On Sun, Jul 25, 2010 at 11:53 PM, Edward Z. Yang ezy...@mit.edu wrote:
An interesting alternate spin on flip is infix notation combined with partial
application, such as:
(`foobar` 3)
which is equivalent to
\x - foobar x 3
I frequently use this, although the jury's out on whether
On 26 July 2010 16:33, David Virebayre dav.vire+hask...@gmail.com wrote:
On Sun, Jul 25, 2010 at 11:53 PM, Edward Z. Yang ezy...@mit.edu wrote:
An interesting alternate spin on flip is infix notation combined with partial
application, such as:
(`foobar` 3)
which is equivalent to
\x
On 26 jul 2010, at 03:51, Jason Dagit wrote:
Hello,
I find that parser correctness is often hard to verify. Therefore, I'm
interested in techniques that others have used successfully, especially with
Haskell.
It seems to me that you are not so much trying to verify parsers, but more
On Mon, Jul 26, 2010 at 12:03 AM, S. Doaitse Swierstra
doai...@swierstra.net wrote:
On 26 jul 2010, at 03:51, Jason Dagit wrote:
Hello,
I find that parser correctness is often hard to verify. Therefore, I'm
interested in techniques that others have used successfully, especially with
On Sun, Jul 25, 2010 at 23:47, Lally Singh lally.si...@gmail.com wrote:
Hey all,
This is on OpenSolaris. Simple attempts to build cabal packages
give me this error, and I don't know what it means. Here's an
example:
[07/25 18:51::la...@sol type-level]$ runghc Setup.hs configure
Richard,
I'm not sure that I agree or disagree with you; I think the decision
is above my pay grade.
On Mon, Jul 26, 2010 at 4:49 AM, Richard O'Keefe o...@cs.otago.ac.nz wrote:
On Jul 26, 2010, at 12:35 PM, John Lato wrote:
Incidentally, there seems to be a consensus that this a Bad Idea [1].
On 25/07/10 21:55, Yves Parès wrote:
Hello !
I've been studying Erlang and Scala, and I was wondering if someone
has already implemented an actors and message passing framework for
concurrent and distributed programs in Haskell.
Hi,
Take a look at the concurrency section on Hackage:
Hi Jason
Which particular file in the Darcs tree defines the parser?
Small adhoc formats don't necessarily have a simple underlying
grammar, even though a parser for them might not have many
productions. A hand-crafted parser for such a format might often be
context-sensitive, or do clever
On Mon, Jul 26, 2010 at 03:01:54 +, Jason Dagit wrote:
I think the grammar is fairly simple, although I'm not confident classifying
it. I know it can be parsed with just a simple pass over the data. The
only uses of backtracking are just to figure out what is next, like a peek
at the
| Data.Map.Map and Data.Set.Set are exported abstractly, without
| exposing knowledge about their internal structure.
|
| I cannot directly create my own class instances for them because of
| that. But I found that I can write Template Haskell code that could do
| that - those data types
By the way, it is easy to implement selective receive using
first-class-patterns (this is the package's name, IIRC).
2010/7/26 Neil Brown nc...@kent.ac.uk:
On 25/07/10 21:55, Yves Parčs wrote:
Hello !
I've been studying Erlang and Scala, and I was wondering if someone has
already
I took a quick look at this file. To me it seems a mixture of a lexer and a
parser built on top of a home brewn parser library. I see function like
maybeWork which
(if I interpret correctly) test whether specific conditions hold for the input,
etc.
Indeed it would be nice to have a
Hi,
I don't know if this solves your problem, but maybe you should take a look
at the Holumbus-Distribution package:
http://hackage.haskell.org/package/Holumbus-Distribution
I've build this library because I needed a simple way to transfer messages
between two haskell processes or threads.The
I find it useful to have a seed argument to nearly all random
functions rather than using ones with an IO signature. This way you
can speed up your program quite a bit and also make testing much
easier. I think that MonadRandom does this automatically too.
