Re: [Haskell-cafe] What *not* to use Haskell for
You can hire one Haskell programmer instead of 1,2,3... programmers in your favorite imperative language. On Tue, Nov 11, 2008 at 12:32 PM, Arnar Birgisson [EMAIL PROTECTED] wrote: Hi all, On Tue, Nov 11, 2008 at 11:38, Dave Tapley [EMAIL PROTECTED] wrote: Usually I'll avoid then question and explain that it is a 'complete' language and we do have more than enough libraries to make it useful and productive. But I'd be keen to know if people have any anecdotes, ideally ones which can subsequently be twisted into an argument for Haskell ;) I would not use Haskell if I were faced with the prospect of producing a huge system in short time (i.e. meaning I couldn't do it by myself) and all I had was a pool of regular programmers that have been trained in .NET, Java, C++, Python, your favorite imperative language. Yes, sad - but true. I'd very much like to see this twisted to an argument for Haskell :) cheers, Arnar ___ 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] Efficient parallel regular expressions
Hi Martijn, If you are brave to start implementing DFA with all required optimisations then you might want to look at: http://www.ontotext.com/gate/japec.html This is a compiler for language called JAPE. In the language you define a set of rules where the right hand side is a regular expression and the left hand side is a Java code. The compiler itself is implemented in Haskell. It includes code to build DFA from the set of regexps and then it does determinization and minimization. I wrote the compiler few years ago. You can decide to take and change the code or to reimplement it yourself. Definitely DFA guarantees that the performance is always linear while with Parsec you have to be careful. Regards, Krasimir On Tue, Nov 4, 2008 at 6:05 PM, Martijn van Steenbergen [EMAIL PROTECTED] wrote: Hello all, For my mud client Yogurt (see hackage) I'm currently working on improving the efficiency of the hooks. Right now several hooks, each consisting of a regex and an action can be active at the same time. Every time a line of input is available (usually several times a second) I run the line through all the available regexes and execute the first matching action. I figured this is not the cleverest approach and it'd be better if I |'ed all regexes into one big DFA. However, how do I then find out which of the original hooks matched and so which action to execute? As far as I know there's no way to do that with Text.Regex. Alex looks promising but is really only an executable and doesn't offer an API. I've also found mr. João Saraiva's HaLex but I don't know if that was meant to be used seriously. Does anyone have any experience with this? What's the best way to achieve this? Thanks much, Martijn. ___ 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] two problems with Data.Binary and Data.ByteString
On Wed, Aug 13, 2008 at 1:18 AM, Don Stewart [EMAIL PROTECTED] wrote: instance Binary a = Binary [a] where put l = put (length l) mapM_ put l get= do n - get :: Get Int replicateM n get Of course I changed this as well. Now it is: instance (Ord k, Binary k, Binary e) = Binary (Map.Map k e) where put m = put (Map.size m) mapM_ put (Map.toAscList m) get = liftM Map.fromDistinctAscList get You don't have to convert the map to list just to compute its size. The Map.size is a O(1) function. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] two problems with Data.Binary and Data.ByteString
I had the same problem (stack overflow). The solution was to change the = operator in the Get monad. Currently it is: m = k = Get (\s - let (a, s') = unGet m s in unGet (k a) s') but I changed it to: m = k = Get (\s - case unGet m s of (a, s') - unGet (k a) s') It seems that the bind operator is lazy and this caused the stack overflow. I have also another problem. Every Int and Word is stored as 64-bit value and this expands the output file a lot. I have a lot of integers and most of them are 128 but not all of them. I changed the serialization so that the Int and Word are serialized in a variable number of bytes. Without this change the binary serialization was even worse than the textual serialization that we had before. The file was almost full with zeros. I just haven't time to prepare a patch and to send it for review but if other people have the same problem I will do it. Best Regars, Krasimir On Wed, Aug 13, 2008 at 1:13 AM, Tim Newsham [EMAIL PROTECTED] wrote: I have a program that read in and populated a large data structure and then saved it out with Data.Binary and Data.ByteString.Lazy.Char8: saveState db = B.writeFile stateFile = encode $ atomically (readTVar db) when I go to read this in later I get a stack overflow: loadState db = do d - decode $ B.readFile stateFile atomically $ writeTVar db d Stack space overflow: current size 8388608 bytes. Use `+RTS -Ksize' to increase it. or from ghci: d - liftM decode (Data.ByteString.Lazy.Char8.readFile savedState.bin) :: IO InstrsDb fromList *** Exception: stack overflow The data type I'm storing is a Map (of maps): type DailyDb = M.Map Date Daily type InstrsDb = M.Map String DailyDb What's going on here? Why is the system capable of building and saving the data but not in reading and umarhsalling it? What is the proper way to track down where the exception is happening? Any debugging tips? I also noticed another issue while testing. If my program loads the data at startup by calling loadState then all later calls to saveState give an error: Log: savedState.bin: openFile: resource busy (file is locked) this does not occur if the program wasnt loaded. My best guess here is that B.readFile isnt completing and closing the file for some reason. Is there a good way to force this? Tim Newsham http://www.thenewsh.com/~newsham/ ___ 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] Darcs / Git
I use darcs on Windows every day and it works well. The only problem is that it is not very usable if you access your repository via SSH and the authentication is via password. On Mon, Oct 6, 2008 at 9:11 PM, Dominic Steinitz [EMAIL PROTECTED] wrote: Not really a Haskell question but I'm not sure where else to go. What's the preferred method of converting a darcs repository to git? And is there a way of converting from git to darcs? The reason I ask is that my colleague cannot get darcs to work on his Windows box. Thanks, Dominic. ___ 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] Haskell versus F#, OCaml, et. al. ...
On Tue, Sep 30, 2008 at 8:46 AM, Don Stewart [EMAIL PROTECTED] wrote: There's almost 800 Haskell libraries on hackage.haskell.org (millions of lines of code). On average, 2 new libraries are released each day (though 12 new libs were released in the last 24 hours). That's 700 new libraries a year at the current rate. This is missleading and depends on how you count the libraries. For instance base is now split into arrays, containers, process, parallel etc. In the same time on platforms like Java and .NET this might be only one package. Krasimir ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Unboxing VT_VARIANT in hscom
Aha. I got it. You should compile with -fglasgow-exts option. The
extra type signatures doesn't matter.
On Wed, Aug 20, 2008 at 8:20 AM, Praki Prakash [EMAIL PROTECTED] wrote:
Krasimir - thanks for your reply. I had tried explicit typing but I still
get the same error. I have some code below and the error message.
import Control.Exception
import Foreign
import Foreign.COM.Client
import Foreign.COM.Automation
import System.IO
data WmiConnection =
WmiConnection {
execQuery :: String - IO ()
}
main = withCOM $ do
conn - wmiconnect . root\\cimv2
execQuery conn Select * From ...
print done
wmiconnect :: String - String - IO WmiConnection
wmiconnect comp cimroot =
do
clsid - progid2clsid WbemScripting.SWbemLocator
(bracket (createInstance clsid iidIUnknown) release $ \iunkn -
bracket (queryInterface iidIDispatch iunkn) release $ \idisp - do
dispId - getMethodID ConnectServer idisp
withBSTR comp $ \pComputer -
withBSTR cimroot $ \pCimRoot - do
(res,args) - invoke dispId InvokeMethod [Variant VT_BSTR
pComputer,
Variant VT_BSTR
pCimRoot
] idisp
print res
let conn = WmiConnection{ execQuery = queryFunc res }
return conn)
where
queryFunc :: Variant - String - IO ()
queryFunc (Variant VT_DISPATCH idisp) query = do
dispId - getMethodID ExecQuery idisp
return ()
{-
queryFunc (Variant vt idisp) query =
if vt == VT_DISPATCH
then do
dispId - getMethodID ExecQuery idisp
return
else
fail error
return ()
-}
C:\ghc --make test.hs
[1 of 1] Compiling Main ( test.hs, test.o )
test.hs:35:47:
Couldn't match expected type `IDispatch a'
against inferred type `a1'
`a1' is a rigid type variable bound by
the constructor `Variant' at test.hs:34:22
In the second argument of `getMethodID', namely `idisp'
In a 'do' expression: dispId - getMethodID ExecQuery idisp
In the expression:
do dispId - getMethodID ExecQuery idisp
return ()
Any further suggestions?
Thanks,
Praki
On Tue, Aug 19, 2008 at 1:49 AM, Krasimir Angelov [EMAIL PROTECTED]
wrote:
This looks like a GHC bug to me. I am pretty sure that this worked
before. Variant is defined like this:
data Variant = forall a . Variant (VarType a) a
data VarType a where
VT_DISPATCH :: VarType (IDispatch ())
From this it clear that val is of type (IDispatch ()) because the
VarType has value VT_DISPATCH. A workaround is to add explicit type
singnature for val:
someFunc (Variant VT_DISPATCH val) query = do
dispId - getMethodID MethodName (val :: IDispatch ())
I don't know why this doesn't work without the signature.
Regards,
Krasimir
On Tue, Aug 19, 2008 at 7:09 AM, Praki Prakash [EMAIL PROTECTED]
wrote:
I am a Haskell newbie trying to do COM automation using Haskell. I am
using
hscom (Krasimir's implementation of COM automation). I have run into a
problem
and need some help.
I have a Variant returned from a COM method invocation. When I print it,
it
shows up as below.
Variant VT_DISPATCH interface 0x00039f00
I need to invoke methods on the wrapped interface. My attempt to unbox
it as
below runs into 'rigid type' error.
someFunc (Variant VT_DISPATCH val) query = do
dispId - getMethodID MethodName val
The code above generates this error.
Couldn't match expected type `IDispatch a'
against inferred type `a1'
`a1' is a rigid type variable bound by...
I am probably missing something pretty basic. Any help on this is
greatly
appreciated!
Thanks
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[Haskell-cafe] Re: [Haskell] Compiler Construction course using Haskell?
