Re: [Haskell-cafe] [Haskell] Linker flags for foreign export.
Hi Jason, On 8 March 2011 05:28, Jason Dusek jason.du...@gmail.com wrote: gcc -g -Wall -O2 -fPIC -Wall -o import \ -I/usr/lib/ghc-6.12.1/include/ \ import.c exports.so In my experience, the easiest way to do this is to use gcc to build object files from C source files, and then specify those object files on the ghc command line in order to get GHC to do the linking step. This will deal with linking in the correct RTS and, if you specify appropriate -package flags, dependent packages as well. If you want a C main function then see user guide section 8.2.1.1 at http://www.haskell.org/ghc/docs/latest/html/users_guide/ffi-ghc.html. Cheers, Max ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Questions on list administration
Karthick Gururaj karthick.guru...@gmail.com writes: You are not allowed to post to this mailing list, and your message has been automatically rejected. If you think that your messages are being rejected in error, contact the mailing list owner at haskell-cafe-ow...@haskell.org. As it says on the Google about page, only members may post to the list. Ideally, the Google groups interface should add you as a member, or otherwise perform some magic to allow you to post, but perhaps this requires more than sufficiently advanced technology... Funny thing is, google reports that my post was successful, and my post was visible on google groups even after I signed out from my google account. Possibly, posts via Google goes via a cache? Can I ask a couple of changes be done to help others like me? a. In google groups - https://groups.google.com/group/haskell-cafe/about - add a link to the haskell.org - Mailing lists for more info. I don't know how Google maintains this page, and I'm not sure whoever is the list owner does either. If you can find out how to modify this, I'm sure nobody would object to adding that information. b. Let users join from google groups interface, or if this is not possible, mention that in the about page Yes, but this, too, is an issue with Google groups, and not the Haskell mailing lists. c. Change the contents of the reject email (reproduced above) to include the following: If you want to subscribe to the Haskell Cafe mailing list, please visit http://www.haskell.org/mailman/listinfo/haskell-cafe; Well, you don't have to use the web interface to subscribe, but some information like that would be useful, and I believe this is easy to set up (we're using Mailman, I believe?). -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] Haskell IDE
The lazy path: You can also just download and install the binaries for your platform at http://leksah.org/download.html. From experience, I guess that most if not all of the capabilities will work with your version of GHC (except some features more tightly integrated with the compiler, such is GHCI. 2011/3/7 Daniel Fischer daniel.is.fisc...@googlemail.com On Monday 07 March 2011 16:08:01, Alberto G. Corona wrote: I use leksah, and I want to say thanks to the people that maintain it. I want also to encourage them to continuing its valuable work. from the last release of Leksah, I particulary appreciate its: Multiplatform support Ease of installation in all platforms including windows capability to works with many cabal packages in a single workspace its detection of dependencies and rebuilding of the affected packages Integration of GHCI and the GHCI debugger integrated building of documentation referencing and navigation trough the source of the installed packages and of course all the other traditional IDE capabilities That sounds nice, so I thought I'd try out leksah again. Unfortunately, the dependencies rule out GHC-7 (base 4.3, Cabal 1.9, containers 0.4 were the ones that sprang to the eyes immediately). Bummer Maybe someone could try relaxing the bounds and build it with GHC-7, and - if it works - upload a new version? (I could try if I get a go-ahead from Hamish or Jürgen) ___ Leksah mailing list lek...@projects.haskell.org http://projects.haskell.org/cgi-bin/mailman/listinfo/leksah ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] have anyone tried GHC 7.0.2
What does ghc-pkg list and ghc-pkg check say? Cabal-1.10.1.0, directory-1.1.0.0 and process-1.0.1.5 should be there after installation of GHC 7.0.2. (I've actually installed cabal-install-0.10.0 using an older cabal, but that does not work on macs and may not be the recommended way.) I think I've used http://www.galois.com/~dons/code/2011.2.0.0/haskell-platform-2011.2.0.0.tar.gz from http://www.galois.com/~dons/code/2011.2.0.0/, but they are not official yet. C. Am 08.03.2011 19:20, schrieb Qi Qi: Hi, After I installed GHC 7.0.2 and cabal-install 0.10.0 using Cabal library 1.10.1, I found that some package failed to install. For example like Happy, I got the following error: cabal install happy Resolving dependencies... command line: cannot satisfy -package Cabal-1.10.1.0: Cabal-1.10.1.0-64e8f05722ea5bbdf07df2e5a3491105 is unusable due to missing or recursive dependencies: directory-1.1.0.0-85d1d0f9d96dffdacf64f3cc6fba6f2f process-1.0.1.5-4cab1bf0666275ac101dd48c7565b64c (use -v for more information) cabal: Error: some packages failed to install: happy-1.18.6 failed during the configure step. The exception was: ExitFailure 1 Besides happy package, some other packages like ghc-mod, hmatrix also failed to install. Does anyone else have the same issue after installed ghc 7.0.2? By the way, does anyone hear anything about Haskell-platform 2011.2 ? Thanks! ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] ANNOUNCE: cinvoke 0.1 released
On Tue, Mar 08, 2011 at 01:15:26AM +, Felipe Almeida Lessa wrote: On Mon, Mar 7, 2011 at 6:32 PM, Remi Turk rt...@science.uva.nl wrote: - If you need to pass C structs (by value), you'll have to use libffi: cinvoke doesn't support them at all. What about CInvStructure[1]? I was just glancing at the documentation when I saw this. That's a part of cinvoke I have not implemented (and probably won't, just like callbacks and a few other things, at least until there is some demand for them). However, the CInvStructure functions are used to construct descriptions and instances of C structures at run-time. (think alignment issues...) Passing structures to functions using cinvoke can only be done using pointers though.[1] Cheers, Remi [1] http://www.nongnu.org/cinvoke/doc/cinvoke_8h.html#4d288cacc9bde484cad7d8ed1b76c1a5 ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] makeTokenParser + LanguageDef
Hi Haskellers, is there a fine tutorial for building a parser with parsecs (3.*) makeTokenParser and LanguageDef stuff? Klaus ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Overlaping Parsec rules
Hi Christian,
my version of parseList works currently strange.
The input {2\n2} will be parsed fine, but something like { } or so fails
with 'expecting space or }'.
The redefinition of space is not necessary, it was copied from another tutorial
code. How I write a version of parseGml that get gml token separated by any
white space (space, tab, newline)?
Thanks
-Ursprüngliche Nachricht-
Von: Christian Maeder [mailto:christian.mae...@dfki.de]
Gesendet: Montag, 7. März 2011 14:18
An: Hauschild, Klaus (EXT)
Cc: haskell-cafe@haskell.org
Betreff: Re: Overlaping Parsec rules
Am 07.03.2011 13:48, schrieb Hauschild, Klaus (EXT):
Thanks Christian,
I adapted the keyword parser and now n - negi does not occur.
But there are still other problems to solve. If I activate the parseFunction
the parser will answer to fact.gml unexpected end of input, expecting space
or }.
Your redefinition of spaces (= skipMany1 space) is problematic and:
parseList = sepBy parseGml' spaces
Allow for the original (optional) spaces after parseGml':
parseGml'' = liftM2 const parseGml' spaces
parseList = many parseGml''
C.
P.S. why do you call? many (noneOf )
manyTill anyChar newline
or just: many (noneOf \n)
(a trailing newline will be skipped by spaces)
Any ideas?
-Ursprüngliche Nachricht-
Von: Christian Maeder [mailto:christian.mae...@dfki.de]
Gesendet: Montag, 7. März 2011 12:23
An: Hauschild, Klaus (EXT)
Cc: haskell-cafe@haskell.org
Betreff: Re: Overlaping Parsec rules
You should parse keywords using:
keyword s = try (string s) notFollowedBy (letter | digit)
C.
Am 07.03.2011 11:34, schrieb Hauschild, Klaus (EXT):
Hi,
to solve this ICFP task _http://www.cs.cornell.edu/icfp/task.htm_ I'm
currnetly working on the parser. With the hint from Thu (reading Phillip
Wadlers monadic parser paper) and consulting
_http://en.wikibooks.org/wiki/Write_Yourself_a_Scheme_in_48_Hours/Parsing_
I produce a first working version of the parser.
After this great moment I completed the token definition and near all
parsing rules. For the complete code have a look at
_http://code.google.com/p/hgmltracer/source/browse/#svn%2Ftrunk%2FhGmlTracer_
data GmlToken =
-- structures
FunctionToken TokenSequence |
ArrayToken TokenSequence|
-- control operators
ApplyToken |
IfToken |
-- number operators
AddiToken |
AddfToken |
ACosToken |
ASinToken |
ClampfToken |
CosToken|
DiviToken |
DivfToken |
EqiToken|
EqfToken|
FloorToken |
FracToken |
LessiToken |
LessfToken |
ModiToken |
MuliToken |
MulfToken |
NegiToken |
NegfToken |
ToRealToken |
SinToken|
SqrtToken |
SubiToken |
SubfToken |
-- points
GetXToken |
GetYToken |
GetZToken |
PointToken |
-- arrays
GetToken|
LengthToken |
-- environment
IdentifierToken String |
BinderToken String |
-- types
BoolToken Bool |
IntToken Int|
RealToken Double|
StringToken String deriving Show
And
parseGml :: String - [GmlToken]
parseGml input = case parse parseList gml input of
Left err - error (Parse error: ++ (show err))
Right gml - gml
parseList = sepBy parseGml' spaces
parseGml' =
-- structures
--parseFunction
--| parseArray
-- control operators
Re: [Haskell-cafe] I think I've found a regression in Haskell Platform, but what do I do next?
