[Haskell-cafe] Happstack basic question
Hello haskellers, I want to host a simple happstack application behind a reverse proxy. So ideally would be to bind it to localhost only. According to http://hackage.haskell.org/packages/archive/happstack-server/0.4.1/doc/html/Happstack-Server-HTTP-Types.html#t%3AConf Conf datatyle has only Port field. Does it mean, there is currently no way to prevent binding happstack to all available interfaces? Regards, Dmitry ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Re: [Haskell] ANNOUNCE: Bravo-0.1.0
Hi Matthias, Bravo is inspired by the PHP template engine Smarty and the Haskell Smarty is also about caching. Can you say whether your library support kind of caching as well? Marc Weber ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Cabal and LLVM bindings
Hi! I'm trying to get cabal build my toy compiler, which is based on llvm bindings on hackage. Everything is fine with ghc --make, but with cabal install I get: Loading package llvm-0.7.1.1 ... command line: can't load .so/.DLL for: LLVMSystem (dlopen(libLLVMSystem.dylib, 9): image not found) cabal: Error: some packages failed to install: QV-0.1 failed during the building phase. The exception was: ExitFailure 1 This is done on os x 10.5.8, if that has any relevance. Anyone got any hints on how to proceed with this? Ville Tirronen ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] ANN: powerpc-0.0.1
2010/3/10 Tom Hawkins tomahawk...@gmail.com: On Wed, Mar 10, 2010 at 8:07 AM, Warren Henning warren.henn...@gmail.com wrote: Wow. Quite ambitious. Was this inspired by work at your current employer like with Atom and some of the other stuff you've released? Yes, we had an immediate need to debug some machine code. I looked around, but all the emulators I found (PSIM, et al.) were too complicated. I'm also intrigued by the emphasis on software verification at the object code level for aerospace (DO-178). I figure better tools in this area may open the door to using advanced design methods like Atom for avionics. Of course it's unlikely this project will reach that level of maturity, but you never know. We wrote the debugger and simulator for AVR line of microcontroller cores. We used a DSEL to describe inner workings of commands and now try to apply it to ARM ISA. The Haskell code is heavy on the use of type-level computations and, especially, assiciated types. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Happstack basic question
Hi Dmitry, On Thu, Mar 11, 2010 at 11:38:44AM +0300, Dmitry V'yal wrote: Hello haskellers, I want to host a simple happstack application behind a reverse proxy. So ideally would be to bind it to localhost only. According to http://hackage.haskell.org/packages/archive/happstack-server/0.4.1/doc/html/Happstack-Server-HTTP-Types.html#t%3AConf Conf datatyle has only Port field. Does it mean, there is currently no way to prevent binding happstack to all available interfaces? I think you are looking for simpleHTTPWithSocket [1]. You can use whatever socket you like. Regards, Dmitry Cheers, Martin [1] http://happstack.com/docs/0.4/happstack-server/Happstack-Server-SimpleHTTP.html#v%3AsimpleHTTPWithSocket ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Re: Anyone up for Google SoC 2010?
Yakov Zaytsev wrote: I've got N900 recently and saw that according to this page http://hackage.haskell.org/trac/ghc/wiki/Platforms it's not possible to run GHC and GHCi easily on ARM. This sucks. According to this page, shared libraries are not supported on *any* platform except MacOS. Surely that's no longer true? ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Re: Anyone up for Google SoC 2010?
On Thu, Mar 11, 2010 at 2:13 PM, Andrew Coppin andrewcop...@btinternet.comwrote: According to this page, shared libraries are not supported on *any* platform except MacOS. Surely that's no longer true? They are supported on Linux too now [1]. I don't know the status regarding Windows though. [1] http://haskell.org/ghc/docs/latest/html/users_guide/using-shared-libs.html -- Alp Mestanogullari http://alpmestan.wordpress.com/ http://alp.developpez.com/ ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Re: Anyone up for Google SoC 2010?
