Re: [Haskell-cafe] ANN: new version of uu-parsinglib

2009-06-02 Thread Ross Paterson
On Mon, Jun 01, 2009 at 08:27:05PM +0200, S. Doaitse Swierstra wrote: > And rename "empty" to "fail"? You managed to confuse me since I always > use pSucceed to recognise the empty string. That would clash with the existing and widely used "fail". One could view "empty" as the parser for the em

Re: [Haskell-cafe] Trouble with types

2009-06-02 Thread wren ng thornton
Vladimir Reshetnikov wrote: Hi Daniel, Could you please explain what does mean 'monomorphic' in this context? I thought that all type variables in Haskell are implicitly universally quantified, so (a -> a) is the same type as (forall a. a -> a) At the top level (i.e. definition level), yes. Ho

Re: [Haskell-cafe] Possible Haskell Project

2009-06-02 Thread wren ng thornton
Tom Hawkins wrote: At the core, the fundamental problem is not that complicated. It's just storing and retrieving a person's various health events: checkups, prescriptions, procedures, test results, etc. The main technical challenges are database distribution and patient security. Both are fun

Re: [Haskell-cafe] Checking a value against a passed-in constructor?

2009-06-02 Thread Dan
Hi Richard, > Yeek. Why do you want to do _that_? Heh. I've got a parser and I want to check what I've parsed (it's an exercise in Write Yourself a Scheme in 48 Hours). > check (Atom _) (Atom _) = True > check (Bool _) (Bool _) = True > check __= False Yes I

[Haskell-cafe] HaL4: Haskell-Meeting in Germany, 12th June 2009

2009-06-02 Thread Janis Voigtlaender
Hi all, If you are anyway near Halle/Saale in June, be sure not to miss out on: http://iba-cg.de/hal4.html We have already close to 50 registered participants, so expect a very lively meeting. See you there? (Late registration still possible.) Ciao, Janis. -- Dr. Janis Voigtlaender http://w

Re: [Haskell-cafe] HaL4: Haskell-Meeting in Germany, 12th June 2009

2009-06-02 Thread Janis Voigtlaender
Janis Voigtlaender wrote: Hi all, If you are anyway near Halle/Saale in June, be sure not to miss out on: I meant "anywhere near", of course :-) And even if you are not anyway or anywhere near, you might still want to come just for the occasion :-) -- Dr. Janis Voigtlaender http://wwwtcs.inf

[Haskell-cafe] Compiling a windows app - embedding application icon

2009-06-02 Thread GüŸnther Schmidt
Hi all, is it possible to make ghc embedd an application icon in the .exe during the compilation process? Günther ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe

[Haskell-cafe] HXT XmlPicklers - TH Derivation

2009-06-02 Thread Max Cantor
Hi, I have developed some simple TH code to automatically derive XmlPickler instances for my types and if there is interest, I will clean it up and submit a patch. Its not complete, but is a start. Any interest? Max ___ Haskell-Cafe mailing l

[Haskell-cafe] Spam apology

2009-06-02 Thread Daniel Cook
Sorry for all the repeated messages, my e-mail client exploded. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe

Re: [Haskell-cafe] Compiling a windows app - embedding application icon

2009-06-02 Thread Bulat Ziganshin
Hello Gu?nther, Tuesday, June 2, 2009, 4:47:55 PM, you wrote: > is it possible to make ghc embedd an application icon in the .exe during > the compilation process? i've found that answer may be googled as "gcc icon": 1) create icon.rc containing one line: 100 ICON "freearc.ico" 2) compile it u

Re: [Haskell-cafe] Possible Haskell Project

2009-06-02 Thread Tom Hawkins
On Tue, Jun 2, 2009 at 12:12 AM, Antoine Latter wrote: > A good place to start is http://en.wikipedia.org/wiki/HL7 , which is a > not-for-profit organization which tries to define interfacing > standards between medical devices and medical records providers.  I > haven't worked much with their stan

Re: [Haskell-cafe] Possible Haskell Project

2009-06-02 Thread S. Doaitse Swierstra
The Dutch government has been trying to get something like this for years; parliament is asking every new minister why the promised heaven has not yet arrived, only to hear that more consultants are needed. I have been to hearings of our parliament and I can tell you such events are extreme