On Tue, 2011-02-22 at 07:12 -0800, Johan Tibell wrote: On Tue, Feb 22, 2011 at 7:08 AM, Nick Frolov n...@mkmks.org wrote: Something has definitely changed between these two ghc versions. Since I've spent considerable amount of time on finding a workaround for the problem, I'd like to file a real bug report, but I'm not completely sure where to do it because there are several pieces of software involved (ghc itself, 'process', 'satchmo' and 'minisat2' SAT solver). Could somebody guide me please? There were a few I/O manager related bugs, one related to forking processes. These should be fixed in GHC 7.0.2 (and the next HP release), due soon. I've just reproduced the bug with GHC 7.0.2. It seems that it still has to be reported, but, again, I have no idea if it's caused by a possible regression in GHC. It could be that one of the libraries relies on the wrong behaviour of GHC 6.12.*, right? ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Overlaping Parsec rules
Am 08.03.2011 12:30, schrieb Hauschild, Klaus (EXT):
Hi Christian,
my version of parseList works currently strange.
The input {2\n2} will be parsed fine, but something like { } or so fails
with 'expecting space or }'.
You must skip (possible) spaces after {, too. (Actually after every
lexeme.)
C.
The redefinition of space is not necessary, it was copied from another
tutorial code. How I write a version of parseGml that get gml token separated
by any white space (space, tab, newline)?
Thanks
-Ursprüngliche Nachricht-
Von: Christian Maeder [mailto:christian.mae...@dfki.de]
Gesendet: Montag, 7. März 2011 14:18
An: Hauschild, Klaus (EXT)
Cc: haskell-cafe@haskell.org
Betreff: Re: Overlaping Parsec rules
Am 07.03.2011 13:48, schrieb Hauschild, Klaus (EXT):
Thanks Christian,
I adapted the keyword parser and now n - negi does not occur.
But there are still other problems to solve. If I activate the parseFunction
the parser will answer to fact.gml unexpected end of input, expecting space
or }.
Your redefinition of spaces (= skipMany1 space) is problematic and:
parseList = sepBy parseGml' spaces
Allow for the original (optional) spaces after parseGml':
parseGml'' = liftM2 const parseGml' spaces
parseList = many parseGml''
C.
P.S. why do you call? many (noneOf )
manyTill anyChar newline
or just: many (noneOf \n)
(a trailing newline will be skipped by spaces)
Any ideas?
-Ursprüngliche Nachricht-
Von: Christian Maeder [mailto:christian.mae...@dfki.de]
Gesendet: Montag, 7. März 2011 12:23
An: Hauschild, Klaus (EXT)
Cc: haskell-cafe@haskell.org
Betreff: Re: Overlaping Parsec rules
You should parse keywords using:
keyword s = try (string s) notFollowedBy (letter | digit)
C.
Am 07.03.2011 11:34, schrieb Hauschild, Klaus (EXT):
Hi,
to solve this ICFP task _http://www.cs.cornell.edu/icfp/task.htm_ I'm
currnetly working on the parser. With the hint from Thu (reading Phillip
Wadlers monadic parser paper) and consulting
_http://en.wikibooks.org/wiki/Write_Yourself_a_Scheme_in_48_Hours/Parsing_
I produce a first working version of the parser.
After this great moment I completed the token definition and near all
parsing rules. For the complete code have a look at
_http://code.google.com/p/hgmltracer/source/browse/#svn%2Ftrunk%2FhGmlTracer_
data GmlToken =
-- structures
FunctionToken TokenSequence |
ArrayToken TokenSequence|
-- control operators
ApplyToken |
IfToken |
-- number operators
AddiToken |
AddfToken |
ACosToken |
ASinToken |
ClampfToken |
CosToken|
DiviToken |
DivfToken |
EqiToken|
EqfToken|
FloorToken |
FracToken |
LessiToken |
LessfToken |
ModiToken |
MuliToken |
MulfToken |
NegiToken |
NegfToken |
ToRealToken |
SinToken|
SqrtToken |
SubiToken |
SubfToken |
-- points
GetXToken |
GetYToken |
GetZToken |
PointToken |
-- arrays
GetToken|
LengthToken |
-- environment
IdentifierToken String |
BinderToken String |
-- types
BoolToken Bool |
IntToken Int|
RealToken Double|
StringToken String deriving Show
And
parseGml :: String - [GmlToken]
parseGml input = case parse parseList gml input of
Left err - error (Parse error: ++ (show err))
Right gml - gml
parseList = sepBy parseGml' spaces
Re: [Haskell-cafe] Overlaping Parsec rules
In
http://code.google.com/p/hgmltracer/source/browse/trunk/hGmlTracer/src/Gml/Parse.hs
I see identifier - many (noneOf ). You should at least consume one
character by using many1! This also allows to call many parseGml''
later.
C.
Am 08.03.2011 12:30, schrieb Hauschild, Klaus (EXT):
Hi Christian,
my version of parseList works currently strange.
The input {2\n2} will be parsed fine, but something like { } or so fails
with 'expecting space or }'.
The redefinition of space is not necessary, it was copied from another
tutorial code. How I write a version of parseGml that get gml token separated
by any white space (space, tab, newline)?
Thanks
-Ursprüngliche Nachricht-
Von: Christian Maeder [mailto:christian.mae...@dfki.de]
Gesendet: Montag, 7. März 2011 14:18
An: Hauschild, Klaus (EXT)
Cc: haskell-cafe@haskell.org
Betreff: Re: Overlaping Parsec rules
Am 07.03.2011 13:48, schrieb Hauschild, Klaus (EXT):
Thanks Christian,
I adapted the keyword parser and now n - negi does not occur.
But there are still other problems to solve. If I activate the parseFunction
the parser will answer to fact.gml unexpected end of input, expecting space
or }.
Your redefinition of spaces (= skipMany1 space) is problematic and:
parseList = sepBy parseGml' spaces
Allow for the original (optional) spaces after parseGml':
parseGml'' = liftM2 const parseGml' spaces
parseList = many parseGml''
C.
P.S. why do you call? many (noneOf )
manyTill anyChar newline
or just: many (noneOf \n)
(a trailing newline will be skipped by spaces)
Any ideas?
-Ursprüngliche Nachricht-
Von: Christian Maeder [mailto:christian.mae...@dfki.de]
Gesendet: Montag, 7. März 2011 12:23
An: Hauschild, Klaus (EXT)
Cc: haskell-cafe@haskell.org
Betreff: Re: Overlaping Parsec rules
You should parse keywords using:
keyword s = try (string s) notFollowedBy (letter | digit)
C.
Am 07.03.2011 11:34, schrieb Hauschild, Klaus (EXT):
Hi,
to solve this ICFP task _http://www.cs.cornell.edu/icfp/task.htm_ I'm
currnetly working on the parser. With the hint from Thu (reading Phillip
Wadlers monadic parser paper) and consulting
_http://en.wikibooks.org/wiki/Write_Yourself_a_Scheme_in_48_Hours/Parsing_
I produce a first working version of the parser.
After this great moment I completed the token definition and near all
parsing rules. For the complete code have a look at
_http://code.google.com/p/hgmltracer/source/browse/#svn%2Ftrunk%2FhGmlTracer_
data GmlToken =
-- structures
FunctionToken TokenSequence |
ArrayToken TokenSequence|
-- control operators
ApplyToken |
IfToken |
-- number operators
AddiToken |
AddfToken |
ACosToken |
ASinToken |
ClampfToken |
CosToken|
DiviToken |
DivfToken |
EqiToken|
EqfToken|
FloorToken |
FracToken |
LessiToken |
LessfToken |
ModiToken |
MuliToken |
MulfToken |
NegiToken |
NegfToken |
ToRealToken |
SinToken|
SqrtToken |
SubiToken |
SubfToken |
-- points
GetXToken |
GetYToken |
GetZToken |
PointToken |
-- arrays
GetToken|
LengthToken |
-- environment
IdentifierToken String |
BinderToken String |
-- types
BoolToken Bool |
IntToken Int|
RealToken Double|
StringToken String deriving Show
And
parseGml :: String - [GmlToken]
parseGml input = case parse parseList gml input of
Re: [Haskell-cafe] ANNOUNCE: cinvoke 0.1 released
On Sun, Mar 6, 2011 at 2:38 PM, Remi Turk rt...@science.uva.nl wrote: I am happy to finally announce cinvoke 0.1, a binding to the C library cinvoke[1], allowing functions to be loaded and called whose names and types are not known before run-time. Why? Sometimes you can't use the Haskell foreign function interface because you parse the type of the function from somewhere else, i.e. you're writing an interpreter for a language that has an FFI itself. What? The main function it exports is: cinvoke :: Symbol - RetType b - [Arg] - IO b And because code is worth a thousand words, here's a small program that uses libc to write a 1Gb buffer of random garbage to a file: module Main where import Foreign.CInvoke main = do cxt - newContext libc - loadLibrary cxt libc.so.6 malloc - loadSymbol libc malloc creat - loadSymbol libc creat write - loadSymbol libc write free - loadSymbol libc free let sz = 2^30 buf - cinvoke malloc (retPtr retVoid) [argCSize sz] fd - cinvoke creat retCInt [argString /tmp/test, argCUInt 0o644] n - cinvoke write retCSize [argCInt fd, argPtr buf, argCSize sz] cinvoke free (retPtr retVoid) [argPtr buf] It hopefully works on any machine on which cinvoke works, but has only been tested on linux x86_64. As the current version of cinvoke only installs a static library, it does not work from GHCi at the moment (without hacking cinvoke to build a shared library). More interesting examples are included in examples/ in the package. Where? Hackage: http://hackage.haskell.org/package/cinvoke Cheers, Remi [1] http://www.nongnu.org/cinvoke/ Is there any information on how this (and libffi I guess) compare to GHC's FFI in terms of performance? Is it equivalent? Once you've loaded a function with loadSymbol and are cinvoking it with various arguments, versus a plain foreign import of the same. (Also, I assume cinvoke corresponds to the FFI's 'unsafe' calls, i.e. if the function tries to call back into the GHC runtime then Bad Things will happen, and it'll block threads on the same 'Capability' if it runs too long?) ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe -- Work is punishment for failing to procrastinate effectively. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Overlaping Parsec rules
Am 08.03.2011 12:30, schrieb Hauschild, Klaus (EXT):
Hi Christian,
my version of parseList works currently strange.