Alp Mestanogullari wrote: On Thu, Mar 11, 2010 at 2:13 PM, Andrew Coppin andrewcop...@btinternet.com mailto:andrewcop...@btinternet.com wrote: According to this page, shared libraries are not supported on *any* platform except MacOS. Surely that's no longer true? They are supported on Linux too now [1]. I don't know the status regarding Windows though. Yeah, I thought the IHG recently spent a bunch of money on getting it working on Linux. I gather Windows is a lowER priority (although it IS on the to-do list). It seems there's a bunch of information about GHC on the GHC developer's website, but it's often not especially up-to-date. (I guess the GHC devs have code to write, after all...) ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] definition of sum
TeXitoi wrote: why is foldl used by Data.List for sum? Daniel Fischer wrote: Because Haskell is a non-strict language, and foldl' is strict -- someone might write a (legitimate) Num instance for a datatype such that foldl (+) 0 xs returns a good value, but foldl' (+) 0 xs gives ***Exception: Prelude.undefined for some lists xs. It is possible to define such a Num instance, but it is extremely rare for anything like that to come up in practice. However, with optimisations turned on... GHC knows that sum is actually strict GHC does that when optimizations are turned on, but that behavior is not required by the Haskell standard. So there is no guarantee that any given compiler will produce usable output if you use foldl instead of foldl' for sum. In GHCi sum is broken, because optimizations are not in effect there. You have to define your own version of sum using foldl' for every GHCi session (or put it in your .ghci file). So it's a trade-off between a slight convenience in a bizarre corner case and general usability. I agree with Don that this is a bug in the Haskell 98 standard. Regards, Yitz ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Happstack basic question
You misunderstand his question. He's trying to setup happstack behind a reverse proxy running on the same system, so he needs to be able to bind it only to the loopback interface (127.0.0.1), as opposed to all the interfaces on the system (thereby making it inaccessible from the network unless accessed through the proxy). I don't know enough about happstack to answer his question, but I can see from the documentation you provided that there doesn't seem to be any way to specify address to bind to as Dmitry stated in his original e-mail. -R. Kyle Murphy -- Curiosity was framed, Ignorance killed the cat. On Thu, Mar 11, 2010 at 07:39, Martin Kiefel m...@nopw.de wrote: Hi Dmitry, On Thu, Mar 11, 2010 at 11:38:44AM +0300, Dmitry V'yal wrote: Hello haskellers, I want to host a simple happstack application behind a reverse proxy. So ideally would be to bind it to localhost only. According to http://hackage.haskell.org/packages/archive/happstack-server/0.4.1/doc/html/Happstack-Server-HTTP-Types.html#t%3AConf Conf datatyle has only Port field. Does it mean, there is currently no way to prevent binding happstack to all available interfaces? I think you are looking for simpleHTTPWithSocket [1]. You can use whatever socket you like. Regards, Dmitry Cheers, Martin [1] http://happstack.com/docs/0.4/happstack-server/Happstack-Server-SimpleHTTP.html#v%3AsimpleHTTPWithSocket ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Happstack basic question
On Thu, Mar 11, 2010 at 09:24:05AM -0500, Kyle Murphy wrote: You misunderstand his question. He's trying to setup happstack behind a reverse proxy running on the same system, so he needs to be able to bind it only to the loopback interface (127.0.0.1), as opposed to all the interfaces on the system (thereby making it inaccessible from the network unless accessed through the proxy). I don't know enough about happstack to answer his question, but I can see from the documentation you provided that there doesn't seem to be any way to specify address to bind to as Dmitry stated in his original e-mail. But I'm doing exactly that. Here is some of the code: main = do ... s - socket AF_INET Stream defaultProtocol setSocketOption s ReuseAddr 1 h - getHostByName localhost let p = toEnum $ port $ httpConf appConf bindSocket s (SockAddrInet p (hostAddress h)) listen s 10 -- start the state system control - startSystemState' (store appConf) stateProxy -- start the http server httpTid - forkIO $ simpleHTTPWithSocket s (httpConf appConf) ... And then my happstack server is just listening on 127.0.0.1. To access it, I'm using Apache Proxy. - Martin -R. Kyle Murphy -- Curiosity was framed, Ignorance killed the cat. On Thu, Mar 11, 2010 at 07:39, Martin Kiefel m...@nopw.de wrote: Hi Dmitry, On Thu, Mar 11, 2010 at 11:38:44AM +0300, Dmitry V'yal wrote: Hello haskellers, I want to host a simple happstack application behind a reverse proxy. So ideally would be to bind it to localhost only. According to http://hackage.haskell.org/packages/archive/happstack-server/0.4.1/doc/html/Happstack-Server-HTTP-Types.html#t%3AConf Conf datatyle has only Port field. Does it mean, there is currently no way to prevent binding happstack to all available interfaces? I think you are looking for simpleHTTPWithSocket [1]. You can use whatever socket you like. Regards, Dmitry Cheers, Martin [1] http://happstack.com/docs/0.4/happstack-server/Happstack-Server-SimpleHTTP.html#v%3AsimpleHTTPWithSocket ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Problem installing wxHaskell on Haskell Platform on OSX.
On Mar 10, 2010, at 6:33 PM, Daniel Fischer wrote: cabal install wx-0.12.1.2 wxcore-0.12.1.2 wxdirect-0.12.1.1 has good chances to work on 6.10.* I have managed to install and compile this version of wxHaskell. Now, I have a problem using it. The instructions on the use of wxHaskell on OSX say to follow this recipe: cd samples/wx ghc -package wx -o helloworld HelloWorld.hs /usr/local/wxhaskell/bin/macosx-app -v helloworld open helloworld.app The installation did not create the directory /usr/local/wxhaskell and I can't find the macosx-app anywhere else. Help, please. Thanks.___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Space leak
Hi Arnoldo
This doesn't address the space leak, but your parseChromosome function
looks very inefficient - isInfixOf is repeatedly checking the prefix
chromosome for C1 to CY. If you have a lot of CY's in a file then it
will do a lot of work parsing them.
The cleanest way of handling this would be to use a parser combinator
library with keywords for chromosome and mitochondrion - however
that might add a performance penalty itself.
Here is a version that should be fairly efficient although a little
ugly due to how it has to match literal chars in prefix of the string:
Add a import for Data.Char to the import list:
import Data.Char
Add Enum to the deriving clause of the Chromosome data type:
| C19
| CX
| CY
| CMT
deriving (Show,Enum)
Replace parseChromosome with the one below.