[Haskell-cafe] Success and one last issue with Data.Binary

2009-06-02 Thread David Leimbach
I've got the following "printHex" string as a response from a 9P server running on the Inferno Operating System. (thanks to a friendly mailing list contributor who sent a nice example of using Data.Binary) 13006500040600395032303030 This is a little endian encoded ByteString with the

Re: [Haskell-cafe] Success and one last issue with Data.Binary

2009-06-02 Thread John Van Enk
I think getRemainingLazyByteString expects at least one byte (this, perhaps, is not the appropriate behavior). You'll want to wrap your call to getRemainingLazyByteString with a call to Data.Binary.Get.remaining[1] like this: foo = do r <- remaining rbs <- case r of 0

Re: [Haskell-cafe] Success and one last issue with Data.Binary

2009-06-02 Thread Thomas DuBuisson
> I think getRemainingLazyByteString expects at least one byte No, it works with an empty bytestring. Or, my tests do with binary 0.5.0.1. The specific error means you are requiring more data than providing. First check the length of the bytestring you pass in to the to level decode (or 'get') ro

Re: [Haskell-cafe] Success and one last issue with Data.Binary

2009-06-02 Thread John Van Enk
Thomas, You're correct. For some reason, I based my advice on the thought that 19 was the minimum size instead of 13. On Tue, Jun 2, 2009 at 1:24 PM, Thomas DuBuisson wrote: >> I think getRemainingLazyByteString expects at least one byte > No, it works with an empty bytestring.  Or, my tests do

Re: [Haskell-cafe] Checking a value against a passed-in constructor?

2009-06-02 Thread Ryan Ingram
On Tue, Jun 2, 2009 at 3:50 AM, Dan wrote: > You hit the nail on the head.  "Why I am doing this" is because of > boilerplate. Boilerplate gives me rashes and bulbous spots on the nose. > > Consider the following Ruby code: > >        def check(zeClass, zeValue) >                zeValue.is_a? zeCl

[Haskell-cafe] Compiling a windows app - embedding a manifest

2009-06-02 Thread GüŸnther Schmidt
Hi all, is it possible to make ghc embedd a particular manifest in the .exe during the compilation process? Günther ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe

Re: [Haskell-cafe] Success and one last issue with Data.Binary

2009-06-02 Thread David Leimbach
The thing is I have 19 bytes in the hex string I provided: 13006500040600395032303030 That's 38 characters or 19 bytes. The last 4 are 9P2000 1300 = 4 bytes for 32bit message payload, This is little endian for 19 bytes total. 65 = 1 byte for message type. 65 is "Rversion" or

Re: [Haskell-cafe] Success and one last issue with Data.Binary

2009-06-02 Thread John Van Enk
I think Thomas' point was that some other branch in `getSpecific' is running. Is there a chance we can see the rest of `getSpecific'? On Tue, Jun 2, 2009 at 4:20 PM, David Leimbach wrote: > The thing is I have 19 bytes in the hex string I provided: > 13006500040600395032303030 > That'

Re: [Haskell-cafe] Success and one last issue with Data.Binary

2009-06-02 Thread David Leimbach
On Tue, Jun 2, 2009 at 10:24 AM, Thomas DuBuisson < thomas.dubuis...@gmail.com> wrote: > > I think getRemainingLazyByteString expects at least one byte > No, it works with an empty bytestring. Or, my tests do with binary > 0.5.0.1. > > The specific error means you are requiring more data than pro

Re: [Haskell-cafe] Success and one last issue with Data.Binary

2009-06-02 Thread David Leimbach
On Tue, Jun 2, 2009 at 1:28 PM, John Van Enk wrote: > I think Thomas' point was that some other branch in `getSpecific' is > running. Is there a chance we can see the rest of `getSpecific'? Sure: (In the meantime, I'll try the suggested code from before) get = do s <- getWord32le

Re: [Haskell-cafe] Success and one last issue with Data.Binary

2009-06-02 Thread John Van Enk
Perhaps there's some place in your code that's forcing the lazy read to consume more. Perhaps you could replace it with an explict (and strict) getBytes[1] in combination with remaining[2]? Is there a reason you want to use lazy byte strings rather than forcing full consumption? Do the 9P packets

