Re: [Haskell-cafe] Data.ByteString vs Data.ByteString.Lazy vs Data.ByteString.Char8
based on ghc-pkg list in my global ghc install I have bytestring-0.9.0.1 in my local ghc install I have bytestring-0.9.1.0 this difference of versions I strongly think is causing my problems.. When I run cabal install bytestring from the CLI, I get resolving differences If my assertion that the delta between the global vs local is causing my compile problems, then what should I do?? Regards, Vasili On Wed, Dec 3, 2008 at 1:52 AM, Galchin, Vasili [EMAIL PROTECTED] wrote: Warning: This package indirectly depends on multiple versions of the same package. This is highly likely to cause a compile failure. package binary-0.4.2 requires bytestring-0.9.0.1 package bio-0.3.4.1 requires bytestring-0.9.1.0 ah ha .. Ketil, this is what you are saying? If so, how do I fix? install a newer version of binary? regards, vasili On Wed, Dec 3, 2008 at 1:32 AM, Ketil Malde [EMAIL PROTECTED] wrote: Galchin, Vasili [EMAIL PROTECTED] writes: I think I am getting a namespace collition between Data.ByteString.Lazy.Char8.ByteString and Data.ByteString.Lazy.Internal.ByteString You rarely need to import 'Internal' directly. here is the error message Couldn't match expected type `B.ByteString' against inferred type `bytestring-0.9.0.1:Data.ByteString.Lazy.Internal.ByteString' Are you sure this is not just a versioning problem? I.e. that some library is built against bytestring-0.X.Y, but your current import is bytestring-0.A.B, but your program expects these to be the same? (And they probably are, but the compiler can't really tell). -k -- If I haven't seen further, it is by standing in the footprints of giants ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Data.ByteString vs Data.ByteString.Lazy vs Data.ByteString.Char8
Galchin, Vasili [EMAIL PROTECTED] writes: Warning: This package indirectly depends on multiple versions of the same package. This is highly likely to cause a compile failure. package binary-0.4.2 requires bytestring-0.9.0.1 package bio-0.3.4.1 requires bytestring-0.9.1.0 ah ha .. Ketil, this is what you are saying? Yes, exactly. If so, how do I fix? install a newer version of binary? Just recompiling it against bytestring-0.9.1.0 would suffice. You really should anyway, bytestring-0.9.0.1 has a nasty performance issue. -k -- If I haven't seen further, it is by standing in the footprints of giants ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Re: Fun with type functions
Simon Peyton-Jones wrote:
can you tell us about the most persuasive, fun application
you've encountered, for type families or functional dependencies?
I'm using them to provide witnesses to lenses.
Given two lenses on the same base type, I want to compare them, and if
they're the same lens, know that they have the same view type.
data Lens base view = MkLens
{
-- lensWitness :: ???,
lensGet :: base - view,
lensPut :: base - view - base
};
How do I compare Lens base view1 and Lens base view2, and match up
view1 and view2?
The difficulty is that my witnesses are monomorphic, while a lens may be
polymorphic. For instance, the lens corresponding to the fst function:
fstLens :: Lens (a,b) a;
fstLens = MkLens
{
lensGet = fst,
lensPut = \(_,b) a - (a,b)
};
I only want to generate one open witness for fstLens, but what is its type?
This is where type functions come in. I have a type family TF, and a
basic set of instances:
type family TF tf x;
data TFIdentity;
type instance TF TFIdentity x = x;
data TFConst a;
type instance TF (TFConst a) x = a;
data TFApply (f :: * - *);
type instance TF (TFApply f) x = f x;
data TFMatch;
type instance TF TFMatch (f a) = a;
data TFMatch1;
type instance TF TFMatch1 (f a b) = a;
data TFCompose tf1 tf2;
type instance TF (TFCompose tf1 tf2) x = TF tf1 (TF tf2 x);
I create a new witness type, that witnesses type functions:
import Data.Witness;
data TFWitness w x y where
{
MkTFWitness :: w tf - TFWitness w x (TF tf x);
};
instance (SimpleWitness w) = SimpleWitness (TFWitness w x) where
{
matchWitness (MkTFWitness wtf1) (MkTFWitness wtf2) = do
{
MkEqualType - matchWitness wtf1 wtf2;
return MkEqualType;
};
};
So for my lens type, I want a witness for the type function from base to
view:
data Lens base view = MkLens
{
lensWitness :: TFWitness IOWitness base view,
lensGet :: base - view,
lensPut :: base - view - base
};
For our fst lens, I can now generate a witness for the function from
(a,b) to a.
fstWitness :: IOWitness TFMatch1;
fstWitness - newIOWitness; -- language extension
fstLens :: Lens (a,b) a;
fstLens = MkLens
{
lensWitness = MkTFWitness fstWitness,
lensGet = fst,
lensPut = \(_,b) a - (a,b)
};
I can now compare two lenses like this:
get1put2 :: Lens base view1 - Lens base view2 - base - Maybe base;
get1put2 lens1 lens2 b = do
{
MkEqualType - matchWitness (lensWitness lens1) (lensWitness lens2);
return (lensPut lens2 b (lensGet lens1 b));
};
(Actually, I'm doing something a bit more useful than get1put2.)
--
Ashley Yakeley
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Re: [Haskell-cafe] What causes loop?
Martin Hofmann wrote: I've already posted this mail on haskell-cafe, but apparently the subject suggested a too simple question, so I try it here again. I am picking up a discussion with the same topic from haskell-users on 8th November. Note that you have been sending to haskell-cafe again. Your recipient name says haskell-beginners, but the address is haskell-cafe. Anyway, loop really means a loop in evalutation order, not some statebased deadlock (see below). Thunks with reference on themselves was mentioned as main reason for loop. A safe recursive definition would be let x = Foo (x+1) However, if you leave out the constructor, let x = x + 1 you get a loop (or a deadlock). Are there any other reasons? I am trying to debug monadic code which stores state information in a record maintaining several Data.Maps, but in vain so far. A state is modified/changed in several steps by a compound function i.e. changeA $ changeB $ changeC state Could this also lead to a deadlock? I don't think so. At least not in a way that leads to loop. If you get loop then you really have some infinite recursion in your program. Maybe you can track it down with Debug.Trace.trace. If so, can I prevent this using CPS? -- Dr. Janis Voigtlaender http://wwwtcs.inf.tu-dresden.de/~voigt/ mailto:[EMAIL PROTECTED] ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] What causes loop?