Note that the derived Enum functions for Chromosome are indexed from
0.. whereas when you read one from the file it is indexed from 1.. so
you have to sub1 before using toEnum:
sub1 :: Int - Int
sub1 x = x-1
parseChromosome :: [Char] - Chromosome
parseChromosome ('c':'h':'r':'o':'m':'o':'s':'o':'m':'e':' ':xs) = chro xs
where
chro ('X' :_) = CX
chro ('Y' :_) = CY
chro ( x : ',' :_)| isDigit x = toEnum (sub1 $ digitToInt x)
chro ('1' : x : ',' :_ ) | isDigit x = toEnum (sub1 $ (10+) $
digitToInt x)
chro ('1' : x :_ ) | isDigit x = toEnum (sub1 $ (10+) $
digitToInt x)
chro _ = error BAD header
parseChromosome ('m':'i':'t':'o':'c':'h':'o':'n':'d':'r':'i':'o':'n':_) = CMT
parseChromosome _ = error BAD header
Best wishes
Stephen
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Re: [Haskell-cafe] Cabal and LLVM bindings
Do you happen to use template haskell? It looks like the interpreter is trying to load llvm, which is currently not supported. That doesn't explain why it works with ghc --make though. Do you do anything special in your .cabal file? On 11 March 2010 12:30, Ville Tirronen alea...@gmail.com wrote: Hi! I'm trying to get cabal build my toy compiler, which is based on llvm bindings on hackage. Everything is fine with ghc --make, but with cabal install I get: Loading package llvm-0.7.1.1 ... command line: can't load .so/.DLL for: LLVMSystem (dlopen(libLLVMSystem.dylib, 9): image not found) cabal: Error: some packages failed to install: QV-0.1 failed during the building phase. The exception was: ExitFailure 1 This is done on os x 10.5.8, if that has any relevance. Anyone got any hints on how to proceed with this? Ville Tirronen ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe -- Push the envelope. Watch it bend. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Happstack basic question
Ah, I see, I was looking at the example code in the Happstack documentation you linked. Looking at the documentation of Network.Socket I can see where it provides an option to bind on a particular address. The example given in the Happstack docs uses bindPort to get the socket which confused me as didn't realize you could initialize a socket using the Network.Socket functions and just pass that instead. The example in your latest mail is much clearer. -R. Kyle Murphy -- Curiosity was framed, Ignorance killed the cat. On Thu, Mar 11, 2010 at 09:35, Martin Kiefel m...@nopw.de wrote: On Thu, Mar 11, 2010 at 09:24:05AM -0500, Kyle Murphy wrote: You misunderstand his question. He's trying to setup happstack behind a reverse proxy running on the same system, so he needs to be able to bind it only to the loopback interface (127.0.0.1), as opposed to all the interfaces on the system (thereby making it inaccessible from the network unless accessed through the proxy). I don't know enough about happstack to answer his question, but I can see from the documentation you provided that there doesn't seem to be any way to specify address to bind to as Dmitry stated in his original e-mail. But I'm doing exactly that. Here is some of the code: main = do ... s - socket AF_INET Stream defaultProtocol setSocketOption s ReuseAddr 1 h - getHostByName localhost let p = toEnum $ port $ httpConf appConf bindSocket s (SockAddrInet p (hostAddress h)) listen s 10 -- start the state system control - startSystemState' (store appConf) stateProxy -- start the http server httpTid - forkIO $ simpleHTTPWithSocket s (httpConf appConf) ... And then my happstack server is just listening on 127.0.0.1. To access it, I'm using Apache Proxy. - Martin -R. Kyle Murphy -- Curiosity was framed, Ignorance killed the cat. On Thu, Mar 11, 2010 at 07:39, Martin Kiefel m...@nopw.de wrote: Hi Dmitry, On Thu, Mar 11, 2010 at 11:38:44AM +0300, Dmitry V'yal wrote: Hello haskellers, I want to host a simple happstack application behind a reverse proxy. So ideally would be to bind it to localhost only. According to http://hackage.haskell.org/packages/archive/happstack-server/0.4.1/doc/html/Happstack-Server-HTTP-Types.html#t%3AConf Conf datatyle has only Port field. Does it mean, there is currently no way to prevent binding happstack to all available interfaces? I think you are looking for simpleHTTPWithSocket [1]. You can use whatever socket you like. Regards, Dmitry Cheers, Martin [1] http://happstack.com/docs/0.4/happstack-server/Happstack-Server-SimpleHTTP.html#v%3AsimpleHTTPWithSocket ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] definition of sum
Am Donnerstag 11 März 2010 15:23:32 schrieb Yitzchak Gale: TeXitoi wrote: why is foldl used by Data.List for sum? Daniel Fischer wrote: Because Haskell is a non-strict language, and foldl' is strict -- someone might write a (legitimate) Num instance for a datatype such that foldl (+) 0 xs returns a good value, but foldl' (+) 0 xs gives ***Exception: Prelude.undefined for some lists xs. It is possible to define such a Num instance, but it is extremely rare for anything like that to come up in practice. Yes. And I'd expect foldr (+) 0 to be much more useful for lazy Num instances than foldl (+) 0. Nevertheless, one has to take that possibility into account. However, with optimisations turned on... GHC knows that sum is actually strict GHC does that when optimizations are turned on, but that behavior is not required by the Haskell standard. So there is no guarantee that any given compiler will produce usable output if you use foldl instead of foldl' for sum. In GHCi sum is broken, because optimizations are not in effect there. You have to define your own version of sum using foldl' for every GHCi session (or put it in your .ghci file). So it's a trade-off between a slight convenience in a bizarre corner case and general usability. I agree with Don that this is a bug in the Haskell 98 standard. I'm not sure whether it's a wart or a bug, but I agree that it would be better to have the default sum strict (and provide lazysum for the cases where it's useful). Regards, Yitz Cheers, Daniel ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] definition of sum
