Re[2]: [Haskell-cafe] Deadlock in real number multiplication (Was: Where's the problem ?)

R> Another interesting thing I've discovered is: Prelude>> length [1..100] R> 100 Prelude>> Data.List.genericLength [1..100] R> *** Exception: stack overflow R> Maybe there is something wrong with Integer ? No, there is something wrong with genericLength: Prelude> Data.List.foldl (

Re: [Haskell-cafe] Deadlock in real number multiplication (Was: Where's the problem ?)

Henning Thielemann wrote: > > > On Wed, 4 Jul 2007, Rome wrote: > >> > A friend of mine compiled it under Linux and got: >> > . >> > . >> > . >> > 32779 : 1 1 ---32776--> 0 >> > 32780 : 1 0 ---32777--> -1 >> > Main: Ix{Integer}.index: Index (32766) out of range ((0,32765)) >> > >> > If

Re: [Haskell-cafe] folds with escapes

> Can you do dropWhile in terms of foldr? One can write foldr that represents drop or dropWhile of the original foldr. One can do even more: zip two folds. That is, obtain a fold that is equivalent to zipping up two lists represented by the original folds. Even furthermore, one can do all these t

[Haskell-cafe] Lightweight sequent calculus and linear abstractions

Conor McBride has posed an interesting problem: >implement constructors > P v for embedding pure values v > Ofor holes > f :$ a for application, left-associative >and an interpreting function > emmental >such that > emmental (P (+) :$ (P (*) :$ O

Re: [Haskell-cafe] System.Exit

On Thu, Jul 05, 2007 at 02:04:32PM +1000, Thomas Conway wrote: > Hi All, > > Can anyone tell me what System.Exit.exitWith is actually supposed to > do? As far as I can tell, it seems to be a synonym of (return ()). > > Okay, I'll stop being provocative and try and be helpful. > > So I have a web se

Re: [Haskell-cafe] System.Exit

On Jul 5, 2007, at 0:04 , Thomas Conway wrote: quitHandler sok addr = do tidyUpEverything sendOkResponse sok sClose sok System.Exit.exitWith ExitSuccess All nice and simple. All except one detail: it doesn't actually work. It prints exit: ExitSuccess but the "doit" loo

[Haskell-cafe] System.Exit

Hi All, Can anyone tell me what System.Exit.exitWith is actually supposed to do? As far as I can tell, it seems to be a synonym of (return ()). Okay, I'll stop being provocative and try and be helpful. So I have a web server, which like the one in The Literature(TM), essentially has a main loop

Re: [Haskell-cafe] Re: Abstraction leak

On 7/5/07, Donald Bruce Stewart <[EMAIL PROTECTED]> wrote: Yep. The current impl is: mmapFile :: FilePath -> IO ByteString mmapFile f = mmap f >>= \(fp,l) -> return $! PS fp 0 l mmap :: FilePath -> IO (ForeignPtr Word8, Int) mmap = do ... p <- mmap l fd

Re: [Haskell-cafe] folds with escapes

On 05/07/2007, at 10:08 AM, Michael Vanier wrote: Can you do dropWhile in terms of foldr? I don't see how. Mike I considered that very question in an article I wrote for the Monad.Reader magazine: http://www.haskell.org/sitewiki/images/1/14/TMR-Issue6.pdf If you are really keen, yo

Re: [Haskell-cafe] Re: Abstraction leak

drtomc: > On 7/4/07, Donald Bruce Stewart <[EMAIL PROTECTED]> wrote: > >Can we do a cheap bytestring binding to libxml, to avoid any initial > >String processing? > > For my part, it's not too big an issue. A version of HaXml or at least > Parsec built on top of ByteString would be a good start. I

Re: [Haskell-cafe] folds with escapes

dm.maillists: > On Thursday 05 July 2007 11:20, Michael Vanier wrote: > > Again, I'm sure this has been done before (and no doubt better); I'd > > appreciate any pointers to previous work along these lines. > > Takusen is, if I recall correctly, based around a generalised fold supporting > accumu

Re: [Haskell-cafe] folds with escapes

2007/7/4, Michael Vanier <[EMAIL PROTECTED]>: That's cool -- good point. takeWhile is also trivially defined in terms of foldr: > takeWhile p = foldr (\x r -> if p x then x:r else []) [] Can you do dropWhile in terms of foldr? I don't see how. I 'm very bad in english, sorry. Here is a

Re: [Haskell-cafe] Parsers are monadic?

