Re: [Haskell-cafe] Re: Library design question

On Fri, Sep 19, 2008 at 7:02 PM, Andre Nathan <[EMAIL PROTECTED]> wrote: > On Fri, 2008-09-19 at 23:16 +0200, Daniel Fischer wrote: >> Yes. What's IO gotta do with it? > > I did it because of randomIO :( > >> (or what about StateT (Graph a b) (State StdGen) ?). > > Now there's something I wouldn't

Re: [Haskell-cafe] Ropes

RafaelGCPP.Linux: >Hi all, > >Is there any implementation of the rope data structure in Haskell? > >I couldn't find any on Hackage, and I am intending to implement it. There's no mature rope implementation. Can you write a bytestring-rope that outperforms lazy bytestrings please :) _

Re: [Haskell-cafe] Ropes

I think Data.Sequence uses fingertrees which are pretty fast. I used a handgrown rope-like structure for ICFPC07 but I wish I had known about Sequence; it would have likely just been better. -- ryan 2008/9/19 Rafael Gustavo da Cunha Pereira Pinto <[EMAIL PROTECTED]>: > Hi all, > > Is there any

Re: [Haskell-cafe] Re: XML (HXML) parsing :: GHC 6.8.3 space leak from 2000

Lev Walkin wrote: Simon Marlow wrote: Lev Walkin wrote: I wondered why would a contemporary GHC 6.8.3 exhibit such a leak? After all, the technique was known in 2000 (and afir by Wadler in '87) and one would assume Joe English's reference to "most other Haskell systems" ought to mean GHC. Th

Re: [Haskell-cafe] ANNOUNCE: citeproc-hs, a Haskell implementation of the Citation Style Language designed for Pandoc

On Sat, Sep 13, 2008 at 1:33 PM, Andrea Rossato <[EMAIL PROTECTED]> wrote: > Hello, > > I'm happy to announce the first release of citeproc-hs, a Haskell > implementation of the Citation Style Language. > > citeproc-hs adds to Pandoc, the famous Haskell text processing tool, a > Bibtex like citatio

[Haskell-cafe] Ropes

Hi all, Is there any implementation of the rope data structure in Haskell? I couldn't find any on Hackage, and I am intending to implement it. Regards, Rafael Gustavo da Cunha Pereira Pinto Electronic Engineer, MSc. ___ Haskell-Cafe mailing list Haske

Re: [Haskell-cafe] Parsing arguments and reading configuration

On Fri, Sep 19, 2008 at 7:35 PM, Antoine Latter <[EMAIL PROTECTED]> wrote: > I'm not sure how well it would hold up under maintenance, but you coud > have a config sum-type which is itself a monoid, and then create two > of them: > And by sum-type I mean product type. Sheesh. Although having you

Re: [Haskell-cafe] Parsing arguments and reading configuration

2008/9/19 Magnus Therning <[EMAIL PROTECTED]>: > > First I thought I'd treat the configuration in a similar way, but then I > noticed a slight ordering problem. The command line arguments should > take priority over the contents of the configuration file, but the > location of the configuration ca

Re: [Haskell-cafe] Parsing arguments and reading configuration

On Fri, 2008-09-19 at 23:24 +0100, Magnus Therning wrote: > Hi all, > > I'm looking for some inspiration for an elegant solution to a silly > little problem I have. This might have a general well-known solution, > or maybe there's something particularly elegant possible in Haskell. I > just thou

Re: [Haskell-cafe] Re: Library design question

On Fri, 2008-09-19 at 23:16 +0200, Daniel Fischer wrote: > Yes. What's IO gotta do with it? I did it because of randomIO :( > (or what about StateT (Graph a b) (State StdGen) ?). Now there's something I wouldn't have thought of... I changed the RandomGraph type to type RandomGraph a b = State

Re: [Haskell-cafe] ANNOUNCE: Extensible and Modular Generics for the Masses (EMGM) 0.1

leather: >Extensible and Modular Generics for the Masses >== > >Extensible and Modular Generics for the Masses (EMGM) is a library for >generic programming in Haskell using type classes. > >This is the initial release of a maintained

