Re: [Haskell-cafe] Proposed change to mime-mail
On Wed, Nov 23, 2011 at 9:39 PM, Erik Hesselink hessel...@gmail.com wrote: Hi all, I've found and solved a problem with mime-mail, and Michael Snoyman asked me to send a request for feedback to -cafe, so here goes. In short, the issue is with address headers containing 'special' (non-ascii) characters. In mime-mail, these are automatically encoded according to RFC 2047. However, the email address part of an address header is not allowed to be encoded. My patch adds 'from', 'to', 'cc' and 'bcc' fields to the Mail data type, and creates correct headers from these fields. This does make the Mail type a bit larger, so I've also added a smart constructor with initializes these fields with empty lists (only 'from' is required). For more details, see my initial bug report [1] and my patches in the pull request [2]. If you have any comments on this change, please let me know. Regards, Erik [1] https://github.com/snoyberg/mime-mail/issues/5 [2] https://github.com/snoyberg/mime-mail/pull/6 ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe Since there were no objections, I've merged the patches and released mime-mail 0.4. Thanks Erik! Michael ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Haskell Platform 64 bit
Hi, On 26.11.2011, at 01:29, Philippe Sismondi wrote: I just tried to install the Haskell Platform 64-bit on OS X Snow Leopard 10.6.8. The install fails with an error. This is all I see in /var/log/install.log: 11-11-25 6:22:01 PM Installer[53992]The Installer encountered an error that caused the installation to fail. Contact the software manufacturer for assistance. Is it known to be broken? I find something in haskell-cafe archives from last spring about a such a problem, but I don't know where to look for anything more recent. I may be blind, but I cannot see anything in the tickets under known problems. just for your information. Currently I am using Lion, and the Haskell Platform 64-bit installer worked fine for me. I am pretty sure it worked on Snow Leopard for me as well. But I can't tell anymore, since I don't have any Snow Leopard machines around. Cheers, Jean ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] PADL 2012 Call for Participation
Call for Participation == 14th International Symposium on Practical Aspects of Declarative Languages (PADL 2012) http://research.microsoft.com/~crusso/padl12 Philadelphia, Pennsylvania, USA, January 23-24, 2012 Co-located with ACM POPL'12 You are cordially invited to PADL'12. PADL is a forum for researchers and practitioners to present original work emphasizing novel applications and implementation techniques for all forms of declarative concepts, including functional, logic and constraints. PADL'12 is sponsored by Association for Logic Programming with cooperation of ACM SIGPLAN and support by Microsoft Research. Registration To register for PADL'12, please follow the instructions at: https://regmaster3.com/2012conf/POPL12/register.php The early registration deadline is December 24, 2011. The registration fee will cover a copy of the symposium proceedings, refreshments, and an informal dinner. Hotel Information = PADL will be co-located with POPL at the Sheraton Society Hill Hotel in Philadelphia. Please visit POPL's web site to make reservations at the special conference rate. Program === The symposium will include invited talks by Boon Thau Loo and Don Stewart, and 19 technical papers selected from 41 submissions. The preliminary program is as follows: Invited Talk (9:00-10:00) * Boon Thau Loo Recent Advances in Declarative Networking Break (10:00-10:30) Session 1: Applications (10:30-12:00) * Mayer Goldberg and Guy Wiener A Declarative Approach for Software Modeling * Sergio Antoy and Michael Hanus Contracts and Specifications for Functional Logic Programming * Pedro M. Martins, Julie A. McCann and Susan Eisenbach The Environment as an Argument Lunch (not provided) (12:00-13:30) Session 2: Logic Programming (13:30-15:30) * Yuliya Lierler, Shaden Smith, Mirek Truszczynski and Alex Westlund Weighted-Sequence Problem: ASP vs CASP