Janis Voigtlaender wrote: Martin Hofmann wrote: I've already posted this mail on haskell-cafe, but apparently the subject suggested a too simple question, so I try it here again. I am picking up a discussion with the same topic from haskell-users on 8th November. Note that you have been sending to haskell-cafe again. Your recipient name says haskell-beginners, but the address is haskell-cafe. Anyway, loop really means a loop in evalutation order, not some statebased deadlock (see below). Thunks with reference on themselves was mentioned as main reason for loop. A safe recursive definition would be let x = Foo (x+1) However, if you leave out the constructor, let x = x + 1 you get a loop (or a deadlock). Are there any other reasons? I am trying to debug monadic code which stores state information in a record maintaining several Data.Maps, but in vain so far. A state is modified/changed in several steps by a compound function i.e. changeA $ changeB $ changeC state Could this also lead to a deadlock? I don't think so. At least not in a way that leads to loop. If you get loop then you really have some infinite recursion in your program. Maybe you can track it down with Debug.Trace.trace. If so, can I prevent this using CPS? Oh, that last question was from the original mail, not from my answer. In any case, I don't think that CPS will help in finding the looping error in your program. -- Dr. Janis Voigtlaender http://wwwtcs.inf.tu-dresden.de/~voigt/ mailto:[EMAIL PROTECTED] ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Re: ANNOUNCE: gitit 0.2 release - wiki using HAppS, git, pandoc
Good morning, I wonder if it is possible to embed regular HTML code inside gitit (on 0.3.2) pages, such as java applets like the following. APPLET CODE = GHood.class ARCHIVE = GHood.jar WIDTH = 1100 HEIGHT = 400 ALT = you should see an instance of GHood here, as an applet PARAM NAME = eventSource VALUE =factHylo.log PARAM NAME = delay VALUE =150 PARAM NAME = scale VALUE =75 /APPLET I am assuming that as a wiki, it is only possible to point to external pages. Thanks, hugo On Sun, Nov 9, 2008 at 10:01 PM, Chris Eidhof [EMAIL PROTECTED] wrote: If anyone else has problems installing gitit, try updating your cabal-install (and cabal). I had old versions on my computer, and updating them solved my gitit build-problems. -chris On 9 nov 2008, at 22:41, John MacFarlane wrote: I've just uploaded a new version (0.2.1) that requires HAppS = 0.9.3 0.9.4. (There are small API changes from 0.9.2 to 0.9.3, so I thought it best not to allow 0.9.2.x, even though it still compiles with a warning.) +++ Hugo Pacheco [Nov 09 08 20:41 ]: a new HAppS version [1]0.9.3.1 has been released, and gitit requires HApps==[2]0.9.2.1. should ti be ok just to relax the dependency? On Sat, Nov 8, 2008 at 8:32 PM, John MacFarlane [EMAIL PROTECTED] wrote: I've uploaded an early version of gitit, a Haskell wiki program, to HackageDB. Gitit uses HAppS as a webserver, git for file storage, pandoc for rendering the (markdown) pages, and highlighting-kate for highlighted source code. Some nice features of gitit: - Pages and uploaded files are stored in a git repository and may be added, deleted, and modified directly using git. - Pages may be organized into subdirectories. - Pandoc's extended version of markdown is used, so you can do tables, footnotes, syntax-highlighted code blocks, and LaTeX math. (And you can you pandoc to convert pages into many other formats.) - Math is rendered using jsMath (which must be installed separately). - Source code files in the repository are automatically rendered with syntax highlighting (plain/text version is also available). You can check it out on my webserver: [4] http://johnmacfarlane.net:5001/ Or try it locally: cabal update cabal install pandoc -fhighlighting cabal install gitit gitit # note: this will create two subdirectories in the working directory # then browse to [5]http://localhost:5001. There's a git repository at [6] http://github.com/jgm/gitit/tree/master. Comments and patches are welcome. John ___ Haskell-Cafe mailing list [EMAIL PROTECTED] [8]http://www.haskell.org/mailman/listinfo/haskell-cafe -- [9]www.di.uminho.pt/~hpacheco References Visible links 1. http://0.9.3.1/ 2. http://0.9.2.1/ 3. mailto:[EMAIL PROTECTED] 4. http://johnmacfarlane.net:5001/ 5. http://localhost:5001/ 6. http://github.com/jgm/gitit/tree/master 7. mailto:Haskell-Cafe@haskell.org 8. http://www.haskell.org/mailman/listinfo/haskell-cafe 9. http://www.di.uminho.pt/~hpacheco ___ 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 -- www.di.uminho.pt/~hpacheco ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Cabal and Hat?
Is it possible to use cabal to build the files that hat would need to do tracing (i.e. .htx files)? /M -- Magnus Therning(OpenPGP: 0xAB4DFBA4) magnus＠therning．org Jabber: magnus＠therning．org http://therning.org/magnus identi.ca|twitter: magthe ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Re: What causes loop?
Martin Hofmann wrote: Thunks with reference on themselves was mentioned as main reason for loop. A safe recursive definition would be let x = Foo (x+1) However, if you leave out the constructor, let x = x + 1 you get a loop (or a deadlock). Are there any other reasons? A program that exits with loop is basically a program that runs forever. Examples of programs that run forever are let x = x + 1 in x let f x = f x in f 1 In special cases, the run-time system is able to detect that the program would run forever, and exits with loop if that happens. Sorry, a lot of questions at once, but I am kind of helpless because I can't find any reason of my loop, so any comments, experience, and tips are highly appreciated. Sometimes, a simple cause is accidentally using the same variable name, i.e. writing let (c,s) = foobar s in ... while you meant let (c,s') = foobar s in ... At other times, non-termination is caused by not using enough irrefutable patterns. But this usually only happens when writing algorithms that heavily exploit recursion and laziness, which probably doesn't apply to your case. You may want to try the new GHCi debugger, maybe it helps finding the loop. Regards, H. Apfelmus ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Re: What causes loop?
I was not sure about it, so I just speculated. Anyway, thanks a lot. martin ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Data.ByteString vs Data.ByteString.Lazy vs Data.ByteString.Char8
On Wed, 2008-12-03 at 01:52 -0600, Galchin, Vasili wrote: Warning: This package indirectly depends on multiple versions of the same package. This is highly likely to cause a compile failure. package binary-0.4.2 requires bytestring-0.9.0.1 package bio-0.3.4.1 requires bytestring-0.9.1.0 ah ha .. Ketil, this is what you are saying? If so, how do I fix? install a newer version of binary? This is the most significant issue that cabal-install addresses. It works out what needs to be rebuilt to get consistent dependencies. In this example you could run: $ cabal install --dry-run in the directory containing your package and it will say what it would install or re-install to be able to build your package. If you drop the --dry-run then it will actually do it, including installing your package. Duncan ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] ByteString web site papers
On Tue, 2008-12-02 at 22:56 -0600, Galchin, Vasili wrote: Hello, http://www.cse.unsw.edu.au/~dons/fps.html Are the papers/slides still up-to-date for someone to get up-to-speed on ByteString motivation and implementation? Yes. Anything more recent? It links to the stream fusion paper but that's more about lists than bytestrings. Duncan ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Cabal and Hat?