As a Haskell neophyte, one of the things I find confusing is the way
that the usual list functions (map, fold, ++, etc.) often cannot be
used directly with monadic lists (m [a] or [m a]) but seem to require
special purpose functions like ap, mapM etc.
I get the idea of separating pure and impure
2010/7/26 Kevin Jardine kevinjard...@gmail.com:
As a Haskell neophyte, one of the things I find confusing is the way
that the usual list functions (map, fold, ++, etc.) often cannot be
used directly with monadic lists (m [a] or [m a]) but seem to require
special purpose functions like ap, mapM
2010/7/26 Kevin Jardine kevinjard...@gmail.com:
I suspect that things are not quite as difficult as they appear,
however, but cannot find any tutorials on monadic list manipulation.
I'd suggest that you get as many pure values as possible from impure
world, apply to them easy to use pure
I think most of the Erlang style actors with message passing can be done in
Haskell with just TChan and forkIO.
http://en.wikibooks.org/wiki/Haskell/Concurrency
- Job
On Sun, Jul 25, 2010 at 4:55 PM, Yves Parès limestr...@gmail.com wrote:
Hello !
I've been studying Erlang and Scala, and I
On Sun, Jul 25, 2010 at 11:39 AM, michael rice nowg...@yahoo.com wrote:
Hi All,
From: http://en.wikibooks.org/wiki/Haskell/Understanding_monads/State
Exercises
1. Implement a function rollNDiceIO :: Int - IO [Int] that,
given an integer, returns a list
On Jul 26, 3:00 pm, Vo Minh Thu not...@gmail.com wrote:
Also, just like with IO, maybe restructuring the code to separate
monadic code would help.
The specific monad I am dealing with carries state around inside it.
I could revert to a pure system in many cases by simply passing the
state as
Hi,
I'm stuck at page 151 of Real World Haskell and hoping that perhaps some
of you can give me a hand here...
The code that is giving me trouble is below.
data JValue = JString String
| JNumber Double
| JBool Bool
| JNull
| JObject [(String,
2010/7/26 Kevin Jardine kevinjard...@gmail.com:
On Jul 26, 3:00 pm, Vo Minh Thu not...@gmail.com wrote:
Also, just like with IO, maybe restructuring the code to separate
monadic code would help.
The specific monad I am dealing with carries state around inside it.
I could revert to a pure
On Jul 26, 3:19 pm, Vo Minh Thu not...@gmail.com wrote:
Maybe you missed the part of my answer hinting to applicative style?
No, I saw that but as I mentioned, I am looking for a tutorial. The
source code alone means little to me.
LYAH has a chapter about it[0].
Thanks for the pointer. I
Can you post an example of your code? mapM and map are actually for pretty
distinct purposes.
If you find yourself wanting to map over a pure list in monadic code, you
should really look at applicative style, e.g.:
import Control.Applicative
data Struct = deriving (Read)
Hi all,
I want to open a Haskell forum based on phpBB, but I need some collaborators
for organize its content, and moderate its use. When we have finished, I
will open this forum for the entire community of Haskell!
If you are interested, mail me:
danield...@asofilak.es
Thanks in advance.
In fact, I noticed Holumbus.
You say that With the help of this library it is possible to build
Erlang-Style mailboxes, but how would you solve the issue of static typing?
Besides, Holumbus depends on package 'unix', preventing it from being used
on non-unix platforms.
2010/7/26 Stefan Schmidt
2010/7/26 Daniel Díaz lazy.dd...@gmail.com:
Hi all,
I want to open a Haskell forum based on phpBB, but I need some collaborators
for organize its content, and moderate its use. When we have finished, I
will open this forum for the entire community of Haskell!
Hi,
The idea of a forum has
On Jul 26, 3:26 pm, Bill Atkins watk...@alum.rpi.edu wrote:
Can you post an example of your code?
Without getting into the complexities, one simple example is a fold
where the step function returns results in a monad.