and Declarative vs Problem-Oriented Solving * Marcello Balduccini and Yuliya Lierler Practical and Methodological Aspects of the Use of Cutting-Edge ASP Tools * Christian Theil Have and Henning Christiansen Efficient tabling of structured data using indexing and program transformation * Dario Campagna, Beata Sarna-Starosta and Tom Schrijvers Optimizing Inequality Joins in Datalog with Approximated Constraint Propagation Break (15:30-16:00) Session 3: Parallelism and Concurrency (16:00-17:30) * Elvira Albert, Puri Arenas and Miguel Gomez-Zamalloa Symbolic Execution of Concurrent Objects in CLP * Pablo Chico De Guzmán, Amadeo Casas, Manuel Carro and Manuel Hermenegildo A Segment-Swapping Approach for Executing Trapped Computations * Michael Lesniak Palovca: Describing and Executing Graph Algorithms in Haskell Informal PADL Dinner (Place: TBA) Tuesday, January 24, 2012 Breakfast (8:00-9:00) Invited Talk (9:00-10:00) * Don Stewart Make Things Now! Pragmatic Functional Programming in Haskell Break (10:00-10:30) Session 4: Domain Specific Languages I (10:30-12:00) * Kenny Zhu, Kathleen Fisher and David Walker LearnPADS++: Incremental Inference of Ad Hoc Data Formats * Jeroen Bransen, Arie Middelkoop, Atze Dijkstra and S. Doaitse Swierstra The Kennedy-Warren algorithm revisited: ordering Attribute Grammars * Nicholas Coleman Distributed Policy Specification and Interpretation with Classified Advertisements Lunch (not provided) (12:00-13:30) Session 5: Domain Specific Languages II (13:30-15:30) * Andy Gill and Bowe Neuenschwander Handshaking in Kansas Lava using Patch Logic * Daniel Winograd-Cort, Hai Liu and Paul Hudak Virtualizing Real-World Objects in FRP * Edwin Brady and Kevin Hammond Resource-safe Systems Programming with Embedded Domain Specific Languages * David Broman and Henrik Nilsson Node-Based Connection Semantics for Equation-Based Object-Oriented Modeling Languages Break (15:30-16:00) Session 6: Numerics (16:00-17:00) * Paul Tarau A Declarative Specification of Tree-based Symbolic Arithmetic Computations * Vincent St-Amour, Sam Tobin-Hochstadt, Matthew Flatt and Matthias Felleisen Typing the Numeric Tower ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Drawing charts over a lot of data
On 22/11/2011, at 10:55 AM, Bryan O'Sullivan wrote: Be aware that Chart is pretty slow on large data sets. I've noticed this too. I believe the issue is with the cairo bindings - hopefully a new version of gtk2hs will fix this: http://www.mail-archive.com/haskell-cafe@haskell.org/msg94451.html Tim ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Overloaded Strings as default
Hi Cafe, I only feel curious about what would be the consequences of becoming the Overloaded Strings feature (currently, an extension) to be default in Haskell. This is not a proposal. I just want to know what pros and cons there are. Thanks! ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Overloaded Strings as default
On 29 November 2011 07:28, Daniel Díaz Casanueva dhelta.d...@gmail.com wrote: Hi Cafe, I only feel curious about what would be the consequences of becoming the Overloaded Strings feature (currently, an extension) to be default in Haskell. This is not a proposal. I just want to know what pros and cons there are. One cons would be that you may need some more explicit type signatures being used: I have the situation in my graphviz library where both Text and String have instances of some classes (e.g. Labellable, which has a method toLabel :: (Labellable a) = a - Label) which result in explicit String values in the source code result in the compiler not knowing which instance to use (e.g. toLabel hi). -- Ivan Lazar Miljenovic ivan.miljeno...@gmail.com IvanMiljenovic.wordpress.com ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] (no subject)