Hi Johannes, There is a similar course in Chalmers. The home page is here: http://www.cs.chalmers.se/Cs/Grundutb/Kurser/progs/current/ There students were required to implement full parser, partial typechecker and partial interpreter for C++ in either C++, Java or Haskell. We used BNFC for the parser: http://www.cs.chalmers.se/Cs/Research/Language-technology/BNFC/ which was easier for most students I think. In any way I would recomend Happy+Alex or BNFC instead of Parsec but this is only my personal preference. Best Regards, Krasimir 2008/8/20 Johannes Waldmann [EMAIL PROTECTED]: Hello. I plan to give a course in compiler construction, using Haskell as the implementation language (not as source or target language). Something along these lines: 1. combinator parsers (Parsec), 2. simple interpreter (arithmetical expressions) 3. add algebraic data types, functions 4. type checker 5. code generator. Ideally, 2..5 would be using the very same tree traversal code and just change the monad for evaluation. Any comments appreciated. Have you given such a course? Taken? If I really decide to do it, then slides (in German) will be made available. Best regards, J.W. ___ Haskell mailing list [EMAIL PROTECTED] http://www.haskell.org/mailman/listinfo/haskell ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Unboxing VT_VARIANT in hscom
This looks like a GHC bug to me. I am pretty sure that this worked before. Variant is defined like this: data Variant = forall a . Variant (VarType a) a data VarType a where VT_DISPATCH :: VarType (IDispatch ()) From this it clear that val is of type (IDispatch ()) because the VarType has value VT_DISPATCH. A workaround is to add explicit type singnature for val: someFunc (Variant VT_DISPATCH val) query = do dispId - getMethodID MethodName (val :: IDispatch ()) I don't know why this doesn't work without the signature. Regards, Krasimir On Tue, Aug 19, 2008 at 7:09 AM, Praki Prakash [EMAIL PROTECTED] wrote: I am a Haskell newbie trying to do COM automation using Haskell. I am using hscom (Krasimir's implementation of COM automation). I have run into a problem and need some help. I have a Variant returned from a COM method invocation. When I print it, it shows up as below. Variant VT_DISPATCH interface 0x00039f00 I need to invoke methods on the wrapped interface. My attempt to unbox it as below runs into 'rigid type' error. someFunc (Variant VT_DISPATCH val) query = do dispId - getMethodID MethodName val The code above generates this error. Couldn't match expected type `IDispatch a' against inferred type `a1' `a1' is a rigid type variable bound by... I am probably missing something pretty basic. Any help on this is greatly appreciated! Thanks ___ 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] ActiveX and COM
Hi Günther, You can also consider the hscom library: http://darcs.haskell.org/packages/hscom/ There is a simple demo that automates MS Agent. The library is not completed but if you are interested only in controlling Excel via automation it should provide what you need. I started hscom because I was disappointed from HDirect while working on Visual Haskell. It overcomes some problems and in addition it is designed to be more in the style of the modern FFI library. The library is not under active development but I can assist with simple fixes. Regards, Krasimir On Mon, Aug 4, 2008 at 11:47 AM, GüŸnther Schmidt [EMAIL PROTECTED] wrote: Hi, what is currently the recommend way to interface with COM from haskell? I need to create an Excel Sheet and thus need to use Excel via COM. Günther ___ 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] Scripting COM Components from Haskell - GreenCard on Hackage
No! Greencard is another story. The paper describes HDirect. On Tue, Aug 5, 2008 at 3:02 PM, GüŸnther Schmidt [EMAIL PROTECTED] wrote: Hi, does anybody know if the Greencard package / lib is the same software that is mentioned in the paper Scripting COM Components from Haskell? http://research.microsoft.com/~simonpj/papers/com.ps.gz I managed to install the hackage Greencard package on XP with GHC 6.8.3 but it seems to be quite different from what the paper describes. Günther ___ 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] Implementing ParseChart with Data.Map
I actually made my own copy of Data.Map and added an extra: alterLookúp :: Ord k = (Maybe a - (b,Maybe a)) - k - Map k a - (b,Map k a) function. I also changed my data type to: type ParseChart k v = Map k (Map v ()) so I don't have to copy the Data.Set module also. Unfortunately this doesn't give much better performance - 5734 msec instead of 5828 msec. Fortunately I found that there is a way to avoid to use Map at all in one common case. This gave me time about 5024 msec. Regards, Krasimir On 6/3/08, Yitzchak Gale [EMAIL PROTECTED] wrote: Krasimir Angelov wrote: but notice that the set is still traversed twice. Neil Mitchell wrote: I don't see any way of reducing that Yeah, it looks like the Data.Set (and Data.IntSet) library is missing the functions insertMember :: Ord a = a - Set a - (Bool, Set a) deleteMember :: Ord a = a - Set a - (Bool, Set a) analagous to splitMember. It should be easy to write those functions. If you do that for yourself, consider making a patch of them and submitting the patch as a library proposal. But anyway, a set lookup is very cheap, even for a set that is quite large. You may want to try just doing the extra lookup, it might be good enough for you. At least you eliminated the Map lookup. Regards, Yitz ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Implementing ParseChart with Data.Map
Hi, I have to write ParseChart implementation with Data.Map/Set. The chart is type like this: type Chart k v = Map k (Set v) now I need operation like: insert :: k - v - Chart k v - Maybe (Chart k v) where the result is (Just _) if the (k,v) is actually added to the chart or Nothing if it was already there and nothing have to be done. The straight forward implementation is: case Map.lookup k chart of Nothing - Just (Map.insert k (Set.singleton v) chart) Just set | Set.member v set - Nothing | otherwise- Just (Map.insert k (Set.insert v set) chart) The problem with this is that both the Map and the Set are traversed twice. The first time from lookup/member and the second time from insert. Does someone have an idea how to do this with the current libraries? There are the Map.updateLookupWithKey and the Map.alter functions: updateLookupWithKey :: Ord k = (k - a - Maybe a) - k - Map k a - (Maybe a,Map k a) alter :: Ord k = (Maybe a - Maybe a) - k - Map k a - Map k a which are the closest that I need. The problem is that the first doesn't allow the client function to be called if there isn't matching key in the map and the second is doesn't allow to return value from the client function. What I really need is an alterLookúp function: alterLookúp :: Ord k = (Maybe a - (b,Maybe a)) - k - Map k a - (b,Map k a) The chart manipulation is in the tight loop of my application so I need fast code. Any other ideas? Regards, Krasimir ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Implementing ParseChart with Data.Map
Not completely! This is a possible implementation: case insertLookupWithKey (\_ - Set.union) k (Set.singleton v) chart of (Nothing, chart) - Just chart (Just set, chart) | Set.member v set - Nothing | otherwise - Just chart but notice that the set is still traversed twice. On Tue, Jun 3, 2008 at 12:07 AM, Neil Mitchell [EMAIL PROTECTED] wrote: Hi Krasimir, insert :: k - v - Chart k v - Maybe (Chart k v) where the result is (Just _) if the (k,v) is actually added to the chart or Nothing if it was already there and nothing have to be done. insertLookupWithKey :: Ord k = (k - a - a - a) - k - a - Map k a - (Maybe a, Map k a) This should provide the information you need, without the double traversal of the data structure. Thanks Neil ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Data.Tree.Zipper in the standard libraries
Hi again, I was silent for some time but in this time I created QuickCheck tests for Data.Tree.Zipper which achieve 100% coverage with HPC. I also created a ticket for it: Ticket #2324 http://hackage.haskell.org/trac/ghc/ticket/2324 The attached file is the current implementation and it contains the version updated from Iavor Diatchki. It has the advantage that it also works with forests, not just with trees. Initially I thought that complete testsuite for such a simple module might be overkill but actually I found a bug :-) in the splitChildren function which is now fixed. The dead line for further considerations is one week. Regards, Krasimir On Sun, May 25, 2008 at 1:09 AM, Iavor Diatchki [EMAIL PROTECTED] wrote: Hello, I think that the modified API (no state monad, and using Maybe) is quite nice! I implemented a version of the the suggested API using a slightly different data structure, which makes the code a bit simpler, I think. I put the code in the Haskell wiki: http://www.haskell.org/sitewiki/images/2/2d/RoseZipper.hs I also added a couple of extra functions that seemed useful, and renamed a few of the functions to be more consistent. As for how to distribute the code, it seems that Zipper should live in the same place as Data.Tree. I think that Data.Tree is part of the containers package, so it would make sense to add the Zipper there as well. -Iavor On Sat, May 24, 2008 at 1:24 AM, Neil Mitchell [EMAIL PROTECTED] wrote: Hi, It doesn't use State monad anymore and it returns Maybe. This seems to be the common preference, is it? Feel free to vote against. Should we change Data.Map also? There is another proposal for changes in findMin/findMax so it is better to make this two breaking changes together rather than in a later release. The standard libraries proposal thingy is to go via the libraries list, create tickets etc. What reason is there to make this part of the base libraries, rather than a separate package on hackage? I can't see much reason to make Data.Tree part of the base libraries, other than the fact it already is, and it could easily get moved out at a future date. We've seen there is some advantage in leaving the implementation outside the base library, as its already changed several times in the past few days. Thnanks Neil ___ 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] Data.Tree.Zipper in the standard libraries
