpress.com/ 8. http://wordpress.com/ 9. http://planet.haskell.org/ 10. http://www.haskell.org//pipermail/haskell-cafe/2008-November/050271.html 11. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/haddock-2.4.0 12. http://www.haskell.org/haddock 13. http://article.gmane.org/gmane.comp.lang.haskell.general/16582 14. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/htags 15. http://article.gmane.org/gmane.comp.lang.haskell.cafe/47344 16. http://article.gmane.org/gmane.comp.lang.haskell.cafe/47301 17. http://article.gmane.org/gmane.comp.lang.haskell.cafe/47241 18. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/obj 19. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/OpenGLCheck 20. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/InfixApplicative 21. http://article.gmane.org/gmane.comp.lang.haskell.cafe/47171 22. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/Graphalyze 23. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/SourceGraph 24. http://article.gmane.org/gmane.comp.lang.haskell.cafe/47144 25. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/zlib 26. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/bzlib 27. http://thread.gmane.org/gmane.comp.lang.haskell.cafe/47242 28. http://thread.gmane.org/gmane.comp.lang.haskell.cafe/47183 29. http://article.gmane.org/gmane.comp.lang.haskell.general/16596 30. http://planet.haskell.org/ 31. http://haskell.org/haskellwiki/Blog_articles 32. http://comonad.com/reader/2008/still-alive/ 33. http://squing.blogspot.com/2008/11/beautiful-folding.html 34. http://koweycode.blogspot.com/2008/11/timesheet-wishlist.html 35. http://wadler.blogspot.com/2008/11/bizarre-function-over-streams.html 36. http://netsuperbrain.com/blog/posts/introducing-reactive-events/ 37. http://sneezy.cs.nott.ac.uk/fplunch/weblog/?p=114 38. http://blog.plover.com/addenda/200810.html 39. http://blog.darcs.net/2008/11/darcs-weekly-news-11.html 40. http://monolith149daily.blogspot.com/2008/11/haskell.html 41. http://www.realworldhaskell.org/blog/2008/11/06/some-early-reviews/ 42. http://netsuperbrain.com/blog/posts/freeglut-windows-hopengl-hglut/ 43. http://ghcmutterings.wordpress.com/2008/11/05/ghc-6101-is-out/ 44. http://conway.rutgers.edu/~ccshan/wiki/blog/posts/Cognitive_jobs/ 45. http://www.londonhug.net/2008/11/04/duncan-coutts-the-haskell-platform/ 46. http://blog.well-typed.com/2008/11/ghc-6101-released/ 47. http://blog.well-typed.com/2008/11/haskell-platform-talk-at-the-london-hask… 48. http://pound-stone.blogspot.com/2008/11/gis-with-haskell-1.html 49. http://phoenixblitz.blogspot.com/2008/11/haskell-tricks-indexing-list.html 50. http://jpmoresmau.blogspot.com/2008/11/haskell-for-counting-votes.html 51. http://ivanmiljenovic.wordpress.com/2008/11/03/graph-theoretic-analysis-of-… 52. http://braincrater.wordpress.com/2008/11/02/pimp-your-xmonad-1-status-bars/ 53. http://onag.blogspot.com/2008/11/euler-and-haskell.html 54. http://sadekdrobi.com/2008/11/02/code-safety-and-correctness-is-a-matter-of… 55. http://blog.well-typed.com/2008/11/zlib-and-bzlib-package-updates/ 56. http://bryanstamour.com/?p=49 57. http://parsemymonad.blogspot.com/2008/10/haskell-lambert-and-clarke-ellipso… 58. http://netsuperbrain.com/blog/posts/analysis-of-lazy-stream-programs/ 59. http://www.haskell.org/mailman/listinfo/haskell 60. http://sequence.complete.org/ 61. http://planet.haskell.org/ 62. http://sequence.complete.org/node/feed 63. http://haskell.org/ 64. http://haskell.org/haskellwiki/HWN 65. http://code.haskell.org/~byorgey/code/hwn/

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Haskell source packages in Hackage
by Hugo Pacheco 10 Nov '08

10 Nov '08

Hi guys, I am having an hard time installing the haskell-src and haskell-src-exts packages, since both seem to have problems with happy. I have installed happy 1.18.2 successfully, but it does not seem to be visible (although the happy executable is in my path). I get the errors: $ cabal install haskell-src Resolving dependencies... 'haskell-src-1.0.1.3' is cached. Configuring haskell-src-1.0.1.3... Preprocessing library haskell-src-1.0.1.3... cabal: The program happy is required but it could not be found cabal: Error: some packages failed to install: haskell-src-1.0.1.3 failed during the building phase. The exception was: exit: ExitFailure 1 $ cabal install haskell-src-exts Resolving dependencies... 'haskell-src-exts-0.3.9' is cached. Configuring haskell-src-exts-0.3.9... cabal: happy version >=1.17 is required but it could not be found. cabal: Error: some packages failed to install: haskell-src-exts-0.3.9 failed during the configure step. The exception was: exit: ExitFailure 1 Is this some kind of bug in cabal, or in the packages themselves? Thanks, hugo -- www.di.uminho.pt/~hpacheco