Re: [Haskell-cafe] Success and one last issue with Data.Binary

2009-06-02 Thread John Van Enk
What happens if you use `getRemainingLazyByteString' in your error branch instead of `getLazyByteString'? On Tue, Jun 2, 2009 at 4:31 PM, David Leimbach wrote: > > > On Tue, Jun 2, 2009 at 1:28 PM, John Van Enk wrote: >> >> I think Thomas' point was that some other branch in `getSpecific' is >>

[Haskell-cafe] code reviewers wanted for hashed-storage (darcs)

2009-06-02 Thread Eric Kow
Dear Haskellers, Will you have a few spare hours this summer? The Darcs team needs your help! Summary --- We need two volunteers to help us review the standalone hashed-storage module, which will be used by Darcs in the future. Background -- Darcs supports 'hashed' repositories in wh

Re: [Haskell-cafe] Compiling a windows app - embedding a manifest

2009-06-02 Thread Bulat Ziganshin
Hello Gu?nther, Wednesday, June 3, 2009, 12:11:15 AM, you wrote: > Hi all, > is it possible to make ghc embedd a particular manifest in the .exe > during the compilation process? add to .rc file: 1 24 "app.manifest" and put manifect into app.manifest -- Best regards, Bulat

Re: [Haskell-cafe] Success and one last issue with Data.Binary

2009-06-02 Thread David Leimbach
On Tue, Jun 2, 2009 at 1:32 PM, John Van Enk wrote: > Perhaps there's some place in your code that's forcing the lazy read > to consume more. Perhaps you could replace it with an explict (and > strict) getBytes[1] in combination with remaining[2]? Unfortunately, I'm using a Lazy ByteString netw

Re: [Haskell-cafe] Success and one last issue with Data.Binary

2009-06-02 Thread David Leimbach
On Tue, Jun 2, 2009 at 1:36 PM, John Van Enk wrote: > What happens if you use `getRemainingLazyByteString' in your error > branch instead of `getLazyByteString'? > I actually am using getRemainingLazyByteString right now, and it still thinks I'm asking for a 20th byte. if I delete the other gua

Re: [Haskell-cafe] Success and one last issue with Data.Binary

2009-06-02 Thread Thomas DuBuisson
Again, I can't reproduce your problem. Are you getting data through some previous Binary instance before calling the routines you show us here? The code I tested with is below - I've tried it with both 'getSpecific' paths by commenting out one path at a time. Both methods work, shown below. Tho

Re: [Haskell-cafe] Success and one last issue with Data.Binary

2009-06-02 Thread John Van Enk
Just so we know that it's not the issue, what version of binary are you using? The most current one is 0.5.0.1. On Tue, Jun 2, 2009 at 4:46 PM, David Leimbach wrote: > > > On Tue, Jun 2, 2009 at 1:36 PM, John Van Enk wrote: >> >> What happens if you use `getRemainingLazyByteString' in your error

Re: [Haskell-cafe] Success and one last issue with Data.Binary

2009-06-02 Thread David Leimbach
0.5.0.1 On Tue, Jun 2, 2009 at 1:56 PM, John Van Enk wrote: > Just so we know that it's not the issue, what version of binary are > you using? The most current one is 0.5.0.1. > > On Tue, Jun 2, 2009 at 4:46 PM, David Leimbach wrote: > > > > > > On Tue, Jun 2, 2009 at 1:36 PM, John Van Enk wrot

Re: [Haskell-cafe] Success and one last issue with Data.Binary

2009-06-02 Thread David Leimbach
On Tue, Jun 2, 2009 at 1:56 PM, Thomas DuBuisson wrote: > Again, I can't reproduce your problem. Are you getting data through > some previous Binary instance before calling the routines you show us > here? Ah good question... I'm calling "decode", but it's not clear that it's even running my i

Re: [Haskell-cafe] Success and one last issue with Data.Binary

2009-06-02 Thread Thomas DuBuisson
It will run the instance of the inferred type (or you can provide a type signature to force it). I've done this often before with lists - trying to read in some arbitrary, typically high, number of elements causes issues :-) Thomas On Tue, Jun 2, 2009 at 2:07 PM, David Leimbach wrote: > > > On

