[Haskell-cafe] how to #include files within parsec ... without unsafePerformIO?
Hi Neil, Hi Daniel. Thank you for your help, using parsec 3.0.0 and liftIO was the solution. After installing new parsec I have had to use import Text.Parsec ... instead of ... import Text.ParserCombinators.Parsec ... to get it work. It seems Text.ParserCombinators.Parsec refers to old Parsec 2 Have a nice week--end, Leonard ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Creating a new Haskell mailing list
Am Donnerstag, 18. Juni 2009 16:21 schrieb Henning Thielemann: Ryan Trinkle schrieb: Hi all, I'm interested in starting a mailing list on haskell.org http://haskell.org. Who should I talk to about such things? Is it a mailing list related to a project? Then you may request a project on community.haskell.org, then you can start a mailing list at yourproj...@project.haskell.org See http://community.haskell.org/. Best wishes, Wolfgang ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Use MySQL from Haskell
Marciej, I went the HDBC route and got the same problem. Although it does not seem to be officially blessed, try installing the time-1.1.3 package. It's working for me at least, which I know is a dubious recommendation.What worked for me : 1) Install GHC 6.10.3 from the binary tarball 2) Intall the haskell platform. ( not without problems, sadly ) 3) cabal install HDBC-mysql voilà. That worked both on Kubuntu 9.04 and on Centos 5.3 On kubuntu it was a pain in the to figure out which files were needed for opengl. I had to make a symlink by hand. ( opengl was built by the haskell platform ) On centos 5.3 ... libedit was the problem, but once the haskell platform is installed, cabal install hdbc-mysql works like a charm. David. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Use MySQL from Haskell
Maciej Podgurski schrieb: So I switched to HDBC-2.1.1 and got the next compile error: Building convertible-1.0.5... Data/Convertible/Instances/Num.hs:671:0: warning: no newline at end of file [...] [5 of 8] Compiling Data.Convertible.Instances.C ( Data/Convertible/Instances/C.hs, dist\build/Data/C onvertible/Instances/C.o ) [6 of 8] Compiling Data.Convertible.Instances.Time ( Data/Convertible/Instances/Time.hs, dist\build/ Data/Convertible/Instances/Time.o ) Data/Convertible/Instances/Time.hs:64:0: Duplicate instance declarations: instance Typeable NominalDiffTime -- Defined at Data/Convertible/Instances/Time.hs:(64,0)-(65,42) instance Typeable NominalDiffTime -- Defined in time-1.1.3:Data.Time.Clock.UTC Data/Convertible/Instances/Time.hs:67:0: Duplicate instance declarations: instance Typeable UTCTime -- Defined at Data/Convertible/Instances/Time.hs:(67,0)-(68,34) instance Typeable UTCTime -- Defined in time-1.1.3:Data.Time.Clock.UTC Hi Maciej, this is quite easy to fix (although a little bit dirty). The problem is that time-1.1.3 now defines some Typeable instances which time-1.1.2.4 did not and which are therefore defined in convertible, too. I don't know a general fix to the problem, but you can either - download the convertible package and comment out the two instance declarations as shown in the error message and then cabal install it - install from Hackage with additional constraint: cabal install convertible --constraint=time1.1.3 I hope this will help you get HDBC running. Cheers, Björn ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Runtime strictness analysis for polymorphic HOFs?
Hi Max, I don't have anything in a public repository at this time. I have been exploring a series of designs in this space trying to see if any could be applied to a system like GHC's bytecode interpreter, but up to now I've been working mostly with cooperatively jitting x86-64 assembly to x86-64 assembly for a possibly commercial project. I have only recently started trying to adapt my research to a more functional setting. If you hop on #haskell some time, I'd be happy to talk further. -Edward Kmett On Thu, Jun 18, 2009 at 12:30 PM, Max Bolingbroke batterseapo...@hotmail.com wrote: 2009/6/18 Edward Kmett ekm...@gmail.com: What is interesting is in a lazy setting, if you are tracing a bytecode representation that knows about allocation and thunks, you can do some additional optimizations in here. If on every path to a side exit or the end of the loop you find that the thunk is evaluated you can evaluate it strictly and move its execution earlier in the trace. This gives you a weak form of runtime strictness analysis. If the pointer to that thunk never escapes, then you can unbox the contents of the thunk and operate on its members in registers. Add constant folding, polyinline caching to improve branch prediction for spineless tagless g-machine thunk evaluation, and code migration to the side exits and it becomes an interesting runtime system. This sounds absolutely awesome! Is the source code for your prototype publicly available anywhere? I'd love to take a look at the basic structure of something like this - trace JITing is something I keep meaning to look at in more depth. Cheers, Max ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] FFI question
Hello, I would like to write bindings from Haskell to Java. Is this possible? If so, where are examples? Vasili ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Re: Could someone give me a sample about haskelldb?
I changed it, some other problem occured. 1. How to compare a BoolT column to a True? t!c .. True could not work. 2. What shoud I use after !? Like table!col, recordset!col, what is col? Thanks. On Fri, Jun 19, 2009 at 1:24 PM, Magicloud Magicloudsmagicloud.magiclo...@gmail.com wrote: Hi, I am learning it following the very few documents on its site. Well, I failed, with the import modules, I still cannot compile it. The error is on T.*. 6 import Database.HaskellDB.HDBC.SQLite3 7 import Database.HaskellDB 8 import Database.HaskellDB.DBSpec 9 import Database.HaskellDB.DBSpec.PPHelpers 10 import Database.HaskellDB.Query 48 q = do 49 t - table $ Table notes [] 50 restrict ( t!T.done .. False ) 51 r - project ( T.subject t!T.subject ) 52 order [ desc r T.priority 53 , desc r T.dt ] 54 return r -- 竹密岂妨流水过 山高哪阻野云飞 -- 竹密岂妨流水过 山高哪阻野云飞 ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Re: Running a sub-process which dies with the main program
2009/6/18 Deniz Dogan deniz.a.m.do...@gmail.com: Hi I couldn't come up with a better subject than this one, so anyways... I have a small program which spawns a subprocess. However, when I hit C-c, the subprocess won't die, instead it will just keep running until it's done or until I kill it. I've looked around in System.Process for something suitable for my needs, but I can't seem to find it. Any ideas? With a tip from a person outside of the mailing list I found System.Process.system, which essentially does exactly what I was asking for. However, I would really like some more control over what file descriptors the subprocess should use (specifically stdout and stderr). Looking at the source code for System.Process.system, I find that it uses the syncProcess function, which would be useful to me, but isn't exported. So why is syncProcess not exported? Is there any good reason not to? -- Deniz Dogan ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Re: Running a sub-process which dies with the main program
Cum, 2009-06-19 tarihinde 11:58 +0200 saatinde, Deniz Dogan yazdı:
2009/6/18 Deniz Dogan deniz.a.m.do...@gmail.com:
Hi
I couldn't come up with a better subject than this one, so anyways...
I have a small program which spawns a subprocess. However, when I hit
C-c, the subprocess won't die, instead it will just keep running until
it's done or until I kill it. I've looked around in System.Process for
something suitable for my needs, but I can't seem to find it. Any
ideas?
With a tip from a person outside of the mailing list I found
System.Process.system, which essentially does exactly what I was
asking for.
Hey I'm already subscribed :) You can read from sout and serr with
below example. Hope that it helps.
module Main where
import System.Process -- using process-1.0.1.1
main = do
(_, sout, serr, p) - createProcess (proc sleep [10])
{ std_out = CreatePipe
, std_err = CreatePipe }
r - waitForProcess p
return ()
Regards,
--
aycan
___
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Re: [Haskell-cafe] Re: Running a sub-process which dies with the main program
2009/6/19 Aycan iRiCAN aycan.iri...@core.gen.tr:
Cum, 2009-06-19 tarihinde 11:58 +0200 saatinde, Deniz Dogan yazdı:
2009/6/18 Deniz Dogan deniz.a.m.do...@gmail.com:
Hi
I couldn't come up with a better subject than this one, so anyways...