(b) i like my combinator grammars to be reversible, so that a single grammar specification can be used for both parsing and unparsing/pretty-printing. that means i have to define the details myself anyway. Oh cool - this is something I have wanted for a long time. Anything released

Re: [Haskell-cafe] folds with escapes

On Thursday 05 July 2007 11:20, Michael Vanier wrote: > Again, I'm sure this has been done before (and no doubt better); I'd > appreciate any pointers to previous work along these lines. Takusen is, if I recall correctly, based around a generalised fold supporting accumulation and early terminati

Re: [Haskell-cafe] folds with escapes

On Wed, Jul 04, 2007 at 05:08:01PM -0700, Michael Vanier wrote: > That's cool -- good point. takeWhile is also trivially defined in terms of > foldr: > > > takeWhile p = foldr (\x r -> if p x then x:r else []) [] > > Can you do dropWhile in terms of foldr? I don't see how. dropWhile cannot be e

Re: [Haskell-cafe] folds with escapes

That's cool -- good point. takeWhile is also trivially defined in terms of foldr: > takeWhile p = foldr (\x r -> if p x then x:r else []) [] Can you do dropWhile in terms of foldr? I don't see how. Mike Stefan O'Rear wrote: On Wed, Jul 04, 2007 at 04:20:20PM -0700, Michael Vanier wrote: I'

Re: [Haskell-cafe] folds with escapes

On Wed, Jul 04, 2007 at 04:20:20PM -0700, Michael Vanier wrote: > I'm sure this has been done a hundred times before, but a simple > generalization of foldl just occurred to me and I wonder if there's > anything like it in the standard libraries (I couldn't find anything). > Basically, I was tryi

[Haskell-cafe] folds with escapes

I'm sure this has been done a hundred times before, but a simple generalization of foldl just occurred to me and I wonder if there's anything like it in the standard libraries (I couldn't find anything). Basically, I was trying to define the "any" function in terms of a fold, and my first try w

Re: [Haskell-cafe] Binary serialization, was Re: Abstraction leak

phil: > On Wed, Jul 04, 2007 at 09:44:13PM +1000, Donald Bruce Stewart wrote: > >Binary instances are pretty easy to write. For a simple data type: > > > > > instance Binary Exp where > > > put (IntE i) = do put (0 :: Word8) > > > put i

Re: [Haskell-cafe] Binary serialization, was Re: Abstraction leak

On Wed, Jul 04, 2007 at 07:36:11PM +0100, Andrew Coppin wrote: Philip Armstrong wrote: [1] Which sick application *needs* intermixed endianness? *Clearly* you've never been to Singapore... ...er, I mean, "Ever tried playing with networking protocol stacks?" No (thankfully?). Phil -- http:

Re: [Haskell-cafe] The Garbage Collector Ate My Homework

On 7/3/07, Thomas Conway <[EMAIL PROTECTED]> wrote: Okay, so a bit of a tweak of the RTS flags, I got a DRAMATIC improvement: 239,434,077,460 bytes allocated in the heap 9,034,063,712 bytes copied during GC (scavenged) 132,748,740 bytes copied during GC (not scavenged) 226,313,736 bytes maximum

Re: [Haskell-cafe] A very nontrivial parser

On Wednesday 04 July 2007, Andrew Coppin wrote: > Well, I eventually got it to work correctly... (!) > > My goal is to be able to stack multiple parsers one on top of the other > - but be able to *change* the stack half way through parsing if needed. > This I eventually succeeded in doing. The exte

[Haskell-cafe] A very nontrivial parser

Well, I eventually got it to work correctly... (!) My goal is to be able to stack multiple parsers one on top of the other - but be able to *change* the stack half way through parsing if needed. This I eventually succeeded in doing. The external interface is fairly simple, but the type signatu

[Haskell-cafe] Parsec - collecting patches - How to contact maintainer Daan Leijen ?

