Re: [Haskell-cafe] Number 1, at least for now
On Wed, 2006-02-01 at 19:14 -0800, John Meacham wrote: though, I think this is a great oprotunity to improve ghc's optimizer. Huh, that would be the best thing with the whole shootout endeavour.. Sincerely, Gour signature.asc Description: This is a digitally signed message part ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
RE: [Haskell-cafe] Number 1, at least for now
| though, I think this is a great oprotunity to improve ghc's optimizer. | | Huh, that would be the best thing with the whole shootout endeavour.. Yes indeed. One thing that would be really helpful, as a first step, would be to identify a bunch of concrete examples that GHC should have optimised, or perhaps could have optimised, and attach them to the GHC wiki somewhere. One place would be here http://haskell.org/haskellwiki/Performance or perhaps somewhere on the developers wiki, or as a task. http://hackage.haskell.org/trac/ghc I'm not promising that anything will happen fast (unless someone else does it!) but it's always much more likely to happen if there's a specific place that advertises low-hanging performance fruit. This is closely related to the advice to programmers that Don circulated yesterday, in which he explained how he optimised one particular case. But not quite the same. Simon ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Haskell and JVM (was: EclipseFP (Haskell IDE) 0.9.1 released)
Thiago Arrais wrote: There is one issue, though, that touches a lot of sensitive areas. The Eclipse platform runs inside a Java Virtual Machine. Unfortunately, there isn't currently a way to compile Haskell to the JVM (at least I don't know of any, if someone knows, please let me know). This means the IDE has to be written in Java, not in Haskell. That's the price we are paying now. Writing a tool for a language in a different language. Ah, now there's a thing! I don't have any good answers, but I have a friend who is interested in such things, and may even be looking for a project in this area. In our discussions, a number of links came up, but I'm not sure if I can find them all. Here's an attempt: http://www.xoltar.org/languages/nice.html http://www.pugscode.org/ http://scala.epfl.ch/index.html Nothing very specific to your ideas goal, but there's some work on compiling functional code to JVM. I was also talking to someone from Cambridge Comlab the other week who has an FP-like system (for web service/portal creation) that uses JVM bytecode modification. maybe some useful experience to draw upon there? I'm also reminded of a project I was in discussion about some time ago, which was to explore use of Haskell program transformation techniques (hopefully adapting some ideas from BMF/Squiggol) for implementing aspects of a JIT runtime for JVM. Unfortunately, that never took off (and was maybe too ambitious for the effort contemplated). There is some related work at the kestrel Institute [http://www.kestrel.edu/home/projects/] #g -- Graham Klyne For email: http://www.ninebynine.org/#Contact ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re[2]: [Haskell-cafe] EclipseFP (Haskell IDE) 0.9.1 released
Hello Graham, Thursday, February 02, 2006, 1:15:44 PM, you wrote: GK So is there a compelling feature in this Eclipse plugin that isn't easily GK achieved using simpler tools? it's a list of what-i-want-from-the-IDE: * autogeneration of prototypes GK I don't know what you mean by this. adding type signatures of functions to module. this can be done by loading module into the hugs/ghci and using :t; or by the programmatica tools, afair * context help GK Very nice - might persuade me to use Eclipse routinely (I assume you mean things GK like getting help about functions, esp. prelude and standard libraries) yes. btw, if you need it, you can use hasktags with a vim/emacs. it allows you to jump right to the fucntion definition, which is more informative and anyway typically contains text for the haddock. vim even can show this function definition in the supplementary window without jumping to it * type-based function hierarchy browsing GK Very nice. I assume this allows functions to be located from type signatures, GK including prelude and standard libraries. seems that we say about different things. IDEs for OOP languages show program hierarchy around the defined classes, that is unuseful for Haskell. nevertheless, many functions typically grouped around types they support. so, a module-type-function view and type-function view should be handy GK In summary, I think there's enough there to make me think seriously about using GK Eclipse for Haskell development, at least some of the time. sorry, i said about ideal IDE, not about Eclipse (what i never seen, after all). and