I have a small program which spawns a subprocess. However, when I hit
C-c, the subprocess won't die, instead it will just keep running until
it's done or until I kill it. I've looked around in System.Process for
something suitable for my needs, but I can't seem to find it. Any
ideas?
With a tip from a person outside of the mailing list I found
System.Process.system, which essentially does exactly what I was
asking for.
Hey I'm already subscribed :) You can read from sout and serr with
below example. Hope that it helps.
module Main where
import System.Process -- using process-1.0.1.1
main = do
(_, sout, serr, p) - createProcess (proc sleep [10])
{ std_out = CreatePipe
, std_err = CreatePipe }
r - waitForProcess p
return ()
Thanks!
But this was the approach I used before I went to
System.Process.system and it did not work on my Linux machine. Looking
at the source code for system, we see that it uses syncProcess,
which has #ifdef mingw32_HOST_OS (IIRC) in which the code you gave me
resides. If mingw32_HOST_OS is not defined, one has to go through
quite a bit more trouble to get the same effect.
This is why it bugs me a bit that syncProcess is not exported. I can't
find any reason not to export it, but what do I know?
--
Deniz Dogan
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Re: [Haskell-cafe] Re: Running a sub-process which dies with the main program
Cum, 2009-06-19 tarihinde 12:42 +0200 saatinde, Deniz Dogan yazdı:
2009/6/19 Aycan iRiCAN aycan.iri...@core.gen.tr:
Cum, 2009-06-19 tarihinde 11:58 +0200 saatinde, Deniz Dogan yazdı:
2009/6/18 Deniz Dogan deniz.a.m.do...@gmail.com:
Hi
I couldn't come up with a better subject than this one, so anyways...
I have a small program which spawns a subprocess. However, when I hit
C-c, the subprocess won't die, instead it will just keep running until
it's done or until I kill it. I've looked around in System.Process for
something suitable for my needs, but I can't seem to find it. Any
ideas?
With a tip from a person outside of the mailing list I found
System.Process.system, which essentially does exactly what I was
asking for.
Hey I'm already subscribed :) You can read from sout and serr with
below example. Hope that it helps.
module Main where
import System.Process -- using process-1.0.1.1
main = do
(_, sout, serr, p) - createProcess (proc sleep [10])
{ std_out = CreatePipe
, std_err = CreatePipe }
r - waitForProcess p
return ()
Thanks!
But this was the approach I used before I went to
System.Process.system and it did not work on my Linux machine.
Give it a try. Try to send CTRL-C and look if sleep 10 (which is a
subprocess) process terminates.
ay...@aycan:~/haskell$ time ./deniz2 ps -ef | grep sleep
^C
real0m0.707s
user0m0.001s
sys 0m0.004s
aycan 13098 4430 0 13:50:23 pts/7 0:00 grep sleep
It terminates with ghc 6.10.3 on OpenSolaris.
Best Regards,
--
aycan
___
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Re: [Haskell-cafe] Re: Running a sub-process which dies with the main program
2009/6/19 Aycan iRiCAN aycan.iri...@core.gen.tr:
Cum, 2009-06-19 tarihinde 12:42 +0200 saatinde, Deniz Dogan yazdı:
2009/6/19 Aycan iRiCAN aycan.iri...@core.gen.tr:
Cum, 2009-06-19 tarihinde 11:58 +0200 saatinde, Deniz Dogan yazdı:
2009/6/18 Deniz Dogan deniz.a.m.do...@gmail.com:
Hi
I couldn't come up with a better subject than this one, so anyways...
I have a small program which spawns a subprocess. However, when I hit
C-c, the subprocess won't die, instead it will just keep running until
it's done or until I kill it. I've looked around in System.Process for
something suitable for my needs, but I can't seem to find it. Any
ideas?
With a tip from a person outside of the mailing list I found
System.Process.system, which essentially does exactly what I was
asking for.
Hey I'm already subscribed :) You can read from sout and serr with
below example. Hope that it helps.
module Main where
import System.Process -- using process-1.0.1.1
main = do
(_, sout, serr, p) - createProcess (proc sleep [10])
{ std_out = CreatePipe
, std_err = CreatePipe }
r - waitForProcess p
return ()
Thanks!
But this was the approach I used before I went to
System.Process.system and it did not work on my Linux machine.
Give it a try. Try to send CTRL-C and look if sleep 10 (which is a
subprocess) process terminates.
ay...@aycan:~/haskell$ time ./deniz2 ps -ef | grep sleep
^C
real 0m0.707s
user 0m0.001s
sys 0m0.004s
aycan 13098 4430 0 13:50:23 pts/7 0:00 grep sleep
It terminates with ghc 6.10.3 on OpenSolaris.
This is copied verbatim from my terminal. I used the exact some code
that you gave me.
% time ./test ps -ef | grep sleep
^C
real0m10.005s
user0m0.003s
sys 0m0.003s
deniz14095 14047 0 13:05 pts/100:00:00 grep sleep
What's strange though is that when I hit C-c *twice*, I get this behavior:
time ./test ps -ef | grep sleep
^C^C
real0m0.915s
user0m0.003s
sys 0m0.000s
This is with GHC 6.10.3 on Arch Linux i686.
--
Deniz Dogan
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[Haskell-cafe] Re: Could someone give me a sample about haskelldb?
Hi Magicloud, restrict (t!T.done .. constant False) should dot it but your t!T.done confuses me, is the the T.xxx due to an import? also the line 49 does not seem to be right. Would you mind to post your table and column definitions? Günther Magicloud Magiclouds schrieb: I changed it, some other problem occured. 1. How to compare a BoolT column to a True? t!c .. True could not work. 2. What shoud I use after !? Like table!col, recordset!col, what is col? Thanks. On Fri, Jun 19, 2009 at 1:24 PM, Magicloud Magicloudsmagicloud.magiclo...@gmail.com wrote: Hi, I am learning it following the very few documents on its site. Well, I failed, with the import modules, I still cannot compile it. The error is on T.*. 6 import Database.HaskellDB.HDBC.SQLite3 7 import Database.HaskellDB 8 import Database.HaskellDB.DBSpec 9 import Database.HaskellDB.DBSpec.PPHelpers 10 import Database.HaskellDB.Query 48 q = do 49 t - table $ Table notes [] 50 restrict ( t!T.done .. False ) 51 r - project ( T.subject t!T.subject ) 52 order [ desc r T.priority 53 , desc r T.dt ] 54 return r -- 竹密岂妨流水过 山高哪阻野云飞 ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Use MySQL from Haskell
The same with me - I'm on XP, and HDBC-odbc is the library I got running to access the MySQL database. Regards, Daniel Michael Snoyman schrieb: Marciej, I went the HDBC route and got the same problem. Although it does not seem to be officially blessed, try installing the time-1.1.3 package. It's working for me at least, which I know is a dubious recommendation. Also, I am currently using the hdbc-odbc package for accessing MySQL. I couldn't get hdbc-mysql to work properly. I hope that once I get this project working right, I'll have a chance to dig into the hdbc-mysql issue itself. Good luck! Michael On Fri, Jun 19, 2009 at 12:26 AM, Maciej Podgurski maciej.podgur...@googlemail.com mailto:maciej.podgur...@googlemail.com wrote: Hello, I'm trying to use MySQL from Haskell but it seems impossible for me to install one of the MySQL packages on my Windows XP machine. First I tired to install hsql-mysql-1.7.1 on GHC 6.10.3 but installing haskelldb-hsql failed with a hidden package error. So I added the old-time package to the cabal file but there still was a compile error (something due to the change from Exception to Exception e = e). So I switched to GHC 6.8.3 and tried it again. Now it says: Configuring hsql-mysql-1.7.1... Warning: 'extra-lib-dirs: /usr/lib/mysql' directory does not exist. Warning: 'include-dirs: /usr/include/mysql' directory does not exist. Warning: This package indirectly depends on multiple versions of the same package. This is highly likely to cause a compile failure. package process-1.0.0.1 requires filepath-1.1.0.0 package directory-1.0.0.1 requires filepath-1.1.0.0 package Cabal-1.6.0.3 requires filepath-1.1.0.2 Setup: Missing dependency on a foreign library: * Missing C library: mysqlclient This problem can usually be solved by installing the system package that provides this library (you may need the -dev version). If the library is already installed but in a non-standard location then you can use the flags --extra-include-dirs= and --extra-lib-dirs= to specify where it is. There's no Haskell package mysqlclient and I don't know how to install a C library in Haskell. So I switched to HDBC-2.1.1 and got the next compile error: Building convertible-1.0.5... Data/Convertible/Instances/Num.hs:671:0: warning: no newline at end of file [...] [5 of 8] Compiling Data.Convertible.Instances.C ( Data/Convertible/Instances/C.hs, dist\build/Data/C onvertible/Instances/C.o ) [6 of 8] Compiling Data.Convertible.Instances.Time ( Data/Convertible/Instances/Time.hs, dist\build/ Data/Convertible/Instances/Time.o ) Data/Convertible/Instances/Time.hs:64:0: Duplicate instance declarations: instance Typeable NominalDiffTime -- Defined at Data/Convertible/Instances/Time.hs:(64,0)-(65,42) instance Typeable NominalDiffTime -- Defined in time-1.1.3:Data.Time.Clock.UTC Data/Convertible/Instances/Time.hs:67:0: Duplicate instance declarations: instance Typeable UTCTime -- Defined at Data/Convertible/Instances/Time.hs:(67,0)-(68,34) instance Typeable UTCTime -- Defined in time-1.1.3:Data.Time.Clock.UTC So please help me, what GHC/package configuration will I need to use MySQL from my Haskell programs on Windows? I really like Haskell but all those broken packages are really discouraging. :( Best wishes, Maciej ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org mailto: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
[Haskell-cafe] Using Parsec with ByteString ?