Re: [Haskell-cafe] Success and one last issue with Data.Binary

2009-06-02 Thread David Leimbach
On Tue, Jun 2, 2009 at 2:07 PM, David Leimbach wrote: > > > On Tue, Jun 2, 2009 at 1:56 PM, Thomas DuBuisson < > thomas.dubuis...@gmail.com> wrote: > >> Again, I can't reproduce your problem. Are you getting data through >> some previous Binary instance before calling the routines you show us >>

[Haskell-cafe] ANN: Anglohaskell 2009

2009-06-02 Thread Philippa Cowderoy
Anglohaskell 2009 is go! I'm taking on the mantle of organiser, and Microsoft Research have offered us space for talks in Cambridge again. The event will be held on the 7th and 8th of August. More info at http://www.haskell.org/haskellwiki/AngloHaskell/2009 , planning and discussion in #anglohaskel

[Haskell-cafe] ANNOUNCE: The Haskell Platform 2009.2.0.1

2009-06-02 Thread Don Stewart
We're pleased to announce the second release of the Haskell Platform: a single, standard Haskell distribution for everyone. The specification, along with installers (including Windows and Unix installers for a full Haskell environment) are available. Download the Haskell Platform 2009.2.0.1:

Re: [Haskell-cafe] ANN: Anglohaskell 2009

2009-06-02 Thread Henk-Jan van Tuyl
On Tue, 02 Jun 2009 23:45:18 +0200, Philippa Cowderoy wrote: Anglohaskell 2009 is go! F.A.B. :) -- Regards, Henk-Jan van Tuyl -- http://functor.bamikanarie.com http://Van.Tuyl.eu/ -- ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org ht

[Haskell-cafe] beginners question about fromMaybe

2009-06-02 Thread Nico Rolle
hi there heres a code snipped, don't care about the parameters. the thing is i make a lookup on my map "m" and then branch on that return value probePhase is sc [] m = [] probePhase is sc (x:xs) m | val == Nothing = probePhase is sc xs m | otherwise = jr ++ probePhase is sc xs m

Re: [Haskell-cafe] beginners question about fromMaybe

2009-06-02 Thread Raynor Vliegendhart
If you're absolutely certain that the lookup always succeeds, then you can use pattern matching as follows: where jr = joinTuples sc x val key = getPartialTuple is x Just val = Map.lookup key m On 6/3/09, Nico Rolle wrote: > hi there > > heres a code s

Re: [Haskell-cafe] beginners question about fromMaybe

2009-06-02 Thread Luke Palmer
On Tue, Jun 2, 2009 at 4:59 PM, Nico Rolle wrote: > hi there > > heres a code snipped, don't care about the parameters. > the thing is i make a lookup on my map "m" and then branch on that return > value > > probePhase is sc [] m = [] > probePhase is sc (x:xs) m >| val == Nothing = probePhas

Re: [Haskell-cafe] beginners question about fromMaybe

2009-06-02 Thread Raynor Vliegendhart
I just noticed that my suggestion doesn't work. You're testing whether val is Nothing and in my code snipped val has a different type. On 6/3/09, Raynor Vliegendhart wrote: > If you're absolutely certain that the lookup always succeeds, then you > can use pattern matching as follows: > > >

Re: [Haskell-cafe] beginners question about fromMaybe

2009-06-02 Thread Toby Hutton
On Wed, Jun 3, 2009 at 8:59 AM, Nico Rolle wrote: > hi there > > heres a code snipped, don't care about the parameters. > the thing is i make a lookup on my map "m" and then branch on that return > value > > probePhase is sc [] m = [] > probePhase is sc (x:xs) m >    | val == Nothing  = probePhas

[Haskell-cafe] Cabal/primes

2009-06-02 Thread michael rice
Finally got adventurous enough to get Cabal working, downloaded the primes package, and got the following error message when trying isPrime. Am I missing something here? Michael == [mich...@localhost ~]$ ghci GHCi, version 6.10.1: http://www.haskell.org/ghc/  :? for help Loadin