[Haskell-cafe] Parsing arguments and reading configuration

Hi all, I'm looking for some inspiration for an elegant solution to a silly little problem I have. This might have a general well-known solution, or maybe there's something particularly elegant possible in Haskell. I just thought I'd ask. When writing a command line tool I want to use a configu

Re: [Haskell-cafe] performance of map reduce

Bryan O'Sullivan ha scritto: On Fri, Sep 19, 2008 at 2:31 PM, Manlio Perillo <[EMAIL PROTECTED] > wrote: By the way, this phrase: "We allow multiple threads to read different chunks at once by supplying each one with a distinct file handle, all reading the

Re: [Haskell-cafe] Re: Python's big challenges, Haskell's big advantages?

On 2008 Sep 19, at 17:14, Manlio Perillo wrote: Brandon S. Allbery KF8NH ha scritto: There are two ways to handle a growable stack; both start with allocating each stack in a separate part of the address space with room to grow it downward. The simpler way uses stack probes on function ent

Re: [Haskell-cafe] performance of map reduce

On Fri, Sep 19, 2008 at 2:31 PM, Manlio Perillo <[EMAIL PROTECTED]>wrote: > > By the way, this phrase: > "We allow multiple threads to read different chunks at once by supplying > each one with a distinct file handle, all reading the same file" > here: > > http://book.realworldhaskell.org/read/con

Re: [Haskell-cafe] performance of map reduce

Don Stewart ha scritto: manlio_perillo: [...] It is possible to implement a map reduce version that can handle gzipped log files? Using the zlib binding on hackage.haskell.org, you can stream multiple zlib decompression threads with lazy bytestrings, and combine the results. This is a bit h

Re: [Haskell-cafe] Re: Library design question

Am Freitag, 19. September 2008 22:55 schrieb Andre Nathan: > On Fri, 2008-09-19 at 10:35 +0200, Christian Maeder wrote: > > I agree. Duncan's version also looks more atomic to me, > > [...] > > OK, so what I have now is > > addVertex :: Int -> a -> Graph a b -> Graph a b > addVertex v l g = Gra

Re: [Haskell-cafe] Re: Python's big challenges, Haskell's big advantages?

Brandon S. Allbery KF8NH ha scritto: On Sep 18, 2008, at 15:10 , Manlio Perillo wrote: Allocation areas are per-CPU, not per-thread. A Concurrent Haskell thread consists of a TSO (thread state object, currently 11 machine words), and a stack, which we currently start with 1KB and grow on dema

Re: [Haskell-cafe] control-timeout with gtk

On Fri, 2008-09-19 at 09:09 -0300, Marco Túlio Gontijo e Silva wrote: > I added the NOINLINE annotations and even tried building with -fno-cse, > but the result was the same. Do you have any other suggestions? A while ago I made a shim using control-event to provide the control-timeout api in Con

Re: [Haskell-cafe] Re: Library design question

On Fri, 2008-09-19 at 09:51 +0200, apfelmus wrote: > There's also Martin Erwig's functional graph library in Data.Graph.Inductive > ( > fgl on hackage). I tried it some time ago, but for large graphs it has a very high memory usage. Best, Andre ___

[Haskell-cafe] Re: Library design question

On Fri, 2008-09-19 at 10:35 +0200, Christian Maeder wrote: > I agree. Duncan's version also looks more atomic to me, [...] OK, so what I have now is addVertex :: Int -> a -> Graph a b -> Graph a b addVertex v l g = Graph adj (numVertices g + 1) (numEdges g) where adj = Map.insert v (l, Ma

Re: [Haskell-cafe] Hackage and HaXml situation

Duncan Coutts wrote: > On Thu, 2008-09-18 at 15:32 -0500, John Goerzen wrote: > Basically for each package we have an optional suggested version > constraint. This would be used in the hackage website to direct people That would solve the problem nicely, I think. Do you have an ETA for this featu

Re: [Haskell-cafe] Lazy vs correct IO [Was: A round of golf]