However, with optimisations turned on... GHC knows that sum is actually strict GHC does that when optimizations are turned on, but that behavior is not required by the Haskell standard. So there is no guarantee that any given compiler will produce usable output if you use foldl instead of foldl' for sum. In GHCi sum is broken, because optimizations are not in effect there. You have to define your own version of sum using foldl' for every GHCi session (or put it in your .ghci file). So it's a trade-off between a slight convenience in a bizarre corner case and general usability. I agree with Don that this is a bug in the Haskell 98 standard. I'm not sure whether it's a wart or a bug, but I agree that it would be better to have the default sum strict (and provide lazysum for the cases where it's useful). That would be really inconsistent with the way the rest of the Haskell language and libraries works. Note that foldl' has a ' to indicate that it's not the same as foldl exactly. I would propose that sum' exist as well as sum, and that sum be lazy. Part of what's interesting about Haskell is the default non-strict evaluation of the language, and even if it's hard for newcomers to get used to it, they're better off having a consistent space to work in rather than all these exceptions to make algorithms like sum work more efficiently when the problem was one of documentation and education about the language. Of course if you want a strict functional language there's plenty of those out there. Dave Regards, Yitz Cheers, Daniel ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] ANN: powerpc-0.0.1
Serguey, I'm working on a similar project. What's the chance you have your source code in the open? /jve On Thu, Mar 11, 2010 at 7:30 AM, Serguey Zefirov sergu...@gmail.com wrote: 2010/3/10 Tom Hawkins tomahawk...@gmail.com: On Wed, Mar 10, 2010 at 8:07 AM, Warren Henning warren.henn...@gmail.com wrote: Wow. Quite ambitious. Was this inspired by work at your current employer like with Atom and some of the other stuff you've released? Yes, we had an immediate need to debug some machine code. I looked around, but all the emulators I found (PSIM, et al.) were too complicated. I'm also intrigued by the emphasis on software verification at the object code level for aerospace (DO-178). I figure better tools in this area may open the door to using advanced design methods like Atom for avionics. Of course it's unlikely this project will reach that level of maturity, but you never know. We wrote the debugger and simulator for AVR line of microcontroller cores. We used a DSEL to describe inner workings of commands and now try to apply it to ARM ISA. The Haskell code is heavy on the use of type-level computations and, especially, assiciated types. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] ANN: powerpc-0.0.1
2010/3/11 John Van Enk vane...@gmail.com: Serguey, I'm working on a similar project. What's the chance you have your source code in the open? /jve I'll ask. But chances are pretty small. I'll think about reimplementing command description from scratch. On Thu, Mar 11, 2010 at 7:30 AM, Serguey Zefirov sergu...@gmail.com wrote: 2010/3/10 Tom Hawkins tomahawk...@gmail.com: On Wed, Mar 10, 2010 at 8:07 AM, Warren Henning warren.henn...@gmail.com wrote: Wow. Quite ambitious. Was this inspired by work at your current employer like with Atom and some of the other stuff you've released? Yes, we had an immediate need to debug some machine code. I looked around, but all the emulators I found (PSIM, et al.) were too complicated. I'm also intrigued by the emphasis on software verification at the object code level for aerospace (DO-178). I figure better tools in this area may open the door to using advanced design methods like Atom for avionics. Of course it's unlikely this project will reach that level of maturity, but you never know. We wrote the debugger and simulator for AVR line of microcontroller cores. We used a DSEL to describe inner workings of commands and now try to apply it to ARM ISA. The Haskell code is heavy on the use of type-level computations and, especially, assiciated types. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] ANN: powerpc-0.0.1
Serguey, The system I'm writing has a type in place for the AVR instruction set. I'm working on writing an assembler/disassembler for it as well. It might make sense, if your employer deems it worthwhile to release the code, to collaborate. /jve On Thu, Mar 11, 2010 at 11:35 AM, Serguey Zefirov sergu...@gmail.comwrote: 2010/3/11 John Van Enk vane...@gmail.com: Serguey, I'm working on a similar project. What's the chance you have your source code in the open? /jve I'll ask. But chances are pretty small. I'll think about reimplementing command description from scratch. On Thu, Mar 11, 2010 at 7:30 AM, Serguey Zefirov sergu...@gmail.com wrote: 2010/3/10 Tom Hawkins tomahawk...@gmail.com: On Wed, Mar 10, 2010 at 8:07 AM, Warren Henning warren.henn...@gmail.com wrote: Wow. Quite ambitious. Was this inspired by work at your current employer like with Atom and some of the other stuff you've released? Yes, we had an immediate need to debug some machine code. I looked around, but all the emulators I found (PSIM, et al.) were too complicated. I'm also intrigued by the emphasis on software verification at the object code level for aerospace (DO-178). I figure better tools in this area may open the door to using advanced design methods like Atom for avionics. Of course it's unlikely this project will reach that level of maturity, but you never know. We wrote the debugger and simulator for AVR line of microcontroller cores. We used a DSEL to describe inner workings of commands and now try to apply it to ARM ISA. The Haskell code is heavy on the use of type-level computations and, especially, assiciated types. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Re: Cabal dependency hell