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generalized list comprehensions
by Johannes Waldmann 10 Nov '08

10 Nov '08

Looking at this funny new feature http://haskell.org/ghc/docs/6.10.1/html/users_guide/syntax-extns.html#gener… I have just one question - why doesn't this work with the do-notation? I avoid list comprehensions because I feel that "return" belongs at the end, not in front. If I recall correctly, "putting the SQL-select where it belongs" is a slogan used by Hijlsberg to justify the LINQ syntax for C#, and of course he is right. Now ghc copies LINQ (syntactically), but stops halfway? Just wondering - J.W.

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Are arbitrary rank types and existentials equivalent?
by Loup Vaillant 10 Nov '08

10 Nov '08

Maybe one subsumes the other? What I want to know is if there is an easy way to emulate one with the other, and how much convenience is lost in doing so. For instance, is it possible to implement stream fusion with rank2 types, or the ST monad with existantials? Is there any paper discussing this kind of things? Thanks, Loup

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ANN (sorta): OpenGL with extra type safety
by Neal Alexander 10 Nov '08

10 Nov '08

I recently modified the hOpenGL (and GLFW) source tree to force extra type checking on its various IO actions using the -XGeneralizedNewtypeDeriving extension (see http://hackage.haskell.org/trac/ghc/ticket/736) The main motivation was for writing concurrent OpenGL applications. Here its important to know what functions contain OpenGL commands so they can be directed to the proper threads (ones with active rendering contexts). Plus it aids in partitioning work that can be offloaded or done asynchronously. The second motivation was to enforce static type checking on commands that can only be executed in certain OpenGL contexts (sending vertex data for example). As it is now, there are 3 new monads (their names will probably change): OpenGLM: the basic opengl command PrimitiveM: commands that can only be issued between begin/end() class MonadGL: commands that can be issued in any GL context Now for the big question: Does anyone care? If so, should i make it a new hackageDB package, or try to merge it into the official GL package. Ideally, it'd be nice to get some more input on the API changes, since they're more or less a rough draft as is. Also, the GLU modules were all placed in the OpenGLM monad, which is probably wrong, assuming some commands can be called between begin/end. I'll post the code later if anyone is interested. ---------------- class MonadIO m => MonadGL m instance MonadGL OpenGLM instance MonadGL PrimitiveM newtype OpenGLM a = OpenGLM (IO a) deriving (Functor, Monad, MonadIO) newtype PrimitiveM a = PrimitiveM (IO a) deriving (Functor, Monad, MonadIO)

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Announce: FieldTrip library (functional 3D) and mailing list
by Conal Elliott 10 Nov '08

10 Nov '08

FieldTrip [1] is a library for functional 3D graphics. It is intended for building static, animated, and interactive 3D geometry, efficient enough for real-time synthesis and display. Since FieldTrip is functional, one describes what models are, not how to render them (being rather than doing). Surfaces are described as functions from 2D space to 3D space. As such, they are intrinsically curved rather than faceted. Surface rendering tessellates adaptively, caching tessellations in an efficient, infinite data structure (from the MemoTrie library) for reuse. Surface normals are computed automatically and exactly, using the derivative tools in the vector-space library. For animation or interaction, FieldTrip can be used with the Reactive [2] library for functional reactive programming (and possibly other animation frameworks). By design, FieldTrip is completely orthogonal to any formulation or implementation of FRP. The reactive-fieldtrip [3] library links Reactive and FieldTrip. FieldTrip now has a mailing list [4] and a feature/bug tracker [5]. [1] http://haskell.org/haskellwiki/FieldTrip [2] http://haskell.org/haskellwiki/reactive [3] http://haskell.org/haskellwiki/reactive-fieldtrip [4] http://www.haskell.org/mailman/listinfo/FieldTrip [5] http://trac.haskell.org/FieldTrip

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FFI documentation?
by Nun Aurbiz 10 Nov '08

10 Nov '08

Where do I find the documentation for the FFI for GHC? I've read the FFI report, the GHC user guide and scoured haskell.org but they all gloss over what commands you actually need to give GHC and how to give them. "foreign import blah blah" just gives me undefined references.