Hello, I get this error when I try to derive an instance of the Show typeclass: Abc.hs:21:60:Couldn't match expected type `Vector' with actual type `[Point]'In the first argument of `show'', namely `xs'In the second argument of `(++)', namely `show' xs'In the second argument of `(++)', namely `, ++ show' xs'Failed, modules loaded: none. Here's the faulty code: newtype Point = Point Intinstance Show Point where show (Point a) = [chr $ a + 48] data Vector = Vector [Point]instance Show Vector where show (Vector ys) = let show' (Vector [z]) = show z show' (Vector (x:xs)) = show x ++ , ++ show' xs show' (Vector []) = [] in ( ++ show' ys ++ ) What I'm trying to do, is to print out a vector like Vector [Point 1, Point 2, Point 3] as (1, 2, 3).My question is: what should I change in order to make it work? Best regards, William ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] (no subject)
On Mon, Nov 28, 2011 at 4:12 PM, Willem Obbens dub...@hotmail.com wrote: Hello, I get this error when I try to derive an instance of the Show typeclass: Abc.hs:21:60: Couldn't match expected type `Vector' with actual type `[Point]' In the first argument of `show'', namely `xs' In the second argument of `(++)', namely `show' xs' In the second argument of `(++)', namely `, ++ show' xs' Failed, modules loaded: none. Here's the faulty code: newtype Point = Point Int instance Show Point where show (Point a) = [chr $ a + 48] data Vector = Vector [Point] instance Show Vector where show (Vector ys) = let show' (Vector [z]) = show z show' (Vector (x:xs)) = show x ++ , ++ show' xs show' (Vector []) = [] in ( ++ show' ys ++ ) Here you're treating the value 'ys' as if its type was 'Vector', but its type is '[Point]'. Does that help? Antoine ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] (no subject)
On Mon, Nov 28, 2011 at 04:20:54PM -0600, Antoine Latter wrote: On Mon, Nov 28, 2011 at 4:12 PM, Willem Obbens dub...@hotmail.com wrote: Hello, I get this error when I try to derive an instance of the Show typeclass: Abc.hs:21:60: Couldn't match expected type `Vector' with actual type `[Point]' In the first argument of `show'', namely `xs' In the second argument of `(++)', namely `show' xs' In the second argument of `(++)', namely `, ++ show' xs' Failed, modules loaded: none. Here's the faulty code: newtype Point = Point Int instance Show Point where show (Point a) = [chr $ a + 48] data Vector = Vector [Point] instance Show Vector where show (Vector ys) = let show' (Vector [z]) = show z show' (Vector (x:xs)) = show x ++ , ++ show' xs show' (Vector []) = [] in ( ++ show' ys ++ ) You've made show' :: Vector - String, but I'm guessing you actually want to make it show' :: [Point] - String; i.e. get rid of the Vector constructors in the show' patterns. -Brent ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] (no subject)
Yes, thank you. Here's my simple fix: newtype Point = Point Int instance Show Point where show (Point a) = [chr $ a + 48] data Vector = Vector [Point] instance Show Vector where show (Vector ys) = let show' [z] = show z show' (x:xs) = show x ++ , ++ show' xs show' [] = [] in ( ++ show' ys ++ ) And I added this function: createPoint :: Int - PointcreatePoint x = Point x When I loaded the file containing all this into ghci and executed 'Vector $ map createPoint [1..5]' the result was '(1, 2, 3, 4, 5)' (without the quotes).This was actually more or less a test question as I'm new to haskell-cafe, but I hope people who will read this message will learn from my mistake. Thank you. From: aslat...@gmail.com Date: Mon, 28 Nov 2011 16:20:54 -0600 Subject: Re: [Haskell-cafe] (no subject) To: dub...@hotmail.com CC: haskell-cafe@haskell.org On Mon, Nov 28, 2011 at 4:12 PM, Willem Obbens dub...@hotmail.com wrote: Hello, I get this error when I try to derive an instance of the Show typeclass: Abc.hs:21:60: Couldn't match expected type `Vector' with actual type `[Point]' In the first argument of `show'', namely `xs' In the second argument of `(++)', namely `show' xs' In the second argument of `(++)', namely `, ++ show' xs' Failed, modules loaded: none. Here's the faulty code: newtype Point = Point Int instance Show Point where show (Point a) = [chr $ a + 48] data Vector = Vector [Point] instance Show Vector where show (Vector ys) = let show' (Vector [z]) = show z show' (Vector (x:xs)) = show x ++ , ++ show' xs show' (Vector []) = [] in ( ++ show' ys ++ ) Here you're treating the value 'ys' as if its type was 'Vector', but its type is '[Point]'. Does that help? Antoine ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Haskell Platform 64 bit