On Mon, Mar 8, 2010 at 2:31 PM, Maciej Piechotka uzytkown...@gmail.com wrote: On Mon, 2010-03-08 at 15:37 +0100, Marc Weber wrote: We can't expect package maintainers to test everything. So it must be people like you and me who fixes those changes. Well. Except that it require bumping versions. Which according to hackage policy requires to fork a project (which makes it pointless in the first place) This isn't quite that dire -- I've adopted the following practice when I encounter a cabal dependency issue: (a) identify the problem (eg: observing `cabal install foo` fails) (b) get the source via hackage: `cabal unpack foo` (c) fix the unpacked version, and increment the version number by adding a new level of detail (so, 3.1.0 becomes 3.1.0.1). This version number never leaves my system -- it only exists to keep my cabal/ghc-pkg consistent! (d) if possible, verify that the problem still exists in the project's actual source control (e) email the maintainer, and if possible, including a patch to the current head of the revision control system for the project. So far, it's worked pretty well :) Everyone I've sent patches to has been very responsive and helpful, often pushing updated versions to hackage by the end of the day. The way to go is make hackage allow changing constraints on the fly notifying the author that he can update his repository. You can, at times, do this by forcing constraints via cabal command line flags, or by installing packages with a version specification. $ cabal install foo-1.2.3 will install that specific version of foo. --Rogan This will work in most cases. Bumping versions because a dependency has changed is bad as well. This will cause to much overhead (and it dosen't solve the problem because the old package is still wrong). Specifying dependencies must be decoupled from bumping versions. It's because dep specs do depend on the world which can change.. At least that's what I think. Hmm. When I was returning home I thought about some wiki-like system that would allow to say 'Package X is compatible/not compatible with Y'. Possibly something like: - Only the 'sure' deps are installed in default mode - When in 'expert' mode I can install any package which has not been marked as incompatible Then I can say that I tested built and: - It failed to built - It failed the automatic tests (if they exists)/does not work - It success So if there is versions: 0.7 0.8 0.9 1.0 1.0.1 1.1 1.2 1.3 1.4 And: - 0.8 failed to built - =1.0 1.1 was marked by author - 1.1 was marked as success - 1.3 failed to build Then - In default/normal mode it can be used with 1.0, 1.0.1 and 1.1 - In expert mode 0.9 and 1.2 can be installed in addition to above - Any version can be installed in 'I'm feeling lucky' mode when I explicitly say package to ignore some restriction Possibly it is needed to collect user karma (or possibly already account verification is sufficient). If you're interested in Nix and hack-nix I can show you how everything works using an SSH session. Ekhm... SSH? Marc Weber Regards ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] ANN: powerpc-0.0.1
2010/3/11 John Van Enk vane...@gmail.com:
Serguey,
The system I'm writing has a type in place for the AVR instruction set. I'm
working on writing an assembler/disassembler for it as well. It might make
sense, if your employer deems it worthwhile to release the code, to
collaborate.
/jve
Our work is concerned with semantics of operations.
So we build a list of Commands:
data Command cpu = Command {
cmdName :: String -- right now it's just a string, but it could
be a pretty printer
-- with calculations for disasm.
,cmdFormat :: [Match cpu] -- when we decode a command in a simulation,
-- we set some CPU variables.
-- that's what Match encode.
,cmdStatements :: [Stat cpu] -- the semantics of command.
}
And then we use that list to generate code for our simulation package.
Lately we found that we could use those command descriptions for other
purposes, like automatic code generator generators, etc, but we didn't
explored all that yet.
So we don't have a specific type of AVR commands. We have general
description of (almost) arbitrary CPU commands which we successfully
applied to AVR line of microcontroller cores.
Statements contains assignments (Variable cpu size := Expression cpu
size), conditionals and various CPU- and bus-specific function
invocation (like read from memory or write to it).
On Thu, Mar 11, 2010 at 11:35 AM, Serguey Zefirov sergu...@gmail.com
wrote:
2010/3/11 John Van Enk vane...@gmail.com:
Serguey,
I'm working on a similar project. What's the chance you have your source
code in the open?
/jve
I'll ask.
But chances are pretty small.
I'll think about reimplementing command description from scratch.
On Thu, Mar 11, 2010 at 7:30 AM, Serguey Zefirov sergu...@gmail.com
wrote:
2010/3/10 Tom Hawkins tomahawk...@gmail.com:
On Wed, Mar 10, 2010 at 8:07 AM, Warren Henning
warren.henn...@gmail.com wrote:
Wow. Quite ambitious.
Was this inspired by work at your current employer like with Atom
and
some of the other stuff you've released?
Yes, we had an immediate need to debug some machine code. I looked
around, but all the emulators I found (PSIM, et al.) were too
complicated.
I'm also intrigued by the emphasis on software verification at the
object code level for aerospace (DO-178). I figure better tools in
this area may open the door to using advanced design methods like
Atom
for avionics. Of course it's unlikely this project will reach that
level of maturity, but you never know.
We wrote the debugger and simulator for AVR line of microcontroller
cores.
We used a DSEL to describe inner workings of commands and now try to
apply it to ARM ISA.
The Haskell code is heavy on the use of type-level computations and,
especially, assiciated types.