Aha. I see the point. The current design was influenced from some other implementation that I spot somewhere in the net. I will change it but this reminds me of another problem. Most movement functions raise error if they can't do the movement. This is convenient if you somehow know that the direction in which you go always exists. Alternatively I can use monad with failure. In other words, there are two possibilities: 1. Use error .. and types like: TreeLoc a - TreeLoc a 2. Use monad and type like: Monad m = TreeLoc a - m (TreeLoc a) In the second case some one have to do something like this to check whether the operation is successful: case left loc of Noting - error something gone wrong Just loc - ... In the first case there is no way to check for success but someone can use precondition: if isFirst loc then do_something (left loc) else i_cannot_go_left In my opinion 1 looks nicer but 2 also have advantages. What do you think? Regards, Krasimir On Fri, May 23, 2008 at 12:33 AM, Conal Elliott [EMAIL PROTECTED] wrote: * Every definition of tp I meant of type, forgetting that my emacs abbrevs don't expand in gmail. On Thu, May 22, 2008 at 2:13 PM, Conal Elliott [EMAIL PROTECTED] wrote: Hi Krasimir, I had a long exchange with chessguy about this interface, suggesting a significant change in style, simplifying the type. (Incidentally, the change removed the State and hence mtl dependence.) The conversation is on http://tunes.org/~nef/logs/haskell/08.05.17, starting with 12:08:11 chessguy w00t! and really picking up with conal chessguy: something smells funny Here's a summary of the conversation, though I encourage you to read the whole thing: * Every definition of tp 'State (TreeLoc a) a', does a getLabel at the end (except getLabel). * Often users of those movement functions discard the result. * Simpler and more orthogonal would be remove the getLabel and return 'State (TreeLoc a) ()' instead. * Now remove that return value altogether, simplifying the type of zipper movements to just 'TreeLoc a - TreeLoc a'. Then they compose nicely with (.), having id as identity. * Simplify the type of getLabel to just 'TreeLoc a - a'. Now no more State. Cheers, - Conal On Thu, May 22, 2008 at 12:52 PM, Krasimir Angelov [EMAIL PROTECTED] wrote: Hello Guys, We have Data.Tree in the standard libraries for a long time but for some reason we still don't have standard implementation for Zipper. I wrote recently one implementation for Yi but there are many other versions hanging around. At least I know for some. I propose to add one in the standard libraries i.e. the containers package. The version that I use currently is here: http://code.haskell.org/yi/Data/Tree/Zipper.hs If you would like to do code review I will be happy to hear comments. After the API is settled down I will write test cases also. One thing that is worying me is that the current version uses State monad which is in the mtl package while the natural place for Data.Tree.Zipper is in containers. This will create an extra dependency. Is this acceptable? Regards, Krasimir ___ 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] Data.Tree.Zipper in the standard libraries
Hello Guys, We have Data.Tree in the standard libraries for a long time but for some reason we still don't have standard implementation for Zipper. I wrote recently one implementation for Yi but there are many other versions hanging around. At least I know for some. I propose to add one in the standard libraries i.e. the containers package. The version that I use currently is here: http://code.haskell.org/yi/Data/Tree/Zipper.hs If you would like to do code review I will be happy to hear comments. After the API is settled down I will write test cases also. One thing that is worying me is that the current version uses State monad which is in the mtl package while the natural place for Data.Tree.Zipper is in containers. This will create an extra dependency. Is this acceptable? Regards, Krasimir ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] zipper for rose trees? (Data.Tree)
Hi Graham, There is one implementation here: http://code.haskell.org/yi/Data/Tree/ I wrote it for Yi but it is quite general. It is a pity that we don't have it in the standard libraries. It is not completely tested but it seems to work for me. Regards, Krasimir 2008/4/23 Graham Fawcett [EMAIL PROTECTED]: Hi folks, Is there a common zipper implementation for the Tree a datatype, defined in Data.Tree? The wiki gives examples for binary trees and B-trees, but not for these. Thanks, Graham ___ 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] Tools for Haskell and COM
There's a bit of a chicken-and-egg problem here; the COM tools are not well maintained, so that discourages use, which in turn makes it less rewarding to work on them. What I don't know is the level of suppressed demand: if there were good tools, would lots of people start using them? I think it will be beneficial for many Windows user if there was a good Haskell to COM integration. HDirect can be a real nightmare for a large projects. The first step could be to build a new COM library designed in more FFI addendum fashion. I already have started the first step with: http://darcs.haskell.org/packages/hscom/ It is far from complete of course. The second step should be to reimplement the IDL-Haskell translator. The existing translator often generate code that isn't type correct and even if you change the code by hand there is still a chance to have an implementation errors which can't be captured from the typechecker. The whole task isn't that hard but still requires a volunteer willing to spend 2-3 months of full time work. Regards, Krasimir ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Re: GHC throws IOError on Win32 when there is no console
On 2/13/07, Simon Marlow [EMAIL PROTECTED] wrote: Sounds like a good idea. You need to look at rts/RtsMessages.c, in particular rtsErrorMsgFn(), which currently has cases for GUI and non-GUI. I guess it really should have 3 cases: GUI, console, and non-GUI. The trick here is how to find whether the current application is GUI, console or non-GUI. The distinction between GUI and Console applications is easy because you can check subsystem OS type. This doesn't work with Windows services because they can be either GUI or Console. The OS is preventing them from showing any windows. Cheers, Krasimir ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] How to serialize thunks?
Hi Joachim, All those libraries really force the data because they all are written in Haskell. If you want to serialize thunks then you will need some support from RTS. This is something that is implemented in Clean but this just uncovers a lot of other problems: The serialization of thunk requires to store a reference to procedure for thunk evaluation. After that it is tricky to do the deseriazation because you will have to dynamically link the thunk evaluation code. The program that do the serialization and the program that have to read it aren't necessary one and the same program. In this case the reading application should have some way to call code from the writing application. Another problem arises when you have to recompile the writing application. After the recompilation the evaluation code for some thunk may not exist any more. The solution that Clean is using is to keep a copy of each executable after each compilation. Cheers, Krasimir On 12/21/06, Joachim Durchholz [EMAIL PROTECTED] wrote: I have skimmed the serialization libraries on haskell.org (NewBinary, SerTH, AltBinary, HsSyck, GenericSerialize). I'm under the impression that these all force the data that they serialize. Is that correct? If yes: are there workarounds? I'd really like to be able to use infinite data structures in the data that I serialize. Regards, Jo ___ 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: How to serialize thunks?
On 12/21/06, Joachim Durchholz [EMAIL PROTECTED] wrote: Krasimir Angelov schrieb: All those libraries really force the data because they all are written in Haskell. If you want to serialize thunks then you will need some support from RTS. Good to hear that my conjectures aren't too far from reality. Does any Haskell implementation have that kind of RTS support? Not yet. I ever don't know of anyone planning to do that. Cheers, Krasimir ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Re: Haskell and .NET
The problem with Haskell for .NET is that the produced executables are usually very slow. Good optimizing compiler like GHC has better chance to produce code with reasonable performance. The major problem with YHC is that it still doesn't have strictness analyzer. The consequence is that the produced .NET code creates lots of unnecessary temporal objects. Cheers, Krasimir On 12/13/06, Neil Mitchell [EMAIL PROTECTED] wrote: Hi Yhc also has a .NET generating capability, just pass the -dotnet flag. http://haskell.org/haskellwiki/Yhc Thanks Neil On 12/12/06, Monique Monteiro [EMAIL PROTECTED] wrote: Hi Justin, I've runned a research project about this topic (in fact, it was the subject of my MSc dissertation). Please see the Haskell.NET Project (http://www.cin.ufpe.br/~haskell/haskelldotnet). We have compiled a subset of the Haskell language to .NET, but we still don't have an available release (we don't support the full Haskell prelude yet). The compiler is an extension to GHC. In the future, we intend to provide full interoperability with .NET in this way. There are some interesting references in the website about our compilation strategies. If you need further information about the project's status, please contact Prof. André Santos ([EMAIL PROTECTED]) and/or Guilherme Avelino ([EMAIL PROTECTED]). Best regards, -- _ Monique Monteiro, MSc http://www.cin.ufpe.br/~mlbm http://thespoke.net/blogs/moniquelouise/default.aspx [EMAIL PROTECTED] +55 81 34198137 Project Manager Recife Microsoft Innovation Center ___ 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 mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Re: Haskell and .NET
On 12/13/06, Neil Mitchell [EMAIL PROTECTED] wrote: Hi Krasimir, to produce code with reasonable performance. The major problem with YHC is that it still doesn't have strictness analyzer. It does, or rather Yhc.Core does (see Yhc.Core.Strictness - http://www.cs.york.ac.uk/fp/yhc/snapshot/docs/Yhc-Core-Strictness.html). This was only done a few weeks ago, so the .NET translator has no benefit from it. And strictness is not the biggest problem, a complete lack of any optimisations is, but I'm working on that one too! It is great to hear that. Of course an optimiser will be beneficial too but I guess that even the benefit that the code generator can have from the strictness analyzer will make huge difference. Cheers, Krasimir ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Re: [Haskell] ANNOUNCE: Visual Haskell 0.2 final
It is already bundled with slightly newer version of GHC-6.6. There was a bug that had to be fixed in order to have working Visual Haskell. Visual Haskell is dependent of GHC API and you can't simply use it with different GHC version. Cheers, Krasimir On 12/8/06, Bulat Ziganshin [EMAIL PROTECTED] wrote: Hello Krasimir, Friday, December 8, 2006, 11:12:26 AM, you wrote: The final version of Visual Haskell 0.2 is ready: - distributed with a stable GHC version (6.6) how about bundlng it with up-to-date GHC 6.6 build (which've fixes a lot of problems) or, better, allow to use it with user-installed ghc 6.6.* installation? -- Best regards, Bulatmailto:[EMAIL PROTECTED] ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Re: Re[2]: [Haskell] ANNOUNCE: Visual Haskell 0.2 final
You can replace just libHSrts.a in your Visual Haskell directory and it should work. I will release a new VSHaskell after GHC-6.6.1 release. If the .hi format is still the same in the last GHC-6.6 revision then you should safely replace everything. Cheers, Krasimir On 12/8/06, Bulat Ziganshin [EMAIL PROTECTED] wrote: Hello Krasimir, Friday, December 8, 2006, 4:30:31 PM, you wrote: It is already bundled with slightly newer version of GHC-6.6. There was a bug that had to be fixed in order to have working Visual Haskell. Visual Haskell is dependent of GHC API and you can't simply use it with different GHC version. i mean newr 6.6.* versions, what fixed also other errors, not only VH-related. if my project needs, for example, GC bugfix, i can't use VH because this error was fixed only a few weeks ago -- Best regards, Bulatmailto:[EMAIL PROTECTED] ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Re: [Haskell] ANNOUNCE: Visual Haskell prerelease 0.2