Paresc is a great piece of software. But there are some things which do bother me occasionally. A short list: Things I'd like to change: a) custom location tracking. (I've already written a patch, but I haven't tested how much speed will suffer? Which would be a nice test?) b) Add a function

Re[2]: [Haskell-cafe] Binary serialization, was Re: Abstraction leak

Hello Philip, Wednesday, July 4, 2007, 9:41:27 PM, you wrote: > I'm thinking of the elimination of the boxing of values drawn out of > the input stream where possible, eg if I was writing a stream > processor that folded across the values in the input stream, it would > (presumably) be more effic

Re: [Haskell-cafe] Very simple parser

On Thu, Jul 05, 2007 at 12:58:06AM +1000, Alexis Hazell wrote: > On Tuesday 03 July 2007 09:51, Arie Peterson wrote: > > > No, there is a 'State s' monad provided (for arbitrary state type 's'), > > which implements the 'get' and 'put' methods. In other words, 'State s' is > > an instance of the '

Re: [Haskell-cafe] Deadlock in real number multiplication (Was: Where's the problem ?)

On Wed, 4 Jul 2007, Rome wrote: > > A friend of mine compiled it under Linux and got: > > . > > . > > . > > 32779 : 1 1 ---32776--> 0 > > 32780 : 1 0 ---32777--> -1 > > Main: Ix{Integer}.index: Index (32766) out of range ((0,32765)) > > > > If I convert every Integer into Int and use inste

Re: [Haskell-cafe] Deadlock in real number multiplication (Was: Where's the problem ?)

> A friend of mine compiled it under Linux and got: > . > . > . > 32779 : 1 1 ---32776--> 0 > 32780 : 1 0 ---32777--> -1 > Main: Ix{Integer}.index: Index (32766) out of range ((0,32765)) > > If I convert every Integer into Int and use instead of the generic list > functions the prelude-list

Re: [Haskell-cafe] Binary serialization, was Re: Abstraction leak

Philip Armstrong wrote: [1] Which sick application *needs* intermixed endianness? *Clearly* you've never been to Singapore... ...er, I mean, "Ever tried playing with networking protocol stacks?" ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.o

Re: [Haskell-cafe] Haskell's "partial application" (not currying!) versus Business Objects Gem Cutter's "burning"

Hi Marc Thanks for giving it a go! On 4 Jul 2007, at 17:33, Marc A. Ziegert wrote: exercise done. :D there is still a problem with the functional dependencies. see last line of code. - marc Looks like a good start. Quite different from the way I did it. I can assure you that it's possib

Re: [Haskell-cafe] Sparse documentation

Jules Bean wrote: Andrew Coppin wrote: Essentially I want to run a parser on top of a parser, and I think maybe this is the way to do it. I doubt monad transformers are the answer. I imagine you just want to one run parser over the result of the previous, which is just function composition,

Re: [Haskell-cafe] Sparse documentation

Simon Peyton-Jones wrote: Writing documentation for libraries is one way in which ordinary Haskell users can really contribute to the Haskell community. It’s not hard to do (grab the Darcs repo, type away), and it’s widely appreciated. People often don’t feel “qualified” do to this, but docu

[Haskell-cafe] Re: Deadlock in real number multiplication (Was: Where's the problem ?)

On Wed, 4 Jul 2007, Rome wrote: > I write a program for fast online multiplication, this means, leading digits > are computed first, so this program is able to handle real numbers. > > My program and Source-Code is available under > http://www.romeinf04.de http://www.romeinf04.de > > but only wit

Re: [Haskell-cafe] Binary serialization, was Re: Abstraction leak

On Wed, Jul 04, 2007 at 09:15:59PM +0400, Bulat Ziganshin wrote: Does that mean that the code is unwritten or that the documentation is unwritten. IAMFI :) of course all "unwritten" notes means unfinished docs. library contains more than 100 functions so it was not easy to document them all. yo

Re: [Haskell-cafe] Very simple parser

Alexis Hazell wrote: | This may be a stupid question, but i don't understand how (indeed, if) one | can | maintain multiple states using the State monad, since 'get' etc. don't | seem | to require that one specify which particular copy of a State monad one | wishes | to 'get' from, 'put' to etc.?

Re: [Haskell-cafe] Where's the problem ?