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[Haskell-cafe] ANN: HaskellTorrent v0.1.1
Hello Cafe, I am pleased to announce yet another release of the HaskellTorrent project. In this release, focus has been on improving upon the work laid in v0.0. Highlights include: * Certain data structures have changed from Data.List to Data.IntSet, yielding much improved performance. * Addition of a GetOpt option parser. * Use of test-framework to run unit-tests. * Assertion optimization, cutting down CPU usage by quite a margin. * Change SHA1 checksumming to use Peter Simons hopenssl package. This plugged some serious memory leaks. * Support for listen() on port 1579 so incoming connections get handled correctly. * Support for more graceful stopping. The supervisor tree is now terminated in the opposite order of creation. * When closing down, tell the tracker we are stopping. * Add KeepAlive messages on idle socket connections. * Improve the console interface a bit so it is quasi-usable. * Change the logging framework from my own to hslogger by John Goerzen. It is better than my attempts and it shaves 150 lines of code from the project not having to maintain a logging framework. This also makes the client BEP003 compliant, so we can now claim to be a full BitTorrent client. Looking forward, I'd like to get less CPU usage, and support for more BitTorrent extensions. -- There are still bugs in the code, so watch out for spinning processes. Also, performance is still far from optimal. From a profiler run, we get the following: total time = 64.26 secs (3213 ticks @ 20 ms) total alloc = 6,712,153,496 bytes (excludes profiling overheads) COST CENTREMODULE %time %alloc MAIN MAIN 58.03.7 assertPieceDB Process.PieceMgr 13.4 29.6 logP Process3.76.0 syncP Process2.8 12.1 download Main 2.10.0 updateBS Digest 2.10.0 recvP Process2.04.3 choosePProcess1.97.0 receiverP Process.Peer 1.81.5 peerP Process.Peer 1.20.6 grabBlocks'Process.PieceMgr 1.03.1 senderPProcess.Peer 1.01.4 sendP Process0.93.1 checkPiece FS 0.76.1 msgPeerProcess.ChokeMgr 0.62.4 registerL Process.Timer 0.21.9 getByteString Data.Serialize.Get 0.21.0 newBuffer Data.Serialize.Builder 0.0 10.1 which tells us we are still allocating far too much memory. I wonder what the 58.0% on MAIN means (this is with -prof -auto-all -caf-all). The code is heavily concurrent, using the cml package. My guess is that we have somewhere between 500 and 1000 threads when running. I ponder if that has something to do with it. The price of assertPieceDB can easily be removed by running the assertions at a rarer pace. -- J. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Re: Anyone up for Google SoC 2010?
On 11 March 2010 13:42, Andrew Coppin andrewcop...@btinternet.com wrote: Yeah, I thought the IHG recently spent a bunch of money on getting it working on Linux. I gather Windows is a lowER priority (although it IS on the to-do list). AFAIK shared libraries now work on Windows - Ben Lippmeier (under the auspices of the IHG) recently commited what were apparently the missing pieces there. I haven't actually tried it out though. Cheers, Max ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Re: Anyone up for Google SoC 2010?
Would be great to see GHC on Maemo. I recently bought an N900 and googled around to see if this is possible to write Haskell for the platform. The short answer is 'not easily' There are some old notes on getting previous versions compiling, but nothing up to date I gave up pretty quickly :-( On Wed, 2010-03-10 at 17:43 -0500, Yakov Zaytsev wrote: I've got N900 recently and saw that according to this page http://hackage.haskell.org/trac/ghc/wiki/Platforms it's not possible to run GHC and GHCi easily on ARM. This sucks. I want to propose a project bring GHC back to life on arm-linux. It is supposed that the outcome will be a package for Maemo 5. Actually, I want to apply for this project as a student. I hope to make NCG for ARM working in some sense. Dear list, what do you think about it? -- Yakov ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Re: Anyone up for Google SoC 2010?
On Thu, Mar 11, 2010 at 10:02:42PM +, phil wrote: Would be great to see GHC on Maemo. I recently bought an N900 and googled around to see if this is possible to write Haskell for the platform. Just a note, jhc works just fine for cross-compiling to maemo. It is one of the first cross-platform targets I tested with. John -- John Meacham - ⑆repetae.net⑆john⑈ - http://notanumber.net/ ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Re: ANNOUNCE: Bravo-0.1.0
Thank you, how does it compare to HStringTemplate ? ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Space leak
Am Donnerstag 11 März 2010 00:24:28 schrieb Daniel Fischer:
Hmm, offhand, I don't see why that isn't strict enough.
Turns out, mapM_ was a red herring. The villain was (zip and map).
I must confess, I don't know why it sort-of worked without the mapM_,
though. sort-of, because that also hung on to unnecessarily much memory,
the space leak was just smaller than with the mapM_.
A very small change that eliminates the space leak, is
readFasta :: Int - [Char] - [Window]
readFasta windowSize sequence =
-- get the header
let (header,rest) = span (/= '\n') sequence
chr = parseChromosome header
go i (w:ws) = Window w chr i : go (i+1) ws
go _ [] = []
in go 0 $ slideWindow windowSize $ filter (/= '\n') rest
You can improve performance by eliminating slideWindow and the intermediate
Window list (merging fastaExtractor and readFasta),
{-# LANGUAGE BangPatterns #-}
readFasta2 :: (String - Bool) - Int - String
readFasta2 test windowSize sequence =
let (header,rest) = span (/= '\n') sequence
chr = parseChromosome header
schr = show chr
go !i st@(_:tl)
| test w= w ++ '\t' : schr ++ '\t' : show i ++ '\n' : go
(i+1) tl
| otherwise = go (i+1) tl
where
w = take windowSize st
go _ [] = []
in go 0 (filter (/= '\n')) rest
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Re: [Haskell-cafe] Space leak
Daniel,
Thank you so much for helping me out with this issue!
Thanks to all the other answers from haskel-cafe members too!
As a newbie, I am not able to understand why zip and map would make a
problem...
Is there any link I could read that could help me to understand why in this
case
zip and map created a leak? What are some function compositions that should
be
avoided when doing lazy I/O?