Thanks. In the mail that I mentioned there was a sugesstion to use -s option during dll linking. This has the advantage that the produced dll will be smaller but still correct. I will try to build a new dll again with this option this time. If it works I will prepare a new installer with the updated dll. Cheers, Krasimir On 12/1/06, shelarcy [EMAIL PROTECTED] wrote: Hi Krasimir, On Fri, 01 Dec 2006 16:56:02 +0900, Krasimir Angelov [EMAIL PROTECTED] wrote: http://www.cygwin.com/ml/cygwin/1998-04/msg00133.html I wonder whether this may cause the problem. I have uploaded a new vs_haskell.dll here: http://www.haskell.org/visualhaskell/vs_haskell.zip It is the same dll but without stripped debug symbols. Could you try to replace it in your installation? I tried to replace vs_haskell.dll after Windows Installer (MSI), no error occur during devenv.exe /Setup command or using Visual Haskell. I can make new Haskell project. On Fri, 01 Dec 2006 03:48:49 +0900, Justin Bailey [EMAIL PROTECTED] wrote: I am having similar problems with the Visual Haskell install, and the commands given did not help. When I open Visual Studios Help | About dialog, I get an error about the package failing to initialize. I am installing to an English copy, however. And I can open Studios Help | About dialog without any error. After exit Visual Haskell, Microsoft Development Environment opened error dialog about devenv.dll sometimes. Anyway, this error is harmless and I reported to Microsoft by form. Best Regards, -- shelarcy shelarcycapella.freemail.ne.jp http://page.freett.com/shelarcy/ ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] ANNOUNCE: Visual Haskell prerelease0.2
I will build these libraries for the final installer. On 12/1/06, shelarcy [EMAIL PROTECTED] wrote: Hi Alistair, On Fri, 01 Dec 2006 18:13:45 +0900, Bayley, Alistair [EMAIL PROTECTED] wrote: It certainly is. Is it possible to configure VisualHaskell so that it uses the existing ghc-6.6 installation, rather than it's own? I think you can install extra libraries by cabal (and sometime you also need MSYS and MSYS Developer Tool Kit (autotools) for configuration). cgi fgl GLUT (and GLUT_cbits) haskell-src html HUnit mtl network objectio OpenGL (and OpenGL_cbits) QuickCheck readline time xhtml And I proposed to bundle OpenAL and ALUT packages. http://www.haskell.org/pipermail/glasgow-haskell-users/2006-October/011283.html These packages are in extra libraries. And I think that - OpenAL library is LGPL and OpenAL package is BSD3, so there is no reason avoiding to include this package. OpenAL site notices that OpenAL can become Creative's licese when using on Creative Device. http://www.openal.org/platforms.html But if you look at Creative's OpenAL SDK header files, you can find al.h and eft.h are LGPL. So I think we can use OpenAL library under LGPL on Windows, if we don't use Creative specific extentions. http://opensource.creative.com/pipermail/openal/2004-March/007309.html Best Reagrds, -- shelarcy shelarcycapella.freemail.ne.jp http://page.freett.com/shelarcy/ ___ 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: [Haskell] ANNOUNCE: Visual Haskell prerelease 0.2
The zip file is updated with .dll that is with stripped debug symbols but with --optdll-s as it is recommended. Could some one try whether it works? It is about two times smaller than the non stripped version. http://www.haskell.org/visualhaskell/vs_haskell.zip Cheers, Krasimir ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Re: [Haskell] ANNOUNCE: Visual Haskell prerelease 0.2
Sorry. I was sleeping and I uploaded it to darcs.haskell.org instead to haskell.org. Try it now. Cheers, Krasimir On 12/2/06, shelarcy [EMAIL PROTECTED] wrote: Hi Krasimir, On Sat, 02 Dec 2006 02:14:26 +0900, Krasimir Angelov [EMAIL PROTECTED] wrote: The zip file is updated with .dll that is with stripped debug symbols but with --optdll-s as it is recommended. Could some one try whether it works? It is about two times smaller than the non stripped version. http://www.haskell.org/visualhaskell/vs_haskell.zip Is this file updated one? I downloaded it from above url again. But file size is same. So, I checked hash. It noticed that current and previous files are same. $ md5sum vs_haskell.dll \a968ac130932a9b38bd0da50e9ae865a *C:\\Documents and Settings\\ Administrator\\My Documents\\vs_haskell\\vs_haskell.dll $ md5sum C:\Doc\Haskell\vs_haskell\vs_haskell.dll \a968ac130932a9b38bd0da50e9ae865a *C:\\Doc\\Haskell\\vs_haskell\\ vs_haskell.dll Best Regards, -- shelarcy shelarcycapella.freemail.ne.jp http://page.freett.com/shelarcy/ ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Re: [Haskell] ANNOUNCE: Visual Haskell prerelease 0.2
VSHaskell isn't interfacing with .NET but is a COM server written in Haskell. The VStudio IDE is actually implemented in C but is using COM as an interface to the various plugins. That way you can implement the plugin in C++/.NET/Haskell or what ever you want. For Eclipse you need a bridge between JVM and Haskell. In addition you have find some way to build .so library for Linux. Cheers, Krasimir On 11/30/06, Thiago Arrais [EMAIL PROTECTED] wrote: On 11/30/06, Johannes Waldmann [EMAIL PROTECTED] wrote: The main advantage (Visual Haskell over eclipsefp) at the moment is that VH uses incremental (on-the-fly) typechecking/compilation while eclipsefp calls the compiler for whole modules? I would say this is one of the greatest advantages of VH, don't know if it is the main one, but it surely is an advantage. I wonder how VH achieves that. I imagine it manages to run GHC (it uses GHC, right?) inside the .Net VM or at least access it through some programmatic interface using some kind of native/VM data conversion. GHC code (and not VH code) do the typechecking/compilation tricks. Is that right? Eclipse is Java and I am pretty sure we can do something similar with it and we actually did something like the second approach prior to version 0.9.1, but just for source code parsing. What do we need for that? Cheers, Thiago Arrais -- Mergulhando no Caos - http://thiagoarrais.wordpress.com Pensamentos, idéias e devaneios sobre desenvolvimento de software e tecnologia em geral ___ 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: [Haskell] ANNOUNCE: Visual Haskell prerelease0.2
Hi Alistair, Visual Haskell is packaged with just the core libraries. Control.Monad.* modules are part of mtl and Test.HUnit is part of HUnit which aren't core libraries and aren't installed. It was long time ago when I was using the official Windows installer for last time. Is it still packaged with all libraries? Krasimir On 11/30/06, Bayley, Alistair [EMAIL PROTECTED] wrote: (not sure if this is the best place for questions about VisualHaskell) I've just installed VisualHaskell, and I've noticed that some of the hierarchical libraries are missing/hidden: - Control.Monad.State (and other chunks of the Control.Monad hierarchy, like Control.Monad.Error/Identity/List/Trans) - Test.HUnit (in fact Test.* is gone) and I'm sure there's plenty more missing. ? Alistair * Confidentiality Note: The information contained in this message, and any attachments, may contain confidential and/or privileged material. It is intended solely for the person(s) or entity to which it is addressed. Any review, retransmission, dissemination, or taking of any action in reliance upon this information by persons or entities other than the intended recipient(s) is prohibited. If you received this in error, please contact the sender and delete the material from any computer. * ___ 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] ANNOUNCE: Visual Haskell prerelease 0.2
Hi Shelarcy,
Could you check whether you have this registry key:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\VisualStudio\8.0\InstallDir
and tell me its value? Typically its value should be such that the
following script to work.
Set shell = CreateObject(WScript.Shell)
vstudioPath = shell.RegRead
(HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\VisualStudio\8.0\InstallDir)
shell.Run ( vstudioPath devenv.exe /Setup,0,true)
Cheers,
Krasimir
On 11/30/06, shelarcy [EMAIL PROTECTED] wrote:
Hi Krasimir,
On 11/30/06, shelarcy [EMAIL PROTECTED] wrote:
But ... I can't install Visual Haskell prerelease 0.2. Near
the end of install process, Microsoft Development Environment
cause error.
On Thu, 30 Nov 2006 17:03:22 +0900, Krasimir Angelov [EMAIL PROTECTED] wrote:
Could you tell me what error message you see during the installation?
If it is in Japan then translate it in English ;-).
It's not good error message. Anyway, I translate it.
Near the end of install process, error dialog opened and says:
---
The problem happende, so exit Microsoft Development Environment.
I'm sorry for causing inconvenience to you.
(under its message, error dialog has form that send error report
for Microsoft or shows error detail. These messages are not
important, so I don't translate that.)
---
And click form that shows error detail, another dialog opened.
It shows:
---
:Error ditail:
An unhandled exception has been caught by the VSW exception filter.
:Error Signature:
AppName: devenv.exe AppVer: 7.10.6030.0 ModName: unknown
ModVer: 0.0.0.0 Offset: 00bbbacc
:Report Detail:
(Below meassage attetion to user that error report send what.
So these messages are not important, too.)
---
Also it can help
if you run the installer with logging:
$ msiexec VSHaskell71.msi /l log.txt
msiexec doesn't run its command. And error dialog noticed that
you forgot /i optio. So I used below command.
$ msiexec /i VSHaskell71.msi /l log.txt
I think log.txt is much more useful than previous messages.
log.txt also has Japanese messages. So I translated that part.
---
(snip)
Action 20:38:17: CA_RegisterHelpFile.3643236F_FC70_11D3_A536_0090278A1BB8.
IHxRegisterSession::ContinueTransaction() returned 0.
Helpfile: C:\Program Files\Visual Haskell\doc\alex.HxS was successfully
registered to namespace vs_haskell.
elpfile: C:\Program Files\Visual Haskell\doc\building.HxS was successfully
registered to namespace vs_haskell.
Helpfile: C:\Program Files\Visual Haskell\doc\Cabal.HxS was successfully
registered to namespace vs_haskell.
Helpfile: C:\Program Files\Visual Haskell\doc\haddock.HxS was
successfully registered to namespace vs_haskell.
Helpfile: C:\Program Files\Visual Haskell\doc\happy.HxS was successfully
registered to namespace vs_haskell.
Helpfile: C:\Program Files\Visual Haskell\doc\libraries.HxS was
successfully registered to namespace vs_haskell.
Helpfile: C:\Program Files\Visual Haskell\doc\users_guide.HxS was
successfully registered to namespace vs_haskell.
Helpfile: C:\Program Files\Visual Haskell\doc\vh.HxS was successfully
registered to namespace vs_haskell.
Action 20:38:17: CA_RegisterPlugIn.3643236F_FC70_11D3_A536_0090278A1BB8.
IHxRegisterSession::ContinueTransaction() returned 0.
IHxPlugIn::RegisterHelpPlugIn() returned 0.
Namespace: vs_haskell was successfully plugged into namespace
MS.VSCC.2003.
Action 20:38:17: CA_CommitHelpTransaction.3643236F_FC70_11D3_A536_0090278A1BB8.
Action 20:38:17: RegisterProduct. Registering product
RegisterProduct: {FEC3263A-9034-49C5-8C5D-902231009894}
Action 20:38:18: PublishFeatures. Publishing Product Features
PublishFeatures: Feature: Complete
Action 20:38:18: PublishProduct. Publishing product information
1: {FEC3263A-9034-49C5-8C5D-902231009894}
Action 20:38:18: RollbackCleanup. Removing backup files
IHxRegisterSession::ContinueTransaction() returned 0.
Registration session: {FEC3263A-9034-49C5-8C5D-902231009894} was
successfully committed.
RollbackCleanup: File: C:\Config.Msi\fc3d12.rbf
RollbackCleanup: File: C:\Config.Msi\fc3d13.rbf
RollbackCleanup: File: C:\Config.Msi\fc3d14.rbf
RollbackCleanup: File: C:\Config.Msi\fc3d15.rbf
RollbackCleanup: File: C:\Config.Msi\fc3d16.rbf
Action ended 20:38:18: InstallFinalize. Return value 1.
Action 20:38:18: CA_HxMerge_VSCC.3643236F_FC70_11D3_A536_0090278A1BB8.