I have taken to replacing the fold in that case with a recursive
function,
How about:
*Main fromJValue (JBool True) :: Either JSONError Bool
Right True
*Main
Doaitse
On 26 jul 2010, at 15:16, Angel de Vicente wrote:
data JValue = JString String
| JNumber Double
| JBool Bool
| JNull
| JObject [(String, JValue)]
Hello,
On Jul 13, 2010, at 9:15 AM, Andy Stewart wrote:
Please report any bug of gtk2hs-0.11.0, we will fix it before release
gtk2hs-0.11.1
I have just installed the new Haskell Platform under Mac OS X 10.5.
With the previous installation of GHC 6.10.4 I managed to install
gtk2hs
Well, I thought that it may be a more comfortable way to communicate between
us. Specially for newcomers. Don't forget that Haskell is a growing
community.
It's just my opinion.
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Hi Lyndon,
Since the example immediately above the exercise used randomRIO, I assumed that
randomRIO was to be used as part of the solution to the exercise.
http://en.wikibooks.org/wiki/Haskell/Understanding_monads/State
Also, it was the above mentioned example that introduced me to *liftM2*,
On Monday 26 July 2010 15:16:36, Angel de Vicente wrote:
Hi,
I'm stuck at page 151 of Real World Haskell and hoping that perhaps some
of you can give me a hand here...
The code that is giving me trouble is below.
data JValue = JString String
| JNumber Double
|
On Jul 26, 3:49 pm, Kevin Jardine kevinjard...@gmail.com wrote:
I find
myself wishing that f (m [a]) just automatically returned m f([a])
without me needing to do anything but I expect that there are reasons
why that is not a good idea.
Or is there a monadic list module where f(m [a]) = m f
The answer is still applicative. :)
On Monday Jul 26, 2010, at 10:06 AM, Kevin Jardine wrote:
On Jul 26, 3:49 pm, Kevin Jardine kevinjard...@gmail.com wrote:
I find
myself wishing that f (m [a]) just automatically returned m f([a])
without me needing to do anything but I expect that there
On Jul 26, 4:12 pm, Bill Atkins watk...@alum.rpi.edu wrote:
The answer is still applicative. :)
OK, then I know where to spend my reading time.
Thanks!
Kevin
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I agree. A web forum would be more friendly to newcomers, easier to browse,
and better organized, than the mailing list.
Some people will still prefer the mailing list of course, but I think there
will be enough demand to justify a forum :)
- Job
On Mon, Jul 26, 2010 at 9:57 AM, Daniel Díaz
On 10:37 Mon 26 Jul , Job Vranish wrote:
I agree. A web forum would be more friendly to newcomers, easier to browse,
and better organized, than the mailing list.
I don't understand this sentiment at all. How are web forums easier to
browse than list archives? Especially given that there
I agree with prior discussion on this list that adding contexts to
datatype declarations seems to be more trouble than its worth, since
these contexts just have to be added again to every function using the
datatype. However, I have often wondered: why do function *have* to
have these
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On 7/26/10 06:02 , John Lato wrote:
If the behavior of class contexts on data types were changed to what
you think it should mean, i.e. contexts specified in a data
declaration are carried around for all uses of that type instead of
just the data
On Mon, Jul 26, 2010 at 15:47, Nick Bowler nbow...@elliptictech.com wrote:
On 10:37 Mon 26 Jul , Job Vranish wrote:
I agree. A web forum would be more friendly to newcomers, easier to browse,
and better organized, than the mailing list.
I don't understand this sentiment at all. How are
Other topics I am interested in are served by both a web forum and a
mailing list, usually with different content and participants in both.
In my experience, routing one kind of content to another does not work
very well because of issues of spam control, moderation, topic
subdivisions, the
Hello,
this year's ICFP features A Play on Regular Expressions where two
Haskell programmers and an automata theory guru develop an efficient
purely functional algorithm for matching regular expressions.
A Haskell library based on their ideas is now available from Hackage.