On Wed, Jul 04, 2007 at 07:30:55AM -0700, Rome wrote: > I write a program for fast online multiplication, this means, leading digits > are computed first, so this program is able to handle real numbers. > > My program and Source-Code is available under > http://www.romeinf04.de http://www.romeinf

Re: [Haskell-cafe] Binary serialization, was Re: Abstraction leak

On Wed, Jul 04, 2007 at 02:50:42PM +0100, Philip Armstrong wrote: >> The Data.Binary comes with one tool to derive these. The DrIFT >> preprocessor >> also can, as can Stefan O'Rear's SYB deriver. >> >> I just write them by hand, or use the tool that comes with the lib. >> >> More docs here, >>

Re[2]: [Haskell-cafe] Binary serialization, was Re: Abstraction leak

Hello Philip, Wednesday, July 4, 2007, 7:31:56 PM, you wrote: > On Wed, Jul 04, 2007 at 06:52:08PM +0400, Bulat Ziganshin wrote: >>Hello Philip, >> >>Wednesday, July 4, 2007, 5:50:42 PM, you wrote: >>> This doesn't seem to deal with endianness. Am I missing something? >> >>alternative: >>http://h

Re: [Haskell-cafe] Parsers are monadic?

"Claus Reinke" <[EMAIL PROTECTED]> wrote: > (b) i like my combinator grammars to be reversible, so that a single > grammar specification can be used for both parsing and > unparsing/pretty-printing. that means i have to define the > details myself anyway. Oh cool - this is something

Re: [Haskell-cafe] Abstraction leak

Andrew Coppin <[EMAIL PROTECTED]> wrote: > While we're on the subject... am I the first person to notice that > Haskell doesn't appear to have much support for fiddling with streams > of bits? See "The Bits Between The Lambdas: Binary Data in a Lazy Functional Language" Malcolm Wallace and

Re: [Haskell-cafe] Haskell's "partial application" (not currying!) versus Business Objects Gem Cutter's "burning"

exercise done. :D there is still a problem with the functional dependencies. see last line of code. - marc Am Mittwoch, 4. Juli 2007 14:22 schrieb Conor McBride: >{? * 10 + ?} 4 2 = 42 > > > > (3) Exercise fo

Re: [Haskell-cafe] Binary serialization, was Re: Abstraction leak

On Wed, Jul 04, 2007 at 06:52:08PM +0400, Bulat Ziganshin wrote: Hello Philip, Wednesday, July 4, 2007, 5:50:42 PM, you wrote: This doesn't seem to deal with endianness. Am I missing something? alternative: http://haskell.org/haskellwiki/Library/AltBinary http://haskell.org/haskellwiki/Librar

Re: [Haskell-cafe] Very simple parser

On Tuesday 03 July 2007 09:51, Arie Peterson wrote: > No, there is a 'State s' monad provided (for arbitrary state type 's'), > which implements the 'get' and 'put' methods. In other words, 'State s' is > an instance of the 'MonadState s' class. This terminology can be really > confusing at first.

Re[2]: [Haskell-cafe] Binary serialization, was Re: Abstraction leak

Hello Philip, Wednesday, July 4, 2007, 5:50:42 PM, you wrote: > This doesn't seem to deal with endianness. Am I missing something? alternative: http://haskell.org/haskellwiki/Library/AltBinary http://haskell.org/haskellwiki/Library/Streams -- Best regards, Bulatmail

[Haskell-cafe] Where's the problem ?

Hi everyone, I write a program for fast online multiplication, this means, leading digits are computed first, so this program is able to handle real numbers. My program and Source-Code is available under http://www.romeinf04.de http://www.romeinf04.de but only with german comments, because th

Re: [Haskell-cafe] Binary serialization, was Re: Abstraction leak

On Wed, Jul 04, 2007 at 09:44:13PM +1000, Donald Bruce Stewart wrote: Binary instances are pretty easy to write. For a simple data type: > instance Binary Exp where > put (IntE i) = do put (0 :: Word8) > put i > put (O

[Haskell-cafe] Re: Sparse documentation

Claus Reinke wrote: >> Simon, if the less-talented among us (like me) want to contribute to >> GHC's docs -- and especially documenting the libraries -- what's the >> best way to go about this? I'm not too comfortable with the notion of >> just going into GHC's guts and Haddocking the comments, co

Re: [Haskell-cafe] Haskell's "partial application" (not currying!) versus Business Objects Gem Cutter's "burning"