Action start 20:38:18: CA_HxMerge_VSCC.3643236F_FC70_11D3_A536_0090278A1BB8.
tion ended 20:40:09: CA_HxMerge_VSCC.3643236F_FC70_11D3_A536_0090278A1BB8.
Return value 1.
Action 20:40:09: CA_RemoveTempHxDs.3643236F_FC70_11D3_A536_0090278A1BB8.
Action start 20:40:09: CA_RemoveTempHxDs.3643236F_FC70_11D3_A536_0090278A1BB8.
Action ended 20:40:09: CA_RemoveTempHxDs.3643236F_FC70_11D3_A536_0090278A1BB8.
Return value 1.
Action 20:40:09: VSHaskellInstall. Register Visual Haskell Plugin
Action start 20:40:09: VSHaskellInstall.
Error 1720. There is a problem with this Windows Installer
[Haskell-cafe] Re: [Haskell] ANNOUNCE: Visual Haskell prerelease 0.2
You can try to setup it manually using the following commands:
$ regsvr32 /i:8.0 /n vs_haskell.dll
$ regsvr32 /i:8.0 /n vs_haskell_babel.dll
$ regsvr32 /i:8.0 /n vs_haskell_dlg.dll
$ devenv.exe /Setup
On 11/30/06, Krasimir Angelov [EMAIL PROTECTED] wrote:
Hi Shelarcy,
Could you check whether you have this registry key:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\VisualStudio\8.0\InstallDir
and tell me its value? Typically its value should be such that the
following script to work.
Set shell = CreateObject(WScript.Shell)
vstudioPath = shell.RegRead
(HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\VisualStudio\8.0\InstallDir)
shell.Run ( vstudioPath devenv.exe /Setup,0,true)
Cheers,
Krasimir
On 11/30/06, shelarcy [EMAIL PROTECTED] wrote:
Hi Krasimir,
On 11/30/06, shelarcy [EMAIL PROTECTED] wrote:
But ... I can't install Visual Haskell prerelease 0.2. Near
the end of install process, Microsoft Development Environment
cause error.
On Thu, 30 Nov 2006 17:03:22 +0900, Krasimir Angelov [EMAIL PROTECTED]
wrote:
Could you tell me what error message you see during the installation?
If it is in Japan then translate it in English ;-).
It's not good error message. Anyway, I translate it.
Near the end of install process, error dialog opened and says:
---
The problem happende, so exit Microsoft Development Environment.
I'm sorry for causing inconvenience to you.
(under its message, error dialog has form that send error report
for Microsoft or shows error detail. These messages are not
important, so I don't translate that.)
---
And click form that shows error detail, another dialog opened.
It shows:
---
:Error ditail:
An unhandled exception has been caught by the VSW exception filter.
:Error Signature:
AppName: devenv.exe AppVer: 7.10.6030.0 ModName: unknown
ModVer: 0.0.0.0 Offset: 00bbbacc
:Report Detail:
(Below meassage attetion to user that error report send what.
So these messages are not important, too.)
---
Also it can help
if you run the installer with logging:
$ msiexec VSHaskell71.msi /l log.txt
msiexec doesn't run its command. And error dialog noticed that
you forgot /i optio. So I used below command.
$ msiexec /i VSHaskell71.msi /l log.txt
I think log.txt is much more useful than previous messages.
log.txt also has Japanese messages. So I translated that part.
---
(snip)
Action 20:38:17: CA_RegisterHelpFile.3643236F_FC70_11D3_A536_0090278A1BB8.
IHxRegisterSession::ContinueTransaction() returned 0.
Helpfile: C:\Program Files\Visual Haskell\doc\alex.HxS was
successfully registered to namespace vs_haskell.
elpfile: C:\Program Files\Visual Haskell\doc\building.HxS was
successfully registered to namespace vs_haskell.
Helpfile: C:\Program Files\Visual Haskell\doc\Cabal.HxS was
successfully registered to namespace vs_haskell.
Helpfile: C:\Program Files\Visual Haskell\doc\haddock.HxS was
successfully registered to namespace vs_haskell.
Helpfile: C:\Program Files\Visual Haskell\doc\happy.HxS was
successfully registered to namespace vs_haskell.
Helpfile: C:\Program Files\Visual Haskell\doc\libraries.HxS was
successfully registered to namespace vs_haskell.
Helpfile: C:\Program Files\Visual Haskell\doc\users_guide.HxS was
successfully registered to namespace vs_haskell.
Helpfile: C:\Program Files\Visual Haskell\doc\vh.HxS was successfully
registered to namespace vs_haskell.
Action 20:38:17: CA_RegisterPlugIn.3643236F_FC70_11D3_A536_0090278A1BB8.
IHxRegisterSession::ContinueTransaction() returned 0.
IHxPlugIn::RegisterHelpPlugIn() returned 0.
Namespace: vs_haskell was successfully plugged into namespace
MS.VSCC.2003.
Action 20:38:17:
CA_CommitHelpTransaction.3643236F_FC70_11D3_A536_0090278A1BB8.
Action 20:38:17: RegisterProduct. Registering product
RegisterProduct: {FEC3263A-9034-49C5-8C5D-902231009894}
Action 20:38:18: PublishFeatures. Publishing Product Features
PublishFeatures: Feature: Complete
Action 20:38:18: PublishProduct. Publishing product information
1: {FEC3263A-9034-49C5-8C5D-902231009894}
Action 20:38:18: RollbackCleanup. Removing backup files
IHxRegisterSession::ContinueTransaction() returned 0.
Registration session: {FEC3263A-9034-49C5-8C5D-902231009894} was
successfully committed.
RollbackCleanup: File: C:\Config.Msi\fc3d12.rbf
RollbackCleanup: File: C:\Config.Msi\fc3d13.rbf
RollbackCleanup: File: C:\Config.Msi\fc3d14.rbf
RollbackCleanup: File: C:\Config.Msi\fc3d15.rbf
RollbackCleanup: File: C:\Config.Msi\fc3d16.rbf
Action ended 20:38:18: InstallFinalize. Return value 1.
Action 20:38:18: CA_HxMerge_VSCC.3643236F_FC70_11D3_A536_0090278A1BB8.
Action start 20:38:18: CA_HxMerge_VSCC.3643236F_FC70_11D3_A536_0090278A1BB8.
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Re: [Haskell-cafe] Re: [Haskell] ANNOUNCE: Visual Haskell prerelease 0.2
Hi Shelarcy, On 12/1/06, shelarcy [EMAIL PROTECTED] wrote: Why you always show 8.0 instead of 7.1? Sorry, I thought that you are using VStudio 2005. On Fri, 01 Dec 2006 03:48:49 +0900, Justin Bailey [EMAIL PROTECTED] wrote: I am having similar problems with the Visual Haskell install, and the commands given did not help. When I open Visual Studios Help | About dialog, I get an error about the package failing to initialize. I am installing to an English copy, however. Their commands didn't help for my environment too. I saw same error dialog that I sent previous mail. I saw this message this morning: http://www.cygwin.com/ml/cygwin/1998-04/msg00133.html I wonder whether this may cause the problem. I have uploaded a new vs_haskell.dll here: http://www.haskell.org/visualhaskell/vs_haskell.zip It is the same dll but without stripped debug symbols. Could you try to replace it in your installation? Cheers, Krasimir ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] [Haskell] Defining Cg, HLSL style vectors in Haskell
Hi Slavomir, On 11/28/06, Slavomir Kaslev [EMAIL PROTECTED] wrote: instance Num Float3 where . signum a | a == Float3 0 0 0 = 0 | otherwise = 1 signum has a natural generalization for vectors. signum v = vector with the same direction as v but with |v| = 1 where |v| is the absolute length of v. The problematic function in Num is abs. Ideally abs should be defined as: abs v = |v| but its type is Float3 - Float while the Num class requires Float3 - Float3. Cheers, Krasimir ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] [Haskell] Defining Cg, HLSL style vectors in Haskell
It is possible of course but your definition doesn't correspond to any operation in the usual vector algebra. By the way how do you define (*)? Isn't it 3D vector multiplication? Krasimir On 11/29/06, Slavomir Kaslev [EMAIL PROTECTED] wrote: You mean signum = normalize? What do you think of my comments here: After giving some thought on signum, I got to the point, that signum should be defined so that abs x * signum x = x holds. So it can be defined as signum (Vec2 x y) = Vec 2 (signum x) (signum y). It turns out that all the functions in Num, Floating, etc. classes can be given meaningful definitions for vectors in this pattern. That is f (Vecn x1 x2 .. xn) = Vecn (f x1) ... (f xn). And all expected laws just work. One can think of that like the way SIMD processor works, it does the same operations as on floats but on four floats at parallel. I think this is the way to define vector instances for Num, Floating, etc. For vector specific operations, such as normalize, len, dot, cross, etc. are declared in class Vector. -- Slavomir Kaslev ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] windows file locking
Hi Stefan, Haskell I/O systems implements single writer-multiple readers file locking. See http://www.haskell.org/ghc/docs/latest/html/libraries/base/System-IO.html#8 Cheers, Krasimir On 10/11/06, Stefan Aeschbacher [EMAIL PROTECTED] wrote: Hi I need to open a file and keep it open for writing (a log file). Another process has to read from this file. On windows the second process (e.g. tail -f) can not open the file. How can I open a file without this locking? regards Stefan ___ 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] How can I redirect stdout?
Hi Matthew, On Windows stdout/stderr/stdin exists only when your application is using the Console OS subsystem. All GUI applications doesn't have console window and they don't have stdout/stderr/stdin. When you are building DLLs then the subsystem is determined from the type of the application that is loading your DLL. In your particular case the DLL is loaded from Matlab which is definitely a GUI application. When you are trying to load the DLL from other C application then probably it is Console application and all print statements simply works. The solution that you can use is to replace all your print statements with Debug.Trace.trace or Debug.Trace.putTraceMsg. When you are using these functions from Console application then the output is redirected to stderr but when they are used from GUI application then the output goes to the debugger. You can see the output in the Debug pane in the Visual Studio IDE while you are running MatLab from the debugger. Cheers, Krasimir On 9/29/06, Matthew Bromberg [EMAIL PROTECTED] wrote: I'm reposting this in it's own new thread since I think it involves a general issue beyond exporting Haskell DLLs. I am having some problems with GHCs stdout when a Haskell program is called from a windows program. As I noted earlier I am calling some Haskell code from C as a bridge to being able to ultimately call Haskell from Matlab 6.5. The Haskell code is compiled into a .DLL file on a windows machine. Matlab calls some C code which then calls the Haskell code. As soon as it gets into the Haskell code I get this run time error in ghcDLL.dll stdout: hPutChars: invalid argument (Bad File Descriptor) The Haskell code seems to work correctly if called from a stand-alone C program. Moreover, if I scrub all print statements from the Haskell code, it appears to run correctly from Matlab. Matlab does not properly redirect stdout so any printf calls from the C code simply fail to print. However Haskell's behavior is to halt after generating a runtime error. The C code used to generate the Haskell .dll is of course mingw gcc, but the C code used to create my Matlab mex file is Microsoft VC++ 6.0. I tried to redirect stdout using freopen() in C, but that never seems to work with Microsoft. At any rate it certainly doesn't effect Haskells use of stdout. I think in general for windows programs there is no stdout defined, whereas it's always defined for console programs. My question is, is there some way I can redirect stdout from inside Haskell so that all output is sent to a file? Is there an equivalent of freopen() in Haskell that works? ___ 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] Greetings...