Hi, May be it's a frequently asked question, but I have been unable to find my way in the parsec-3.0.0 library when trying to write a small parser with Parsec that could work with ByteStrings. I mean, there is the Text.Parsec.ByteString module which allows to parse a file using ByteStrings, but the parser one needs to write must parse ByteStrings instead of Strings (that is, something like having a Parsec Bytestring () type, unless I'm completely misunderstanding the situation). My problem is that I do not manage to write primitive parsing combinators (like string, satisfy, letter, etc.) to define my language's tokens. I'm surely missing some primitive somewhere (may be the Text.Parsec.Prim.token, though I do not really manage to use it). Thanks in advance, F. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Re: Running a sub-process which dies with the main program
Cum, 2009-06-19 tarihinde 13:09 +0200 saatinde, Deniz Dogan yazdı:
2009/6/19 Aycan iRiCAN aycan.iri...@core.gen.tr:
Cum, 2009-06-19 tarihinde 12:42 +0200 saatinde, Deniz Dogan yazdı:
2009/6/19 Aycan iRiCAN aycan.iri...@core.gen.tr:
Cum, 2009-06-19 tarihinde 11:58 +0200 saatinde, Deniz Dogan yazdı:
2009/6/18 Deniz Dogan deniz.a.m.do...@gmail.com:
Hi
I couldn't come up with a better subject than this one, so anyways...
I have a small program which spawns a subprocess. However, when I hit
C-c, the subprocess won't die, instead it will just keep running until
it's done or until I kill it. I've looked around in System.Process for
something suitable for my needs, but I can't seem to find it. Any
ideas?
With a tip from a person outside of the mailing list I found
System.Process.system, which essentially does exactly what I was
asking for.
Hey I'm already subscribed :) You can read from sout and serr with
below example. Hope that it helps.
module Main where
import System.Process -- using process-1.0.1.1
main = do
(_, sout, serr, p) - createProcess (proc sleep [10])
{ std_out = CreatePipe
, std_err = CreatePipe }
r - waitForProcess p
return ()
Thanks!
But this was the approach I used before I went to
System.Process.system and it did not work on my Linux machine.
Give it a try. Try to send CTRL-C and look if sleep 10 (which is a
subprocess) process terminates.
ay...@aycan:~/haskell$ time ./deniz2 ps -ef | grep sleep
^C
real0m0.707s
user0m0.001s
sys 0m0.004s
aycan 13098 4430 0 13:50:23 pts/7 0:00 grep sleep
It terminates with ghc 6.10.3 on OpenSolaris.
This is copied verbatim from my terminal. I used the exact some code
that you gave me.
% time ./test ps -ef | grep sleep
^C
real 0m10.005s
user 0m0.003s
sys 0m0.003s
deniz14095 14047 0 13:05 pts/100:00:00 grep sleep
What's strange though is that when I hit C-c *twice*, I get this behavior:
Hmm, I think GHC RTS handles SIGINT. I recompiled with thread support and got
the same behavour.
See: http://hackage.haskell.org/trac/ghc/wiki/Commentary/Rts/Signals
When the interrupt signal is received, the default behaviour of
the runtime is to attempt to shut down the Haskell program
gracefully. It does this by calling interruptStgRts() in
rts/Schedule.c (see Commentary/Rts/Scheduler#ShuttingDown). If a
second interrupt signal is received, then we terminate the
process immediately; this is just in case the normal shutdown
procedure failed or hung for some reason, the user is always
able to stop the process with two control-C keystrokes.
You better install signal handlers using installHandler.
Best Regards,
--
aycan
___
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Re: [Haskell-cafe] Re: Running a sub-process which dies with the main program
2009/6/19 Aycan iRiCAN aycan.iri...@core.gen.tr:
Cum, 2009-06-19 tarihinde 13:09 +0200 saatinde, Deniz Dogan yazdı:
2009/6/19 Aycan iRiCAN aycan.iri...@core.gen.tr:
Cum, 2009-06-19 tarihinde 12:42 +0200 saatinde, Deniz Dogan yazdı:
2009/6/19 Aycan iRiCAN aycan.iri...@core.gen.tr:
Cum, 2009-06-19 tarihinde 11:58 +0200 saatinde, Deniz Dogan yazdı:
2009/6/18 Deniz Dogan deniz.a.m.do...@gmail.com:
Hi
I couldn't come up with a better subject than this one, so anyways...
I have a small program which spawns a subprocess. However, when I hit
C-c, the subprocess won't die, instead it will just keep running
until
it's done or until I kill it. I've looked around in System.Process
for
something suitable for my needs, but I can't seem to find it. Any
ideas?
With a tip from a person outside of the mailing list I found
System.Process.system, which essentially does exactly what I was
asking for.
Hey I'm already subscribed :) You can read from sout and serr with
below example. Hope that it helps.
module Main where
import System.Process -- using process-1.0.1.1
main = do
(_, sout, serr, p) - createProcess (proc sleep [10])
{ std_out = CreatePipe
, std_err = CreatePipe }
r - waitForProcess p
return ()
Thanks!
But this was the approach I used before I went to
System.Process.system and it did not work on my Linux machine.
Give it a try. Try to send CTRL-C and look if sleep 10 (which is a
subprocess) process terminates.
ay...@aycan:~/haskell$ time ./deniz2 ps -ef | grep sleep
^C
real 0m0.707s
user 0m0.001s
sys 0m0.004s
aycan 13098 4430 0 13:50:23 pts/7 0:00 grep sleep
It terminates with ghc 6.10.3 on OpenSolaris.
This is copied verbatim from my terminal. I used the exact some code
that you gave me.