Hi Jules Your explanation of lambda-abstraction, dealing in full generality with both scope and multiplicity, is a good one. But it's still interesting to investigate the possibility of a privileged notation for linear abstraction, based on leaving holes in things, by way of illustrating th

Re: [Haskell-cafe] Re: Abstraction leak

phil: > On Wed, Jul 04, 2007 at 09:02:15PM +1000, Donald Bruce Stewart wrote: > >phil: > >>On Sun, Jul 01, 2007 at 06:07:13PM +0100, Andrew Coppin wrote: > >>>I haven't actually tried, but presumably a TCP connection is represented > >>>in the same way as a file, and so has the same problems. > >>

Re: [Haskell-cafe] Re: Abstraction leak

On Wed, Jul 04, 2007 at 09:02:15PM +1000, Donald Bruce Stewart wrote: phil: On Sun, Jul 01, 2007 at 06:07:13PM +0100, Andrew Coppin wrote: >I haven't actually tried, but presumably a TCP connection is represented >in the same way as a file, and so has the same problems. > >Basically doing bina

Re: [Haskell-cafe] Re: Abstraction leak

drtomc: > >Anyone trying to do any of this? > > I've done some work in this area. I'm particularly interested in > manipulating ASN.1 in haskell. Actually, my first use of Parsec was an > ASN.1 parser. I'd done one previously in Spirit (the Boost C++ rip-off > of parsec), but semantic actions were

Re: [Haskell-cafe] Re: Abstraction leak

Anyone trying to do any of this? I've done some work in this area. I'm particularly interested in manipulating ASN.1 in haskell. Actually, my first use of Parsec was an ASN.1 parser. I'd done one previously in Spirit (the Boost C++ rip-off of parsec), but semantic actions were horrible in the ex

Re: [Haskell-cafe] Re: Abstraction leak

phil: > On Sun, Jul 01, 2007 at 06:07:13PM +0100, Andrew Coppin wrote: > >I haven't actually tried, but presumably a TCP connection is represented > >in the same way as a file, and so has the same problems. > > > >Basically doing binary I/O seems to be one of those things that in Haskell > >falls

Re: [Haskell-cafe] Sparse documentation

Simon, if the less-talented among us (like me) want to contribute to GHC's docs -- and especially documenting the libraries -- what's the best way to go about this? I'm not too comfortable with the notion of just going into GHC's guts and Haddocking the comments, contributing patches willy-nilly

Re: [Haskell-cafe] Re: Abstraction leak

On Sun, Jul 01, 2007 at 06:07:13PM +0100, Andrew Coppin wrote: I haven't actually tried, but presumably a TCP connection is represented in the same way as a file, and so has the same problems. Basically doing binary I/O seems to be one of those things that in Haskell falls into the class of "i

[Haskell-cafe] Playing with delimited continuations

Hello, My interest was recently caught reading some of Oleg Kiselyov's material on delimited continuations, and so I decided to look into them a little closer. Don Stewart also mentioned in passing on #haskell that'd it'd be nice to have support for delimited continuations either in the standar

Re: [Haskell-cafe] Sparse documentation

Andrew Coppin wrote: Essentially I want to run a parser on top of a parser, and I think maybe this is the way to do it. I doubt monad transformers are the answer. I imagine you just want to one run parser over the result of the previous, which is just function composition, modulo a sensible w

RE: [Haskell-cafe] Sparse documentation

On Wed, 2007-04-07 at 08:03 +0100, Simon Peyton-Jones wrote: > | Fortunately, some kind soul has gone through and converted the > | documentation to haddock format: > | http://hackage.haskell.org/trac/ghc/ticket/1410 > | > | So it'll all appear in the html docs in the next version. In the mean > |

RE: [Haskell-cafe] Sparse documentation

Writing documentation for libraries is one way in which ordinary Haskell users can really contribute to the Haskell community. It's not hard to do (grab the Darcs repo, type away), and it's widely appreciated. People often don't feel "qualified" do to this, but documentation written by an inte

RE: [Haskell-cafe] Sparse documentation

| Fortunately, some kind soul has gone through and converted the | documentation to haddock format: | http://hackage.haskell.org/trac/ghc/ticket/1410 | | So it'll all appear in the html docs in the next version. In the mean | time one can look at the haddock comments in the source: | http://darcs.h