On 23 August 2010 14:03, Eugene Kirpichov ekirpic...@gmail.com wrote:
Do there exist other nontrivial higher-order algorithms and datastructures?
Is the field of higher-order algorithms indeed as unexplored as it seems?
Aren't higher order algorithms functional pearls? :-)
You might find
2010/8/24 Ivan Lazar Miljenovic ivan.miljeno...@gmail.com:
What do you mean by metapackages?
Metapackage are packages of packages, they don't provide something by
themselves, but they have a dependency list so that a set of package
can be installed together.
For example, on ubuntu, installing
On 24 August 2010 16:15, David Virebayre dav.vire+hask...@gmail.com wrote:
2010/8/24 Ivan Lazar Miljenovic ivan.miljeno...@gmail.com:
What do you mean by metapackages?
Metapackage are packages of packages, they don't provide something by
themselves, but they have a dependency list so that a
Here's a way I've been tinkering with to think about iteratees clearly.
For simplicity, I'll stick with pure, error-free iteratees for now, and take
chunks to be strings. Define a function that runs the iteratee:
runIter :: Iteratee a - [String] - (a, [String])
Note that chunking is explicit
2010/8/23 Christopher Done chrisd...@googlemail.com:
Any suggestions would be appreciated.
Isn't there the possibility to mute a thread in gmail ? You need to
activate keyboard shortcuts, then ? gives you a list of keys. m
seems to be used to mute a thread, but I didn't try it so I don't know
From: Daniel Fischer daniel.is.fisc...@web.de
To: 200901...@daiict.ac.in
Sent: Monday, August 23, 2010 11:14:55 PM
Subject: Re: [Haskell-cafe] Fast Integer Input
On Monday 23 August 2010 17:06:02 you wrote:
Does the length of those numbers happen to be fixed? It they are
all
exactly
On 8/24/10 12:29 AM, wren ng thornton wrote:
All of these are the same algorithm, just with different (augmented)
semirings. In order to prevent underflow for very small probabilities,
we usually run these algorithms with probabilities in the log-domain.
Those variants are also the same
Conal Elliott wrote:
Is there a simpler model of Enumerator? My intuition is that it's simply a
stream:
[[Enumerator a]] = String
Oddly, 'a' doesn't show up on the RHS. Maybe the representation ought to be
type Enumerator = forall a. Iteratee a - Iteratee a
so
[[Enumerator]] = String
On Tue, Aug 24, 2010 at 5:55 AM, Ivan Lazar Miljenovic
ivan.miljeno...@gmail.com wrote:
On 24 August 2010 15:50, Mathew de Detrich dete...@gmail.com wrote:
I used to use archlinux packages however it became a pain for the
following
reasons
- packages on archlinux don't auto update when
Jason Dagit wrote:
From a purely practical viewpoint I feel that treating the chunking
as an abstraction leak might be missing the point. If you said, you
wanted the semantics to acknowledge the chunking but be invariant
under the size or number of the chunks then I would be happier.
I use
On Mon, Aug 23, 2010 at 11:41 PM, wren ng thornton w...@freegeek.org wrote:
I believe the denotation of an iteratee is the transition function for an
automaton (or rather a transducer). I hesitate to speculate on the specific
kind of automaton without thinking about it, so maybe finite, maybe
On Tue, Aug 24, 2010 at 12:49 AM, Heinrich Apfelmus
apfel...@quantentunnel.de wrote:
Jason Dagit wrote:
From a purely practical viewpoint I feel that treating the chunking
as an abstraction leak might be missing the point. If you said, you
wanted the semantics to acknowledge the chunking
On Tue, Aug 24, 2010 at 06:50, Mathew de Detrich dete...@gmail.com wrote:
I used to use archlinux packages however it became a pain for the following
reasons
- packages on archlinux don't auto update when cabal does. This becomes
really annoying when package X gets updated on cabal but not on
On Tue, Aug 24, 2010 at 2:48 AM, David Virebayre
dav.vire+hask...@gmail.com wrote:
2010/8/23 Christopher Done chrisd...@googlemail.com:
Any suggestions would be appreciated.