Regards,
Arnoldo
On Thu, Mar 11, 2010 at 11:46 PM, Daniel Fischer
daniel.is.fisc...@web.dewrote:
Am Donnerstag 11 März 2010 00:24:28 schrieb Daniel Fischer:
Hmm, offhand, I don't see why that isn't strict enough.
Turns out, mapM_ was a red herring. The villain was (zip and map).
I must confess, I don't know why it sort-of worked without the mapM_,
though. sort-of, because that also hung on to unnecessarily much memory,
the space leak was just smaller than with the mapM_.
A very small change that eliminates the space leak, is
readFasta :: Int - [Char] - [Window]
readFasta windowSize sequence =
-- get the header
let (header,rest) = span (/= '\n') sequence
chr = parseChromosome header
go i (w:ws) = Window w chr i : go (i+1) ws
go _ [] = []
in go 0 $ slideWindow windowSize $ filter (/= '\n') rest
You can improve performance by eliminating slideWindow and the intermediate
Window list (merging fastaExtractor and readFasta),
{-# LANGUAGE BangPatterns #-}
readFasta2 :: (String - Bool) - Int - String
readFasta2 test windowSize sequence =
let (header,rest) = span (/= '\n') sequence
chr = parseChromosome header
schr = show chr
go !i st@(_:tl)
| test w= w ++ '\t' : schr ++ '\t' : show i ++ '\n' : go
(i+1) tl
| otherwise = go (i+1) tl
where
w = take windowSize st
go _ [] = []
in go 0 (filter (/= '\n')) rest
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[Haskell-cafe] Re: [Haskell] ANNOUNCE: Bravo-0.1.0
Hi Marc, I'm sorry, the current Bravo version does not support caching of evaluated templates. Maybe this will be a feature of later releases. Matthias Am 11.03.2010 10:02 schrieb Marc Weber: Hi Matthias, Bravo is inspired by the PHP template engine Smarty and the Haskell Smarty is also about caching. Can you say whether your library support kind of caching as well? Marc Weber ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Re: ANNOUNCE: Bravo-0.1.0
Am 11.03.2010 23:38 schrieb Simon Michael: Thank you, how does it compare to HStringTemplate ? Hi Simon, I never worked with HStringTemplate, so as far as I can tell after having a glance at the HStringTemplate API and the wiki page, the main difference is that Bravo parses the templates at compile time, while HStringTemplate does at runtime. Besides that, HStringTemplate provides several methods for rendering different data types in different styles. This can also be accomplished in Bravo by writing the appropriate rendering function in your Haskell code and using it in the template. Regards, Matthias ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] ANNOUNCE: Bravo-0.1.0
Matthis, Thank you for releasing this library, it looks very intriguing. I've been building web apps using HStringTemplate up until now, and one thing that always irks me is that- while the rest of my program is checked at compile-time- my template results need to be checked manually at runtime. One of my todo-list items was to write a library that fixed this: it looks like yours does just that. I'll need to look into the library a bit more to get a better idea, but it seems like Bravo could work for my needs. One thing that concerns me is your comment that it allows embedding of Haskell expressions. In general, I try to keep a strict separation between login and presentation: can you explain exactly what type of expressions can be embedded? Also, while looking through the example, it looks like the library is making some automatic translations, like firstName - userFirstName and user - users. I've found these kinds of mappings to be brittle in the past; can you explain how this is done (or if I'm simply missing something obvious)? Finally, I can't seem to get it to compile on 6.12. Any chance of getting a version out that supports it? Thanks, Michael On Wed, Mar 10, 2010 at 8:46 PM, Matthias Reisner matthias.reis...@googlemail.com wrote: Hello, I'm pleased to announce the first release of Bravo, a static text template generation library, on Hackage: http://hackage.haskell.org/package/Bravo. Bravo is a text template library that provides parsing and generation of templates at compile time. Templates can be read from strings or files and for each a new record data type is created, allowing convenient access to all template variables in a type-safe manner. Since all templates are processed at compile time, no extra file access or error handling at runtime is necessary. Bravo is inspired by the PHP template engine Smarty and the Haskell template library chunks. Compared to chunks, Bravo provides additional features like conditional template evaluation, embedding of Haskell expressions and customized data type generation. I'm going to add further information to the HaskellWiki page ( http://www.haskell.org/haskellwiki/Bravo) later. Bravo is still highly experimental and not well-tested, so bug reports and additional feedback are very welcome. I'd also like to hear if you feel the package dependencies are to restrictive. Regards, Matthias Reisner ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] 3rd party widgets with qtHaskell (Marble)
On Wed, 2010-03-10 at 11:22 +0100, Alp Mestanogullari wrote: This something you are afaik able to do. I'm cc'ing David (qthaskell's author). Thanks for the reply. I've worked it out. The below code demonstrates getting and setting a property from a marble widget. I'm a little surprised it worked. If my C++ is right what I've done here is dynamically cast the Marble widget as it's Qt parent. This of course is fine, but given that longitude() is not a virtual function on the parent, I'd to have to cast as the child to access this function - my code shouldn't have scope of Marble specific functions. This doesn't follow C++ (or I need to brush up on my OO programming!). I can live with this, after all I'm not writing a C++ program, but if anyone can explain this I'd be interested to understand why. One other peculiarity I noticed was that the qVariant constructor will only take Double or Integer types if they are nested in a tuple. Again, this is fine, but at odds with the documentation which implies constructors can take: () | p1 | (p1) | (p1,p2,...pn) So I'm over the first hurdle; it is possible, now to think of something interesting to do with it :-) module Main where import Qtc main :: IO () main = do app - qApplication () rok - registerResource marble.rcc loader - qUiLoader () uiFile - qFile :/marble.ui open uiFile fReadOnly ui - load loader uiFile close uiFile () ui_map - findChild ui (QWidget*, marbleWidget) ui_button - findChild ui (QPushButton*, pushButton) sc - qObjectProperty ui_map longitude bt - qObjectProperty ui_button text long - qVariantValue_Double sc print long x - qVariant (-1::Double) blah - qObjectSetProperty ui_map longitude x qshow ui () ok - qApplicationExec () return () ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] ANNOUNCE: Bravo-0.1.0