On Fri, Sep 19, 2008 at 2:51 AM, <[EMAIL PROTECTED]> wrote: > > Lennart Augustsson wrote > >> main = do >>name:_ <- getArgs >>file <- readFile name >>print $ length $ lines file > > Given the stance against top-level mutable variables, I have not > expected to see this Lazy IO code. Af

Re[2]: [Haskell-cafe] performance of map reduce

Hello Don, Friday, September 19, 2008, 9:12:43 PM, you wrote: >> It is possible to implement a map reduce version that can handle gzipped >> log files? > Using the zlib binding on hackage.haskell.org, you can stream multiple > zlib decompression threads with lazy bytestrings, and combine the > r

Re: [Haskell-cafe] lazy strings and parallel read

On Fri, 2008-09-19 at 19:50 +0200, Manlio Perillo wrote: > But if every function that reads the data uses pread, then this should > no more be a problem. > > Or I'm missing some other thing? If you used something like pread instead of hGetContents then yes that would not involve semi-closing a

Re: [Haskell-cafe] Lazy vs correct IO [Was: A round of golf]

On Fri, 2008-09-19 at 16:30 +0100, Lennart Augustsson wrote: > I agree that lazy IO is a can with some worms in it. But it's not that > strange. > The readFile operation is in the IO monad, so it has an effect on the world. > This effect is not finished when readFile returns, and from the world >

Re: [Haskell-cafe] lazy strings and parallel read

Duncan Coutts ha scritto: On Fri, 2008-09-19 at 18:46 +0200, Manlio Perillo wrote: Don Stewart ha scritto: manlio_perillo: Hi. After having read http://book.realworldhaskell.org/read/concurrent-and-multicore-programming.html#id676390 I have a doubt about Data.ByteString.Lazy. Why getContent

Re: [Haskell-cafe] performance of map reduce

manlio_perillo: > Hi again. > > In > http://book.realworldhaskell.org/read/concurrent-and-multicore-programming.html#id676390 > there is a map reduce based log parser. > > I have written an alternative version: > http://paste.pocoo.org/show/85699/ > > but, with a file of 315 MB, I have [1]: >

Re: [Haskell-cafe] lazy strings and parallel read

On Fri, 2008-09-19 at 18:46 +0200, Manlio Perillo wrote: > Don Stewart ha scritto: > > manlio_perillo: > >> Hi. > >> > >> After having read > >> http://book.realworldhaskell.org/read/concurrent-and-multicore-programming.html#id676390 > >> > >> I have a doubt about Data.ByteString.Lazy. > >> > >> Wh

Re: [Haskell-cafe] lazy strings and parallel read

Manlio Perillo ha scritto: Hi. After having read http://book.realworldhaskell.org/read/concurrent-and-multicore-programming.html#id676390 I have a doubt about Data.ByteString.Lazy. Why getContents function don't use pread (or an emulation, if not available)? A correction. getContents s

Re: [Haskell-cafe] lazy strings and parallel read

Don Stewart ha scritto: manlio_perillo: Hi. After having read http://book.realworldhaskell.org/read/concurrent-and-multicore-programming.html#id676390 I have a doubt about Data.ByteString.Lazy. Why getContents function don't use pread (or an emulation, if not available)? Why would it? S

[Haskell-cafe] performance of map reduce

Hi again. In http://book.realworldhaskell.org/read/concurrent-and-multicore-programming.html#id676390 there is a map reduce based log parser. I have written an alternative version: http://paste.pocoo.org/show/85699/ but, with a file of 315 MB, I have [1]: 1) map reduce implementation, non pa

Re: [Haskell-cafe] lazy strings and parallel read

manlio_perillo: > Hi. > > After having read > http://book.realworldhaskell.org/read/concurrent-and-multicore-programming.html#id676390 > > I have a doubt about Data.ByteString.Lazy. > > Why getContents function don't use pread (or an emulation, if not > available)? Why would it? -- Don __

[Haskell-cafe] ANNOUNCE: Extensible and Modular Generics for the Masses (EMGM) 0.1

Extensible and Modular Generics for the Masses == Extensible and Modular Generics for the Masses (EMGM) is a library for generic programming in Haskell using type classes. This is the initial release of a maintained library for EMGM. Other versions have