The input {2\n2} will be parsed fine, but something like { } or so fails
with 'expecting space or }'.
Also } (and ], etc.) should be excluded as identifier letters.
} is the second identifier in { }. (The first one is empty.)
C.
The redefinition of space is not necessary, it was copied from another
tutorial code. How I write a version of parseGml that get gml token separated
by any white space (space, tab, newline)?
Thanks
-Ursprüngliche Nachricht-
Von: Christian Maeder [mailto:christian.mae...@dfki.de]
Gesendet: Montag, 7. März 2011 14:18
An: Hauschild, Klaus (EXT)
Cc: haskell-cafe@haskell.org
Betreff: Re: Overlaping Parsec rules
Am 07.03.2011 13:48, schrieb Hauschild, Klaus (EXT):
Thanks Christian,
I adapted the keyword parser and now n - negi does not occur.
But there are still other problems to solve. If I activate the parseFunction
the parser will answer to fact.gml unexpected end of input, expecting space
or }.
Your redefinition of spaces (= skipMany1 space) is problematic and:
parseList = sepBy parseGml' spaces
Allow for the original (optional) spaces after parseGml':
parseGml'' = liftM2 const parseGml' spaces
parseList = many parseGml''
C.
P.S. why do you call? many (noneOf )
manyTill anyChar newline
or just: many (noneOf \n)
(a trailing newline will be skipped by spaces)
Any ideas?
-Ursprüngliche Nachricht-
Von: Christian Maeder [mailto:christian.mae...@dfki.de]
Gesendet: Montag, 7. März 2011 12:23
An: Hauschild, Klaus (EXT)
Cc: haskell-cafe@haskell.org
Betreff: Re: Overlaping Parsec rules
You should parse keywords using:
keyword s = try (string s) notFollowedBy (letter | digit)
C.
Am 07.03.2011 11:34, schrieb Hauschild, Klaus (EXT):
Hi,
to solve this ICFP task _http://www.cs.cornell.edu/icfp/task.htm_ I'm
currnetly working on the parser. With the hint from Thu (reading Phillip
Wadlers monadic parser paper) and consulting
_http://en.wikibooks.org/wiki/Write_Yourself_a_Scheme_in_48_Hours/Parsing_
I produce a first working version of the parser.
After this great moment I completed the token definition and near all
parsing rules. For the complete code have a look at
_http://code.google.com/p/hgmltracer/source/browse/#svn%2Ftrunk%2FhGmlTracer_
data GmlToken =
-- structures
FunctionToken TokenSequence |
ArrayToken TokenSequence|
-- control operators
ApplyToken |
IfToken |
-- number operators
AddiToken |
AddfToken |
ACosToken |
ASinToken |
ClampfToken |
CosToken|
DiviToken |
DivfToken |
EqiToken|
EqfToken|
FloorToken |
FracToken |
LessiToken |
LessfToken |
ModiToken |
MuliToken |
MulfToken |
NegiToken |
NegfToken |
ToRealToken |
SinToken|
SqrtToken |
SubiToken |
SubfToken |
-- points
GetXToken |
GetYToken |
GetZToken |
PointToken |
-- arrays
GetToken|
LengthToken |
-- environment
IdentifierToken String |
BinderToken String |
-- types
BoolToken Bool |
IntToken Int|
RealToken Double|
StringToken String deriving Show
And
parseGml :: String - [GmlToken]
parseGml input = case parse parseList gml input of
Left err - error (Parse error: ++ (show err))
Right gml - gml
Re: [Haskell-cafe] Overlaping Parsec rules
Hi Christian,
Thank you for your help. Now the current version of Parse.hs
(http://code.google.com/p/hgmltracer/source/browse/trunk/hGmlTracer/src/Gml/Parse.hs)
works well for the test file fact.gml.
Now the last thing is parsing the different numbers (integer and float). If
have a rule for parsing integers (parseInteger = liftM (IntToken . read) $
many1 digit) but if have currently no idea how to handle floats.
-Ursprüngliche Nachricht-
Von: Christian Maeder [mailto:christian.mae...@dfki.de]
Gesendet: Dienstag, 8. März 2011 13:26
An: Hauschild, Klaus (EXT)
Cc: haskell-cafe@haskell.org
Betreff: Re: Overlaping Parsec rules
Am 08.03.2011 12:30, schrieb Hauschild, Klaus (EXT):
Hi Christian,
my version of parseList works currently strange.
The input {2\n2} will be parsed fine, but something like { } or so fails
with 'expecting space or }'.
Also } (and ], etc.) should be excluded as identifier letters.
} is the second identifier in { }. (The first one is empty.)
C.
The redefinition of space is not necessary, it was copied from another
tutorial code. How I write a version of parseGml that get gml token separated
by any white space (space, tab, newline)?
Thanks
-Ursprüngliche Nachricht-
Von: Christian Maeder [mailto:christian.mae...@dfki.de]
Gesendet: Montag, 7. März 2011 14:18
An: Hauschild, Klaus (EXT)
Cc: haskell-cafe@haskell.org
Betreff: Re: Overlaping Parsec rules
Am 07.03.2011 13:48, schrieb Hauschild, Klaus (EXT):
Thanks Christian,
I adapted the keyword parser and now n - negi does not occur.
But there are still other problems to solve. If I activate the parseFunction
the parser will answer to fact.gml unexpected end of input, expecting space
or }.
Your redefinition of spaces (= skipMany1 space) is problematic and:
parseList = sepBy parseGml' spaces
Allow for the original (optional) spaces after parseGml':
parseGml'' = liftM2 const parseGml' spaces
parseList = many parseGml''
C.
P.S. why do you call? many (noneOf )
manyTill anyChar newline
or just: many (noneOf \n)
(a trailing newline will be skipped by spaces)
Any ideas?
-Ursprüngliche Nachricht-
Von: Christian Maeder [mailto:christian.mae...@dfki.de]
Gesendet: Montag, 7. März 2011 12:23
An: Hauschild, Klaus (EXT)
Cc: haskell-cafe@haskell.org
Betreff: Re: Overlaping Parsec rules
You should parse keywords using:
keyword s = try (string s) notFollowedBy (letter | digit)
C.
Am 07.03.2011 11:34, schrieb Hauschild, Klaus (EXT):
Hi,
to solve this ICFP task _http://www.cs.cornell.edu/icfp/task.htm_ I'm
currnetly working on the parser. With the hint from Thu (reading Phillip
Wadlers monadic parser paper) and consulting
_http://en.wikibooks.org/wiki/Write_Yourself_a_Scheme_in_48_Hours/Parsing_
I produce a first working version of the parser.
After this great moment I completed the token definition and near all
parsing rules. For the complete code have a look at
_http://code.google.com/p/hgmltracer/source/browse/#svn%2Ftrunk%2FhGmlTracer_
data GmlToken =
-- structures
FunctionToken TokenSequence |
ArrayToken TokenSequence|
-- control operators
ApplyToken |
IfToken |
-- number operators
AddiToken |
AddfToken |
ACosToken |
ASinToken |
ClampfToken |
CosToken|
DiviToken |
DivfToken |
EqiToken|
EqfToken|
FloorToken |
FracToken |
LessiToken |
LessfToken |
ModiToken |
MuliToken |
MulfToken |
NegiToken |
NegfToken |
ToRealToken |
SinToken|
SqrtToken |
SubiToken |
SubfToken |
-- points
GetXToken |
GetYToken |
GetZToken |
PointToken |
-- arrays
GetToken|
Re: [Haskell-cafe] Overlaping Parsec rules
Am 08.03.2011 13:35, schrieb Hauschild, Klaus (EXT):
Hi Christian,
Thank you for your help. Now the current version of Parse.hs
(http://code.google.com/p/hgmltracer/source/browse/trunk/hGmlTracer/src/Gml/Parse.hs)
works well for the test file fact.gml.
spaces
char end
The idea is to call spaces _after_ every token. So the keyword parser
should be extended by spaces and also the number, char, string,
binder and identifier parsers. Rather than using 'noneOf ]}\n\t' I
would precisely define the identifier letters.
isIdChar :: Char - Bool
isIdChar c = isLetter c || isDigit c ||
and use satisfy isIdChar also in keyword's notFollowedBy.
