[Haskell-cafe] Re: HList error with hFoldr

Denis Bueno wrote: > For the moment my HLists only contain Ints. ... > -- Why should the following generate an error? > testApplyDistSum = hFoldr ApplyDistSum 0 ((4,4) .*. hNil) Here is the problem: in Haskell, 4 is not an Int. (4::Int) is an Int, but just 4 is a _polymorphic_ constant of the ty

[Haskell-cafe] running into an unresolved linker error on RHEL 5

Hello, I am building the unix-2.2.0.0. The linker is failing with -lgmp. I set "export LD_LIBRARY_ATH=/bin:/usr/lib". I did a "ls -l /usr/lib/*gmp*" and I can see: libgmp.so.3 libgmp.so.3.3.3 libgmpxx.so.3 libgmpxx.so.3.0.5, i.e. either gmp shared objects and whatever the gmp "xx" shared obj

[Haskell-cafe] ANN: bytestringparser-0.2, a Parsec-like parser for lazy ByteStrings

Some time ago, Jeremy Shaw wrote a Parsec clone for lazy ByteStrings. I've been using it for a while, and have made substantial changes to it along the way. It's very fast, using the same manual unpacking trick as the binary package to keep performance nippy. It also integrates with the latest fl

[Haskell-cafe] HList error with hFoldr

Hello all, I'm doing some machine learning in Haskell and have run into a problem. I have a generic distance function (declare in the MetricSpace) typeclass that returns the distance between two things as a number. I frequently will be working with heterogeneous collections of data, and if possi

Re: [Haskell-cafe] Re: Why functional programming matters

Am Freitag, 25. Januar 2008 03:35 schrieb Conal Elliott: > […] > See http://haskell.org/haskellwiki/Reactive and http://haskell.org/yampa/ . Or better which has come into existence recently. > […] Best wishes, Wolfgang __

Re: [Haskell-cafe] Internships at GHC HQ

On 1/25/08, Dan Licata <[EMAIL PROTECTED]> wrote: > A further plug: > > I did an internship with Simon PJ last summer (implementing view > patterns in GHC, among other things), and this is a great opportunity if > you're interested in PL research. There is a lot of interesting work > going on at M

[Haskell-cafe] Re: hxt memory useage

"Matthew Pocock" <[EMAIL PROTECTED]> schrieb im Newsbeitrag news:[EMAIL PROTECTED] > On Thursday 24 January 2008, Albert Y. C. Lai wrote: >> Matthew Pocock wrote: >> > I've been using hxt to process xml files. Now that my files are getting >> > a >> > bit bigger (30m) I'm finding that hxt uses in

[Haskell-cafe] NDP

Hi all, is someone familiar with compiling ndp (nested data parallel Haskell), "Speed with less convenience"-version? I followed the guide at http://www.haskell.org/haskellwiki/Data_Parallel_Haskell/PackageNDP but executing "make" in the examples directory issues the following error: (.tex

Re: [Haskell-cafe] hxt memory useage

ketil+haskell: > Matthew Pocock <[EMAIL PROTECTED]> writes: > > > I've been using hxt to process xml files. Now that my files are getting a > > bit > > bigger (30m) I'm finding that hxt uses inordinate amounts of memory. > : > > Is this a known issue? > > Yes. I parse what I suppose are rath

[Haskell-cafe] Re: [darcs-devel] announcing darcs 2.0.0pre3

On Wed, Jan 23, 2008 at 03:26:51PM +, Simon Marlow wrote: > There are still times when I see nothing happening, for example in the > unpull test on the GHC repo (see previous messages), the last progress > message I get is > > Reading patches in /64playpen/simonmar/ghc-darcs2 17040 > > and

Re: [Haskell-cafe] Internships at GHC HQ

A further plug: I did an internship with Simon PJ last summer (implementing view patterns in GHC, among other things), and this is a great opportunity if you're interested in PL research. There is a lot of interesting work going on at MSR Cambridge, the atmosphere is very friendly, and Cambridge

Re: [Haskell-cafe] realtime garbage collector for ghc (was: Why functional programming matters)

See also A parallel, real-time garbage collector Perry Cheng and Guy Blelloch PLDI 2001 This was implemented in the TILT compiler for SML (which, to be fair, is more of a research vehicle than a programmer-friendly implementation). -Dan On Jan25, Stefan Kersten wrote: > On 25.01.2008, at

Re: [Haskell-cafe] realtime garbage collector for ghc

Hi Stefan, A real time incremental gc would be really cool. Some people claim they exist, but which languages have one? james mccartney's supercollider [1] has a non-copying incremental collector based on [2], though not a parallel one. btw, is an implementation of the incremental collecto