Re: [Haskell-cafe] beginners question about fromMaybe

2009-06-02 Thread Toby Hutton
>  where next = probePhase ... >            key = ... > Argh, I really wish Gmail would allow me to compose in a fixed with width font! Does anyone know of a setting or something that I'm missing? ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org h

Re: [Haskell-cafe] Cabal/primes

2009-06-02 Thread Bertram Felgenhauer
michael rice wrote: > Finally got adventurous enough to get Cabal working, downloaded the > primes package, and got the following error message when trying > isPrime. Am I missing something here? The Data.Numbers.Primes module of the primes package does not implement 'isPrime'. The Numbers packag

Re: [Haskell-cafe] Checking a value against a passed-in constructor?

2009-06-02 Thread wren ng thornton
Ryan Ingram wrote: Dan wrote: > I figured there would be a clever Haskell idiom that would give me a > similarly concise route. Does it really require Template Haskell? I can > barely parse regular Haskell as it is.. [...] Alternatively, you can define a fold[1] once: myval :: MyVal -> (Bool

Re: [Haskell-cafe] beginners question about fromMaybe

2009-06-02 Thread Ryan Ingram
Luke's answer is great (although it changes argument order). Hint: http://www.haskell.org/haskellwiki/Things_to_avoid#Avoid_explicit_recursion I also like the "pattern guards" GHC extension; I tend to use it over "maybe" and "either". I find the resulting code more readable: > {-# LANGUAGE Patte

[Haskell-cafe] type checking that I can't figure out ....

2009-06-02 Thread Vasili I. Galchin
Hello Haskellers, I isolated to a not so small piece: > {-# OPTIONS -fglasgow-exts #-} > {-# LANGUAGE UndecidableInstances #-} > import Control.Monad.Identity > import Control.Monad.Reader > import Control.Monad.State > import qualified Data.List as L > import qualified Data.Map as M > impo

Re: [Haskell-cafe] type checking that I can't figure out ....

2009-06-02 Thread Michael Snoyman
> remLookupFwd :: (ReVars m t) => SimplRe t -> ReM m t (ReInfo t) > remLookupFwd re > = do fwd <- gets resFwdMap > -- let { Just reinfo = M.lookup fwd re }-- PROBLEM >reinfo <- liftMaybe $ M.lookup re fwd -- PROBLEM >return reinfo > >

Re: [Haskell-cafe] type checking that I can't figure out ....

2009-06-02 Thread Vasili I. Galchin
Hi Michael, Let me look tomorrow morning. In any case, many thanks! Kind regards, Vasili On Tue, Jun 2, 2009 at 11:12 PM, Michael Snoyman wrote: > > remLookupFwd :: (ReVars m t) => SimplRe t -> ReM m t (ReInfo t) > > remLookupFwd re > > = do fwd <- gets resFwdMap > > -- let { Jus

Re: [Haskell-cafe] type checking that I can't figure out ....

2009-06-02 Thread ajb
G'day Vasili. This should do it: remLookupFwd :: (ReVars m t) => SimplRe t -> ReM m t (ReInfo t) remLookupFwd re = do fwd <- gets resFwdMap let { Just reinfo = fromJust (M.lookup re fwd) } return reinfo The FiniteMap lookup operation took its arguments in the opposite order. Tha

Re: [Haskell-cafe] ANN: Anglohaskell 2009

2009-06-02 Thread Magnus Therning
Henk-Jan van Tuyl wrote: On Tue, 02 Jun 2009 23:45:18 +0200, Philippa Cowderoy wrote: Anglohaskell 2009 is go! F.A.B. :) Yes, excellent news, and this time I'll make sure to attend, especially since it's back in Cambridge again. /M -- Magnus Therning(OpenPGP:

Re: [Haskell-cafe] type checking that I can't figure out ....

2009-06-02 Thread Daniel Fischer
Am Mittwoch 03 Juni 2009 06:12:46 schrieb Michael Snoyman: > I made two changes: > > 1. You had the arguments to M.lookup backwards. > 2. lookup does not return any generalized Monad, just Maybe (I think that > should be changed). Data.Map.lookup used to return a value in any monad you wanted, I