Now the last thing is parsing the different numbers (integer and float). If
have a rule for parsing integers (parseInteger = liftM (IntToken . read) $
many1 digit) but if have currently no idea how to handle floats.
Look inside
http://hackage.haskell.org/packages/archive/parsec2/1.0.0/doc/html/src/Text-ParserCombinators-Parsec-Token.html
under floating and copy and adjust the code for you.
C.
-Ursprüngliche Nachricht-
Von: Christian Maeder [mailto:christian.mae...@dfki.de]
Gesendet: Dienstag, 8. März 2011 13:26
An: Hauschild, Klaus (EXT)
Cc: haskell-cafe@haskell.org
Betreff: Re: Overlaping Parsec rules
Am 08.03.2011 12:30, schrieb Hauschild, Klaus (EXT):
Hi Christian,
my version of parseList works currently strange.
The input {2\n2} will be parsed fine, but something like { } or so fails
with 'expecting space or }'.
Also } (and ], etc.) should be excluded as identifier letters.
} is the second identifier in { }. (The first one is empty.)
C.
The redefinition of space is not necessary, it was copied from another
tutorial code. How I write a version of parseGml that get gml token
separated by any white space (space, tab, newline)?
Thanks
-Ursprüngliche Nachricht-
Von: Christian Maeder [mailto:christian.mae...@dfki.de]
Gesendet: Montag, 7. März 2011 14:18
An: Hauschild, Klaus (EXT)
Cc: haskell-cafe@haskell.org
Betreff: Re: Overlaping Parsec rules
Am 07.03.2011 13:48, schrieb Hauschild, Klaus (EXT):
Thanks Christian,
I adapted the keyword parser and now n - negi does not occur.
But there are still other problems to solve. If I activate the
parseFunction the parser will answer to fact.gml unexpected end of input,
expecting space or }.
Your redefinition of spaces (= skipMany1 space) is problematic and:
parseList = sepBy parseGml' spaces
Allow for the original (optional) spaces after parseGml':
parseGml'' = liftM2 const parseGml' spaces
parseList = many parseGml''
C.
P.S. why do you call? many (noneOf )
manyTill anyChar newline
or just: many (noneOf \n)
(a trailing newline will be skipped by spaces)
Any ideas?
-Ursprüngliche Nachricht-
Von: Christian Maeder [mailto:christian.mae...@dfki.de]
Gesendet: Montag, 7. März 2011 12:23
An: Hauschild, Klaus (EXT)
Cc: haskell-cafe@haskell.org
Betreff: Re: Overlaping Parsec rules
You should parse keywords using:
keyword s = try (string s) notFollowedBy (letter | digit)
C.
Am 07.03.2011 11:34, schrieb Hauschild, Klaus (EXT):
Hi,
to solve this ICFP task _http://www.cs.cornell.edu/icfp/task.htm_ I'm
currnetly working on the parser. With the hint from Thu (reading Phillip
Wadlers monadic parser paper) and consulting
_http://en.wikibooks.org/wiki/Write_Yourself_a_Scheme_in_48_Hours/Parsing_
I produce a first working version of the parser.
After this great moment I completed the token definition and near all
parsing rules. For the complete code have a look at
_http://code.google.com/p/hgmltracer/source/browse/#svn%2Ftrunk%2FhGmlTracer_
data GmlToken =
-- structures
FunctionToken TokenSequence |
ArrayToken TokenSequence|
-- control operators
ApplyToken |
IfToken |
-- number operators
AddiToken |
AddfToken |
ACosToken |
ASinToken |
ClampfToken |
CosToken|
DiviToken |
DivfToken |
EqiToken|
EqfToken|
FloorToken |
FracToken |
LessiToken |
LessfToken |
ModiToken |
MuliToken |
Re: [Haskell-cafe] makeTokenParser + LanguageDef
Hi Klaus, for what it's worth, you might want to consider using this package instead of Parsec: http://hackage.haskell.org/package/BNFC Take care, Peter ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Error recovery in Happy
Hey guys, I was wondering if there were possiblities to ignore certain errors during parsing. I tried using the error token, but that didn't seem to work. I looked at the following topic http://haskell.1045720.n5.nabble.com/Error-detection-in-GLR-Happy-grammar-td3083740.html For my parser I need to be able to parse a certain token at any place, but only in some places it is part of a rule. In other cases this token should be ignored after which the parser just procedes to the next token. Is this possible with Happy? Should I use the monadic parser to achieve this? More concretely, I have tokenized some sourcecode which contains comments, these should be ignored except when they are located above a function, in which case I want them to parse. Any ideas about this issue are greatly appreciated! Thanks, Tom ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] makeTokenParser + LanguageDef
The tutorial here: http://legacy.cs.uu.nl/daan/download/parsec/parsec.html#Lexical analysis http://legacy.cs.uu.nl/daan/download/parsec/parsec.html#Lexical analysisis for parsec 2, but it's still quite relevant. - Job On Tue, Mar 8, 2011 at 6:22 AM, Hauschild, Klaus (EXT) klaus.hauschild@siemens.com wrote: Hi Haskellers, is there a fine tutorial for building a parser with parsecs (3.*) makeTokenParser and LanguageDef stuff? Klaus ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] ANN: theoremquest-0.0.0
I am curious -- how easy is it to use theoremquest for playing with equational theories? Let me turn the question around: How easy is it to play with equational theories in HOL Light? Because this is the planed basis for TheoremQuest. -Tom ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Error recovery in Happy
I'd join comments in with tokens so each token has a comment - possibly the empty string, then the parser can decide what to do with the comment part of token - e.g retaining it for functions, ignoring it for everything else. You may have to write a two-pass lexer to do this. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Error recovery in Happy
By the way - my last answer was for the second part of the question. For error handling - Doaitse Swierstra's UU-Parsing is a combinator parsing library with some flexibility for error recovery. For an LR parser like Happy adding extra error handling cases to the productions in your grammar is the main tool you have. On 8 March 2011 15:54, Stephen Tetley stephen.tet...@gmail.com wrote: I'd join comments in with tokens so each token has a comment - possibly the empty string, then the parser can decide what to do with the comment part of token - e.g retaining it for functions, ignoring it for everything else. You may have to write a two-pass lexer to do this. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] ANN: theoremquest-0.0.0
On Mar 8, 8:20 pm, Tom Hawkins tomahawk...@gmail.com wrote: I am curious -- how easy is it to use theoremquest for playing with equational theories? Let me turn the question around: How easy is it to play with equational theories in HOL Light? Because this is the planed basis for TheoremQuest. Dunno... I am far from being a theorem-prover buff/expert :-) I know of Dijkstra-Scholten logic -- not as a formal logician but as a math teacher. But anyhow that (HOL) gives me some context and sense of direction -- Thanks. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Error recovery in Happy
That two-pass lexer sounds like a good idea. I actually want to keep the happy parser if possible, can you elaborate on adding extra error handling cases for production rules? Do you mean I have to add a line for comments on possible places where they can occur? Thanks ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Error recovery in Happy
Hi Tom
Here's how I'd do comment annotation in the Parser:
type Comment = String
type Identifier = String
I suspect data carrying tokens need to pair the data and the comment
so Happy can treat them as a positional reference e.g. $1
data Token =
TK_identifier (Identifier,Comment)
| TK_kywd_module Comment
| ...
Productions now have to use smart constructors:
module:: { Module }
: '%module' mname defs
{ mkModule $1 $2 $3 }
data Module = Module { mod_comment :: Comment
, mod_name:: String
, mod_body:: [Def]
}
The 'smart' constructor takes the comment before the module
delacration, any comment between the module start token and the module
name is ignored...
mkModule :: Comment - (String,Comment) - [Def] - Module
mkModule outer_comment (mname, _) defs =
Module outer_comment mname defs
As for error handling, the strategy is to add error handling
productions after good productions.
Now module can handle a missing module name:
module:: { Module }
: '%module' mname defs
{ mkModule $1 $2 $3 }
: ''%module' defs
{ badModule $1 $2 }
badModule :: Comment [Def] - Module
badModule outer_comment defs = Module outer_comment fake_name defs
where
fake_name = ERR - parser error reading module name
Ideally the smart constructors should be in a monad that supports
error logging like Writer.
As you can see this isn't a great way of doing things but I'm not sure
you have any other options. Personally I'd see if I could live with
first fail instead.