On Wed, 2008-12-03 at 09:36 +, Magnus Therning wrote: Is it possible to use cabal to build the files that hat would need to do tracing (i.e. .htx files)? No, but if you'd like to add support that'd be a great service to everyone. Duncan ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Problem building HXQ on Mac OS 10.5.5
Hi, Am 03.12.2008 um 02:00 schrieb Gwern Branwen: I haven't looked at the source, so take this as off-the-cuff: try importing not Control.Exception but Control.OldException. changing Control.Exceptionto Control.OldException didn't work. But changing SomeException to Exception seems to solve the problem (see below). At least I can now built it and use xquery. I think these days I get more in to it and understand what I was doing. ;-) Could it be a problem with the version of GHC? I'm using 6.10.1. Is SomeException still supported? At the moment I don't know how to look these things up. Regard, . . . Tobias -- Original: #if __GLASGOW_HASKELL__ = 609 type E = C.SomeException #else type E = C.Exception #endif -- Modified: type E = C.Exception -- Tobias Kräntzer | Scharnweberstraße 52a | 10247 Berlin Telefon: +49-30-75636668 | +49-178-1353136 XMPP: [EMAIL PROTECTED] ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] handles and foreign C functions
Hello,
suppose a simple C function like this:
void printStuff(FILE *f)
{
fprintf (f, Hello World\n);
}
In order to use it I need to import fopen and pass to it a Ptr CFile:
foreign import ccall unsafe fopen fopen :: CString - CString - IO (Ptr
CFile)
foreign import ccall unsafe fclose fclose :: Ptr CFile - IO CInt
foreign import ccall unsafe printStuff printStuff :: Ptr CFile - IO ()
main =
withCString tmp.txt $ \cpath -
withCString w $ \cmode - do
cfile - throwErrnoIfNull fopen: (fopen cpath cmode)
printStuff cfile
fclose cfile
How can I pass to printStuff a stdout FILE pointer?
If, for instance, I do:
foreign import ccall unsafe stdout c_stdout :: Ptr CFile
main =
withCString tmp.txt $ \cpath -
withCString w $ \cmode - do
printStuff c_stdout
I get a segmentation fault.
What am I missing?
TIA
Andrea
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[Haskell-cafe] gmp license == no commercial/closed source haskell software ??
I've just discovered the GMP license problem. (see http://hackage.haskell.org/trac/ghc/wiki/ReplacingGMPNotes) From my understanding, the gmp is GPL, GHC statically links it on windows. As a consequence, any program compiled using GHC must be distributed under a GPL compatible license. In the threads I've read, some workarounds are proposed on linux and OsX, but I didn't see anything on windows. Is the situation still the same ? Does anybody know a work-around to make a closed-source programm in haskell without violating the GPL ? ( Note this could block Haskell in our company. ) -- Best Regards, lionel Barret de Nazaris, = Gamr7 : Cities for Games http://www.gamr7.com ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] gmp license == no commercial/closed source haskell software ??
lionel: I've just discovered the GMP license problem. (see http://hackage.haskell.org/trac/ghc/wiki/ReplacingGMPNotes) From my understanding, the gmp is GPL, GHC statically links it on windows. As a consequence, any program compiled using GHC must be distributed under a GPL compatible license. GMP is *LGPL*. In the threads I've read, some workarounds are proposed on linux and OsX, but I didn't see anything on windows. Is the situation still the same ? Does anybody know a work-around to make a closed-source programm in haskell without violating the GPL ? It is LGPL, which is a very important distinction. It just must be possible to replace the libgmp component with another that has been modified - you can't actively prevent people replacing the libgmp component. Supporting this is trivial with a dynamically linked / DLL libgmp. With a statically linked one, it is also possible, since the API calls to libgmp are specified. This shouldn't prevent commercial use -- lots of other companies have decided this is OK. You just need to be aware of it. -- Don ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] gmp license == no commercial/closed source haskell software ??
On Wed, 2008-12-03 at 15:36 +0100, Lionel Barret De Nazaris wrote: I've just discovered the GMP license problem. (see http://hackage.haskell.org/trac/ghc/wiki/ReplacingGMPNotes) From my understanding, the gmp is GPL, GHC statically links it on windows. Lesser GPL: http://www.gnu.org/copyleft/lesser.html It doesn't actually have a section 2(c) as per the wiki. Section 4(d)0 of the LGPL is traditionally taken to allow static linking, as long as you distribute a) The source of the version of GMP you use (corresponding source), and b) Object files/libraries for your program + the GHC RTS suitable for static linking with your user's (possibly modified) builds of the distributed GMP source. jcc ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Re: ANNOUNCE: gitit 0.2 release - wiki using HAppS, git, pandoc
+++ Hugo Pacheco [Dec 03 08 09:36 ]: Good morning, I wonder if it is possible to embed regular HTML code inside gitit (on 0.3.2) pages, such as java applets like the following. APPLET CODE = GHood.class ARCHIVE = GHood.jar WIDTH = 1100 HEIGHT = 400 ALT = you should see an instance of GHood here, as an applet PARAM NAME = eventSource VALUE =factHylo.log PARAM NAME = delay VALUE =150 PARAM NAME = scale VALUE =75 /APPLET I am assuming that as a wiki, it is only possible to point to external pages. Thanks, hugo Of course you can put any HTML you like in the page template (template.html). But I assume you are asking about HTML inside the wiki pages themselves. Although markdown allows embedded HTML, gitit uses pandoc's HTML sanitization feature, so things that might be dangerous (like applets) will be filtered out and replaced by comments. You could easily modify the code to remove the santitization feature. Just change the textToPandoc function so that stateSanitizeHtml is set to False. John ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] handles and foreign C functions
Hello Andrea, Wednesday, December 3, 2008, 5:09:21 PM, you wrote: How can I pass to printStuff a stdout FILE pointer? afair, stdout syntax used to import variables. it was discussed just a day or two ago :) -- Best regards, Bulatmailto:[EMAIL PROTECTED] ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re[2]: [Haskell-cafe] gmp license == no commercial/closed source haskell software ??
Hello Don, Wednesday, December 3, 2008, 5:36:57 PM, you wrote: From my understanding, the gmp is GPL, GHC statically links it on windows. GMP is *LGPL*. Supporting this is trivial with a dynamically linked / DLL libgmp. the whole problem is that it links in statically, that reduces license to GPL -- Best regards, Bulatmailto:[EMAIL PROTECTED] ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] gmp license == no commercial/closed source haskell software ??