% time ./test ps -ef | grep sleep
^C
real 0m10.005s
user 0m0.003s
sys 0m0.003s
deniz 14095 14047 0 13:05 pts/1 00:00:00 grep sleep
What's strange though is that when I hit C-c *twice*, I get this behavior:
Hmm, I think GHC RTS handles SIGINT. I recompiled with thread support and got
the same behavour.
See: http://hackage.haskell.org/trac/ghc/wiki/Commentary/Rts/Signals
When the interrupt signal is received, the default behaviour of
the runtime is to attempt to shut down the Haskell program
gracefully. It does this by calling interruptStgRts() in
rts/Schedule.c (see Commentary/Rts/Scheduler#ShuttingDown). If a
second interrupt signal is received, then we terminate the
process immediately; this is just in case the normal shutdown
procedure failed or hung for some reason, the user is always
able to stop the process with two control-C keystrokes.
You better install signal handlers using installHandler.
Best Regards,
But that's what syncProcess does when mingw32_HOST_OS is not defined.
Also, compiling without -threaded doesn't help the problem on my
machine, it still acts the same.
--
Deniz Dogan
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[Haskell-cafe] duplicate definition for symbol
L.S., I am trying to run a program in GHCi, but I get a meesage that an object file is loaded twice; it appears that two different versions of package process are loaded, see the session text below. How can I solve this? GHCi, version 6.10.1: http://www.haskell.org/ghc/ :? for help Loading package ghc-prim ... linking ... done. Loading package integer ... linking ... done. Loading package base ... linking ... done. Prelude :load Main.lhs [1 of 1] Compiling Main ( Main.lhs, interpreted ) Ok, modules loaded: Main. *Main :main Loading package syb ... linking ... done. Loading package base-3.0.3.0 ... linking ... done. Loading package array-0.2.0.0 ... linking ... done. Loading package containers-0.2.0.0 ... linking ... done. Loading package bytestring-0.9.1.4 ... linking ... done. Loading package old-locale-1.0.0.1 ... linking ... done. Loading package old-time-1.0.0.1 ... linking ... done. Loading package filepath-1.1.0.1 ... linking ... done. Loading package Win32-2.2.0.0 ... linking ... done. Loading package directory-1.0.0.2 ... linking ... done. Loading package random-1.0.0.1 ... linking ... done. Loading package time-1.1.2.2 ... linking ... done. Loading package stm-2.1.1.2 ... linking ... done. Loading package split-0.1.1 ... linking ... done. Loading package HUnit-1.2.0.3 ... linking ... done. Loading package QuickCheck-1.2.0.0 ... linking ... done. Loading package process-1.0.1.1 ... linking ... done. Loading package haskell98 ... linking ... done. Loading package mtl-1.1.0.2 ... linking ... done. Loading package parsec-2.1.0.1 ... linking ... done. Loading package network-2.2.0.1 ... linking ... done. Loading package hslogger-1.0.7 ... linking ... done. Loading package process-1.0.1.0 ... GHCi runtime linker: fatal error: I found a duplicate definition for symbol _runInteractiveProcess whilst processing object file C:\Programs\ghc\ghc-6.10.1\process-1.0.1.0\HSprocess-1.0.1.0.o This could be caused by: * Loading two different object files which export the same symbol * Specifying the same object file twice on the GHCi command line * An incorrect `package.conf' entry, causing some object to be loaded twice. GHCi cannot safely continue in this situation. Exiting now. Sorry. -- Met vriendelijke groet, Henk-Jan van Tuyl -- http://functor.bamikanarie.com http://Van.Tuyl.eu/ -- ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] duplicate definition for symbol
Am Freitag 19 Juni 2009 16:06:50 schrieb Henk-Jan van Tuyl: L.S., I am trying to run a program in GHCi, but I get a meesage that an object file is loaded twice; it appears that two different versions of package process are loaded, see the session text below. How can I solve this? http://www.haskell.org/cabal/FAQ.html#dependencies-conflict Wow, that one is really common. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] ANNOUNCE fmlist
On Jun 18, 2009, at 9:57 AM, Sjoerd Visscher wrote: This is my first package on Hackage, so any comments are welcome! It is not only pleasingly elegant but also quite useful: Your Monad and MonadPlus instances lead me to an interesting observation. Various strategies for non-deterministic search can be implemented using FMList by expressing failure and choice via a Monoid instance. I have just finished a revision of a paper that explains how to factor two-continuation based backtracking (and other strategies) into a continuation monad transformer and a type class for non-deterministic computations (I'd be glad to receive comments!). http://www-ps.informatik.uni-kiel.de/~sebf/pub/atps09.html Now I recognise that one can also use FMList as the part that provides return and = and any Monoid for failure and choice. Especially, one can implement breadth-first search (bfs) using a monoid that collects levels of a search tree and iterative deepening depth-first search (idfs) using a monoid that represents depth-bounded computations. I have updated my package level-monad to use your library and monoids: http://hackage.haskell.org/package/level-monad The employed Monoid instances do not satisfy any monoid law. However, these are the simplest implementations of bfs and idfs that I am aware of, so I don't care very much ;) Sebastian -- Underestimating the novelty of the future is a time-honored tradition. (D.G.) ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] ANNOUNCE fmlist
On Jun 19, 2009, at 3:35 PM, Sjoerd Visscher wrote: transform t l = FM $ \f - unFM l (t f) Unfortunately I couldn't get this code to type-check, so the library doesn't use transform. With some help from Martijn van Steenbergen the type turned out to be: transform :: (forall b. Monoid b = (a - b) - (c - b)) - FMList c - FMList a I've updated the library to use the transform function. -- Sjoerd Visscher sjo...@w3future.com ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] packages on Hackage?
vigalchin: Hello, Haskell packages on Hackage can be hosted anywhere, yes? If a Haskell package is hosted on Hackage, how often is it backed up? Nightly. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] IORef memory leak
jsnow: I'm having some trouble with excessive memory use in a program that uses a lot of IORefs. I was able to write a much simpler program which exhibits the same sort of behavior. It appears that modifyIORef and writeIORef leak memory; perhaps they keep a reference to the old value. I tried both ghc-6.8.3 and ghc-6.10.1. Is this a known limitation, or is this a ghc bug, or am I using IORefs in the wrong way? -jim module Main where import Data.IORef import Control.Monad -- Leaks memory leakcheck1 ior = do go 10 where go 0 = return () go n = do modifyIORef ior (+1) go (n-1) It is not possible to write a modifyIORef that *doesn't* leak memory! -- Don ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] IORef memory leak
Don Stewart schrieb: It is not possible to write a modifyIORef that *doesn't* leak memory! Why? Or can one read about it somewhere? Best regards, Daniel ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] IORef memory leak
dvde:
Don Stewart schrieb:
It is not possible to write a modifyIORef that *doesn't* leak memory!
Why? Or can one read about it somewhere?
Try writing a version of this program, using modifyIORef only,
such that it doesn't exhaust the heap:
import Data.IORef
import Control.Monad
import System.IO.Unsafe
ref :: IORef Int
ref = unsafePerformIO $ newIORef 0
{-# NOINLINE ref #-}
main = do
modifyIORef ref (\a - a + 1)
main
Run it in a constrained environment, so you don't thrash:
$ ./A +RTS -M100M
Heap exhausted;
Current maximum heap size is 9744 bytes (95 MB);
use `+RTS -Msize' to increase it.
The goal is to run in constant space.