Best wishes
Stephen
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Re: [Haskell-cafe] Haskell IDE
On 07/03/2011 04:39 PM, Daniel Fischer wrote: That sounds nice, so I thought I'd try out leksah again. Unfortunately, the dependencies rule out GHC-7 Maybe someone could try relaxing the bounds and build it with GHC-7, and - if it works - upload a new version? (I could try if I get a go-ahead from Hamish or Jürgen) I couldn't get it to build either. So I just grabbed the Windows binary from the homepage and used that. Worked just fine... (Not sure that they have binaries for platforms that aren't Windows though. Can't remember off the top of my head.) ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Haskell Platform 2011.2
On 06/03/2011 11:46 AM, Andrew Coppin wrote: On 06/03/2011 01:22 AM, Don Stewart wrote: P.S. you can help by testing the installers, and reporting issues on the HP trac and mailing list. The candidate installers are here: http://code.galois.com/darcs/haskell-platform/download-website/ Is there some way to navigate to this page from the HP homepage? Seriously, if you want people to test it, having this fact more clearly visible seems like a good idea. (In particular, I have access to Windows systems I can test on, which is apparently rare around here, but until this email I had no idea that a release candidate was even available...) ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] have anyone tried GHC 7.0.2
ghc-pkg list returns these:
/usr/local/lib/ghc-7.0.2/package.conf.d:
Cabal-1.10.1.0
array-0.3.0.2
base-4.3.1.0
bin-package-db-0.0.0.0
bytestring-0.9.1.10
containers-0.4.0.0
directory-1.1.0.0
extensible-exceptions-0.1.1.2
ffi-1.0
filepath-1.2.0.0
(ghc-7.0.2)
(ghc-binary-0.5.0.2)
ghc-prim-0.2.0.0
(haskell2010-1.0.0.0)
haskell98-1.1.0.1
hpc-0.5.0.6
integer-gmp-0.2.0.3
old-locale-1.0.0.2
old-time-1.0.0.6
pretty-1.0.1.2
process-1.0.1.5
random-1.0.0.3
rts-1.0
template-haskell-2.5.0.0
time-1.2.0.3
unix-2.4.2.0
/home/qi/.ghc/i386-linux-7.0.2/package.conf.d:
HTTP-4000.1.1
QuickCheck-2.4.0.1
X11-1.5.0.0
X11-xft-0.3
binary-0.5.0.2
containers-0.3.0.0
cpphs-1.11
directory-1.1.0.0
filepath-1.1.0.4
haskell98-1.1.0.1
hinotify-0.3.1
hscolour-1.17
language-c-0.3.2.1
mtl-1.1.1.1
mtl-2.0.1.0
{network-2.2.1.10}
network-2.3.0.2
parsec-2.1.0.1
parsec-3.1.1
primitive-0.3.1
process-1.0.1.5
stm-2.2.0.1
storable-complex-0.2.1
syb-0.3
transformers-0.2.2.0
uniplate-1.6
utf8-string-0.3.6
vector-0.7.0.1
xmonad-0.9.2
xmonad-contrib-0.9.2
zlib-0.5.3.1
ghc-pkg check returns this:
There are problems in package network-2.2.1.10:
dependency parsec-3.1.1-583092e3fd1a17b79365b197467a185d doesn't exist
The following packages are broken, either because they have a problem
listed above, or because they depend on a broken package.
network-2.2.1.10
I installed parsec and network via cabal. Do you know how can I remove
network-2.2.1.10 that is not needed because a higher version exists.
Should I delete anything under ~/.ghc and ~/.cabal, and reinstall ghc
and cabal-install, and those pacakges installed before using cabal?
Thanks for your link of the Haskell-platform. I will wait for the
official release and hope it will be soon.
Christian Maeder christian.mae...@dfki.de writes:
What does ghc-pkg list and ghc-pkg check say?
Cabal-1.10.1.0, directory-1.1.0.0 and process-1.0.1.5 should be there
after installation of GHC 7.0.2. (I've actually installed
cabal-install-0.10.0 using an older cabal, but that does not work on
macs and may not be the recommended way.)
I think I've used
http://www.galois.com/~dons/code/2011.2.0.0/haskell-platform-2011.2.0.0.tar.gz
from http://www.galois.com/~dons/code/2011.2.0.0/, but they are not
official yet.
C.
Am 08.03.2011 19:20, schrieb Qi Qi:
Hi,
After I installed GHC 7.0.2 and cabal-install 0.10.0 using Cabal library
1.10.1, I found that some package failed to install. For example like
Happy, I got the following error:
cabal install happy
Resolving dependencies...
command line: cannot satisfy -package Cabal-1.10.1.0:
Cabal-1.10.1.0-64e8f05722ea5bbdf07df2e5a3491105 is unusable due to
missing or recursive dependencies:
directory-1.1.0.0-85d1d0f9d96dffdacf64f3cc6fba6f2f
process-1.0.1.5-4cab1bf0666275ac101dd48c7565b64c
(use -v for more information)
cabal: Error: some packages failed to install:
happy-1.18.6 failed during the configure step. The exception was:
ExitFailure 1
Besides happy package, some other packages like ghc-mod, hmatrix also
failed to install. Does anyone else have the same issue after installed
ghc 7.0.2?
By the way, does anyone hear anything about Haskell-platform 2011.2 ?
Thanks!
--
Qi Qi
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[Haskell-cafe] Tagless interpreter, expression problem and zipper
Hello everyone,
I am stuck rewriting some code in the tagless style. My problem can be
thought of as an interpreter for a very simple language:
data Exp = Lit Integer
| Add Exp Exp
| Mul Exp Exp
deriving (Show)
But some complexity is added by the fact that my interpreter also
needs to know the context in which literals appear in an
expression. So given the example
t1 :: Exp
t1 = (Lit 3 `Add` Lit 4) `Mul` Lit 2
I want to have access to the fact that the literal 3 appears on
the left side of an addition. Therefore I created a type:
data Ctx = Empty
| AddL Exp Ctx
| AddR Exp Ctx
| MulL Exp Ctx
| MulR Exp Ctx
deriving (Show)
This is almost a zipper over the Exp type. I left out a context for
literals themselves because it wasn't necessary. Now I can create a
simple evaluation function:
eval :: (a - a - a)
- (a - a - a)
- (Integer - Ctx - a)
- Exp
- a
eval add mul lit = go Empty
where
go ctx (Lit n) = lit n ctx
go ctx (Add x y) = let x' = go (AddL y ctx) x
y' = go (AddR x ctx) y
in x' `add` y'
go ctx (Mul x y) = let x' = go (MulL y ctx) x
y' = go (MulR x ctx) y
in x' `mul` y'
This function can evaluate an expression to any type 'a', but it needs
some additional functions to accomplish that: add, mul and lit. Notice
how the 'lit' function has access to a literal's context. To interpret
an Exp as an Integer I use:
evalInt :: Exp - Integer
evalInt = eval (+) (*) const
Or as a String:
evalStr1 :: Exp - String
evalStr1 = eval addStr mulStr (const . show)
addStr x y = ( ++ x ++ + ++ y ++ )
mulStr x y = ( ++ x ++ * ++ y ++ )
Or a silly example which uses the context:
evalStr2 :: Exp - String
evalStr2 = eval addStr mulStr lit
where
lit _ (AddL (Lit 4) (MulL _ _)) = Foo!
lit n _ = show n
The silly example replaces a literal with Foo! if it appears on the
left side of an addition with 4, and the whole addition is the left
side of a multiplication, like in (x + 4) * ?.
All of this works. But I want to be able to add additional
constructors to the Exp language without changing existing code. This
looks like the expression problem.
Ignoring the zipper-like context I came up with the following:
First define the language:
class Lit a where lit :: Integer - a
class Add a where add :: a - a - a
class Mul a where mul :: a - a - a
Integer interpreter:
instance Lit Integer where lit = fromInteger
instance Add Integer where add = (+)
instance Mul Integer where mul = (*)
String interpreter, using a newtype so I don't need
TypeSynonymInstances:
newtype Str = Str {unS :: String}
instance Show Str where show = show . unS
instance Lit Str where lit = Str . show
instance Add Str where add x y = Str $ addStr (unS x) (unS y)
instance Mul Str where mul x y = Str $ mulStr (unS x) (unS y)
Same example expression, now polymorphic:
t1 :: (Lit a, Add a, Mul a) = a
t1 = (lit 3 `add` lit 4) `mul` lit 2
This expression can now be interpreted in multiple ways:
t1 :: Integer
14
t1 :: Str
((3 + 4) * 2)
This solves the expression problem. I can add new structures to my
language in other modules without having to change existing code. The
necessary parts are mentioned in the type constraint (Lit a, Add a,
Mul a).
But I lost the power of the context! How do I get it back?
Attached are the two approaches, WithTags.hs and Tagless.hs (but
without context).