Please try the following: raptor:~ root# rm -rf /Library/Haskell/ raptor:~ root# cd ~dpp/Library/ raptor:Library root# rm -rf Haskell/ raptor:Library root# cd .. raptor:dpp root# rm -rf .cabal/ raptor:dpp root# I think the issue is that the installer was trying to install on top of an existing installation and that was causing issues. On Fri, Nov 25, 2011 at 4:29 PM, Philippe Sismondi psismo...@arqux.comwrote: I just tried to install the Haskell Platform 64-bit on OS X Snow Leopard 10.6.8. The install fails with an error. This is all I see in /var/log/install.log: 11-11-25 6:22:01 PM Installer[53992]The Installer encountered an error that caused the installation to fail. Contact the software manufacturer for assistance. Is it known to be broken? I find something in haskell-cafe archives from last spring about a such a problem, but I don't know where to look for anything more recent. I may be blind, but I cannot see anything in the tickets under known problems. I have been successfully running the 32-bit version for quite a while, but have begun to run into problems with linking haskell stuff against various 64-bit macports libraries. - Phil - ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe -- 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 ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Built-in LLVM exception handling
Purely out of curiosity, would it be more efficient for GHC to use the new built-in exception handling instructions in LLVM? http://blog.llvm.org/2011/11/llvm-30-exception-handling-redesign.html Cheers, Greg___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] containers-deepseq?
Hi all, Since the release of deepseq 1.2, we've had a bit of a problem: when using the newest versions of packages on Hackage, there is no NFData instance available for the containers types. When GHC 7.4 comes out with its newer version of containers, this will be addressed, but we'll still have problems for users of older GHC releases. I'd like to suggest a solution: a new package called containers-deepseq. Using conditional compilation, it will provide an orphans NFData instance for all containers types when deepseq = 1.2 and containers 0.5. Packages (e.g., aeson) would then depend on containers-deepseq and simply import the module whenever they rely on the NFData instances. When GHC 7.4 comes out, the package will essentially be a no-op. Does this make sense? Michael ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] containers-deepseq?
On Tue, Nov 29, 2011 at 7:43 AM, Michael Snoyman mich...@snoyman.com wrote: Hi all, Since the release of deepseq 1.2, we've had a bit of a problem: when using the newest versions of packages on Hackage, there is no NFData instance available for the containers types. When GHC 7.4 comes out with its newer version of containers, this will be addressed, but we'll still have problems for users of older GHC releases. I'd like to suggest a solution: a new package called containers-deepseq. Using conditional compilation, it will provide an orphans NFData instance for all containers types when deepseq = 1.2 and containers 0.5. Packages (e.g., aeson) would then depend on containers-deepseq and simply import the module whenever they rely on the NFData instances. When GHC 7.4 comes out, the package will essentially be a no-op. Does this make sense? Michael Sorry, that should be containers 0.4.2. Michael ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] (no subject)
On Mon, Nov 28, 2011 at 23:55, Willem O dub...@hotmail.com wrote: And I added this function: createPoint :: Int - Point createPoint x = Point x When I loaded the file containing all this into ghci and executed 'Vector $ map createPoint [1..5]' the result was '(1, 2, 3, 4, 5)' (without the quotes). Note that you do not need this function. You can just use the 'Point' constructor: map Point [1..5] Erik ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