-- Don
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Re: [Haskell-cafe] IORef memory leak
It is not possible to write a modifyIORef that *doesn't* leak memory! Why? Or can one read about it somewhere? Possibly, Don meant that 'modifyIORef' is defined in a way that does not allow to enforce evaluation of the result of the modification function (a typical problem with fmap-style library functions): modifyIORef ref f = readIORef ref = writeIORef ref . f No matter whether 'f' is strict or not, the 'writeIORef r' doesn't evaluate its result, just stores the unevaluated application: r-newIORef 0 modifyIORef r (\x-trace done $ x+1) modifyIORef r (\x-trace done $ x+1) readIORef r done done 2 If it had been defined like this instead mRef r ($) f = readIORef r = (writeIORef r $) . f it would be possible to transform the strictness of 'writeIORef r' to match that of 'f': r-newIORef 0 mRef r ($) (\x-trace done $ x+1) mRef r ($) (\x-trace done $ x+1) readIORef r done done 2 r-newIORef 0 mRef r ($!) (\x-trace done $ x+1) done mRef r ($!) (\x-trace done $ x+1) done readIORef r 2 Claus ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Using Parsec with ByteString ?
On Fri, Jun 19, 2009 at 1:51 PM, Fernandquarantedeu...@yahoo.fr wrote: but the parser one needs to write must parse ByteStrings instead of Strings (that is, something like having a Parsec Bytestring () type, unless I'm completely misunderstanding the situation). My problem is that I do not manage to write primitive parsing combinators (like string, satisfy, letter, etc.) to define my language's tokens. Why would you want to do that ? After all, those combinators are already available in Text.Parsec.Char : they work on any Stream instance whose token type is Char, which happens to be the case for ByteString. -- Jedaï ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] IORef memory leak
Don Stewart schrieb:
dvde:
Don Stewart schrieb:
It is not possible to write a modifyIORef that *doesn't* leak memory!
Why? Or can one read about it somewhere?
Try writing a version of this program, using modifyIORef only,
such that it doesn't exhaust the heap:
import Data.IORef
import Control.Monad
import System.IO.Unsafe
ref :: IORef Int
ref = unsafePerformIO $ newIORef 0
{-# NOINLINE ref #-}
main = do
modifyIORef ref (\a - a + 1)
main
Run it in a constrained environment, so you don't thrash:
$ ./A +RTS -M100M
Heap exhausted;
Current maximum heap size is 9744 bytes (95 MB);
use `+RTS -Msize' to increase it.
The goal is to run in constant space.
-- Don
Hm, do you say it is not possible to write a modifyIORef function that
does not leak memory, or do you say it is not possible to use the
(existing) modifyIORef without having memory leaks?
I wrote the following which runs in constant space, but it introduces
strictness, which is not always desirable. And yes, using only
modifyIORef this could not be done this way, because the strict
evaluation happens on the IO-Monad-level. But such examples occured
already in this thread.
import Data.IORef
import Control.Monad
import System.IO.Unsafe
ref :: IORef Int
ref = unsafePerformIO $ newIORef 0
{-# NOINLINE ref #-}
main = do
myModifyIORef ref (\a - a + 1)
main
myModifyIORef :: IORef a - (a-a) - IO ()
myModifyIORef ref f = do
a - readIORef ref
let a' = f a
seq a' $ writeIORef ref a'
So would it make sense to create a strict modifyIORef' function?
best regards,
daniel
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Re: [Haskell-cafe] IORef memory leak
dvde:
Don Stewart schrieb:
dvde:
Don Stewart schrieb:
It is not possible to write a modifyIORef that *doesn't* leak memory!
Why? Or can one read about it somewhere?
Try writing a version of this program, using modifyIORef only, such
that it doesn't exhaust the heap:
import Data.IORef
import Control.Monad
import System.IO.Unsafe
ref :: IORef Int
ref = unsafePerformIO $ newIORef 0
{-# NOINLINE ref #-}
main = do
modifyIORef ref (\a - a + 1)
main
Run it in a constrained environment, so you don't thrash:
$ ./A +RTS -M100M
Heap exhausted;
Current maximum heap size is 9744 bytes (95 MB);
use `+RTS -Msize' to increase it.
The goal is to run in constant space.
-- Don
Hm, do you say it is not possible to write a modifyIORef function that
does not leak memory, or do you say it is not possible to use the
(existing) modifyIORef without having memory leaks?
The latter. atomicModifyIORef is harder though still, since it is a
primop with the same properties as modifyIORef :/
So would it make sense to create a strict modifyIORef' function?
Very much so. In fact, I'd argue the vast majority of uses are for the
WHNF-strict version.
-- Don
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Re: [Haskell-cafe] IORef memory leak
Yes I guessed that. Thanks, Daniel Claus Reinke schrieb: It is not possible to write a modifyIORef that *doesn't* leak memory! Why? Or can one read about it somewhere? Possibly, Don meant that 'modifyIORef' is defined in a way that does not allow to enforce evaluation of the result of the modification function (a typical problem with fmap-style library functions): modifyIORef ref f = readIORef ref = writeIORef ref . f No matter whether 'f' is strict or not, the 'writeIORef r' doesn't evaluate its result, just stores the unevaluated application: r-newIORef 0 modifyIORef r (\x-trace done $ x+1) modifyIORef r (\x-trace done $ x+1) readIORef r done done 2 If it had been defined like this instead mRef r ($) f = readIORef r = (writeIORef r $) . f it would be possible to transform the strictness of 'writeIORef r' to match that of 'f': r-newIORef 0 mRef r ($) (\x-trace done $ x+1) mRef r ($) (\x-trace done $ x+1) readIORef r done done 2 r-newIORef 0 mRef r ($!) (\x-trace done $ x+1) done mRef r ($!) (\x-trace done $ x+1) done readIORef r 2 Claus ___ 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] Use MySQL from Haskell
Maciej Podgurski wrote: Building convertible-1.0.5... There was unfortunately an API change in GHC 6.10.3 that could not be worked around. Either upgrade to 6.10.3 or use an older version of convertible. -- John ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] ANNOUNCE fmlist
On Jun 19, 2009, at 5:06 PM, Sebastian Fischer wrote: Your Monad and MonadPlus instances lead me to an interesting observation. Various strategies for non-deterministic search can be implemented using FMList by expressing failure and choice via a Monoid instance. I have just finished a revision of a paper that explains how to factor two-continuation based backtracking (and other strategies) into a continuation monad transformer and a type class for non- deterministic computations (I'd be glad to receive comments!). http://www-ps.informatik.uni-kiel.de/~sebf/pub/atps09.html Now I recognise that one can also use FMList as the part that provides return and = and any Monoid for failure and choice. Especially, one can implement breadth-first search (bfs) using a monoid that collects levels of a search tree and iterative deepening depth-first search (idfs) using a monoid that represents depth- bounded computations. I have updated my package level-monad to use your library and monoids: http://hackage.haskell.org/package/level-monad The employed Monoid instances do not satisfy any monoid law. However, these are the simplest implementations of bfs and idfs that I am aware of, so I don't care very much ;) Very nice. It is cool to see someone using this already! I see you did performance tests. How does your current version compare to f.e. one based on DiffLists? I wonder though, aren't you worried that updated versions of FMList might use the monoid laws to rewrite certains bits, and your code would break? Essentially you are using FMLists as a tree structure, which isn't possible when you abide by the monoid laws. I think you should be able to do the same thing in as many lines, using f.e. the ChoiceT type from MonadLib, where bfs and idfsBy are variations on runChoiceT. The ChoiceEff part might complicate things a bit though. But I might be missing some essential detail. greetings, -- Sjoerd Visscher sjo...@w3future.com ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] duplicate definition for symbol