Any help would be greatly appreciated!
module WithTags where
data Exp = Lit Integer
| Add Exp Exp
| Mul Exp Exp
deriving (Show)
data Ctx = Empty
| AddL Exp Ctx
| AddR Exp Ctx
| MulL Exp Ctx
| MulR Exp Ctx
deriving (Show)
eval :: (a - a - a)
- (a - a - a)
- (Integer - Ctx - a)
- Exp
- a
eval add mul lit = go Empty
where
go ctx (Lit n) = lit n ctx
go ctx (Add x y) = let x' = go (AddL y ctx) x
y' = go (AddR x ctx) y
in x' `add` y'
go ctx (Mul x y) = let x' = go (MulL y ctx) x
y' = go (MulR x ctx) y
in x' `mul` y'
evalInt :: Exp - Integer
evalInt = eval (+) (*) const
addStr x y = ( ++ x ++ + ++ y ++ )
mulStr x y = ( ++ x ++ * ++ y ++ )
evalStr1 :: Exp - String
evalStr1 = eval addStr mulStr (const . show)
evalStr2 :: Exp - String
evalStr2 = eval addStr mulStr lit
where
lit _ (AddL (Lit 4) (MulL _ _)) = Foo!
lit n _ = show n
t1 :: Exp
t1 = (Lit 3 `Add` Lit 4) `Mul` Lit 2
module Tagless where
class Lit a where lit :: Integer - a
class Add a where add :: a - a - a
class Mul a where mul :: a - a - a
instance Lit Integer where lit = fromInteger
instance Add Integer where add = (+)
instance Mul Integer where mul = (*)
-- Newtype so I
Re: [Haskell-cafe] Haskell IDE
On Tuesday 08 March 2011 21:16:33, Andrew Coppin wrote: On 07/03/2011 04:39 PM, Daniel Fischer wrote: That sounds nice, so I thought I'd try out leksah again. Unfortunately, the dependencies rule out GHC-7 Maybe someone could try relaxing the bounds and build it with GHC-7, and - if it works - upload a new version? (I could try if I get a go-ahead from Hamish or Jürgen) I couldn't get it to build either. So I just grabbed the Windows binary from the homepage and used that. Worked just fine... (Not sure that they have binaries for platforms that aren't Windows though. Can't remember off the top of my head.) From what I remember, Mac, Fedora and Arch linux. I guess there's a chance the Fedora RPMs work on openSUSE, but I won't try. I'll wait for the next version on hackage. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Haskell Platform 2011.2
We have plenty of testers on the haskell-platform@ list. If you're interested, you can join there to discuss results. By definition the test installers are not yet ready for haskell-cafe@ consumption. -- Don On Tue, Mar 8, 2011 at 12:17 PM, Andrew Coppin andrewcop...@btinternet.com wrote: On 06/03/2011 11:46 AM, Andrew Coppin wrote: On 06/03/2011 01:22 AM, Don Stewart wrote: P.S. you can help by testing the installers, and reporting issues on the HP trac and mailing list. The candidate installers are here: http://code.galois.com/darcs/haskell-platform/download-website/ Is there some way to navigate to this page from the HP homepage? Seriously, if you want people to test it, having this fact more clearly visible seems like a good idea. (In particular, I have access to Windows systems I can test on, which is apparently rare around here, but until this email I had no idea that a release candidate was even available...) ___ 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] have anyone tried GHC 7.0.2
On Wednesday 09 March 2011 11:42:48, Qi Qi wrote: ghc-pkg check returns this: There are problems in package network-2.2.1.10: dependency parsec-3.1.1-583092e3fd1a17b79365b197467a185d doesn't exist Seems parsec-3.1.1 was rebuilt after network-2.2.1.10 was installed. Any idea what package caused that? The following packages are broken, either because they have a problem listed above, or because they depend on a broken package. network-2.2.1.10 I installed parsec and network via cabal. Do you know how can I remove network-2.2.1.10 that is not needed because a higher version exists. Try $ ghc-pkg unregister network-2.2.1.10 If ghc-pkg says that would break other packages (it shouldn't, if it would, those should have been reported too), you could unregister them first (or use --force) (and reinstall them afterwards). Should I delete anything under ~/.ghc and ~/.cabal, and reinstall ghc and cabal-install, and those pacakges installed before using cabal? Not as a first measure, while breakage is small, ghc-pkg unregister tends to be less work. Only if you have lots of breakage would I recommend deleting the local package db. Thanks for your link of the Haskell-platform. I will wait for the official release and hope it will be soon. Should be only a couple of days, iirc. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Haskell Platform 2011.2
On 08/03/2011 08:57 PM, Don Stewart wrote: We have plenty of testers on the haskell-platform@ list. If you're interested, you can join there to discuss results. By definition the test installers are not yet ready for haskell-cafe@ consumption. Oh, right. There's a mailing list? I wasn't aware of that. I'll go take a look... ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] some problem with Cabal
Hi, When I tried the haskell platform 2011.2 source, from here http://code.galois.com/darcs/haskell-platform/download-website/linux.html . Configuration passed successfully. But when making, it gives the following error: scripts/build.sh ** Scanning system for any installed Haskell Platform components... Found:None. New packages to install: None! All done. ** Building /usr/local/bin/ghc --make Setup -o Setup -package Cabal-1.10.1.0 command line: cannot satisfy -package Cabal-1.10.1.0: Cabal-1.10.1.0-64e8f05722ea5bbdf07df2e5a3491105 is unusable due to missing or recursive dependencies: directory-1.1.0.0-85d1d0f9d96dffdacf64f3cc6fba6f2f process-1.0.1.5-4cab1bf0666275ac101dd48c7565b64c (use -v for more information) Error: Compiling the Setup script failed make: *** [build.stamp] Error 2 I think this is the same problem as I got during installing some other packages via cabal such as hmatrix, ghc-mod, happy and etc. Does anyone have any idea about how to solve it? Thanks! -- Qi Qi ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] have anyone tried GHC 7.0.2
Thank you! I fixed the broken package, network-2.2.1.10 by manually removing it locally and recache the ghc's package cache by running ghc-pkg recache. Thanks though for the unregister option. Now ghc-pkg check doesn't return any broken packages. But Cabal seems still got problem. I got the same cabal problem when I tried to test with the haskell-platform 2011-2. I have post another with that regard. -- View this message in context: http://haskell.1045720.n5.nabble.com/have-anyone-tried-GHC-7-0-2-tp3413510p3414675.html Sent from the Haskell - Haskell-Cafe mailing list archive at Nabble.com. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] some problem with Cabal
On Wednesday 09 March 2011 12:16:30, Qi Qi wrote: I think this is the same problem as I got during installing some other packages via cabal such as hmatrix, ghc-mod, happy and etc. Does anyone have any idea about how to solve it? I think it may be a problem with your GHC. I have no problems cabal install'ing packages using $ cabal --version cabal-install version 0.10.0 using version 1.10.1.0 of the Cabal library $ ghc --version The Glorious Glasgow Haskell Compilation System, version 7.0.2 Does compiling a simple module using the Cabal library work? (for example module Main (main) where import Distribution.Simple.Setup main :: IO () main = print defaultGlobalFlags ) If your Cabal package is really unusable, that should break too (but then, why doesn't ghc-pkg check report it as broken?). Re-installing Cabal would be an option then. If it works, on the other hand, the problem may be with your cabal and re- installing that may be worth a try. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Error recovery in Happy
Alright thanks for your comprehensive answer! I think I got something to
work with :)
Cheers,
Tom
On Tue, Mar 8, 2011 at 8:09 PM, Stephen Tetley stephen.tet...@gmail.comwrote:
Hi Tom
Here's how I'd do comment annotation in the Parser:
type Comment = String
type Identifier = String
I suspect data carrying tokens need to pair the data and the comment
so Happy can treat them as a positional reference e.g. $1
data Token =
TK_identifier (Identifier,Comment)
| TK_kywd_module Comment
| ...
Productions now have to use smart constructors:
module:: { Module }
: '%module' mname defs
{ mkModule $1 $2 $3 }
data Module = Module { mod_comment :: Comment
, mod_name:: String
, mod_body:: [Def]
}
The 'smart' constructor takes the comment before the module
delacration, any comment between the module start token and the module
name is ignored...
mkModule :: Comment - (String,Comment) - [Def] - Module
mkModule outer_comment (mname, _) defs =
Module outer_comment mname defs
As for error handling, the strategy is to add error handling
productions after good productions.
Now module can handle a missing module name:
module:: { Module }
: '%module' mname defs
{ mkModule $1 $2 $3 }
: ''%module' defs
{ badModule $1 $2 }
badModule :: Comment [Def] - Module
badModule outer_comment defs = Module outer_comment fake_name defs
where
fake_name = ERR - parser error reading module name
Ideally the smart constructors should be in a monad that supports
error logging like Writer.
As you can see this isn't a great way of doing things but I'm not sure
you have any other options. Personally I'd see if I could live with
first fail instead.