Hallo, Don Stewart wrote: Supporting this is trivial with a dynamically linked / DLL libgmp. With a statically linked one, it is also possible, since the API calls to libgmp are specified. Is it also possible? How? This shouldn't prevent commercial use -- lots of other companies have decided this is OK. You just need to be aware of it. They have decided this is OK as long as they can ship a shared library. Cheers, -alex http://www.ventonegro.org/ ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] handles and foreign C functions
On Wed, Dec 03, 2008 at 07:08:00PM +0300, Bulat Ziganshin wrote: Hello Andrea, Wednesday, December 3, 2008, 5:09:21 PM, you wrote: How can I pass to printStuff a stdout FILE pointer? afair, stdout syntax used to import variables. it was discussed just a day or two ago :) you mean this, I think: foreign import ccall unsafe stdout c_stdout :: Ptr CFile (my fault with the cutpaste of the previous message). This is causing the segmentation fault I was talking about. Thanks, Andrea ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re[2]: [Haskell-cafe] handles and foreign C functions
Hello Andrea,
Wednesday, December 3, 2008, 7:23:20 PM, you wrote:
either some error in the code (i neevr used this feature) or stdout
may be defile by a macro. can you try to define function for it:
FILE *out() {return stdout;}
On Wed, Dec 03, 2008 at 07:08:00PM +0300, Bulat Ziganshin wrote:
Hello Andrea,
Wednesday, December 3, 2008, 5:09:21 PM, you wrote:
How can I pass to printStuff a stdout FILE pointer?
afair, stdout syntax used to import variables. it was discussed
just a day or two ago :)
you mean this, I think:
foreign import ccall unsafe stdout c_stdout :: Ptr CFile
(my fault with the cutpaste of the previous message).
This is causing the segmentation fault I was talking about.
Thanks,
Andrea
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--
Best regards,
Bulatmailto:[EMAIL PROTECTED]
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Re: [Haskell-cafe] handles and foreign C functions
Hello Bulat,
On Wed, Dec 03, 2008 at 07:26:39PM +0300, Bulat Ziganshin wrote:
either some error in the code (i neevr used this feature) or stdout
may be defile by a macro.
the second you said:
/* C89/C99 say they're macros. Make them happy. */
(from stdio.h)
can you try to define function for it:
FILE *out() {return stdout;}
This does the trick.
Thank you once again.
Andrea
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Re: [Haskell-cafe] Problem building HXQ on Mac OS 10.5.5
On Tue, Dec 2, 2008 at 9:49 AM, Tobias Kräntzer [EMAIL PROTECTED] wrote: Hi, I'm new to haskell and wonted to start tinkering a bit with this language, specifically with HXQ. I have installed ghc with macports. Now while building HXQ I get the following error: Main.hs:20:9: Not in scope: type constructor or class `C.SomeException' Unfortunately I'm also new to Mac OS X. Before I developed on Linux. It would be great, if someone could give me a hint. I think you should be able to build it if you manually download the .tar.gz file from Hackage and then type: runghc Setup configure runghc Setup build runghc Setup install The Control.Exception module was changed in ghc-6.10.1 (specifically, in the base-4 package). HXQ's code assumes that when compiling with ghc-6.10 you're always using base-4; however, that compiler also comes with base-3.0.3 which is a compatibility package providing the same interface as previous versions of ghc. The 'cabal install' program tries to be helpful and selects base-3.0.3 (since HXQ does not specify which to use), causing the above error. I've cc'd the package author on this. A possible fix would be to use the extensible-exceptions package, or otherwise just copy the logic from its .cabal file. -Judah ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Re: ANNOUNCE: gitit 0.2 release - wiki using HAppS, git, pandoc
yes, I am talking about inserting HTML inside the wiki.Thanks, I will check on that and report back, hugo On Wed, Dec 3, 2008 at 3:44 PM, John MacFarlane [EMAIL PROTECTED] wrote: +++ Hugo Pacheco [Dec 03 08 09:36 ]: Good morning, I wonder if it is possible to embed regular HTML code inside gitit (on 0.3.2) pages, such as java applets like the following. APPLET CODE = GHood.class ARCHIVE = GHood.jar WIDTH = 1100 HEIGHT = 400 ALT = you should see an instance of GHood here, as an applet PARAM NAME = eventSource VALUE =factHylo.log PARAM NAME = delay VALUE =150 PARAM NAME = scale VALUE =75 /APPLET I am assuming that as a wiki, it is only possible to point to external pages. Thanks, hugo Of course you can put any HTML you like in the page template (template.html). But I assume you are asking about HTML inside the wiki pages themselves. Although markdown allows embedded HTML, gitit uses pandoc's HTML sanitization feature, so things that might be dangerous (like applets) will be filtered out and replaced by comments. You could easily modify the code to remove the santitization feature. Just change the textToPandoc function so that stateSanitizeHtml is set to False. John -- www.di.uminho.pt/~hpacheco ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Gluing pipes
From time to time, I've wanted to have a more pleasant way of writing point-free compositions of curried functions. One might want to transform both the first and second arguments, for instance, or only the third argument, of a curried function. I've never known a (non-cryptic) way to do this. For example, given: f :: a - b - c g :: a1 - a h :: b2 - b I'd like to be able to write something like: \ x y - f (g x) (h y) in a way that is both point-free and applicative. In other words, I'd like to apply a function to pipes or transformers rather than to values. Recent posts by Conal Elliott [1,2] got me thinking about this again, and I've found a simple solution. I use two of Conal's combinators: argument = flip (.) result = (.) And now we define: infixr 2 ~ f ~ g = argument f . result g infixl 1 $. ($.) = flip ($) Which lets us write: -- transform both arguments f $. g ~ h ~ id -- transform just the second argument f $. id ~ h ~ id The name ($.) is chosen to indicate that this is (roughly) a composition disguised as an application. The transformer spec to the right of ($.) looks like the type of the function to the left, and consists of a transformer for each argument and one for the result type. Of course, (~) is right associative, and id can match the entire tail in bulk, so we can also write something like: f $. g ~ id And of course, each transformer can be a pipeline, so assuming proper types, we can do things like: f $. id ~ (length.snd.unWrap) ~ wrap More details here: http://matt.immute.net/content/pointless-fun Questions: 1. Is there already another well-known way to do this? It seems a common enough problem... 2. Do these particular combinators already exist somewhere with other names? 3. Are there better names for these functions? Thanks! Matt [1] http://conal.net/blog/posts/semantic-editor-combinators/ [2] http://conal.net/blog/posts/prettier-functions-for-wrapping-and-wrapping/ ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] ANN: Real World Haskell, now shipping
Brandon S. Allbery KF8NH wrote: On 2008 Dec 2, at 14:44, Andrew Coppin wrote: Regardless, it has been my general experience that almost everything obtained from Hackage fails miserably to compile under Windows. (IIRC, one package even used a Bash script as part of the build process!) I haven't seen similar problems on Linux. (But I don't use Linux very often.) About the worst problem there was Gtk2hs being confused about some Autoconfig stuff or something... Many packages assume you have the msys / mingw stuff installed on Windows (if they work at all; those of us who don't develop on Windows wouldn't really know how to go about being compatible). According to the Cabal experts, the issue is that Windows doesn't have a standard place for keeping header files like the various POSIX environments typically do. That means anything that binds an external C library (i.e., almost all useful Haskell packages) don't easily work on Windows. I'm not sure what the solution to this is... ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] ANN: Real World Haskell, now shipping
Jason Dusek wrote: Andrew Coppin [EMAIL PROTECTED] wrote: ...it has been my general experience that almost everything obtained from Hackage fails miserably to compile under Windows. (IIRC, one package even used a Bash script as part of the build process!) I haven't seen similar problems on Linux. (But I don't use Linux very often.) I try very hard to make my programs work on Windows; and indeed, one of things I appreciate about Haskell is how easy it is to create binaries and packages that are cross platform. Certainly the one or two pure Haskell packages out there (e.g., PureMD5) seem to build without issue. The trouble is that almost all useful Haskell packages are bindings to C libraries, and that varies by platform. :-( However, the only time I actually use Windows is to build and test my Haskell packages. Most of the people on this list -- and I wager, most people on the mailing lists for any open source programming language -- are working on a NIXalike; we can work with bug reports, but we can't very well be the fabled many eyeballs on a platform we don't use. Ask not what your Haskell can do for you, but rather what you can do for your Haskell :) As I say, last time I tried this, I'd just failed to build half a dozen other interesting packages, so by the time I'd got to trying to get database access working, I was frustrated to the point of giving up. (The IRC channel is great - but only if the people you need to speak to happen to be there at the exact moment when you ask your question. Apparently I'm in a different timezone to everybody else.) About the worst problem there was Gtk2hs being confused about some Autoconfig stuff or something... Well, what else would a package built with GNU toolchain be confused about? Is there some miraculous language and package system for it where compiling libraries made with autotools is just a snap on Windows? No no - I meant the worst problem _on Linux_ was Gtk2hs getting confused. (It built OK on OpenSuSE, but appears not to like Ubuntu very much.) ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Projects that depend on the vty package?