Excerpts from Henk-Jan van Tuyl's message of Fri Jun 19 09:06:50 -0500 2009: L.S., I am trying to run a program in GHCi, but I get a meesage that an object file is loaded twice; it appears that two different versions of package process are loaded, see the session text below. How can I solve this? GHCi, version 6.10.1: http://www.haskell.org/ghc/ :? for help Loading package ghc-prim ... linking ... done. Loading package integer ... linking ... done. Loading package base ... linking ... done. Prelude :load Main.lhs [1 of 1] Compiling Main ( Main.lhs, interpreted ) Ok, modules loaded: Main. *Main :main Loading package syb ... linking ... done. Loading package base-3.0.3.0 ... linking ... done. Loading package array-0.2.0.0 ... linking ... done. Loading package containers-0.2.0.0 ... linking ... done. Loading package bytestring-0.9.1.4 ... linking ... done. Loading package old-locale-1.0.0.1 ... linking ... done. Loading package old-time-1.0.0.1 ... linking ... done. Loading package filepath-1.1.0.1 ... linking ... done. Loading package Win32-2.2.0.0 ... linking ... done. Loading package directory-1.0.0.2 ... linking ... done. Loading package random-1.0.0.1 ... linking ... done. Loading package time-1.1.2.2 ... linking ... done. Loading package stm-2.1.1.2 ... linking ... done. Loading package split-0.1.1 ... linking ... done. Loading package HUnit-1.2.0.3 ... linking ... done. Loading package QuickCheck-1.2.0.0 ... linking ... done. Loading package process-1.0.1.1 ... linking ... done. Loading package haskell98 ... linking ... done. Loading package mtl-1.1.0.2 ... linking ... done. Loading package parsec-2.1.0.1 ... linking ... done. Loading package network-2.2.0.1 ... linking ... done. Loading package hslogger-1.0.7 ... linking ... done. Loading package process-1.0.1.0 ... GHCi runtime linker: fatal error: I found a duplicate definition for symbol _runInteractiveProcess whilst processing object file C:\Programs\ghc\ghc-6.10.1\process-1.0.1.0\HSprocess-1.0.1.0.o This could be caused by: * Loading two different object files which export the same symbol * Specifying the same object file twice on the GHCi command line * An incorrect `package.conf' entry, causing some object to be loaded twice. GHCi cannot safely continue in this situation. Exiting now. Sorry. The easiest solution would simply be to 'ghc-pkg unregister process-1.0.1.1', and then rebuild all the packages that depend on it against process-1.0.1.0. The reason this is happening is simply because you have two libraries you depend on, each of which depends on a different version of process. It's a fairly annoying error, that is prone to happen when you have upgraded versions of GHC's bootlibs (i.e. necessary libraries for GHC installation.) Austin ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Use MySQL from Haskell
Does Database.HDBC.getTables work for you? I successfully created a new table and selected data from a database but getTables always returns an empty list (what is not a big problem since a query show tables works fine). Besh wishes, Maciej W dniu 19.06.2009 13:50 Daniel van den Eijkel pisze: The same with me - I'm on XP, and HDBC-odbc is the library I got running to access the MySQL database. Regards, Daniel Michael Snoyman schrieb: Marciej, I went the HDBC route and got the same problem. Although it does not seem to be officially blessed, try installing the time-1.1.3 package. It's working for me at least, which I know is a dubious recommendation. Also, I am currently using the hdbc-odbc package for accessing MySQL. I couldn't get hdbc-mysql to work properly. I hope that once I get this project working right, I'll have a chance to dig into the hdbc-mysql issue itself. Good luck! Michael ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] IORef memory leak
Don Stewart wrote:
dvde:
Don Stewart schrieb:
It is not possible to write a modifyIORef that *doesn't* leak memory!
Why? Or can one read about it somewhere?
Try writing a version of this program, using modifyIORef only,
such that it doesn't exhaust the heap:
import Data.IORef
import Control.Monad
import System.IO.Unsafe
ref :: IORef Int
ref = unsafePerformIO $ newIORef 0
{-# NOINLINE ref #-}
main = do
modifyIORef ref (\a - a + 1)
main
Run it in a constrained environment, so you don't thrash:
$ ./A +RTS -M100M
Heap exhausted;
Current maximum heap size is 9744 bytes (95 MB);
use `+RTS -Msize' to increase it.
The goal is to run in constant space.
-- Don
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Thanks, that's good to know.
do x - readIORef ior
writeIORef ior $! (x+1)
Works for me. The laziness of modifyIORef and workarounds would be a
good thing to have documented in the modifyIORef docs [1], since it's
probably a common source of memory leaks. I'd also be in favor of a
strict version of modifyIORef.
[1]
http://www.haskell.org/ghc/dist/current/docs/libraries/base/Data-IORef.html#v%3AmodifyIORef
-jim
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Re: [Haskell-cafe] Use MySQL from Haskell
Hi Björn,
thanks for your hint, I finally made HDBC-odbc and even hsql-mysql run.
Below is a step-by-step manual how to install both packages on windows
for people having the same troubles I had. I used GHC 6.8.3.
MySQL from HDBC-odbc
1.) Install package time-1.1.2.4.
2.) Download package convertible-1.0.5. In convertible.cabal find the line
Build-Depends: ..., time=1.1.2.4, ...
and replace it by
Build-Depends: ..., time=1.1.2.4 1.1.3, ...
Now the installation shouldn't fail with a compilation error.
3.) Download package HDBC-2.1.1, modfiy HDBC.cabal in the same way as in
2.) and install the package.
4.) Install package HDBC-odbc-2.1.0.0.
5.) There still was one thing I didn't know that made my example fail
with an exception. You need to install a MySQL ODBC connector for
Windows (available from dev.mysql.com).
6) Now the following example should return a list of all table names in
the database:
import Database.HDBC
import Database.HDBC.ODBC
main :: IO ()
main = do
conn - connectODBC DRIVER={MySQL ODBC 5.1 Driver};
SERVER=my_server; DATABASE=my_database; UID=my_username;
PASSWORD=my_password
qs - quickQuery' conn show tables []
mapM_ (\[SqlByteString table] - print table) qs
disconnect conn
(There's also a getTables function but it always returns an empty list
on my system, I don't know why).
MySQL from hsql-mysql
*
1.) Install package hsql-1.7.1.
2.) Download package hsql-mysql-1.7.1. In hsql-mysql.cabal find the line
include-dirs: Database/HSQL, /usr/include/mysql
and replace it by
include-dirs: Database/HSQL
Also find the line
extra-lib-dirs: /usr/lib/mysql
and remove it.
3.) Do a
runghc Setup configure --extra-include-dirs=path_to_mysql/include/
--extra-lib-dirs=path_to_mysql/lib/opt/
runghc Setup build
runghc Setup install
where path_to_mysql is the path to your MySQL server installation. I'm
using MySQL Server 5.1, so maybe you have to adjust the include or lib path.
4.) Now you should be able to compile:
import Database.HSQL
import Database.HSQL.MySQL
main :: IO ()
main = do
conn - connect my_server my_database my_username my_password
ts - tables conn
mapM_ print ts
disconnect conn
5.) Execute the main function. If you get an error like
Loading package hsql-mysql-1.7.1 ... can't load .so/.DLL for:
mysqlclient (addDLL: unknown error)
go to path_to_mysql/bin where a file libmySQL.dll should reside.
Copy this file to mysqlclient.dll and try executing the main function
again. Now you should get a list of all tables in the database.
Installing HDBC-mysql still failed due to a missing file mysql_config
which seems to be available only for linux systems.
Best wishes,
Maciej
W dniu 19.06.2009 09:31 Björn Peemöller pisze:
Maciej Podgurski schrieb:
So I switched to HDBC-2.1.1 and got the next compile error:
Building convertible-1.0.5...
Data/Convertible/Instances/Num.hs:671:0:
warning: no newline at end of file
[...]