Best wishes
Stephen
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Re: [Haskell-cafe] have anyone tried GHC 7.0.2
The problem is solved! I found out that both global and local package db get directory-1.1.0.0 and process-1.0.1.5. I unregistered them and other caused broken packages in the local package db. Then I successfully installed back hmatrix, ghc-mod, happy and etc. It seems that xmobar will install directory-1.1.0.0 again in the local package db. Thank you all who replied this threading! -- View this message in context: http://haskell.1045720.n5.nabble.com/have-anyone-tried-GHC-7-0-2-tp3413510p3414820.html Sent from the Haskell - Haskell-Cafe mailing list archive at Nabble.com. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] some problem with Cabal
Thank you, Daniel. The problem is solved! I found out that both global and local package db get directory-1.1.0.0 and process-1.0.1.5. I unregistered them and other caused broken packages in the local package db. Then I successfully installed back hmatrix, ghc-mod, happy and etc. It seems that xmobar will install directory-1.1.0.0 again in the local package db. Did you succeed in installing haddock 2.9? Mine got some syntax oriented error duing cabal install haddock. But it's fine. Daniel Fischer wrote: On Wednesday 09 March 2011 12:16:30, Qi Qi wrote: I think this is the same problem as I got during installing some other packages via cabal such as hmatrix, ghc-mod, happy and etc. Does anyone have any idea about how to solve it? I think it may be a problem with your GHC. I have no problems cabal install'ing packages using $ cabal --version cabal-install version 0.10.0 using version 1.10.1.0 of the Cabal library $ ghc --version The Glorious Glasgow Haskell Compilation System, version 7.0.2 Does compiling a simple module using the Cabal library work? (for example module Main (main) where import Distribution.Simple.Setup main :: IO () main = print defaultGlobalFlags ) If your Cabal package is really unusable, that should break too (but then, why doesn't ghc-pkg check report it as broken?). Re-installing Cabal would be an option then. If it works, on the other hand, the problem may be with your cabal and re- installing that may be worth a try. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe -- View this message in context: http://haskell.1045720.n5.nabble.com/some-problem-with-Cabal-tp3414662p3414823.html Sent from the Haskell - Haskell-Cafe mailing list archive at Nabble.com. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] some problem with Cabal
On Wednesday 09 March 2011 00:34:39, qiqi wrote: The problem is solved! I found out that both global and local package db get directory-1.1.0.0 and process-1.0.1.5. I unregistered them and other caused broken packages in the local package db. D'oh, I should've seen that. Then I successfully installed back hmatrix, ghc-mod, happy and etc. It seems that xmobar will install directory-1.1.0.0 again in the local package db. That's not good. And it doesn't seem to do that here: $ cabal install xmobar --dry-run Resolving dependencies... In order, the following would be installed (use -v for more details): stm-2.2.0.1 syb-0.3 X11-1.5.0.0 utf8-string-0.3.6 xmobar-0.12 What does $ cabal install xmobar --dry-run -v3 say for you about directory? Did you succeed in installing haddock 2.9? That was built with the compiler (I built from source), no problems. $ haddock --version Haddock version 2.9.2, (c) Simon Marlow 2006 Ported to use the GHC API by David Waern 2006-2008 Mine got some syntax oriented error duing cabal install haddock. But it's fine. The same as http://haskell.org/pipermail/haskell-cafe/2011-March/089902.html ? I don't know if that's been solved. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] some problem with Cabal
This is fixed in the new release of cabal-install ( I think) so we're rolling new installers. Discussion around the installers is taking place on the haskell-platform list. -- Don On Wed, Mar 9, 2011 at 3:16 AM, Qi Qi qiqi...@gmail.com wrote: Hi, When I tried the haskell platform 2011.2 source, from here http://code.galois.com/darcs/haskell-platform/download-website/linux.html . Configuration passed successfully. But when making, it gives the following error: scripts/build.sh ** Scanning system for any installed Haskell Platform components... Found:None. New packages to install: None! All done. ** Building /usr/local/bin/ghc --make Setup -o Setup -package Cabal-1.10.1.0 command line: cannot satisfy -package Cabal-1.10.1.0: Cabal-1.10.1.0-64e8f05722ea5bbdf07df2e5a3491105 is unusable due to missing or recursive dependencies: directory-1.1.0.0-85d1d0f9d96dffdacf64f3cc6fba6f2f process-1.0.1.5-4cab1bf0666275ac101dd48c7565b64c (use -v for more information) Error: Compiling the Setup script failed make: *** [build.stamp] Error 2 I think this is the same problem as I got during installing some other packages via cabal such as hmatrix, ghc-mod, happy and etc. Does anyone have any idea about how to solve it? Thanks! -- Qi Qi ___ 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] some problem with Cabal
I used cabal install xmobar --flags=all_extensions . Is it true that every package installed from hackage should not install any package, which already exists in the global with the same version number , in the local db? Daniel Fischer wrote: On Wednesday 09 March 2011 00:34:39, qiqi wrote: The problem is solved! I found out that both global and local package db get directory-1.1.0.0 and process-1.0.1.5. I unregistered them and other caused broken packages in the local package db. D'oh, I should've seen that. Then I successfully installed back hmatrix, ghc-mod, happy and etc. It seems that xmobar will install directory-1.1.0.0 again in the local package db. That's not good. And it doesn't seem to do that here: $ cabal install xmobar --dry-run Resolving dependencies... In order, the following would be installed (use -v for more details): stm-2.2.0.1 syb-0.3 X11-1.5.0.0 utf8-string-0.3.6 xmobar-0.12 What does $ cabal install xmobar --dry-run -v3 say for you about directory? Did you succeed in installing haddock 2.9? That was built with the compiler (I built from source), no problems. $ haddock --version Haddock version 2.9.2, (c) Simon Marlow 2006 Ported to use the GHC API by David Waern 2006-2008 Mine got some syntax oriented error duing cabal install haddock. But it's fine. The same as http://haskell.org/pipermail/haskell-cafe/2011-March/089902.html ? I don't know if that's been solved. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe -- View this message in context: http://haskell.1045720.n5.nabble.com/some-problem-with-Cabal-tp3414662p3414931.html Sent from the Haskell - Haskell-Cafe mailing list archive at Nabble.com. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] some problem with Cabal
On Wednesday 09 March 2011 02:51:35, qiqi wrote: I used cabal install xmobar --flags=all_extensions . Whoa: In order, the following would be installed: containers-0.3.0.0 (new version) filepath-1.1.0.4 (new version) directory-1.1.0.0 (reinstall) changes: filepath-1.2.0.0 - 1.1.0.4 hinotify-0.3.1 (new package) mtl-1.1.1.1 (new version) network-2.2.1.10 (new version) process-1.0.1.5 (reinstall) changes: filepath-1.2.0.0 - 1.1.0.4 stm-2.2.0.1 (new package) syb-0.3 (new package) X11-1.5.0.0 (new package) time-1.1.4 (new version) random-1.0.0.3 (reinstall) changes: time-1.2.0.3 - 1.1.4 haskell98-1.1.0.1 (reinstall) utf8-string-0.3.6 (new package) X11-xft-0.3 (new package) libmpd-0.5.0 (new package) xmobar-0.12 (new package) I haven't looked further, but libmpd is at least partially responsible, it depends on filepath 1.2, time 1.2 and a couple other old packages. Is it true that every package installed from hackage should not install any package, which already exists in the global with the same version number , in the local db? Generally, it shouldn't (and doesn't), but here some packages have to be reinstalled because they have to be built against different dependencies. I'd prefer cabal install to refuse here (overridable with a --force flag) because reinstalling boot libs (containers, filepath, directory, process, time) tends to be a bad idea. However, xmobar is an executable and no library, so if you unregister the packages (from the user db!) after installing before they can cause trouble, you should be fine (but no guarantees). ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] some problem with Cabal
Daniel Fischer wrote: On Wednesday 09 March 2011 02:51:35, qiqi wrote: I used cabal install xmobar --flags=all_extensions . Whoa: In order, the following would be installed: containers-0.3.0.0 (new version) filepath-1.1.0.4 (new version) directory-1.1.0.0 (reinstall) changes: filepath-1.2.0.0 - 1.1.0.4 hinotify-0.3.1 (new package) mtl-1.1.1.1 (new version) network-2.2.1.10 (new version) process-1.0.1.5 (reinstall) changes: filepath-1.2.0.0 - 1.1.0.4 stm-2.2.0.1 (new package) syb-0.3 (new package) X11-1.5.0.0 (new package) time-1.1.4 (new version) random-1.0.0.3 (reinstall) changes: time-1.2.0.3 - 1.1.4 haskell98-1.1.0.1 (reinstall) utf8-string-0.3.6 (new package) X11-xft-0.3 (new package) libmpd-0.5.0 (new package) xmobar-0.12 (new package) I haven't looked further, but libmpd is at least partially responsible, it depends on filepath 1.2, time 1.2 and a couple other old packages. Is it true that every package installed from hackage should not install any package, which already exists in the global with the same version number , in the local db? Generally, it shouldn't (and doesn't), but here some packages have to be reinstalled because they have to be built against different dependencies. I'd prefer cabal install to refuse here (overridable with a --force flag) because reinstalling boot libs (containers, filepath, directory, process, time) tends to be a bad idea. However, xmobar is an executable and no library, so if you unregister the packages (from the user db!) after installing before they can cause trouble, you should be fine (but no guarantees). This is exactly what I am doing. I unregistered those packages but kept the xmobar's executable under ~/.cabal/bin. It works fine. Thanks Daniel. I appreciate it! ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe -- View this message in context: http://haskell.1045720.n5.nabble.com/some-problem-with-Cabal-tp3414662p3414954.html Sent from the Haskell - Haskell-Cafe mailing list archive at Nabble.com. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Tagless interpreter, expression problem and zipper
2011/3/8 Roel van Dijk vandijk.r...@gmail.com:
Hello everyone,
Hello!
But I lost the power of the context! How do I get it back?