of course i'm not the author of this package. sorry :))) GK Something I'd also like is in-editor warnings of features that are not supported GK uniformly across different implementations -- my (rough) criteria for portable GK Haskell has been to check that code runs with GHC and Hugs. one thing that i skipped in my dream list is on-the-fly syntax checking GK Also, some form of integrated testing support would be nice. There was brief GK discussion here some time ago about something like assert statements that could GK be checked at compile time -- if you have in-context expression evaluation then GK this wouldn't be a great leap: e.g. scan the code for identifiable expressions GK that are expected to be true, and report warnings if they are not. good idea. i think that i should place all our stuff at the IDE/Ideal wiki -- Best regards, Bulatmailto:[EMAIL PROTECTED] ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Haskell and JVM
Hello, I stumbled upon your discussion on haskell-cafe and this theme seems to pop up one time or another. If someone is interested, I have some Java code for compiling Haskell98 to bytecode that I would be more than willing to share. It is not in the best shape and does not implement all of haskell but most low-level work to generate classes and bytecode from haskell code is implemented (patternmatching, data constructors, lazy functions, ...). This is a project I started some years ago and used for specification of simple functional behaviour (without complex type system) in Java. Regards, -- Arnaud Bailly, Dr. - Ingénieur de Recherche NORSYS 1, rue de la Cense des Raines ZAC du Moulin 59710 ENNEVELIN Tel : (33) 3 28 76 56 76 Mob : (33) 6 17 12 19 78 Fax : (33) 3 28 76 57 00 Web : http://www.norsys.fr ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Haskell and JVM
Hi, up one time or another. If someone is interested, I have some Java code for compiling Haskell98 to bytecode that I would be more than willing to share. It is not in the best shape and does not implement You might also be interested in: http://www.brianweb.net/personal/blog/entry.php?id=18 Currently this is only a runtime, which allows running full Haskell in a JVM. A bytecode translator was being worked on, although I don't know the progress that has been made recently. Thanks Neil ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Haskell and JVM
Questions about Haskell for JVM or .NET was asked quite often and it is really interesting question. Since the JVM and .NET machines have a lot of common if there was a compiler for one of them then it can retargeted to the other quite easily. The major problem with such compilers is the performance. Many attempts exists but no one has managed to build a complete solution. There are several major problems: - How to represent the G/STG machine stack in JVM/.NET? The naive solution is to use an array but it is proven to be inefficient. - How to minimize the runtime typecasts? They are necessary because the JVM/.NET type system is a lot weaker than the Haskell's one. - How to efficiently represent the IO monad and exceptions? - How to make the integration of Haskell with Java/C# easier? Since usually the performance of all VM languages is worse than those of the native compiled (C/C++), I think that it is acceptable for Haskell for JVM/.NET to be slower than GHC for example. Even that if the performance isn't so worse then it will be usable since it can be used in existing Java/.NET projects. Cheers, Krasimir 2006/2/2, Arnaud Bailly [EMAIL PROTECTED]: Hello, I stumbled upon your discussion on haskell-cafe and this theme seems to pop up one time or another. If someone is interested, I have some Java code for compiling Haskell98 to bytecode that I would be more than willing to share. It is not in the best shape and does not implement all of haskell but most low-level work to generate classes and bytecode from haskell code is implemented (patternmatching, data constructors, lazy functions, ...). This is a project I started some years ago and used for specification of simple functional behaviour (without complex type system) in Java. Regards, -- Arnaud Bailly, Dr. - Ingénieur de Recherche NORSYS 1, rue de la Cense des Raines ZAC du Moulin 59710 ENNEVELIN Tel : (33) 3 28 76 56 76 Mob : (33) 6 17 12 19 78 Fax : (33) 3 28 76 57 00 Web : http://www.norsys.fr ___ 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] Re: Haskell code for this example of flow control
Donald Bruce Stewart wrote:
briqueabraque:
Hi,
I would like to know what options I have in Haskell to do something
similar to this C++ code:
double a = 1000;
while (a1) a/=2;
I'm able to do that with lists, but I would like to know how to do
that with monads and variables with state.