On 10/1/06, Seth Gordon [EMAIL PROTECTED] wrote: I'm planning to use HSQL, since it's in Debian stable and the API resembles what I'm already familiar with. Database access is slower than file access (which is one reason I want to move as much logic as I can out of SQL), so if the speed of getting rows out of the database turns out to be the bottleneck in my code, I'll either be happy that all the other code is so efficient or peeved that HSQL is so inefficient. Hi Seth, HSQL is just a thin wrapper around the underlying database engine. The performance in this case depends mainly on the database engine that you are using. Cheers, Krasimir ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Re: Greetings
On 10/1/06, Seth Gordon [EMAIL PROTECTED] wrote: Paul Johnson wrote: I've done some stuff with maybe 50k rows at a time. A few bits and pieces: 1: I've used HSQL (http://sourceforge.net/project/showfiles.php?group_id=65248) to talk to ODBC databases. Works fine, but possibly a bit slowly. I'm not sure where the delay is: it might just be the network I was running it over. One gotcha: the field function takes a field name, but its not random access. Access the fields in query order or it crashes. Thanks; that's certainly the sort of thing I like knowing in advance. This behaviour depends on the underlying database. I remember that MSSQL suffers from this disease. In addition with MSSQL you can't have more than one opened dataset for a given connection. MySQL and PostgreSQL doesn't have this problem. HSQL can't hide all differences between the possible backends. 2: For large data sets laziness is your friend. When reading files getContents presents an entire file as a list, but its really evaluated lazily. This is implemented using unsafeInterleaveIO. I've never used this, but in theory you should be able to set up a query that returns the entire database as a list and then step through it using lazy evaluation in the same way. I assume that the collectRows function in HSQL can produce this kind of a lazy list...right? No. collectRows collects all records eagerly. The problem with the lazy fetching is that you can close the database connection while your lazy data sets aren't fetched yet. It is getting worse if you can't have multiple opened data sets. If you still want lazy fetching you can write a custom function like collectRows but using unsafeInterleaveIO. Cheers, Krasimir ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Re: ANN: System.FilePath 0.9
On 7/26/06, Neil Mitchell [EMAIL PROTECTED] wrote: The main purpose of canoncialPath is to fix the case on Windows, so c:\my documents\file.doc becomes C:\My Documents\file.doc if that is the case correct version of the file. I think this function will not actually change the file with relation to the underying file system, so should be race free. (I will document more to make the operation clearer) Hi Neil, It seems like your canoncialPath function is already in the base package. Look at System.Directory.canonicalizePath. I have added it when I was working on the FilePath module for Cabal. The FilePath abstraction was discussed a number of times and it seems that people prefer an ADT representation instead of plain String. I tend to agree. Maybe such ADT based library can be integrated with some new IO library like the Streams library. Cheers, Krasimir ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Windows PowerShell Monad
Mostly coincidence. It isn't a good choice for name, I think but the same is true for .NET. Each time when I am googling for .NET I receive lots of irrelevant results. The same will happen with Monad now. On 7/14/06, Chad Scherrer [EMAIL PROTECTED] wrote: Yep, that's its codename. Now, I'm not much of a Windows person. Is the name just a weird coincidence, or does it have anything to do with monads as we know them? http://en.wikipedia.org/wiki/MSH_(shell) -- Chad Scherrer Time flies like an arrow; fruit flies like a banana -- Groucho Marx ___ 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] The History of Haskell
It was very interesting reading. Thanks! The slightly anecdotal style of writing is making it even pleasant to read. On 7/14/06, Simon Peyton-Jones [EMAIL PROTECTED] wrote: Friends, Phil Wadler, John Hughes, Paul Hudak and I have been writing a paper about the The History of Haskell We've submitted an earlier draft to the History Of Programming Languages conference (HOPL'07), and it's been accepted. We have to submit a more-or-less final draft by 1 September. This message is to invite you to read it, tell us what you think, and help us improve it. Here it is, along with a Wiki page for you to write comments: http://haskell.org/haskellwiki/History_of_Haskell Enjoy! Simon PS: If you followed a link earlier today, and have a version dated Feb, discard it. The one you want is dated July 14th. ___ 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] Haskell I/O inside: down the rabbit's hole
In the last section you said that IO has the same definition in GHC and Hugs. As far as I can remember in Hugs IO is defined as: newtype IO a = IO ((a - IOResult) - (IOError - IOResult) - IOResult) Of course this definition is builtin and cann't be seen in the Haskell source code. Cheers, Krasimir 2006/6/30, Bulat Ziganshin [EMAIL PROTECTED]: Hello Haskell, I'm just wrote exhaustive introduction to Haskell I/O titled HASKELL I/O INSIDE: DOWN THE RABBIT'S HOLE Can you please help me (and Haskell community) by proof-reading this text? Even if you will correct paragraph or two, it will advance the work further. Also feel free to add more explanations, correct me and ask (here) about new topics you need to be explained. The page is http://haskell.org/haskellwiki/IO_inside -- Best regards, Bulat mailto:[EMAIL PROTECTED] ___ 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] 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
Re: [Haskell-cafe] Progress on shootout entries
2006/1/3, Chris Kuklewicz [EMAIL PROTECTED]: And finially, the haskel entry for http://shootout.alioth.debian.org/benchmark.php?test=fannkuchlang=all is currently the *slowest* entry out of 28 languages. It is 813x slower than the c-code, 500x slower than OCaml. Should be easy to make it faster... In this particular case the flop function is very slow. flop :: Int8 - [Int8] - Int8 flop acc (1:xs) = acc flop acc list@(x:xs) = flop (acc+1) mangle where mangle = (reverse front) ++ back (front,back) = splitAt (fromIntegral x) list It can be optimized using a new mangle function: mangle :: Int - [a] - [a] mangle m xs = xs' where (rs,xs') = splitAt m xs rs splitAt :: Int - [a] - [a] - ([a], [a]) splitAt 0xs ys = (xs,ys) splitAt _[] ys = ([],ys) splitAt m (x:xs) ys = splitAt (m - 1) xs (x:ys) The mangle function transforms the list in one step while the original implementation is using reverse, (++) and splitAt. With this function the new flop is: flop :: Int8 - [Int8] - Int8 flop acc (1:xs) = acc flop acc list@(x:xs) = flop (acc+1) (mangle (fromIntegral x) list) ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Re: [Haskell] Making Haskell more open
2005/11/13, Gour [EMAIL PROTECTED]: Sven Panne ([EMAIL PROTECTED]) wrote: * DocBook XML can be transformed into a very rich collection of output formats: XHTML, HTML Help, DVI, PS, PDF, FO, plain text, etc. etc. txt2tags has the following backends: HTML, XHTML, SGML, LaTeX, Lout, man, Magic Point, Moin Moin, Page Maker 6.0 plain text. I don't see PDF and HtmlHelp backends here. Of course PDF can be created from LaTeX but this requires doble translation and you will need both txt2tags LaTeX installed. I spent some time to add support for HtmlHelp in haddock and I am using the HtmlHelp output from DocBook. I don't want to spend more time to learn a new markup and to make the things working with the new tools. I can't see real reasons to switch to new formats. Cheers, Krasimir ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] lockFile: fd out of range
2005/10/28, Joel Reymont [EMAIL PROTECTED]: Understood. I had the same problem with Erlang on Mac OSX and had to edit system files to bring it up to the maxium allowed of 10240. Worked like a charm after recompiling. What do you do on Windows where there's no hard-coded FD_SETSIZE? For quite a long time the file locking was broken on Windows and the files were not locked at all. After the last major GHC release the files are locked using the Win32 API and the lockFile hack isn't required. Cheers, Krasimir ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] FPS lib
2005/10/19, Simon Marlow [EMAIL PROTECTED]: On 19 October 2005 01:08, Donald Bruce Stewart wrote: Ah!! So what's going on on Linux, I wonder. Could it be something about 6.4.1? Are we seeing the difference between ForeignPtrs from 6.4 to 6.5? I will investigate. I bet that's the difference between ForeignPtrs in 6.4.1 and 6.5. I'm very tempted to merge the ForeignPtr optimisations into 6.4.2, so we can benefit from this earlier. The changes are all confined to one module (GHC/ForeignPtr.hs). I made my benchmarking with ghc-6.5 and I am getting relatively the same result as with ghc-6.4.1. I checked that the optimized ForeignPtr implementation is in my source tree. Any thoughts? Cheers, Krasimir ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] FPS lib
2005/10/19, Donald Bruce Stewart [EMAIL PROTECTED]: kr.angelov: Hello Guys, I tried my own version of PackedStrings and the results are very nice. It is entirely based on ByteArray# and Int#. I have made two tests: Elapsed time | | FastPackedString | PackedString | +-+--+--+ |test1| 99.26s |3.81s | |test2| 175.88s |5.28s | Maximum Memory Residency | | FastPackedString | PackedString | +-+--+--+ |test1| 40.60Mb | 36.25Mb | |test2| 91.58Mb | 33.94Mb | Wow. Now this is really surprising. Firstly, I would point out that only testing pack and concat may be slightly unrepresentative :) Of course the representative benchmark needs more test cases. However, on my machine: OpenBSD/Pentium-M 1.6G/ghc-6.5 -O Elapsed time:FPS Simon's PackedString Krasimir's test11.966s (40M) 2.151s (36M) 2.235s (36M) test26.048s (24M) 3.160s (73M) 2.318s (39M) Which is basically what I expected. Though perhaps I need to improve concat (we currently do things a little strangely in concat, due to the darcs legacy), but pack itself is nice and fast. Linux/Pentium 4 3.6G/ghc-6.4.1 -O test1 35.37s30.97s 2.180s test2 90.93s60.55s 1.916s Ah!! So what's going on on Linux, I wonder. Could it be something about 6.4.1? Are we seeing the difference between ForeignPtrs from 6.4 to 6.5? I will investigate. I wonder why the test results are so different. I made my benchmark on WinXP on Celeron 3GHz with GHC from CVS HEAD. Cheers, Krasimir ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] FPS lib