[Haskell-cafe] lazy strings and parallel read

Hi. After having read http://book.realworldhaskell.org/read/concurrent-and-multicore-programming.html#id676390 I have a doubt about Data.ByteString.Lazy. Why getContents function don't use pread (or an emulation, if not available)? Thanks Manlio Perillo

Re: [Haskell-cafe] Lazy vs correct IO [Was: A round of golf]

I agree that lazy IO is a can with some worms in it. But it's not that strange. The readFile operation is in the IO monad, so it has an effect on the world. This effect is not finished when readFile returns, and from the world point of view it's not entirely deterministic. On Fri, Sep 19, 2008 at

Re: [Haskell-cafe] Lazy vs correct IO [Was: A round of golf]

oleg-30 wrote: > > I have not expected to see this Lazy IO code. After all, what could be > more against > the spirit of Haskell than a `pure' function with observable side effects. > What could even be more against the spirit of Haskell than the original theme of this thread, i.e. code that

Re: [Haskell-cafe] control-timeout with gtk

Hello, Em Qui, 2008-09-18 às 10:05 -0700, Judah Jacobson escreveu: > Just a guess, but this might be a problem with control-timeout's use > of the unsafePerformIO global variables hack. It's missing the > standard NOINLINE annotations which prevent multiple copies of the > global variable from be

Re: [Haskell-cafe] control-timeout with gtk

Em Qui, 2008-09-18 às 16:14 -0300, Marco Túlio Gontijo e Silva escreveu: > Em Qui, 2008-09-18 às 11:51 -0700, Adam Langley escreveu: > > Do you want control-timeout? > > I think control-timeout is very useful. I'll try to fix it, and if I > could, I'll upload it to hackage then. I couldn't, and

Re: [Haskell-cafe] Lazy vs correct IO

[EMAIL PROTECTED] writes: > It is interesting to compare the above main function with the > corresponding lazy IO: Minor point I know, but aren't you really comparing it with the corresponding *strict* IO? > main'' = do >names <- getArgs >files <- mapM readFile names

[Haskell-cafe] Updated formlets sample?

Hi all, I found a blog post concerning formlets [1] in the web. Since looks very interesting I tried to compile the sample code with recent versions of HAppS and formlets from hackage. But this didn't work as the API of formlets has changed since this post. I tried to adopt the code to the n

Re: [Haskell-cafe] A round of golf

Don Stewart <[EMAIL PROTECTED]> writes: >> If I want to make my own efficient bytestring consumer, is that >> what I need to use in order to preserve the inherent laziness of >> the datastructure? > you can get foldChunks from Data.ByteString.Lazy.Internal, > or write your own chunk folder. IME

Re: [Haskell-cafe] A round of golf

"Creighton Hogg" <[EMAIL PROTECTED]> writes: > To ask an overly general question, if lazy bytestring makes a nice > provider for incremental processing are there reasons to _not_ reach > for that as my default when processing large files? I think it is a nice default. I'd reach for strict byte

[Haskell-cafe] Re: Library design question

Duncan Coutts wrote: > On Thu, 2008-09-18 at 15:43 -0300, Andre Nathan wrote: > >> My Graph type is the following. >> >> data Graph a b = Graph >> { adjacencies :: Map Int (a, (Map Int b)) >> , numVertices :: Int >> , numEdges:: Int >> } > >> addVertex :: Int -> a -> State

[Haskell-cafe] Re: Library design question

Andre Nathan wrote: > I'm trying to write a simple graph library for a project of mine There's also Martin Erwig's functional graph library in Data.Graph.Inductive ( fgl on hackage). Regards, apfelmus ___ Haskell-Cafe mailing list Haskell-Cafe@hask

Re: [Haskell-cafe] Lazy vs correct IO [Was: A round of golf]

oleg: > Given the stance against top-level mutable variables, I have not > expected to see this Lazy IO code. After all, what could be more against > the spirit of Haskell than a `pure' function with observable side > effects. With Lazy IO, one indeed has to choose between correctness > and perform