Re: [Haskell-cafe] Internships at GHC HQ

On 25/01/2008, Simon Peyton-Jones <[EMAIL PROTECTED]> wrote: > Would you be interested in working at Microsoft Research for three months? > If so, you might want to think about applying for an internship. > I would love to! But here are some questions: 1. Do I _necessarily_ have to come to MSR

[Haskell-cafe] realtime garbage collector for ghc (was: Why functional programming matters)

On 25.01.2008, at 00:04, Evan Laforge wrote: Well... ghc still has a single-threaded garbage collector, so all the "par" threads must stop for garbage collection. So scaling to the level of a cluster would be significantly sub-linear. A real time incremental gc would be really cool. Some peop

Re: [Haskell-cafe] Evolutionary Computing

Dusan Kolar wrote: Hello, I don't know about math, but a practical usage seems to be in the reconfigurable hardware (FPGA). See web-page of my colleague, where is list of his papers on the topic. http://www.fit.vutbr.cz/~sekanina/pubs.php These people use GAs for optimising water networks (a

Re: [Haskell-cafe] Evolutionary Computing

Hello, I don't know about math, but a practical usage seems to be in the reconfigurable hardware (FPGA). See web-page of my colleague, where is list of his papers on the topic. http://www.fit.vutbr.cz/~sekanina/pubs.php Dusan PR Stanley wrote: Hi What does the list think of EC? Genetic alg

Re: [Haskell-cafe] hxt memory useage

Hi One of the problems with XML parsing is nesting. Consider this fragment: lots of text The parser will naturally want to track all the way down to the closing in order to check the document is well formed, so it can put it in a tree. The problem is that means keeping "lots of text" in memory

Re: [Haskell-cafe] Why functional programming matters

Yaakov Nemoy wrote: I'm still very much a newbie, but the one thing that struck me as the best feature coming from Python is the static typing. Changing the type of a function in Python will lead to strange runtime errors that take some work to debug, whereas, when I tinker with a program in Ha

Re: [Haskell-cafe] Fwd: ByteString Parsec clone

> legally, since it's released under BSD, you're allowed to do all that > (as long as you don't delete the bit of attribution that the BSD > requires :-) As a practical matter. How do you manage attributions. Can you put a other-project.LICENSE file which is a copy of the other projects LICENSE fi

Re: [Haskell-cafe] hxt memory useage

Matthew Pocock <[EMAIL PROTECTED]> writes: > I've been using hxt to process xml files. Now that my files are getting a bit > bigger (30m) I'm finding that hxt uses inordinate amounts of memory. : > Is this a known issue? Yes. I parse what I suppose are rather large XML files (the largest so f

Re: [Haskell-cafe] Fwd: ByteString Parsec clone

Johan Tibell wrote: I tried to get Dan's thoughts on cloning parts of the Parsec interface and some of the documentation but none of the emails addresses I've tried seem to work. What's allowed when it comes to duplicating something like an API? What about the documentation? I intend it to be rel

[Haskell-cafe] Internships at GHC HQ

Would you be interested in working at Microsoft Research for three months? If so, you might want to think about applying for an internship. Simon and I are looking for interns, starting in summer 2008. Lots of background info here: http://hackage.haskell.org/trac/ghc/wiki/Internships i

Re: [Haskell-cafe] Re: cryptographic hash functions in darcs (re: announcing darcs 2.0.0pre3)

* zooko wrote: > This makes the choice of SHA-1 for the patch-id-generation function > wholly inappropriate. We already know that SHA-1 doesn't have > collision resistance, and there is reason to suspect that in the near > future it will turn out that it doesn't have second-pre-image > res

[Haskell-cafe] Fwd: ByteString Parsec clone

I tried to get Dan's thoughts on cloning parts of the Parsec interface and some of the documentation but none of the emails addresses I've tried seem to work. What's allowed when it comes to duplicating something like an API? What about the documentation? I intend it to be released under BSD3 which

[Haskell-cafe] Re: Why functional programming matters

Simon Peyton-Jones wrote: 1. Small examples of actual code. I particularly like the lazy way of counting change example (also works for picking items off a menu). The code below show 3 approaches : a function for computing the coins used in each way as a verbose list a function for computi

Re: [Haskell-cafe] parsec and bytestring; was: hxt memory useage

On Jan 24, 2008 10:34 PM, Matthew Pocock <[EMAIL PROTECTED]> wrote: > Would a bytestring-backed implementation of parsec solve my problems? Is there > such a beast out there? I'm working on one as a part of another project. It's not incremental and needs some optimizing (I've focused on correctnes