[5 of 8] Compiling Data.Convertible.Instances.C (
Data/Convertible/Instances/C.hs, dist\build/Data/C
onvertible/Instances/C.o )
[6 of 8] Compiling Data.Convertible.Instances.Time (
Data/Convertible/Instances/Time.hs, dist\build/
Data/Convertible/Instances/Time.o )
Data/Convertible/Instances/Time.hs:64:0:
Duplicate instance declarations:
instance Typeable NominalDiffTime
-- Defined at Data/Convertible/Instances/Time.hs:(64,0)-(65,42)
instance Typeable NominalDiffTime
-- Defined in time-1.1.3:Data.Time.Clock.UTC
Data/Convertible/Instances/Time.hs:67:0:
Duplicate instance declarations:
instance Typeable UTCTime
-- Defined at Data/Convertible/Instances/Time.hs:(67,0)-(68,34)
instance Typeable UTCTime
-- Defined in time-1.1.3:Data.Time.Clock.UTC
Hi Maciej,
this is quite easy to fix (although a little bit dirty). The problem is
that time-1.1.3 now defines some Typeable instances which time-1.1.2.4
did not and which are therefore defined in convertible, too. I don't
know a general fix to the problem, but you can either
- download the convertible package and comment out the two instance
declarations as shown in the error message and then cabal install it
- install from Hackage with additional constraint: cabal install
convertible --constraint=time1.1.3
I hope this will help you get HDBC running.
Cheers,
Björn
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Re: [Haskell-cafe] IORef memory leak
Jim Snow js...@cs.pdx.edu writes: Works for me. The laziness of modifyIORef and workarounds would be a good thing to have documented in the modifyIORef docs, since it's probably a common source of memory leaks. I'd also be in favor of a strict version of modifyIORef. http://hackage.haskell.org/packages/archive/strict-io/0.1/doc/html/Data-IORef-Strict.html ? G. -- Gregory Collins g...@gregorycollins.net ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Installing agda through cabal
Hi all, I am trying to install agda through cabal but I get this: $ cabal install alex Resolving dependencies... [1 of 1] Compiling Main ( /tmp/alex-2.3.116333/alex-2.3.1/Setup.lhs, /tmp/alex-2.3.116333/alex-2.3.1/dist/setup/Main.o ) /tmp/alex-2.3.116333/alex-2.3.1/Setup.lhs:6:51: Warning: In the use of `buildVerbose' (imported from Distribution.Simple.Setup): Deprecated: Use buildVerbosity instead /tmp/alex-2.3.116333/alex-2.3.1/Setup.lhs:7:51: Warning: In the use of `defaultUserHooks' (imported from Distribution.Simple): Deprecated: Use simpleUserHooks or autoconfUserHooks, unless you need Cabal-1.2 compatibility in which case you must stick with defaultUserHooks Linking /tmp/alex-2.3.116333/alex-2.3.1/dist/setup/setup ... Warning: defaultUserHooks in Setup script is deprecated. Configuring alex-2.3.1... Preprocessing executables for alex-2.3.1... Building alex-2.3.1... [ 1 of 16] Compiling Set ( src/Set.hs, dist/build/alex/alex-tmp/Set.o ) [ 2 of 16] Compiling DFS ( src/DFS.hs, dist/build/alex/alex-tmp/DFS.o ) [ 3 of 16] Compiling Sort ( src/Sort.hs, dist/build/alex/alex-tmp/Sort.o ) [ 4 of 16] Compiling CharSet ( src/CharSet.hs, dist/build/alex/alex-tmp/CharSet.o ) [ 5 of 16] Compiling Map ( src/Map.hs, dist/build/alex/alex-tmp/Map.o ) [ 6 of 16] Compiling Paths_alex ( dist/build/autogen/Paths_alex.hs, dist/build/alex/alex-tmp/Paths_alex.o ) [ 7 of 16] Compiling Util ( src/Util.hs, dist/build/alex/alex-tmp/Util.o ) [ 8 of 16] Compiling AbsSyn ( src/AbsSyn.hs, dist/build/alex/alex-tmp/AbsSyn.o ) [ 9 of 16] Compiling ParseMonad ( src/ParseMonad.hs, dist/build/alex/alex-tmp/ParseMonad.o ) [10 of 16] Compiling Scan ( dist/build/alex/alex-tmp/Scan.hs, dist/build/alex/alex-tmp/Scan.o ) [11 of 16] Compiling Output ( src/Output.hs, dist/build/alex/alex-tmp/Output.o ) [12 of 16] Compiling Info ( src/Info.hs, dist/build/alex/alex-tmp/Info.o ) [13 of 16] Compiling NFA ( src/NFA.hs, dist/build/alex/alex-tmp/NFA.o ) [14 of 16] Compiling DFA ( src/DFA.hs, dist/build/alex/alex-tmp/DFA.o ) [15 of 16] Compiling Parser ( dist/build/alex/alex-tmp/Parser.hs, dist/build/alex/alex-tmp/Parser.o ) [16 of 16] Compiling Main ( src/Main.hs, dist/build/alex/alex-tmp/Main.o ) Linking dist/build/alex/alex ... Installing executable(s) in /home/pmatos/.cabal/bin pma...@drserver ~ $ cabal install agda Resolving dependencies... Configuring Agda-2.2.2... cabal: alex version =2.0.1 3 is required but it could not be found. cabal: Error: some packages failed to install: Agda-2.2.2 failed during the configure step. The exception was: exit: ExitFailure 1 As you can see, I had just finished installing alex 2.3.1, so why does cabal still request alex =2.0.1 3? Cheers, Paulo Matos ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Installing agda through cabal
Paulo J. Matos wrote: As you can see, I had just finished installing alex 2.3.1, so why does cabal still request alex =2.0.1 3? Probably you don't have alex in your PATH. - Jake ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Installing agda through cabal
On Fri, 2009-06-19 at 15:35 -0500, Jake McArthur wrote: Paulo J. Matos wrote: As you can see, I had just finished installing alex 2.3.1, so why does cabal still request alex =2.0.1 3? Probably you don't have alex in your PATH. - Jake Shouldn't cabal make sure the library it installs are in PATH? or at least, they are in the PATH of the apps built by cabal itself? Cheers, Paulo Matos ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Installing agda through cabal
On Fri, Jun 19, 2009 at 11:20 PM, Paulo J. Matospocma...@gmail.com wrote: Shouldn't cabal make sure the library it installs are in PATH? This would require modifying the path (since there may be no writable location on the existing path). But the PATH is set by a combination of several programs written in Turing-complete languages (shell script), and those programs themselves are in unknown locations (depending on the shell in use). or at least, they are in the PATH of the apps built by cabal itself? This is a possibility. But surely you're one day going to want to run your cabal-installed programs yourself (there are some pretty handy ones), so the easiest thing is to extend your path. It might be a good idea for cabal-install to warn that its bin directory is not in your path when you install an executable. --Max ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Installing agda through cabal
On Fri, 2009-06-19 at 23:35 +0200, Max Rabkin wrote: On Fri, Jun 19, 2009 at 11:20 PM, Paulo J. Matospocma...@gmail.com wrote: Shouldn't cabal make sure the library it installs are in PATH? This would require modifying the path (since there may be no writable location on the existing path). But the PATH is set by a combination of several programs written in Turing-complete languages (shell script), and those programs themselves are in unknown locations (depending on the shell in use). or at least, they are in the PATH of the apps built by cabal itself? This is a possibility. But surely you're one day going to want to run your cabal-installed programs yourself (there are some pretty handy ones), so the easiest thing is to extend your path. You're right. Added .cabal/bin to path and everything is ok. It might be a good idea for cabal-install to warn that its bin directory is not in your path when you install an executable. Yep, might be an interesting idea for warning. :) --Max ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Installing agda through cabal
Am Freitag 19 Juni 2009 23:41:05 schrieb Paulo J. Matos: It might be a good idea for cabal-install to warn that its bin directory is not in your path when you install an executable. Yep, might be an interesting idea for warning. :) This has been discussed in connection to the question where cabal should by default install things. IIRC, the plan is to have cabal display a message on first startup asking the user for the default install location [of binaries] and telling them to make sure it's in the path. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Use MySQL from Haskell