Isn't there the possibility to mute a thread in gmail ? You need to
activate keyboard shortcuts, then ? gives you a
Thanks, that was helpful :) here is the working code if someone
interested: http://hpaste.org/fastcgi/hpaste.fcgi/view?id=29406#a29406
2010/8/24 wren ng thornton w...@freegeek.org:
Vladimir Matveev wrote:
I'm trying to implement the Advanced Example : Type-Level Quicksort
from HaskellWiki
On Mon, Aug 23, 2010 at 6:10 PM, Max Rabkin max.rab...@gmail.com wrote:
(Accidentally sent off-list, resending)
On Mon, Aug 23, 2010 at 15:03, Eugene Kirpichov ekirpic...@gmail.com
wrote:
* Difference lists
I mean that not only higher-order facilities are used, but the essence
of the
Hi,
Am Dienstag, den 24.08.2010, 09:30 +0100 schrieb Magnus Therning:
On Tue, Aug 24, 2010 at 06:50, Mathew de Detrich dete...@gmail.com wrote:
- in some situations doing a general update with arch (through clyde or
packer) breaks ghc (last time it happened packer tried to uninstall/update
Thomas DuBuisson wrote:
[1]
http://tommd.wordpress.com/2010/08/23/a-haskell-api-for-cryptographic-algorithms/
class (Binary p, Serialize p) = AsymCipher p where
generateKeypair :: RandomGen g = g - BitLength - Maybe ((p,p),g)
encryptAsym :: p - B.ByteString - B.ByteString
From: C. McCann c...@uptoisomorphism.net
What sets an iteratee-style design apart from something conventional
based on a State monad is that the iteratee conceals its internal
state completely (in fact, there's no reason an iteratee even has to
be the same function step-to-step, or have a
From: Magnus Therning mag...@therning.org
On 24/08/10 03:47, John Millikin wrote:
[...]
I would like to avoid hard-coding the error type to SomeException,
because
it forces libraries to use unsafe/unportable language features (dynamic
typing and casting). However, given the apparent
Anyone in the Haskell community interested in content-centric
networking? Van Jacobson has done a couple of great presentations to
introduce CCN [1, 2]. Personally, I find it fascinating what kind of
doors could open if we got away from TCP/IP, especially for wireless
ad-hoc networking.
Parc
I think the big problem with chunking is that many useful iteratees need to
be able to inspect the length of the chunk. The most obvious is drop, but
there are many others. Or if not inspect the length, have a new function on
the stream dropReport :: Int - s - (s, Int) which reports how much was
Hi John,
Please note that I'm suggesting eliminating chunks from the semantics only
-- not from the implementation.
For precise simple chunk-less semantics, it's only important that the
iteratees map equivalent input streams to equivalent output streams, where
equivalent means equal after
On 24 August 2010 13:00, John Lato jwl...@gmail.com wrote:
This is how I think of them. I particularly your description of them as a
foldl with a pause button.
Maybe it would be helpful to consider iteratees along with delimited
continuations?
Aren't they closer - in implementation and by
On Tue, Aug 24, 2010 at 12:18, Joachim Breitner
m...@joachim-breitner.de wrote:
Hi,
Am Dienstag, den 24.08.2010, 09:30 +0100 schrieb Magnus Therning:
On Tue, Aug 24, 2010 at 06:50, Mathew de Detrich dete...@gmail.com wrote:
- in some situations doing a general update with arch (through clyde
Hi,
I am trying to build a mini framework for image processing but I can find
any examples about that (bitmap processing ). Does anybody know were can I
find some tutorials or samples about that ?
Regards,
Raluca-Elena
___
Haskell-Cafe mailing list
Interesting. I've come across this general idea/algorithm the factor graph /
sum-product algorithm papers[1] but I was wondering if you knew of any
implementations of it in haskell? I wrote one a while back but it was fairly
ugly and not as general as I'd have liked, so I never released it.
Hi Conal,
I'm aware of one case that violates semantic referential transparency, but
it's a bug. Which pretty much proves your point as I understand it.
John
On Tue, Aug 24, 2010 at 2:01 PM, Conal Elliott co...@conal.net wrote:
Hi John,
Please note that I'm suggesting eliminating chunks
From: Stephen Tetley stephen.tet...@gmail.com
On 24 August 2010 13:00, John Lato jwl...@gmail.com wrote:
This is how I think of them. I particularly your description of them as
a
foldl with a pause button.
Maybe it would be helpful to consider iteratees along with delimited
Automatic differentiation can also bee seen this way. In a sense it
transforms a function to compute f(x) into a function to compute
f'(x), where f' is the derivative of f.
--
Dan
On Mon, Aug 23, 2010 at 6:03 AM, Eugene Kirpichov ekirpic...@gmail.com wrote:
Most of the well-known algorithms are
John Lato jwl...@gmail.com writes:
Oleg included the error state to enable short-circuiting of
computation, and I guess everyone just left it in. Recently I've been
wondering if it should be removed, though, in favor requiring explicit
(i.e. explicit in the type sig) exceptions for
Eugene Kirpichov wrote:
Most of the well-known algorithms are first-order, in the sense that
their input and output are plain data.