Hi Michael Am 12.03.2010 01:33 schrieb Michael Snoyman: I'll need to look into the library a bit more to get a better idea, but it seems like Bravo could work for my needs. One thing that concerns me is your comment that it allows embedding of Haskell expressions. In general, I try to keep a strict separation between login and presentation: can you explain exactly what type of expressions can be embedded? This is really one disadvantage of the current Bravo version I'm worrying about too. At the moment you can insert arbitrary Haskell expressions, so no one prevents the template writer from inserting expressions like `unsafePerformIO launchAtomicMissile return '. Some kind of security mechanism will definitely be included in future releases, but I'm not sure in what way at the moment. I thought about passing a list of permitted function names to the template creation function and then failing with an error if any other functions are used. Also, while looking through the example, it looks like the library is making some automatic translations, like firstName - userFirstName and user - users. I've found these kinds of mappings to be brittle in the past; can you explain how this is done (or if I'm simply missing something obvious)? Bravo creates a data type per template, where the default naming scheme for the data type/constructor name is name - TplName. For each template variable a record field is created; for a template temp and a variable var the name will be tempVar. Have a look at the `mkTemplatesWithOptions' and `mkTemplatesFromFileWithOptions' functions, that allow you to customize this naming scheme. Finally, I can't seem to get it to compile on 6.12. Any chance of getting a version out that supports it? The problem seems to be haskell-src-meta, that doesn't like template-haskell-2.4, and on the other side I can't get build template-haskell 2.4 with GHC-6.12. So I will contact Matt Morrow, the maintainer of haskell-src-meta, and see if he can fix it. Regards, Matthias Thanks, Michael On Wed, Mar 10, 2010 at 8:46 PM, Matthias Reisner matthias.reis...@googlemail.com wrote: Hello, I'm pleased to announce the first release of Bravo, a static text template generation library, on Hackage: http://hackage.haskell.org/package/Bravo. Bravo is a text template library that provides parsing and generation of templates at compile time. Templates can be read from strings or files and for each a new record data type is created, allowing convenient access to all template variables in a type-safe manner. Since all templates are processed at compile time, no extra file access or error handling at runtime is necessary. Bravo is inspired by the PHP template engine Smarty and the Haskell template library chunks. Compared to chunks, Bravo provides additional features like conditional template evaluation, embedding of Haskell expressions and customized data type generation. I'm going to add further information to the HaskellWiki page ( http://www.haskell.org/haskellwiki/Bravo) later. Bravo is still highly experimental and not well-tested, so bug reports and additional feedback are very welcome. I'd also like to hear if you feel the package dependencies are to restrictive. Regards, Matthias Reisner ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] If wishes were horses... (was: Re: definition of sum)
David Leimbach wrote: Note that foldl' has a ' to indicate that it's not the same as foldl exactly. I would propose that sum' exist as well as sum, and that sum be lazy. I wish Haskell allowed ! to occur (non-initially) in alphanum_' identifiers as well as in symbolic ones. Then we could be more consistent about having ! mean strictness like it does with ($!), bang patterns, strict fields,... (too bad about (!) and (!!)). The prime has so many other uses, it's a shame it gets used up for strict/lazy variants, as if there were no other variations. -- Live well, ~wren ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] How to do the permutation and combination thing?
Hi, For example, I have this: list1 = [a, b, c] list2 = [d, e, f] list3 = [g, h, i] Now I want: [ [(a, d, g), (b, e, h), (c, f, i)] , ... ] -- a list that contains all the combinations. How to do it pretty? Thanks. -- 竹密岂妨流水过 山高哪阻野云飞 ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] How to do the permutation and combination thing?
This sounds like homework. Think in abstract terms what you want to accomplish. Start with the simplest case first, usually the base case. On Fri, 12 Mar 2010 14:02:02 +0800, you wrote: Hi, For example, I have this: list1 = [a, b, c] list2 = [d, e, f] list3 = [g, h, i] Now I want: [ [(a, d, g), (b, e, h), (c, f, i)] , ... ] -- a list that contains all the combinations. How to do it pretty? Thanks. -- Regards, Casey ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] How to do the permutation and combination thing?
All I could get is to use permutations and concatMap. But it looks really ugly. On Fri, Mar 12, 2010 at 2:09 PM, Casey Hawthorne cas...@istar.ca wrote: This sounds like homework. Think in abstract terms what you want to accomplish. Start with the simplest case first, usually the base case. On Fri, 12 Mar 2010 14:02:02 +0800, you wrote: Hi, For example, I have this: list1 = [a, b, c] list2 = [d, e, f] list3 = [g, h, i] Now I want: [ [(a, d, g), (b, e, h), (c, f, i)] , ... ] -- a list that contains all the combinations. How to do it pretty? Thanks. -- Regards, Casey ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe -- 竹密岂妨流水过 山高哪阻野云飞 ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