You'll get good code using a normal recusive loop:
main = print (loop 1000)
where
loop a | a = 1= a
| otherwise = loop (a/2)
All such control structures may be implemented using recursion.
-- Don
I understand those examples, but I really would like to know how to
do that with monads. I would like to ask the same question, but now with
this code:
double a = 1000;
double b = 0;
while (a != b) {
a /= 2;
cout a; // Prints a
cin b; // User gives a number, stored in b
};
Best,
Maurício
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Re: [Haskell-cafe] Re: Haskell code for this example of flow control
Maurício wrote:
I understand those examples, but I really would like to know how to do
that with monads. I would like to ask the same question, but now with
this code:
double a = 1000;
double b = 0;
while (a != b) {
a /= 2;
cout a; // Prints a
cin b; // User gives a number, stored in b
};
A close to line-for-line translation:
import Data.IORef
import Control.Monad(liftM2,when)
main = example 1000
example :: Double - IO ()
example originalA = do
refA - newIORef originalA -- allocate local variable a
refB - newIORef 0 -- allocate local variable b
let loop = do -- loop in scope of refA, refB
flag - liftM2 (/=) (readIORef refA) (readIORef refB)
when flag $ do
modifyIORef refA (/2)
print = readIORef refA
-- This will give an error if not a number:
writeIORef refB = readIO = getLine
loop
loop -- start executing loop
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Re: [Haskell-cafe] Known Unknowns
--- Ketil Malde [EMAIL PROTECTED] wrote: Isaac Gouy [EMAIL PROTECTED] writes: Programmer skill and effort really does matter ;-) Yes, more so, than any inherent language disadvantage, perhaps, which happens to be the general lesson from the ICFP contests as well. Any idea if other languages have seen similar efforts? FreePascal and Smart Effiel, somewhat - and there have been excellent individual efforts with Lua and Tcl and ... imo the Haskell Cafe discussions and wiki have been a more open and shared learning experience than we usually see, and maybe some of the success stems from that collaboration and competition. __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Re: Haskell code for this example of flow control
On 2/2/06, Maurício [EMAIL PROTECTED] wrote:
I understand those examples, but I really would like to know how to
do that with monads. I would like to ask the same question, but now with
this code:
double a = 1000;
double b = 0;
while (a != b) {
a /= 2;
cout a; // Prints a
cin b; // User gives a number, stored in b
};
An idiomatic approach:
example :: Double - Double - IO ()
example a b
| a == b= return ()
| otherwise = do
let a' = a / 2
print a'
b' - readLn
example a' b'
main = example 1000 0
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Re: [Haskell-cafe] Number 1, at least for now
Am Mittwoch, 1. Februar 2006 08:22 schrieb Donald Bruce Stewart: Haskell is now ranked number 1 on the Great Language Shootout! http://shootout.alioth.debian.org/gp4/benchmark.php?test=alllang=all Hooray :) -- Don It seems to be number 2 at the moment. Best wishes, Wolfgang ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Number 1, at least for now
Am Donnerstag, 2. Februar 2006 04:26 schrieb Donald Bruce Stewart: [...] A good packed string regex library would also be useful. But only one that gives us regular expressions which are parsed at compile time instead of runtime. [...] Best wishes, Wolfgang ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Number 1, at least for now
On 2/2/06, Wolfgang Jeltsch [EMAIL PROTECTED] wrote: Am Mittwoch, 1. Februar 2006 08:22 schrieb Donald Bruce Stewart: Haskell is now ranked number 1 on the Great Language Shootout! http://shootout.alioth.debian.org/gp4/benchmark.php?test=alllang=all Hooray :) -- Don It seems to be number 2 at the moment. It looks like it, all of a sudden, has one missing benchmark. Did something break? /S -- Sebastian Sylvan +46(0)736-818655 UIN: 44640862 ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Number 1, at least for now