Hello Guys, I tried my own version of PackedStrings and the results are very nice. It is entirely based on ByteArray# and Int#. I have made two tests: --import StringUtils.PackedString as PS import Data.FastPackedString as PS main = test1 [] 100 --main = test2 [] 100 test1 xs 0 = return () test1 xs n = let x = PS.pack (* ++ show n ++ *) in x `seq` test1 (x : xs) (n-1) test2 xs 0 = return () test2 xs n = let x = PS.concat [PS.pack *, PS.pack (show n), PS.pack *] in x `seq` test2 (x : xs) (n-1) The detailed statistics are attached. Basically the results are: Elapsed time | | FastPackedString | PackedString | +-+--+--+ |test1| 99.26s |3.81s | |test2| 175.88s |5.28s | Maximum Memory Residency | | FastPackedString | PackedString | +-+--+--+ |test1| 40.60Mb | 36.25Mb | |test2| 91.58Mb | 33.94Mb | My PackedString implementation is attached too. Cheers, Krasimir test +RTS -stest1fs.stat 566,400,800 bytes allocated in the heap 8,394,100,944 bytes copied during GC (scavenged) 37,008 bytes copied during GC (not scavenged) 42,578,884 bytes maximum residency (7 sample(s)) 1042 collections in generation 0 ( 95.94s) 7 collections in generation 1 ( 0.46s) 84 Mb total memory in use INIT time0.03s ( 0.00s elapsed) MUT time2.83s ( 2.82s elapsed) GCtime 96.40s ( 96.34s elapsed) EXIT time0.00s ( 0.00s elapsed) Total time 99.26s ( 99.16s elapsed) %GC time 97.1% (97.2% elapsed) Alloc rate197,765,642 bytes per MUT second Productivity 2.9% of total user, 2.9% of total elapsed test +RTS -stest1ps.stat 552,632,612 bytes allocated in the heap 96,049,260 bytes copied during GC (scavenged) 82,350,516 bytes copied during GC (not scavenged) 38,016,248 bytes maximum residency (7 sample(s)) 1061 collections in generation 0 ( 0.66s) 7 collections in generation 1 ( 0.92s) 74 Mb total memory in use INIT time0.02s ( 0.00s elapsed) MUT time2.21s ( 2.20s elapsed) GCtime1.58s ( 1.47s elapsed) EXIT time0.00s ( 0.00s elapsed) Total time3.81s ( 3.67s elapsed) %GC time 41.5% (40.1% elapsed) Alloc rate247,484,376 bytes per MUT second Productivity 58.0% of total user, 60.2% of total elapsed test +RTS -stest2fs.stat 412,700,712 bytes allocated in the heap 6,411,611,864 bytes copied during GC (scavenged) 38,864 bytes copied during GC (not scavenged) 96,029,672 bytes maximum residency (8 sample(s)) 762 collections in generation 0 (169.31s) 8 collections in generation 1 ( 2.87s) 189 Mb total memory in use INIT time0.01s ( 0.00s elapsed) MUT time3.69s ( 3.58s elapsed) GCtime 172.18s (171.91s elapsed) EXIT time0.00s ( 0.00s elapsed) Total time 175.88s (175.49s elapsed) %GC time 97.9% (98.0% elapsed) Alloc rate111,450,367 bytes per MUT second Productivity 2.1% of total user, 2.1% of total elapsed test +RTS -stest2ps.stat 1,361,661,680 bytes allocated in the heap 93,647,172 bytes copied during GC (scavenged) 80,446,868 bytes copied during GC (not scavenged) 35,585,988 bytes maximum residency (7 sample(s)) 2616 collections in generation 0 ( 0.79s) 7 collections in generation 1 ( 0.83s) 69 Mb total memory in use INIT time0.02s ( 0.00s elapsed) MUT time3.64s ( 3.59s elapsed) GCtime1.62s ( 1.58s elapsed) EXIT time0.00s ( 0.00s elapsed) Total time5.28s ( 5.17s elapsed) %GC time 30.7% (30.6% elapsed) Alloc rate372,445,754 bytes per MUT second Productivity 68.9% of total user, 70.4% of total elapsed PackedString.hs Description: Binary data ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] FPS lib
I am curious why FPS is implemented on top of ForeignPtr. ByteArray# based implementation should be faster and more space efficient. Cheers, Krasimir 2005/10/18, Donald Bruce Stewart [EMAIL PROTECTED]: ekarttun: On 18.10 10:44, Bulat Ziganshin wrote: 2) as i say you before, i need to sort filenames in windows fashion (case-ignoring), so if you will include case-ignoring comparision operators - i will be glad Case ignoring comparisons make only sense on characters - not on bytes. And fps is ignoring character set conversion issues. I think the proper way is to provide a layer on top of (and separate from) fps that does conversion into character strings where things like case make sense. Indeed, SimonM's packed string code, which I'm currently integrating into FPS, is such a layer. -- Don ___ 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] FPS lib
ByteArray# can be passed to C functions as well. The only problem is with mmap which cann't be implemented with arrays. mmap returns a pointer to the mapped file which is outside the Haskell heap. Cheers, Krasimir 2005/10/18, Benjamin Franksen [EMAIL PROTECTED]: On Tuesday 18 October 2005 11:07, Krasimir Angelov wrote: I am curious why FPS is implemented on top of ForeignPtr. ByteArray# based implementation should be faster and more space efficient. I think the reason is C compatibility. A number of functions in FPS use ffi-bound C code (mmap, gz (de-)compression,...). Ben ___ 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] FPS lib
ForeignPtr requires more memory. Each ForeignPtr has ForeignPtrContents structure attached. In the ForeignPtrContents there is one IORef. Each finalizer adds one Weak# object in the heap. The IORef is a reference to a list of finalizers, so each new finalizer adds a new CONS cell. The finalizers require additional steps in GC time. I haven't tried to measure the difference between ForeignPtr and ByteArray# based implementations but it seems to me that the latter might be better. Of course it will be GHC specific. mmap is valuable only for large string. Typically only when someone wants to read the entire file in the memory. For this case a special data structure might be provided. Cheers, Krasimir ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] List of functions
2005/8/31, Sebastian Sylvan [EMAIL PROTECTED]: On 8/31/05, Dinh Tien Tuan Anh [EMAIL PROTECTED] wrote: Something like (untested)... xs - zipWith ($) forkIO (map (\f - f x y) funs) tids - sequence xs what does zipWith ($) do ? $ is function application, so zipWith ($) will zip a list of functions with a list of arguments, by applying the functions to the arguments pair-wise, producing a list of results. But forkIO is function not a list of functions. The above example is incorrect. I think it should be: tids - sequence [forkIO (f x y) | f - funs] Cheers, Krasimir ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Re: Oracle + Haskell advice?
2005/8/18, John Goerzen [EMAIL PROTECTED]: I would suspect that you could find Oracle drivers for either unixODBC, or some custom ODBC system that is nearly API-compatible. Once you have that, you have HSQL. I am planing to add support for Oracle in HSQL since now I am using it at office, but I will do that when I have enough time to hack with it. If there is any volunteer to do the job then I will be pretty happy to incorporate its work. Cheers, Krasimir ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Re: Visual Hashell Studio.NET 2005
Hi Maurício, VSHaskell has nothing to do with .NET or Mono. This isn't Haskell for .NET compiler. We are just developing programming environment for Haskell in Visual Studio. The environement uses the normal GHC compiler. Cheers, Krasimir On 6/6/05, Maurício [EMAIL PROTECTED] wrote: Brian Smith wrote: Hi, When will VHS support the Visual Studio.NET 2005 Beta? I'd like to volunteer to test VHS.NET 2005 when it is available. (Also, MS is giving away the VS.NET 2005 beta for free, and VS.NET 2003 costs a whopping $15.00 from my school's bookstore). Thanks, Brian Can we use Haskell with mono? [...], Maurício ___ 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] Visual Hashell Studio.NET 2005
Hi Brian, Currently I have only VS.NET 2003 license and this is my main development platform. I think it will not be much effort to upgrade VSHaskell to VS.NET 2005 but I have no way to try it. I may try to download Visual Studio.NET 2005 Beta but I am afraid that the download will be too large. Cheers, Krasimir On 6/5/05, Brian Smith [EMAIL PROTECTED] wrote: Hi, When will VHS support the Visual Studio.NET 2005 Beta? I'd like to volunteer to test VHS.NET 2005 when it is available. (Also, MS is giving away the VS.NET 2005 beta for free, and VS.NET 2003 costs a whopping $15.00 from my school's bookstore). Thanks, Brian ___ 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] G machine in FORTH
Actually I am very impressed from the FORTH simplicity and efficiency. I was developing one FORTH system for DOS a couple of years ago and I think it is very useful for small programs that have to perform low level/hardware tasks. Unfortunatelly it doesn't scale well for larger applications. I don't know how well it can be used as G-machine interpreter but its execution model has a lot of common with STG machine. In STG each closure has a header word which is a pointer to its entry code. In FORTH each procedure has a header word which also points to some entry code. The entry code receives the address of the entered procedure in special (usually EBX on x86) register just like in STG (where the used register is ESI). The execution of any FORTH program is a sequence of jumps from one entry code to another just like in STG. Of course STG is much more complicated because the closures are dynamically allocated and there is a garbage collector too. Thanks to its simple execution model I still think that FORTH is the fastest interpreted language, just like STG is the fastest virtual machine for Haskell. Cheers, Krasimir On 6/1/05, Andrew Harris [EMAIL PROTECTED] wrote: Hi - Brace yourself... I work in an environment where FORTH is still used. I've been thinking about writing a G-machine interpreter in FORTH so that one could write Haskell like programs that would compile down and run graph-reduction style on the FORTH machine. Many developers think FORTH is nice, but the language is so, shall we say, terse. I'm curious about what people think about this; having the expressiveness of a Haskell-like language that compiles to this environment might provide the best of both worlds, simple hardware architecture and an advanced programming language. let me know what you think, -andrew ___ 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: Type classes and definite types
Hi Bryn Keller, The solution for your problem is very simple. You just have to fetch all values as strings. In this way the library will do all required conversions for you. printRow stmt = do id - getFieldValue stmt ID code - getFieldValue stmt Code name - getFieldValue stmt Name putStrLn (unwords [id, code, name]) Cheers, Krasimir On 5/6/05, Bryn Keller [EMAIL PROTECTED] wrote: Max Vasin wrote: Bryn Keller [EMAIL PROTECTED] writes: Hi Max, Hello Bryn, Thanks for pointing this out. It's odd that I don't see that anywhere in the docs at the HToolkit site: http://htoolkit.sourceforge.net/doc/hsql/Database.HSQL.html but GHC certainly believes it exists. However, this doesn't actually solve the problem. Substituting toSqlValue for show in printRow' gives the same compile error: Main.hs:22:18: Ambiguous type variable `a' in the constraint: `SqlBind a' arising from use of `getFieldValue' at Main.hs:22:18-30 Probable fix: add a type signature that fixes these type variable(s) So, like with (show (read s)), we still can't use the function until we've established a definite type for the value, not just a type class. Yeah... Some more RTFSing shows that we have the getFieldValueType :: Statement - String - (SqlType, Bool) which allows us to write printRow stmt = do (id :: Int) - getFieldValue stmt ID let (codeType, _) = getFieldValueType stmt Code codestr - case codeType of SqlChar _ - do (c :: String) - getFieldValue stmt Code return (toSqlValue c) SqlInteger - do (i :: Int) - getFieldValue stmt Code return (toSqlValue i) -- etc for all SqlType data constructors putStrLn (unwords [show id, codestr]) At least it compiles. But it's ugly :-( Ah, good point! Ugly it may be, but at least it works. Thanks for the idea! Bryn ___ 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] Comparison with Clean?