For more
Hi Max,
How about this function?
processFiles :: IterateeG [] String m a - [FilePath] - m
(IterateeG [] String m a)
processFiles = foldM (\i fp - fileDriver fp (convStream decodeStrings i)
The nice thing about an enumeratee is that you can just run the outer
iteratee (fileDriver does
From: Kevin Jardine kevinjard...@gmail.com
As a Haskell neophyte, one of the things I find confusing is the way
that the usual list functions (map, fold, ++, etc.) often cannot be
used directly with monadic lists (m [a] or [m a]) but seem to require
special purpose functions like ap, mapM
Hello,
I was wondering today, is this generally true?
instance (Monad m, Monoid a) = Monoid (m a) where
mempty = return mempty
mappend = liftM2 mappend
I know it isn't a good idea to use this instance, but assuming that
the instance head does what I mean, is it valid? Or more generally is
On Mon, Jul 26, 2010 at 11:55 AM, John Lato jwl...@gmail.com wrote:
Hello,
I was wondering today, is this generally true?
instance (Monad m, Monoid a) = Monoid (m a) where
mempty = return mempty
mappend = liftM2 mappend
Yes.
I know it isn't a good idea to use this instance, but
On 08:15 Mon 26 Jul , Kevin Jardine wrote:
Other topics I am interested in are served by both a web forum and a
mailing list, usually with different content and participants in both.
In my experience, routing one kind of content to another does not work
very well because of issues of spam
Sebastian Fischer s...@informatik.uni-kiel.de writes:
Hello,
On Jul 13, 2010, at 9:15 AM, Andy Stewart wrote:
Please report any bug of gtk2hs-0.11.0, we will fix it before release
gtk2hs-0.11.1
I have just installed the new Haskell Platform under Mac OS X 10.5. With the
previous
On Sun, Jul 25, 2010 at 1:53 PM, Alexey Karakulov ankaraku...@gmail.com wrote:
Suppose I have one piece of code like this:
class Result r e | r - e where
failure :: e - r a
success :: a - r a
Maybe instance is discarding failure information:
instance Result Maybe e where
I'd only really go on a Haskell forum hosted at haskell.org. If there
wlil be one, I'd moderate. Only things a forum has over a mailing list
is syntax highlighting and attachments imo. Cons are being tied to a
web site, anonymity, existence of moderators, etc. Seems a bit like
spreading the
On Mon, Jul 26, 2010 at 4:14 AM, S. Doaitse Swierstra doai...@swierstra.net
wrote:
I took a quick look at this file. To me it seems a mixture of a lexer and a
parser built on top of a home brewn parser library. I see function like
maybeWork which
(if I interpret correctly) test whether
There are two types of datatype contexts; haskell'98 contexts (which I
think are terrible), and GHC existential contexts (which I like):
class C a where runC :: a - Int
data C a = T1 a = D1 a
All this does is add a context to the D1 *constructor*; that is:
-- D1 :: C a = a - T1 a
But extracting
Hello all,
I created a little library that provides first-class event sources and
event stream transformers, both allowing side effects. For the time
being, the code is only available on GitHub [1]. The library is called
Moio, short for 'multiple-occurrence I/O', since event sources are
Oh, now I see! I knew about (and have used) existential contexts, but
somehow I hadn't made the connection that in a sense they are already
equivalent to our intuition for Haskell 98 contexts done right. :-)
Thanks!
Any chance of seeing them in Haskell'11?
Cheers,
Greg
On 07/26/10 10:44,
Hi,
thanks for the answer. This is my first attempt at Typeclasses, and I
think there is something deep that I don't understand...
On 26/07/10 15:03, Daniel Fischer wrote:
class JSON a where
toJValue :: a - JValue
fromJValue :: JValue - Either JSONError a
instance JSON JValue
2010/7/26 Ryan Ingram ryani.s...@gmail.com:
There are two types of datatype contexts; haskell'98 contexts (which I
think are terrible), and GHC existential contexts (which I like):
See also GADT-style data type declarations [1] and full GADT's [2],
which both behave like GHC existential
Hi all,
The darcs team would like to announce the immediate availability of darcs 2.5
beta 2 (also known as darcs 2.4.98.2 due to Cabal restrictions). Important
changes since darcs 2.4.4 are:
* trackdown can now do binary search with the --bisect option
* darcs always stores patch
Hi. I personally find web-forum a more convenient and structured way
of communication. I will help if the forum exports posts or topics as a
feed.