Some are second-order in a trivial way, for example sorting,
hashtables or the map and fold functions: they are parameterized by a
function, but they don't really
On Wed, Aug 18, 2010 at 9:56 PM, wren ng thornton w...@freegeek.org wrote:
Oleg Lobachev wrote:
#ifdef USE_REPORT_PRELUDE
and = foldr () True
or = foldr (||) False
#else
and [] = True
and (x:xs) = x and xs
or [] =
The function image style always described as from Point to ...
[insert Picture, Bitmap, Texture...] is also inherently higher order.
Examples are Conal Elliott's Pan, Jerzy Karczmarczuk's Clastic and
Peter Henderson's images.
In Clastic and Pan, the higher order image seems like a characteristic
On Tue, Aug 24, 2010 at 7:16 PM, Gregory Collins g...@gregorycollins.netwrote:
John Lato jwl...@gmail.com writes:
Oleg included the error state to enable short-circuiting of
computation, and I guess everyone just left it in. Recently I've been
wondering if it should be removed, though,
On Tue, Aug 24, 2010 at 11:02 AM, Raluca-Elena Podiuc
ralucaelena1...@gmail.com wrote:
Hi,
I am trying to build a mini framework for image processing but I can find
any examples about that (bitmap processing ). Does anybody know were can I
find some tutorials or samples about that ?
Noam
On Tue, Aug 24, 2010 at 05:12, John Lato jwl...@gmail.com wrote:
Oleg included the error state to enable short-circuiting of computation, and
I guess everyone just left it in. Recently I've been wondering if it should
be removed, though, in favor requiring explicit (i.e. explicit in the type
On Tue, Aug 24, 2010 at 11:44 AM, John Lato jwl...@gmail.com wrote:
Aren't they closer - in implementation and by supported operations -
to resumptions monads?
See many papers by William Harrison here:
http://www.cs.missouri.edu/~harrisonwl/abstracts.html
I'm not familiar with resumption
Sifflet-lib 1.1 and sifflet 1.1 are now available on Hackage.
Sifflet is a visual, functional programming language
and support system for students learning about recursion.
Sifflet programmers define functions by drawing diagrams,
and the Sifflet interpreter uses diagrams to show how the
function
Here's my (uneducated, half-baked) two cents:
There's really no need for an Iteratee type at all, aside from the
utility of defining Functor/Monad/etc instances for it. The core type
is step, which one can define (ignoring errors) as:
data Step a b = Continue (a - Step a b)
Thanks for taking a look - I've never got round to investigating the
connection properly but have noticed the strong similarity between the
data type defintions of the ResT and Iteratee.
William Harrison makes the interesting point in the Cheap Threads
papers that by itself the resumption monad
Hi everyone,
Here's some code that's giving me an error message I don't understand:
{-# LANGUAGE EmptyDataDecls,
MultiParamTypeClasses,
UndecidableInstances,
FlexibleInstances #-}
data Z
data S n
class Nat n where
toInt :: n - Int
instance Nat Z
On 8/24/10 1:54 PM, Bartek Æwik³owski wrote:
Hello Michael,
This is because instance selection is solely based on instance heads,
it doesn't consider contexts. There's a nice explanation available
here: http://www.haskell.org/haskellwiki/GHC/AdvancedOverlap
The fix in this case is very easy
On Tue, Aug 24, 2010 at 4:42 PM, Michael Vanier mvanie...@gmail.com wrote:
Adding OverlappingInstances to the language pragmas fixes the problem. My
question is: why is this an overlapping instance? It would make sense if
Int was an instance of Nat, but it isn't. Is this just a limitation in
On Aug 22, 2010, at 7:34 PM, Jesse Schalken wrote:
I would also like to strongly discourage code generators.
I've used ad hoc code generators a lot, and never had
reason to regret it.
The key point is that ALL maintenance of the generated code
must be done by maintaining the generator and its
In that case do you also need fast insert and delete? I think both a
pure functional cons list and a pure functional skip list take O(N) to
insert an element or remove an element at position N (because you have
to re-cons the elements in front of it). Also do suffixes need to
also be lists?
In the past I've taken a hybrid approach - ad-hoc fixes are done to the
generated code, but it is done via 'patch' as an automated step, and the
diff is stored in source control with everything else.
You'll need extra tool support to build the diff, as well.
It's still really brittle, and I
Quoth Richard O'Keefe o...@cs.otago.ac.nz,
...
Of course code generation is perfectly fine when the output is not
intended to be read and maintained by a human.
Read and maintained are two different issues.