Hello, For further development of the vty package I'm really only paying attention to the requirements that fall out of the Yi project. Are there any other projects that depend on the vty package? In addition, the vty project has it's own wiki: http://trac.haskell.org/vty/ Right now there isn't much information there but it is a great place to send bug reports or enhancement requests if you have them. Cheers, Corey O'Connor ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Re: ANNOUNCE: gitit 0.2 release - wiki using HAppS, git, pandoc
On a different level, I was trying the wiki on my laptop, but have now installed it in a remote server. However, with the same configurations, I can create users but not log in, it simply returns to the front page. It is hosted at http://haskell.di.uminho.pt:8080 It does not seem to be a permissions problem, I gave full permissions to all gitit files and nothing changed. Any idea why? Also being an headache is configuring apache reverse proxy for it: http://haskell.di.uminho.pt/wiki/ hugo On Wed, Dec 3, 2008 at 6:03 PM, Hugo Pacheco [EMAIL PROTECTED] wrote: yes, I am talking about inserting HTML inside the wiki.Thanks, I will check on that and report back, hugo On Wed, Dec 3, 2008 at 3:44 PM, John MacFarlane [EMAIL PROTECTED] wrote: +++ Hugo Pacheco [Dec 03 08 09:36 ]: Good morning, I wonder if it is possible to embed regular HTML code inside gitit (on 0.3.2) pages, such as java applets like the following. APPLET CODE = GHood.class ARCHIVE = GHood.jar WIDTH = 1100 HEIGHT = 400 ALT = you should see an instance of GHood here, as an applet PARAM NAME = eventSource VALUE =factHylo.log PARAM NAME = delay VALUE =150 PARAM NAME = scale VALUE =75 /APPLET I am assuming that as a wiki, it is only possible to point to external pages. Thanks, hugo Of course you can put any HTML you like in the page template (template.html). But I assume you are asking about HTML inside the wiki pages themselves. Although markdown allows embedded HTML, gitit uses pandoc's HTML sanitization feature, so things that might be dangerous (like applets) will be filtered out and replaced by comments. You could easily modify the code to remove the santitization feature. Just change the textToPandoc function so that stateSanitizeHtml is set to False. John -- www.di.uminho.pt/~hpacheco -- www.di.uminho.pt/~hpacheco ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Re: ANNOUNCE: gitit 0.2 release - wiki using HAppS, git, pandoc
Solved, just something with my Safari cookies, sorry. On Wed, Dec 3, 2008 at 8:40 PM, Hugo Pacheco [EMAIL PROTECTED] wrote: On a different level, I was trying the wiki on my laptop, but have now installed it in a remote server. However, with the same configurations, I can create users but not log in, it simply returns to the front page. It is hosted at http://haskell.di.uminho.pt:8080 It does not seem to be a permissions problem, I gave full permissions to all gitit files and nothing changed. Any idea why? Also being an headache is configuring apache reverse proxy for it: http://haskell.di.uminho.pt/wiki/ hugo On Wed, Dec 3, 2008 at 6:03 PM, Hugo Pacheco [EMAIL PROTECTED] wrote: yes, I am talking about inserting HTML inside the wiki.Thanks, I will check on that and report back, hugo On Wed, Dec 3, 2008 at 3:44 PM, John MacFarlane [EMAIL PROTECTED] wrote: +++ Hugo Pacheco [Dec 03 08 09:36 ]: Good morning, I wonder if it is possible to embed regular HTML code inside gitit (on 0.3.2) pages, such as java applets like the following. APPLET CODE = GHood.class ARCHIVE = GHood.jar WIDTH = 1100 HEIGHT = 400 ALT = you should see an instance of GHood here, as an applet PARAM NAME = eventSource VALUE =factHylo.log PARAM NAME = delay VALUE =150 PARAM NAME = scale VALUE =75 /APPLET I am assuming that as a wiki, it is only possible to point to external pages. Thanks, hugo Of course you can put any HTML you like in the page template (template.html). But I assume you are asking about HTML inside the wiki pages themselves. Although markdown allows embedded HTML, gitit uses pandoc's HTML sanitization feature, so things that might be dangerous (like applets) will be filtered out and replaced by comments. You could easily modify the code to remove the santitization feature. Just change the textToPandoc function so that stateSanitizeHtml is set to False. John -- www.di.uminho.pt/~hpacheco -- www.di.uminho.pt/~hpacheco -- www.di.uminho.pt/~hpacheco ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] library to process zip files
On Thu, Dec 04, 2008 at 11:56:10AM +1300, Yuriy wrote: Hi, Is there any haskell library to work with ZIP file format? Thanks, Yuriy ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] library to process zip files
http://hackage.haskell.org/cgi-bin/hackage-scripts/package/zip-archive On Wed, Dec 3, 2008 at 5:59 PM, Yuriy [EMAIL PROTECTED] wrote: On Thu, Dec 04, 2008 at 11:56:10AM +1300, Yuriy wrote: Hi, Is there any haskell library to work with ZIP file format? Thanks, Yuriy ___ 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] is there something special about the Num instance?
module Test where --why does this work: data Test = Test class Foo t where foo :: Num v = t - v - IO () instance Foo Test where foo _ 1 = print $ one foo _ _ = print $ not one --but this doesn't? class Bar t where bar :: Foo v = t - v - IO () instance Bar Test where bar _ Test = print $ test bar _ _ = print $ not test ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] library to process zip files
Almost as fast as typing proper google query :) Thanks. On Wed, Dec 03, 2008 at 06:01:59PM -0500, Jeff Heard wrote: http://hackage.haskell.org/cgi-bin/hackage-scripts/package/zip-archive On Wed, Dec 3, 2008 at 5:59 PM, Yuriy [EMAIL PROTECTED] wrote: On Thu, Dec 04, 2008 at 11:56:10AM +1300, Yuriy wrote: Hi, Is there any haskell library to work with ZIP file format? Thanks, Yuriy ___ 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] is there something special about the Num instance?