Hi Maciej, Database.HDBC.getTables works fine here (XP, ghc 6.10.2, HDBC-2.1.0, HDBC-ODBC-2.1.0.0) - it gives me the list of all tablenames, as intended. Which HDBC version do you use? best regards, daniel Maciej Podgurski schrieb: Does Database.HDBC.getTables work for you? I successfully created a new table and selected data from a database but getTables always returns an empty list (what is not a big problem since a query show tables works fine). Besh wishes, Maciej W dniu 19.06.2009 13:50 Daniel van den Eijkel pisze: The same with me - I'm on XP, and HDBC-odbc is the library I got running to access the MySQL database. Regards, Daniel Michael Snoyman schrieb: Marciej, I went the HDBC route and got the same problem. Although it does not seem to be officially blessed, try installing the time-1.1.3 package. It's working for me at least, which I know is a dubious recommendation. Also, I am currently using the hdbc-odbc package for accessing MySQL. I couldn't get hdbc-mysql to work properly. I hope that once I get this project working right, I'll have a chance to dig into the hdbc-mysql issue itself. Good luck! Michael ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Re: ANN: haskell-src-exts 1.0.0 rc1 (aka 0.5.2)
Hi all, Another day, another release candidate. Please see haskell-src-exts-0.5.5, 1.0.0 rc3. Thanks a lot to all reports, and please keep up the good work! Here we go again. Please have a look at haskell-src-exts-0.5.6, or 1.0.0 rc4. Thanks again for the reports, they're all truly invaluable. Changes in 0.5.6: === One major addition: * Support for relaxed layout in do-blocks! Yes, I caved in, after I got enough reports about it. Two stupid bugs fixed: * MagicHash ConId lexemes can now be followed by things other than space characters (like closing brackets: foo :: (Int#)). * ctypes (i.e. types with contexts and forall-quantifiers) can now appear inside tuples and lists if the proper extensions are on. Cheers, /Niklas ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Use MySQL from Haskell
Hi Daniel, I use HDBC-2.1.1 + HDBC-odbc-2.1.0.0 with GHC 6.8.3 and MySQL Server 5.1 on XP. The hsql equivalent Database.HSQL.tables works as expected. Best wishes, Maciej W dniu 20.06.2009 01:16 Daniel van den Eijkel pisze: Hi Maciej, Database.HDBC.getTables works fine here (XP, ghc 6.10.2, HDBC-2.1.0, HDBC-ODBC-2.1.0.0) - it gives me the list of all tablenames, as intended. Which HDBC version do you use? best regards, daniel Maciej Podgurski schrieb: Does Database.HDBC.getTables work for you? I successfully created a new table and selected data from a database but getTables always returns an empty list (what is not a big problem since a query show tables works fine). Besh wishes, Maciej ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] hs-dotnet users?
Hi all, I'm just touching base with Sigbjorns hs-dotnet package. Are there other users of this package out there who would like to share their experience? Günther ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Getting my mind around UArray - STUArray conversion
I'm trying to get my mind around how to thaw and then freeze a UArray. Theoretically, what I've written below should be a no-op, but I keep getting typing errors that I can't figure out. GHCI 6.10.3 says: Couldn't match expected type `UArray ix a' against inferred type `ST s (STUArray s ix1 e)' In the first argument of `(=)', namely `(unsafeThaw mem :: ST s (STUArray s ix e))' In the expression: (unsafeThaw mem :: ST s (STUArray s ix e)) = (\ mmem - unsafeFreeze mmem) In the definition of `wombat': wombat val idx mem = (unsafeThaw mem :: ST s (STUArray s ix e)) = (\ mmem - unsafeFreeze mmem) I'm figuring that usafeThaw with the type annotation should have given GHIC enough clue. Any suggestions? -scooter (WOMBAT = Waste Of Money Brains And Time) import Control.Monad; import Control.Monad.ST; import Data.Array.ST; import Data.Array.Unboxed; import Data.Array.MArray; import Data.Word; wombat :: (IArray UArray e, Ix ix, MArray (STUArray s) e (ST s)) = e - ix - UArray ix e - UArray ix e wombat val idx mem = (unsafeThaw mem :: ST s (STUArray s ix e)) = (\mmem - unsafeFreeze mmem) ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Getting my mind around UArray - STUArray conversion
On Friday 19 June 2009 9:43:29 pm Scott Michel wrote: wombat :: (IArray UArray e, Ix ix, MArray (STUArray s) e (ST s)) = e - ix - UArray ix e - UArray ix e wombat val idx mem = (unsafeThaw mem :: ST s (STUArray s ix e)) = (\mmem - unsafeFreeze mmem) Based on the error message and dealing with this sort of thing before, your problem is that when you say: :: ST s (STUArray s ix e) the s, ix and e there aren't the same as they are in the signature of wombat. To make them the same, you need the ScopedTypeVariables extension, and to make wombat's signature: wombat :: forall e ix s. ... where the dots are your current signature. It's possible you'll still have errors, but that will solve the one in your mail. -- Dan ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Getting my mind around UArray - STUArray conversion
Am Samstag 20 Juni 2009 03:51:08 schrieb Dan Doel: On Friday 19 June 2009 9:43:29 pm Scott Michel wrote: wombat :: (IArray UArray e, Ix ix, MArray (STUArray s) e (ST s)) = e - ix - UArray ix e - UArray ix e wombat val idx mem = (unsafeThaw mem :: ST s (STUArray s ix e)) = (\mmem - unsafeFreeze mmem) Based on the error message and dealing with this sort of thing before, your problem is that when you say: :: ST s (STUArray s ix e) the s, ix and e there aren't the same as they are in the signature of wombat. To make them the same, you need the ScopedTypeVariables extension, and to make wombat's signature: wombat :: forall e ix s. ... where the dots are your current signature. It's possible you'll still have errors, but that will solve the one in your mail. -- Dan No, only part of it. Another part is unsafeFreeze :: (Ix i, MArray a e m, IArray b e) = a i e - m (b i e) so unsafeThaw arr = unsafeFreeze lives in a monad, here (ST s) and to get the type he wants, he has to wrap it in runST. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Getting my mind around UArray - STUArray conversion
Oops, I replied too hastily. What I wrote in my first mail is a problem, as witnessed by the ix and ix1 in the error message. However, it isn't the main error. The main error is that you have a monadic expression, with type something like: ST s (UArray ix e) but the return type of your function is: UArray ix e To make a no-op you need to add a runST, something like: runST (unsafeThaw mem = unsafeFreeze) If you need to annotate 'unsafeThaw mem', that's where the ScopedTypeVariables will come in. However, there's also an issue that mentioning 's' in the type of wombat won't work with the runST, which may be a problem with the MArray constraint (and I'm not sure what to do about that off the top of my head; I've not worked with STUArray in a while, so you may be constructing an unresolvable ambiguity). Sorry for the confusion. -- Dan ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Confusion on the third monad law when using lambda abstractions
Hans van Thiel wrote:
On Wed, 2009-06-17 at 21:26 -0500, Jake McArthur wrote:
Jon Strait wrote:
I'm reading the third (bind associativity) law for monads in this form:
m = (\x - k x = h) = (m = k) = h
Arguably, that law would be better stated as:
(h = k) = m = h = (k = m)
This wouldn't be so unintuitive.
Hi,
The only place I've ever seen Kleisli composition, or its flip, used is
in demonstrating the monad laws. Yet it is so elegant and, even having
its own name, it must have some practical use. Do you, or anybody else,
have some pointers?
import Prelude hiding (mapM)
import Data.Traversable (mapM)
import Control.Monad((=))
newtype Fix f = Fix { unFix :: f (Fix f) }
cata phi = phi . fmap (cata phi) . unFix
cataM phiM = phiM = (mapM (cataM phiM) . unFix)
ana psi =Fix . fmap (ana psi). psi
anaM psiM = (liftM Fix . mapM (anaM psiM)) = psiM
etc. It's great for anyone who enjoys point-free style but wants to work
with monads.
--
Live well,
~wren
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