The tagless interpreters splits the interpreter code (in your case,
the 'eval' function) into multiple functions on one or more type
classes. Now, the key insight is that your interpreter is actually
not 'eval' but 'go' =), which has type 'Ctx - a' (instead of just
'a'). But you don't need to change any code that uses Lit, Add and
Mul, they work unmodified.
First of all, I'll generalize your context a bit:
data Ctx a = Empty
| AddL a (Ctx a)
| AddR a (Ctx a)
| MulL a (Ctx a)
| MulR a (Ctx a)
deriving (Show)
Now we can create a new interpreter:
newtype CtxInterpA a = CIA {unCIA :: Ctx a → a}
I'm appending A to its name because later on I'll propose another
interpreter B. The underlying type 'a' is the same 'a' from your
original 'eval' function, so we can't use 'lit' from 'Lit' type class.
So we create
class CtxLitA a where
ctxLitA :: Integer → Ctx a → a
Our interpreter's instance for 'Lit' is then simply
instance CtxLitA a ⇒ Lit (CtxInterpA a) where
lit = CIA∘ctxLitA
To get a result from 'CtxInterpA a' we just pass an empty context:
fromCtxInterpA :: CtxInterpA a → a
fromCtxInterpA x = unCIA x Empty
The 'Add' instance, however, is somewhat problematic. We need an 'a'
for our 'Ctx a', however the arguments given for 'add' are of type
'CtxInterpA a'. To get an 'a' from 'CtxInterpA a' we need, again, a
'Ctx a'.
instance Add a ⇒ Add (CtxInterpA a) where
add x y = CIA (λctx → let x' = unCIA x (AddL y' ctx)
y' = unCIA y (AddR x' ctx)
in x' `add` y')
The main problem with this instance with respect to your original
'eval' code is that in 'AddL' and 'AddR' we have y' and x', and not y
and x. So y' and x' are mutually recursive. The Mul instance is
similar.
This may or may not be what you wanted on your original problem.
Note, however, that there's a plan B. We can have different
definitions of CtxLitA and CtxInterpA, this time using 'Ctx Exp':
class CtxLitB a where
ctxLitB :: Integer → Ctx Exp → a
data CtxInterpB a = CIB {cibMake :: Ctx Exp → a
,cibExp :: Exp}
Besides our function that creates 'a's, we also keep note of the
corresponding 'Exp' and use it to create the 'Ctx Exp' without mutual
recursion:
instance CtxLitB a ⇒ Lit (CtxInterpB a) where
lit i = CIB (ctxLitB i) (lit i)
instance Add a ⇒ Add (CtxInterpB a) where
add x y = CIB (λctx → let x' = cibMake x (AddL (cibExp y) ctx)
y' = cibMake y (AddR (cibExp x) ctx)
in x' `add` y')
(add (cibExp x) (cibExp y))
The drawback of this approach should be obvious: we are tagging
everything =). So this sort of defeats the tagless interpreter
approach.
I don't know if this solves your real problem, but it may be a start
=). I'm attaching everything.
Cheers,
--
Felipe.
module Tagless where
class Lit a where lit :: Integer - a
class Add a where add :: a - a - a
class Mul a where mul :: a - a - a
instance Lit Integer where lit = fromInteger
instance Add Integer where add = (+)
instance Mul Integer where mul = (*)
-- Newtype so I don't need FlexibleInstances.
newtype Str = Str {unS :: String}
instance Show Str where show = show . unS
addStr x y = ( ++ x ++ + ++ y ++ )
mulStr x y = ( ++ x ++ * ++ y ++ )
instance Lit Str where lit = Str . show
instance Add Str where add x y = Str $ addStr (unS x) (unS y)
instance Mul Str where mul x y = Str $ mulStr (unS x) (unS y)
t1 :: (Lit a, Add a, Mul a) = a
t1 = (lit 3 `add` lit 4) `mul` lit 2
data Exp = Lit Integer
| Add Exp Exp
| Mul Exp Exp
deriving (Show)
instance Lit Exp where lit = Lit
instance Add Exp where add = Add
instance Mul Exp where mul = Mul
data Ctx a = Empty
| AddL a (Ctx a)
| AddR a (Ctx a)
| MulL a (Ctx a)
| MulR a (Ctx a)
deriving (Show)
-- First approach
-- Drawback: mutual recursion on the definition of add and mul.
class CtxLitA a where
ctxLitA :: Integer - Ctx a - a
newtype CtxInterpA a = CIA {unCIA :: Ctx a - a}
instance CtxLitA a = Lit (CtxInterpA a) where
lit = CIA . ctxLitA
instance Add a = Add (CtxInterpA a) where
add x y = CIA (\ctx - let x' = unCIA x (AddL y' ctx)
y' = unCIA y (AddR x' ctx)
in x' `add` y')
instance Mul a = Mul (CtxInterpA a) where
mul x y = CIA (\ctx - let x' = unCIA x (MulL y' ctx)
y' = unCIA y (MulR x' ctx)
in x' `mul` y')
fromCtxInterpA :: CtxInterpA a - a
fromCtxInterpA x = unCIA x Empty
-- Second approach
-- Drawback: have to maintain two representations
class CtxLitB a where
ctxLitB :: Integer - Ctx Exp - a
data CtxInterpB a
[Haskell-cafe] cabal install / upgrade (was: Re: some problem with Cabal)
Generally, it shouldn't (and doesn't), but here some packages have to be reinstalled because they have to be built against different dependencies. I'd prefer cabal install to refuse here (overridable with a --force flag) because reinstalling boot libs (containers, filepath, directory, process, time) tends to be a bad idea. Seconded! I've had my setup screwed up because some package wanted to recompile base against a tiny version bump on the random package for whatever reason. The presence of two bases with the same version, one in the ghc dir and one in /usr/local/lib proceded to screw up all kinds of things. It took a long time to figure out because I wasn't expecting two copies of base with the same version, and it somehow managed to overwrite the package file in package.conf.d so the original metadata was gone. Eventually I gave up and reinstalled ghc. And all I did was accidentally run cabal upgrade somepackage when I wanted to install a newer version of somepackage. By the time I realized it was apparently still aliased to cabal break-everything and hit ^C it was too late. And it's not like I haven't been warned away from cabal upgrade either... but it made me think, if the command is so dangerous, should it have a scarier name? ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] operations on lists with continuations
On Thu, Mar 3, 2011 at 12:33 AM, Mark Lentczner mark.lentcz...@gmail.com wrote: To make up for my total misunderstanding of what you were asking before, I hereby offer you the Plumbing module, available here: https://bitbucket.org/mtnviewmark/haskell-playground/src/2d022b576c4e/Plumbing.hs With it, I think you can construct the kinds of pipelines you describe with the composition aspects you desire: Indeed, it looks like a more thorough version of what I'm doing. I'm guessing the breaking into pairs thing would be ultimately more composable, by which I mean lead to fewer special case functions. :load Plumbing.hs [1 of 1] Compiling Plumbing ( Plumbing.hs, interpreted ) Ok, modules loaded: Plumbing. let filterUntil cond start end = (passUntil (=start) =|= pfilter cond) =+= passWhile (end) let filterUntilPlus1 cond start end = filterUntil cond start end =+= pass 1 filterUntil even 10 15 `pump` [1..] [2,4,6,8,10,11,12,13,14] filterUntilPlus1 even 10 15 `pump` [1..] [2,4,6,8,10,11,12,13,14,15] I would write the above as: let filterUntilPlus1 cond start end = Then.filter cond (=start) $ Then.takeWhile (end) $ take 1 filterUntilPlus1 even 10 15 [1..] [2,4,6,8,10,11,12,13,14,15] I think mine is less flexible but it interacts with the basic list functions more directly so it feels simpler to me. In a way it reminds me of STM, in that as long as you leave the last continuation on, it's still open and can be composed. But to get the actual result, you have to stick a non-continuation function on the end, at which point it no longer composes. I suppose that's the model for many many little DSLs though. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] operations on lists with continuations
On Wed, Mar 2, 2011 at 12:00 AM, Stephen Tetley stephen.tet...@gmail.com wrote: Maybe you've invented the ApoPrelude? If I were doing it I'd probably code them in terms of an apomorphism - unfoldr with flush. Unlike regular unfoldr which discards the final state, an apomorphism uses the final state to produce the tail of the output list. See Jeremy Gibbons paper Streaming representation-changers section 4.4. http://www.comlab.ox.ac.uk/jeremy.gibbons/publications/ Interesting, thanks for the link. Indeed it looks like a special case of a general concept someone has already gotten a fair bit of milage out of :) ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Haskell Platform 2011.2
Hi, Am Samstag, den 05.03.2011, 17:22 -0800 schrieb Don Stewart: We're currently testing the installers, with a view to announcing the release early in the week. I thought http://code.haskell.org/haskell-platform/haskell-platform.cabal was the repository for the current darcs version of the platform, but now I also find http://code.galois.com/darcs/haskell-platform/haskell-platform.cabal Which one is to be used? Greetings, Joachim -- Joachim nomeata Breitner Debian Developer nome...@debian.org | ICQ# 74513189 | GPG-Keyid: 4743206C JID: nome...@joachim-breitner.de | http://people.debian.org/~nomeata signature.asc Description: This is a digitally signed message part ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