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Re: [Haskell-cafe] A video of Frag
by Hugo Pacheco 10 Nov '08

10 Nov '08

Yes, I installed it via cabal-install.I am using GHC 6.10.1 now, but it had > the same results in 6.6 (if I remember well) before. It may be a Mac issue. > > On Mon, Nov 10, 2008 at 1:39 PM, Korcan Hussein <korcan_h(a)hotmail.com>wrote: > >> Sorry I have no idea, which version of GHC are you using? did you try >> using cabal-install? ( >> http://hackage.haskell.org/trac/hackage/wiki/CabalInstall) >> >> ------------------------------ >> Date: Mon, 10 Nov 2008 10:46:45 +0000 >> >> From: hpacheco(a)gmail.com >> To: korcan_h(a)hotmail.com >> Subject: Re: [Haskell-cafe] A video of Frag >> >> Oh, sorry I haven't noticed.Trying to compile in my OS X machine, all >> compiles ok via cabal, but then I get >> >> $ ./frag ../share/frag-1.1.2/leveleg >> Bus error >> >> I remember compiling frag 1/2 years ago and getting the same result. >> It is not windows, but do you have any hint? >> >> On Mon, Nov 10, 2008 at 10:12 AM, Korcan Hussein <korcan_h(a)hotmail.com>wrote: >> >> Actually such a package already exists, it's quite a simple procedure as >> long as you have the right tools and and setup but for windows platform >> this information is a bit scattered/dispersed and there is no central >> information about getting such a thing up and running from complete scratch. >> This is what i'm referring to in my comment. >> >> ------------------------------ >> Date: Mon, 10 Nov 2008 09:15:14 +0000 >> From: hpacheco(a)gmail.com >> To: korcan_h(a)hotmail.com >> Subject: Re: [Haskell-cafe] A video of Frag >> CC: haskell-cafe(a)haskell.org >> >> >> I read on your youtube post that you are planning to write a >> build-it-yourself tutorial. Perhaps this effort could be targeted at >> creating a cabal package in Hackage (I do not know the implications of that, >> just speaking out loud). >> >> Cheers, >> hugo >> >> 2008/11/10 Korcan Hussein <korcan_h(a)hotmail.com> >> >> I don't understand why there is no video of Frag online so I made one >> here: http://uk.youtube.com/watch?v=0jYdu2u8gAU >> >> ------------------------------ >> Click here for FREE customisable desktop wallpapers. Get them Now!<http://wallpapers.msn.com/?ocid=%5BB001MSN42A0716B%5D> >> >> _______________________________________________ >> Haskell-Cafe mailing list >> Haskell-Cafe(a)haskell.org >> http://www.haskell.org/mailman/listinfo/haskell-cafe >> >> >> >> >> -- >> www.di.uminho.pt/~hpacheco <http://www.di.uminho.pt/%7Ehpacheco> >> >> ------------------------------ >> Click here for FREE customisable desktop wallpapers. Get them Now!<http://wallpapers.msn.com/?ocid=%5BB001MSN42A0716B%5D> >> >> >> >> >> -- >> www.di.uminho.pt/~hpacheco <http://www.di.uminho.pt/%7Ehpacheco> >> >> ------------------------------ >> Get the best wallpapers on the Web - FREE. Click here!<http://wallpapers.msn.com/?ocid=[B001MSN42A0716B]> >> > > > > -- > www.di.uminho.pt/~hpacheco >

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announcing darcs 2.1.1rc2
by Eric Kow 10 Nov '08

10 Nov '08

Hi everybody, The release candidate for darcs 2.1.1 is now available at http://darcs.net/darcs-2.1.1rc2.tar.gz This release is very much intended to be darcs 2.1.0 plus GHC 6.10.1 support. We have also thrown in some simplifications to the regression testing suite and a Windows bugfix (which we pulled in because of a dependency and retained because it was a small and useful). Please give this a try, especially those of you on GHC 6.10 or Windows, and let us know how things work out. Because we have only selected a very small subset of changes to include (using darcs's cherry-picking abilities, of course!), I am confident that we can get by on a reduced release cycle. If all goes well, the official release date for darcs 2.1.1 will be 2008-11-17. Thanks! Eric darcs (2.1.1rc2) * Portability: Removed accidental QuickCheck 2.1 configure check. Note that it may be required in a future version of darcs. -- Eric Kow <kowey(a)darcs.net> Mon, 10 Nov 2008 11:17:00 GMT darcs (2.1.1rc1) * Portability: GHC 6.10.1 support (Petr Ročkai, Eric Kow) * Bug Fix: Fix file handle leak and check for exceptions on process running on Windows (issue784, Salvatore Insalaco) * Quality Assurance: Consolidated regression test suites using shell scripts only (Eric Kow, Tommy Petterson, Matthias Kilian) -- Eric Kow <kowey(a)darcs.net> Mon, 10 Nov 2008 09:49:00 GMT -- Eric Kow <http://www.nltg.brighton.ac.uk/home/Eric.Kow> PGP Key ID: 08AC04F9

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