Numeric literals are special. Their type is (Num t) = t, so it can belong to any type that is instance of Num. Whereas Test belongs to Test type only so you cannot call bar on any instance of Foo. So your pattern constrains type signature of bar more then it is constrained by class declaration. On Wed, Dec 03, 2008 at 03:05:37PM -0800, Anatoly Yakovenko wrote: module Test where --why does this work: data Test = Test class Foo t where foo :: Num v = t - v - IO () instance Foo Test where foo _ 1 = print $ one foo _ _ = print $ not one --but this doesn't? class Bar t where bar :: Foo v = t - v - IO () instance Bar Test where bar _ Test = print $ test bar _ _ = print $ not test ___ 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] is there something special about the Num instance?
Am Donnerstag, 4. Dezember 2008 00:05 schrieb Anatoly Yakovenko: module Test where --why does this work: data Test = Test class Foo t where foo :: Num v = t - v - IO () instance Foo Test where foo _ 1 = print $ one foo _ _ = print $ not one --but this doesn't? class Bar t where bar :: Foo v = t - v - IO () instance Bar Test where bar _ Test = print $ test bar _ _ = print $ not test Because bar has to work for all types which belong to class Foo, but actually uses the type Test. This is what the error message Test.hs:18:10: Couldn't match expected type `v' against inferred type `Test' `v' is a rigid type variable bound by the type signature for `bar' at Test.hs:15:15 In the pattern: Test In the definition of `bar': bar _ Test = print $ test In the definition for method `bar' tells you. In the signature of bar, you've said that bar works for all types v which are members of Foo. Test is a monomorphic value of type Test, so it can't have type v for all v which belong to Foo. It doesn't matter that there is so far only the one instance of Foo, there could be others defined in other modules. The first works because the type of 1 in the definition of foo is defaulted to Integer (or whatever you specified in the default declaration). ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] is there something special about the Num instance?
Yes; I had a similar question, and it turns out Num is special, or
rather, pattern matching on integer literals is special. See the
thread
http://www.nabble.com/Pattern-matching-on-numbers--td20571034.html
The summary is that pattern matching on a literal integer is different
than a regular pattern match; in particular:
foo 1 = print one
foo _ = print not one
turns into
foo x = if x == fromInteger 1 then one else not one
whereas
bar Test = print Test
bar _ = print Not Test
turns into
bar x = case x of { Test - print Test ; _ - print Not Test }
In the former case, the use of (y == fromInteger 1) means that foo
works on any argument within the class Num (which requires Eq),
whereas in the latter case, the use of the constructor Test directly
turns into a requirement for a particular type for bar.
There's no way to get special pattern matching behavior for other
types; this overloading is specific to integer literals.
-- ryan
On Wed, Dec 3, 2008 at 3:05 PM, Anatoly Yakovenko [EMAIL PROTECTED] wrote:
module Test where
--why does this work:
data Test = Test
class Foo t where
foo :: Num v = t - v - IO ()
instance Foo Test where
foo _ 1 = print $ one
foo _ _ = print $ not one
--but this doesn't?
class Bar t where
bar :: Foo v = t - v - IO ()
instance Bar Test where
bar _ Test = print $ test
bar _ _ = print $ not test
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[Haskell-cafe] Re: ANNOUNCE: gitit 0.2 release - wiki using HAppS, git, pandoc
Hmm, I think I finally see the real problem. At some point when logged in, the session expires and the wiki prompts again for the login information. However, the cookies still assume we are logged in and do not allow me to log in again. The solution is to remove the cookies for the wiki server. I think this is some kind of bug with the session state. Regards, hugo On Wed, Dec 3, 2008 at 9:29 PM, Hugo Pacheco [EMAIL PROTECTED] wrote: Solved, just something with my Safari cookies, sorry. On Wed, Dec 3, 2008 at 8:40 PM, Hugo Pacheco [EMAIL PROTECTED] wrote: On a different level, I was trying the wiki on my laptop, but have now installed it in a remote server. However, with the same configurations, I can create users but not log in, it simply returns to the front page. It is hosted at http://haskell.di.uminho.pt:8080 It does not seem to be a permissions problem, I gave full permissions to all gitit files and nothing changed. Any idea why? Also being an headache is configuring apache reverse proxy for it: http://haskell.di.uminho.pt/wiki/ hugo On Wed, Dec 3, 2008 at 6:03 PM, Hugo Pacheco [EMAIL PROTECTED] wrote: yes, I am talking about inserting HTML inside the wiki.Thanks, I will check on that and report back, hugo On Wed, Dec 3, 2008 at 3:44 PM, John MacFarlane [EMAIL PROTECTED]wrote: +++ Hugo Pacheco [Dec 03 08 09:36 ]: Good morning, I wonder if it is possible to embed regular HTML code inside gitit (on 0.3.2) pages, such as java applets like the following. APPLET CODE = GHood.class ARCHIVE = GHood.jar WIDTH = 1100 HEIGHT = 400 ALT = you should see an instance of GHood here, as an applet PARAM NAME = eventSource VALUE =factHylo.log PARAM NAME = delay VALUE =150 PARAM NAME = scale VALUE =75 /APPLET I am assuming that as a wiki, it is only possible to point to external pages. Thanks, hugo Of course you can put any HTML you like in the page template (template.html). But I assume you are asking about HTML inside the wiki pages themselves. Although markdown allows embedded HTML, gitit uses pandoc's HTML sanitization feature, so things that might be dangerous (like applets) will be filtered out and replaced by comments. You could easily modify the code to remove the santitization feature. Just change the textToPandoc function so that stateSanitizeHtml is set to False. John -- www.di.uminho.pt/~hpacheco -- www.di.uminho.pt/~hpacheco -- www.di.uminho.pt/~hpacheco -- www.di.uminho.pt/~hpacheco ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] ANN: Real World Haskell, now shipping
On Wed, Dec 3, 2008 at 11:53 AM, Andrew Coppin [EMAIL PROTECTED] wrote: Brandon S. Allbery KF8NH wrote: On 2008 Dec 2, at 14:44, Andrew Coppin wrote: Regardless, it has been my general experience that almost everything obtained from Hackage fails miserably to compile under Windows. (IIRC, one package even used a Bash script as part of the build process!) I haven't seen similar problems on Linux. (But I don't use Linux very often.) About the worst problem there was Gtk2hs being confused about some Autoconfig stuff or something... Many packages assume you have the msys / mingw stuff installed on Windows (if they work at all; those of us who don't develop on Windows wouldn't really know how to go about being compatible). According to the Cabal experts, the issue is that Windows doesn't have a standard place for keeping header files like the various POSIX environments typically do. That means anything that binds an external C library (i.e., almost all useful Haskell packages) don't easily work on Windows. I'm not sure what the solution to this is... Have you tried passing the --extra-include-dirs and --extra-lib-dirs arguments to 'cabal install'? On OS X, that's how I deal with the macports package manager which puts all library files under /opt/local. I've found the process pretty painless. -Judah ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] is there something special about the Num instance?