--- Sebastian Sylvan [EMAIL PROTECTED] wrote: It seems to be number 2 at the moment. It looks like it, all of a sudden, has one missing benchmark. Did something break? Previously the GHC program was shown incorrectly as completing regex-dna within the timeout - now it's shown correctly. __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Known Unknowns
Joel Koerwer wrote: Don, that's a great little mini tutorial, exactly what I was hoping for. I'm looking forward to learning more tricks. On an unrelated note, I have an STUArray nbody. I haven't really looked closely at the chris+dons version, but I suspect they amount to doing the same thing. I get commensurate runtimes at least. But I'll post it on the wiki in a while in case there is some optimization I missed. On an even more unrelated note, I get slower runtimes with -optc-O3 and -optc-ffast-math than without. Individually or in tandem. Odd. This is ghc 6.4.1 and gcc 4.0.3 on a (Banias) Pentium M. More architecture benchmarking: On a powerbook G4, Joel Koerwer's entry on http://haskell.org/hawiki/NbodyEntry runs faster than dons+chris. And I edited it to make it smaller, but by hoisting 'size' and 'dt' I also made it run quite a bit faster. It now takes 1.7x less time than dons+chris. Don, could you check the speed on your architecture? -- Chris ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Known Unknowns
haskell: Joel Koerwer wrote: Don, that's a great little mini tutorial, exactly what I was hoping for. I'm looking forward to learning more tricks. On an unrelated note, I have an STUArray nbody. I haven't really looked closely at the chris+dons version, but I suspect they amount to doing the same thing. I get commensurate runtimes at least. But I'll post it on the wiki in a while in case there is some optimization I missed. On an even more unrelated note, I get slower runtimes with -optc-O3 and -optc-ffast-math than without. Individually or in tandem. Odd. This is ghc 6.4.1 and gcc 4.0.3 on a (Banias) Pentium M. More architecture benchmarking: On a powerbook G4, Joel Koerwer's entry on http://haskell.org/hawiki/NbodyEntry runs faster than dons+chris. And I edited it to make it smaller, but by hoisting 'size' and 'dt' I also made it run quite a bit faster. It now takes 1.7x less time than dons+chris. Don, could you check the speed on your architecture? Yes! I was missing the -funbox-strict-fields, it makes a huge difference. Check the wiki page, these stuarrays are the fastest yet. Cheers, Don ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Haskell to call Microsoft COM (Dispatch)
On Mon, Jan 30, 2006 at 08:40:43PM +0100, Gracjan Polak wrote: Hi all, Is there any library to make Haskell call Microsoft COM functions using Dispatch? E.g I don't need the full COM binary functionality, scripting is enough. Google didn't seem to find anything interesting... beside rolling my own using FFI :) Thanks in advance! Hi. I spent much time trying to get it to work.. you have to download the whole fptools directory (from cvs!).. and I think i did some little patches but I can check out again and compare.. It did compile and I think it's working well but I'm still struggling getting to use it.. At least the examples do compile! If you are really interested I would appreciate getting in contact with you (my private email: marco-oweber a t gmx.de) .. Perhaps we can help each other. (Becaue I'm not an experienced haskell programmer, yet ;-) Marc ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Known Unknowns
Hey this is great. Chris your improvements are awesome. I mean the speed is nice, but you really cleaned up the code. There's an extraneous call to energy in the second runST block, but it should be insignificant. Also, -fglasgow-exts is necessary for the left-hand-side type declarations of size and dt. One question, in: calcMomentum (i+1) $! (px+vx*m,py+vy*m,pz+vz*m) that $! doesn't actually do much for a tuple, does it? Of course, there's not much point in further optimizing the initialization routine, as we'd never be able to detect the difference in runtime. The shootout has been a great learning tool for me :-) Thanks to Chris, Don, and the rest of the Haskell community. Joel ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