Depending on the tool-chain, it may be necessary for people to
read the generated
On 24 August 2010 17:45, Mathew de Detrich dete...@gmail.com wrote:
On Tue, Aug 24, 2010 at 5:55 AM, Ivan Lazar Miljenovic
ivan.miljeno...@gmail.com wrote:
On 24 August 2010 15:50, Mathew de Detrich dete...@gmail.com wrote:
- packages on archlinux don't auto update when cabal does. This
On 24 August 2010 21:18, Joachim Breitner m...@joachim-breitner.de wrote:
Hi,
Am Dienstag, den 24.08.2010, 09:30 +0100 schrieb Magnus Therning:
On Tue, Aug 24, 2010 at 06:50, Mathew de Detrich dete...@gmail.com wrote:
- in some situations doing a general update with arch (through clyde or
On 25 August 2010 07:51, Richard O'Keefe o...@cs.otago.ac.nz wrote:
On Aug 22, 2010, at 7:34 PM, Jesse Schalken wrote:
Every software project which I've worked on that used a code generator
turned into a nightmare, because when we find we need to change
something about the generator's
On Aug 22, 2010, at 3:41 AM, Andrew Coppin wrote:
It looks as if it's automated for Arch, however. Either that or
somebody is spending an absurd amount of time keeping it manually up
to date.
It probably is automated. There's a tool out there called
cabal2arch, which turns a cabal file
On Wed, Aug 25, 2010 at 12:07 PM, Alexander Solla a...@2piix.com wrote:
On Aug 22, 2010, at 3:41 AM, Andrew Coppin wrote:
It looks as if it's automated for Arch, however. Either that or somebody
is spending an absurd amount of time keeping it manually up to date.
It probably is
On 8/24/10 11:10 AM, Daniel Peebles wrote:
Interesting. I've come across this general idea/algorithm the factor graph /
sum-product algorithm papers[1] but I was wondering if you knew of any
implementations of it in haskell? I wrote one a while back but it was fairly
ugly and not as general as
On 25 August 2010 14:36, Mathew de Detrich dete...@gmail.com wrote:
On Wed, Aug 25, 2010 at 1:59 PM, Ivan Lazar Miljenovic
ivan.miljeno...@gmail.com wrote:
Consider these scenarios:
1) You upgrade package foo; this breaks a large number of other
packages. How do you deal with it?
Thats
On 8/24/10 3:54 AM, C. McCann wrote:
What sets an iteratee-style design apart from something conventional
based on a State monad is that the iteratee conceals its internal
state completely (in fact, there's no reason an iteratee even has to
be the same function step-to-step, or have a single
On 8/24/10 1:55 PM, Jan-Willem Maessen wrote:
On Wed, Aug 18, 2010 at 9:56 PM, wren ng thorntonw...@freegeek.org wrote:
The thing I find puzzling is that the foldr is inlined. The (regular) clever
optimizations for build/foldr seem like they should already handle this
without the need for the
In all honesty I think the issue is that archlinux AUR packages are being
generated in a very naive way (and not a Archlinux philosophy in general).
The whole point of AUR is that its supposed to make it very easy for people
to upload packages/libraries.
In my opinion putting such packages in AUR
On 25/08/10 06:18, Mathew de Detrich wrote:
[...]
If people just wanted an auto udpate version of cabal that works through
arch's package management, then there should have just been a pacman wrapper
which when you install/update haskell libraries/packages, it creates a local
package through
On 8/24/10 5:12 PM, C. McCann wrote:
The problem is that instance selection doesn't work the (obvious,
seemingly-sensible) way you thought it did. In short, instance
contexts are only examined after the fact;
[...]
The reason it works this way has to do with the nature of type classes
being
Oh thanks
3
On Wed, Aug 25, 2010 at 3:21 PM, Magnus Therning mag...@therning.orgwrote:
On 25/08/10 06:18, Mathew de Detrich wrote:
[...]
If people just wanted an auto udpate version of cabal that works through
arch's package management, then there should have just been a pacman
wrapper
deteego:
If people just wanted an auto udpate version of cabal that works through
arch's
package management, then there should have just been a pacman wrapper which
when you install/update haskell libraries/packages, it creates a local package
through cabal2arch instead of using AUR.
I am looking for an example of dealing with a 2dim mem region with O1
access time in pure haskell (pure as in whatever comes with haskell
platform).
On Tue, Aug 24, 2010 at 11:59 PM, Anthony Cowley acow...@seas.upenn.edu wrote:
On Tue, Aug 24, 2010 at 11:02 AM, Raluca-Elena Podiuc
You just need to use STUArray .
2010/8/25 C K Kashyap ckkash...@gmail.com:
I am looking for an example of dealing with a 2dim mem region with O1
access time in pure haskell (pure as in whatever comes with haskell
platform).
On Tue, Aug 24, 2010 at 11:59 PM, Anthony Cowley
64 matches
Mail list logo