Thanks for your help.
On Wed, Dec 3, 2008 at 3:47 PM, Ryan Ingram [EMAIL PROTECTED] wrote:
Yes; I had a similar question, and it turns out Num is special, or
rather, pattern matching on integer literals is special. See the
thread
http://www.nabble.com/Pattern-matching-on-numbers--td20571034.html
The summary is that pattern matching on a literal integer is different
than a regular pattern match; in particular:
foo 1 = print one
foo _ = print not one
turns into
foo x = if x == fromInteger 1 then one else not one
whereas
bar Test = print Test
bar _ = print Not Test
turns into
bar x = case x of { Test - print Test ; _ - print Not Test }
In the former case, the use of (y == fromInteger 1) means that foo
works on any argument within the class Num (which requires Eq),
whereas in the latter case, the use of the constructor Test directly
turns into a requirement for a particular type for bar.
There's no way to get special pattern matching behavior for other
types; this overloading is specific to integer literals.
-- ryan
On Wed, Dec 3, 2008 at 3:05 PM, Anatoly Yakovenko [EMAIL PROTECTED] wrote:
module Test where
--why does this work:
data Test = Test
class Foo t where
foo :: Num v = t - v - IO ()
instance Foo Test where
foo _ 1 = print $ one
foo _ _ = print $ not one
--but this doesn't?
class Bar t where
bar :: Foo v = t - v - IO ()
instance Bar Test where
bar _ Test = print $ test
bar _ _ = print $ not test
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Re: [Haskell-cafe] Re: ANNOUNCE: gitit 0.2 release - wiki using HAppS, git, pandoc
This is pretty cool. I was wondering how much work would it be for gitit to be able to use markdown from the comment sections in source files? It would be a really good way to manage documentation. Basically I would like to be able to point gitit at an existing git repo, and have it provide a wiki interface to all the documentation so developers can view and modify it. Thanks, Anatoly 2008/12/3 Hugo Pacheco [EMAIL PROTECTED]: Hmm, I think I finally see the real problem. At some point when logged in, the session expires and the wiki prompts again for the login information. However, the cookies still assume we are logged in and do not allow me to log in again. The solution is to remove the cookies for the wiki server. I think this is some kind of bug with the session state. Regards, hugo On Wed, Dec 3, 2008 at 9:29 PM, Hugo Pacheco [EMAIL PROTECTED] wrote: Solved, just something with my Safari cookies, sorry. On Wed, Dec 3, 2008 at 8:40 PM, Hugo Pacheco [EMAIL PROTECTED] wrote: On a different level, I was trying the wiki on my laptop, but have now installed it in a remote server. However, with the same configurations, I can create users but not log in, it simply returns to the front page. It is hosted at http://haskell.di.uminho.pt:8080 It does not seem to be a permissions problem, I gave full permissions to all gitit files and nothing changed. Any idea why? Also being an headache is configuring apache reverse proxy for it: http://haskell.di.uminho.pt/wiki/ hugo On Wed, Dec 3, 2008 at 6:03 PM, Hugo Pacheco [EMAIL PROTECTED] wrote: yes, I am talking about inserting HTML inside the wiki. Thanks, I will check on that and report back, hugo On Wed, Dec 3, 2008 at 3:44 PM, John MacFarlane [EMAIL PROTECTED] wrote: +++ Hugo Pacheco [Dec 03 08 09:36 ]: Good morning, I wonder if it is possible to embed regular HTML code inside gitit (on 0.3.2) pages, such as java applets like the following. APPLET CODE = GHood.class ARCHIVE = GHood.jar WIDTH = 1100 HEIGHT = 400 ALT = you should see an instance of GHood here, as an applet PARAM NAME = eventSource VALUE =factHylo.log PARAM NAME = delay VALUE =150 PARAM NAME = scale VALUE =75 /APPLET I am assuming that as a wiki, it is only possible to point to external pages. Thanks, hugo Of course you can put any HTML you like in the page template (template.html). But I assume you are asking about HTML inside the wiki pages themselves. Although markdown allows embedded HTML, gitit uses pandoc's HTML sanitization feature, so things that might be dangerous (like applets) will be filtered out and replaced by comments. You could easily modify the code to remove the santitization feature. Just change the textToPandoc function so that stateSanitizeHtml is set to False. John -- www.di.uminho.pt/~hpacheco -- www.di.uminho.pt/~hpacheco -- www.di.uminho.pt/~hpacheco -- www.di.uminho.pt/~hpacheco ___ 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: ANNOUNCE: gitit 0.2 release - wiki using HAppS, git, pandoc
+++ Anatoly Yakovenko [Dec 03 08 17:03 ]: This is pretty cool. I was wondering how much work would it be for gitit to be able to use markdown from the comment sections in source files? It would be a really good way to manage documentation. Basically I would like to be able to point gitit at an existing git repo, and have it provide a wiki interface to all the documentation so developers can view and modify it. You can do something like that now. You can specify the repository directory in a configuration file. Anything in the repository (even in subdirectories) with a .page extension will be served up as a wiki page. So you'd have to use a .page extension for your markdown documentation. Everything else in the repository will appear in the index. Source code files will be automatically syntax-highlighted, and you can even view history and diffs through the wiki interface. But I guess what you want is for the documentation to be in comments in the source files themselves, not in separate files. I'm not sure how to do that -- would the idea be to show just the documentation, perhaps marked off with some special notation, and not the source? But then we lose a nice feature, the ability to view source files. I'm open to ideas. Soon, gitit will contain support for pages in markdownish literate Haskell, which might be the best of both worlds for Haskell projects. (They'd still need the .page extension, since some .lhs files are LaTeX lhs, but one could use hard links, or there could be a configuration option to treat .lhs files as wiki pages.) John ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Re: ANNOUNCE: gitit 0.2 release - wiki using HAppS, git, pandoc
On Wed, Dec 3, 2008 at 5:54 PM, John MacFarlane [EMAIL PROTECTED] wrote: +++ Anatoly Yakovenko [Dec 03 08 17:03 ]: This is pretty cool. I was wondering how much work would it be for gitit to be able to use markdown from the comment sections in source files? It would be a really good way to manage documentation. Basically I would like to be able to point gitit at an existing git repo, and have it provide a wiki interface to all the documentation so developers can view and modify it. You can do something like that now. You can specify the repository directory in a configuration file. Anything in the repository (even in subdirectories) with a .page extension will be served up as a wiki page. So you'd have to use a .page extension for your markdown documentation. Everything else in the repository will appear in the index. Source code files will be automatically syntax-highlighted, and you can even view history and diffs through the wiki interface. cool. Does it add any other files to the reposoitory? Could you use it over a read only one? But I guess what you want is for the documentation to be in comments in the source files themselves, not in separate files. I'm not sure how to do that -- would the idea be to show just the documentation, perhaps marked off with some special notation, and not the source? But then we lose a nice feature, the ability to view source files. I'm open to ideas. I was thinking it would show both the documentation and the source, but have the documentation as the editable part of the page. Do you think that's possible? Or it could parse out the documentation and show 2 dynamically generated pages, one for just the docs and one for the source. But i think it would be useful to be able to see the documentation in the context of the source that its referring to. Unfortunately I am not a web guy, so i have no idea how hard any of this would be :). ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: Re[2]: [Haskell-cafe] GHC on Fedora 10 - getMBlock: mmap: Permission denied