If you want to compare Haskell and Clean then take a look at Object I/O library. It is ported to Haskell and you can learn a lot comparing both implementations. I spent a lot of time translating Clean functions to Haskell and my own impression is that Haskell's do notation is much more easier that uniqueness typing. In Clean you have to explicitly maintain the state while in Haskell it is hidden. In order to preserve uniquenes property of state, quite often you have write uggly functions like: getXYZ :: State - (XYZ, State) getXYZ st = (f st, st) while in Haskell the above function should be: getXYZ :: State - XYZ getXYZ st = f st It is more clean and from the type signature you can see that this is readonly access to the state. Cheers, Krasimir On 5/4/05, Daniel Carrera [EMAIL PROTECTED] wrote: Hi all, Anyone here familiar with the Clean programming language? http://www.cs.ru.nl/~clean/ It looks /very/ similar to Haskell, both in functionality and syntax. I would be grateful for any sort of comparison. I'm trying to decide which language I should try to learn. 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] File path programme
On Thu, 27 Jan 2005 16:31:21 -0500, robert dockins [EMAIL PROTECTED] wrote: I don't pretend to fully understand various unicode standard but it seems to me that these problems are deeper than file path library. The equation (decode . encode) /= id seems confusing for me. Can you give me an example when this happen? I am pretty sure that ISO 2022 encoded strings can have multiple ways to express the same unicode glyphs. This means that any sensible relation between IS0 2022 strings and unicode strings maps more than one ISO 2022 string onto the same unicode string. The inverse is therefore not a function. To make it a function one of the possibly several encodings of the unicode string will have to be chosen. So you have a ISO 2022 string A which is decoded to a unicode string U. We reencode U to an ISO 2022 string B. It may be that A /= B. That is the problem. The various UTF encodings do not have this particular problem; if a UTF string is valid, then it is a unique representation of a unicode string. However, decoding is still a partial function and can fail. A discussion about this problem floated around on this list several months ago. What can we do when the file name is passed as command line argument to program? We need to convert String to FilePath after all. Then we can parse the unicode and hope that nothing bad happens; the majority of the time, we will be OK. Or we can make the RTS allow access to the raw bytes of the program arguments, env variables, etc, and actually do the right thing. This means that all unicode languages, I have used before (Java,C#), are broken too. In this case I agree that special data type might be better. The development of the new FilePath should come together with the new unicode aware I/O library. I agree with David Roundy that the internal representation of FilePath should be compact as mush as posible. PackedString uses UArray Int Char to store strings and we can use UArray Int Word8 or even ByteArray#. Under Windows nearly all API functions have two versions: ANSI and Unicode (16-bit). Under WinNT+ each ANSI function is just a wrapper around its Unicode friend and the wrapper simply converts the passed strings. It was said that paths under Windows are [Word16] while in Posix they are [Word8]. This is true but in order to take advantages of this we need to use the native Windows API in the new I/O library. Another advantage of this is that in such way we can use the native non-blocking I/O under Windows. Cheers, Krasimir ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] File path programme
Hello Guys,
Let me propose another solution which is simpler (at least from my
point of view)and will not break the existing. When I designed the API
of the original System.FilePath library I looked at OS.Path modules
from Python and ML. They both uses plain string to keep the file path
but does precise parsing/printing of the path when it is manipulated.
I haven't ever heard of any language that uses special FilePath type
instead of plain string. I don't want to do any parsing/printing each
time when I need to open file or create directory. In most cases the
file path is passed as string from the outside world to the
application and if we have special FilePath then we need each time to
parse it. What I propose is the following:
- Keep the existing System.IO API the same. openFile, createDirectory
... will take the file path as string.
- Introduce two new modules System.Posix.FilePath and
System.Win32.FilePath. Each of them will provide functions for
parsing/printing of paths to/from some platform specific type:
PosixFilePath and Win32FilePath. As you can see from Robert Dockins
examples, these types can be completely different.
- Introduce third module System.FilePath which will do some basic
operations of path through parsing/printing. The API of this module
can be similar to this which I wrote but its implementation can be
more accurate if it works on some ADT instead of string. The module
will use #ifdef in order to import the right from the above two
modules.
In most cases we do only simple manipulations on path and I don't
think it is required and easy to explicitly parse/print the path only
in order to change its extension. I prefer to invoke changeFileExt and
don't care how the function will do its job. If someone would like to
perform any more complicated operations on file path he can import the
system specific module and use PosixFilePath or Win32FilePath. This is
basically the way in which OS.Path is implemented in ML.
The type class solution doesn't work very well. As Simon said it may
require to have #ifdef-s in some places in order to choice the right
type. Another disadvantage is that this will complicate some data
types. Example:
data FilePath a = MyFileInfo a = MyFileInfo { path :: a; size :: Integer }
I don't want to add extra type parameters here only in order to
specify the right FilePath type.
Cheers,
Krasimir
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Re: [Haskell-cafe] File path programme
I don't pretend to fully understand various unicode standard but it seems to me that these problems are deeper than file path library. The equation (decode . encode) /= id seems confusing for me. Can you give me an example when this happen? What can we do when the file name is passed as command line argument to program? We need to convert String to FilePath after all. Even simple manipulations break in the presence of encoding issues, or even just of unusual paths. What is the extension of \\.\TAPE0 ? Its not \TAPE0. BTW this is a valid path on Windows 2000 upwards. If you don't care about corner cases, then you have no worries. It would be nice to have correct handling for all valid paths on each supported OS though. Yes it isn't. If the library makes proper parsing it will return no extension. Krasimir ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] File path programme
Hello, Guys The System.FilePath might not be perfect and might not handle some unusual cases very well. Most of functions in this module are collected from Cabal/Alex/Happy/Haddock. Some of these tools already use their own functions for file path handling. Special care was taken to make them more portable but probably there is still enough room for optimizations. What about splitFileExt foo.bar.? (foo, bar.) or (foo.bar., )? The latter makes more sense to me, as an extension of the first case you give and splitting foo.tar.gz to (foo.tar, gz). I will take a look at this. I also don't know which case is more natural. (Win32) splitFileName server\\share == (server,share) (should probably be (server\\share,)) Why? server is the server name and share is the directory name on this server. splitFileName foo:xyz == (foo:.,xyz) (should be (.,foo:xyz) -- this refers to the named stream xyz of foo) System.FilePath currently doesn't support NTFS streams. I don't care much about them because they are rarely used but the things can be improved. The trouble here is that in some cases the drive letter cann't be easily distinguished. What does c:foo mean, file foo on drive c or stream foo of file c? joinPaths c:\\ \\foo == \\foo (should be c:\\foo. I realize that cd c:\\ on Windows doesn't actually make c:\\ the current directory, but ; doesn't separate shell commands either.) On Windows there is current drive and current directory on each drive. \\foo means top level directory foo on the current drive. If the current drive is c then I can agree that the joined path is c:\\foo but if the current drive is a then this is wrong. In both cases \\foo is the right answer. If you want something like c:\\foo you can use System.Directory.canonicalizePath. canonicalizePath \\foo returns either c:\\foo or a:\\foo. (Posix) splitFileName /foo == (/,foo), splitFileName /foo/ == (/foo,) (arguably makes sense, but why isn't it documented?) OK splitFileName /foo/bar == (/foo,bar) splitFileName /foo//bar == (/foo/,bar) (definitely a bug) Is /foo//bar valid file path and what does // mean? pathParents /foo///bar == [/,/foo,/foo,/foo,/foo/bar] Again what does /// mean? pathParents foo/../bar == [.,foo/../bar] (what if foo doesn't exist and we wanted to create it?) If foo doesn't exist then you can create it or raise an error Cheers, Krasimir ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Re: File path programme
On Tue, 25 Jan 2005 13:32:29 +0200, Krasimir Angelov [EMAIL PROTECTED] wrote: What about splitFileExt foo.bar.? (foo, bar.) or (foo.bar., )? The latter makes more sense to me, as an extension of the first case you give and splitting foo.tar.gz to (foo.tar, gz). I will take a look at this. I also don't know which case is more natural. (foo.bar., ) is more natural for me because it eleminates the special case for . and ... The original definition of splitFileExt is: splitFileExt :: FilePath - (String, String) splitFileExt p = case pre of [] - (p, []) (_:pre) - (reverse (pre++path), reverse suf) where (fname,path) = break isPathSeparator (reverse p) (suf,pre) | fname == . || fname == .. = (fname,) | otherwise = break (== '.') fname The definition can be changed to: splitFileExt :: FilePath - (String, String) splitFileExt p = case break (== '.') fname of (suf@(_:_),_:pre) - (reverse (pre++path), reverse suf) _ - (p, []) where (fname,path) = break isPathSeparator (reverse p) The letter is simplier, it doesn't treat . and .. as special cases and for it splitFileExt foo.bar. == (foo.bar., ) Cheers, Krasimir ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