I had fun with SELinux when using Haskell for CGI programs. The default SELinux policy forbids CGI programs that execute code in their data segment. I had to write a policy module that allowed httpd_sys_script_t self:process execmem. Oh joy. John ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Re: ANNOUNCE: gitit 0.2 release - wiki using HAppS, git, pandoc
I think that Anatoly was suggestion a bridge between markdown and haddock syntax. Of course gitit would read haddock-documented sources and generate different results than haddock itself (showing highlighted source code is the most significant). Being practical, this is very close to the markdownish literate haskell you are suggesting. hugo On Thu, Dec 4, 2008 at 1:54 AM, John MacFarlane [EMAIL PROTECTED] wrote: +++ Anatoly Yakovenko [Dec 03 08 17:03 ]: This is pretty cool. I was wondering how much work would it be for gitit to be able to use markdown from the comment sections in source files? It would be a really good way to manage documentation. Basically I would like to be able to point gitit at an existing git repo, and have it provide a wiki interface to all the documentation so developers can view and modify it. You can do something like that now. You can specify the repository directory in a configuration file. Anything in the repository (even in subdirectories) with a .page extension will be served up as a wiki page. So you'd have to use a .page extension for your markdown documentation. Everything else in the repository will appear in the index. Source code files will be automatically syntax-highlighted, and you can even view history and diffs through the wiki interface. But I guess what you want is for the documentation to be in comments in the source files themselves, not in separate files. I'm not sure how to do that -- would the idea be to show just the documentation, perhaps marked off with some special notation, and not the source? But then we lose a nice feature, the ability to view source files. I'm open to ideas. Soon, gitit will contain support for pages in markdownish literate Haskell, which might be the best of both worlds for Haskell projects. (They'd still need the .page extension, since some .lhs files are LaTeX lhs, but one could use hard links, or there could be a configuration option to treat .lhs files as wiki pages.) John ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe -- www.di.uminho.pt/~hpacheco ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Re: ANNOUNCE: gitit 0.2 release - wiki using HAppS, git, pandoc
Being practical, this is very close to the markdownish literate haskell you are suggesting. hugo yea, i agree. But is there any way to generalize this to non haskell projects? ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] ANN: Real World Haskell, now shipping
andrewcoppin: Jason Dusek wrote: Andrew Coppin [EMAIL PROTECTED] wrote: ...it has been my general experience that almost everything obtained from Hackage fails miserably to compile under Windows. (IIRC, one package even used a Bash script as part of the build process!) I haven't seen similar problems on Linux. (But I don't use Linux very often.) I try very hard to make my programs work on Windows; and indeed, one of things I appreciate about Haskell is how easy it is to create binaries and packages that are cross platform. Certainly the one or two pure Haskell packages out there (e.g., PureMD5) seem to build without issue. The trouble is that almost all useful Haskell packages are bindings to C libraries, and that varies by platform. :-( However, the only time I actually use Windows is to build and test my Haskell packages. Most of the people on this list -- and I wager, most people on the mailing lists for any open source programming language -- are working on a NIXalike; we can work with bug reports, but we can't very well be the fabled many eyeballs on a platform we don't use. Ask not what your Haskell can do for you, but rather what you can do for your Haskell :) As I say, last time I tried this, I'd just failed to build half a dozen other interesting packages, so by the time I'd got to trying to get database access working, I was frustrated to the point of giving up. Do you mail the maintainers when there's a bulid failure? There's around 1000 packages on hackage now, and we don't have a build farm, so you can make a real difference by mailing authors when their package fails on windows. -- Don ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: Re[2]: [Haskell-cafe] gmp license == no commercial/closed source haskell software ??
Bulat Ziganshin [EMAIL PROTECTED] wrote: Don wrote: Lionel wrote: From my understanding, the gmp is GPL, GHC statically links it on windows. GMP is *LGPL*. Supporting this is trivial with a dynamically linked / DLL libgmp. the whole problem is that it links in statically, that reduces license to GPL Jonathan Cast suggests earlier that there is some wiggle room allowed in 4/(d), even for statically linked programs: d) Do one of the following: 0) Convey the Minimal Corresponding Source under the terms of this License, and the Corresponding Application Code in a form suitable for, and under terms that permit, the user to recombine or relink the Application with a modified version of the Linked Version to produce a modified Combined Work, in the manner specified by section 6 of the GNU GPL for conveying Corresponding Source. 1) Use a suitable shared library mechanism for linking with the Library. A suitable mechanism is one that (a) uses at run time a copy of the Library already present on the user's computer system, and (b) will operate properly with a modified version of the Library that is interface-compatible with the Linked Version. At first glance, (0) would seem to apply to a statically linked application; and it appears damning. However: The Minimal Corresponding Source for a Combined Work means the Corresponding Source for the Combined Work, excluding any source code for portions of the Combined Work that, considered in isolation, are based on the Application, and not on the Linked Version. The Corresponding Application Code for a Combined Work means the object code and/or source code for the Application, including any data and utility programs needed for reproducing the Combined Work from the Application, but excluding the System Libraries of the Combined Work. The latter definition admits object code and this seems to be in line with what Cast is saying. The former definition is for the actual source code that must be included -- it is somewhat vague. If an application relies heavily on multi-precision arithmetic, even through adapter classes, is everything in it based on the Linked Version? -- _jsn ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