Are you strictly devoted to phpBB? I think that fluxBB is a decent
choice. Just suggesting.
On 26.07.10 16:30, Daniel Díaz wrote:
I want to
On Jul 26, 6:45 pm, Nick Bowler nbow...@elliptictech.com wrote:
Since when do mailing lists not have threading? Web forums with proper
support for threading seem to be few and far apart.
Most of the email clients I'm familiar with don't support threaded
displays and most of the web forums I'm
Vo Minh Thu wrote:
The idea of a forum has been brought to this list a few times in the
past. Unfortunately for those who thought it was a good idea, it
didn't really catched up.
Haskellers are generaly found of the mailing-list interface.
I'm not particularly fond of mailing lists. It's a
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On 7/26/10 15:56 , Andrew Coppin wrote:
My personal preference would be for NNTP. It seems to handle threading much
better. You can easily kill threads you're not interested in, and
thereafter not bother downloading them. You can use several
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On 7/26/10 15:54 , Kevin Jardine wrote:
On Jul 26, 6:45 pm, Nick Bowler nbow...@elliptictech.com wrote:
Since when do mailing lists not have threading? Web forums with proper
support for threading seem to be few and far apart.
Most of the
On 20:56 Mon 26 Jul , Andrew Coppin wrote:
My personal preference would be for NNTP. It seems to handle threading
much better. You can easily kill threads you're not interested in, and
thereafter not bother downloading them. You can use several different
client programs. And so on.
On Jul 26, 10:10 pm, Evan Laforge qdun...@gmail.com wrote:
Interesting, I've never figured out why some people prefer forums, but
you're proof that they exist :)
This debate is eerily similar to several others I've seen (for
example, on the interactive fiction mailing list).
In every case
On 13:28 Mon 26 Jul , Kevin Jardine wrote:
On Jul 26, 10:10 pm, Evan Laforge qdun...@gmail.com wrote:
Interesting, I've never figured out why some people prefer forums, but
you're proof that they exist :)
This debate is eerily similar to several others I've seen (for
example, on
On 26.07.2010 08:33, David Virebayre wrote:
listeEtagTot = concatMap (`listeEtagArm` cfgTypesTringle) listeArmOrd
You can use flip as a wildcard aswell:
listeEtagTot = concatMap (listeEtagArm `flip` cfgTypesTringle)
listeArmOrd
Makes it even more readable in my opinion, since this really
Wow, great paper! I got somewhat scared when I saw the first
description of the scene, but after I started reading I couldn't stop
anymore =D.
Thanks,
--
Felipe.
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On Monday 26 July 2010 21:03:10, Angel de Vicente wrote:
Hi,
thanks for the answer. This is my first attempt at Typeclasses, and I
think there is something deep that I don't understand...
On 26/07/10 15:03, Daniel Fischer wrote:
class JSON a where
toJValue :: a - JValue
On Jul 26, 10:37 pm, Nick Bowler nbow...@elliptictech.com wrote:
It seems to me, then, that a wine-like web forum - mailing list
gateway would satisfy everyone without fragmenting the community?
Seehttp://forum.winehq.org/viewforum.php?f=2.
--
Nick Bowler, Elliptic Technologies
On Jul 26, 10:37 pm, Nick Bowler nbow...@elliptictech.com wrote:
It seems to me, then, that a wine-like web forum - mailing list
gateway would satisfy everyone without fragmenting the community?
Definitely looks like an interesting option, although since Google
groups and any decent web forum
That's just cool. I now reverse my original statement - 'flip' does have
it's place in the pantheon of standard Haskell functions.
-deech
On Mon, Jul 26, 2010 at 3:42 PM, Nils m...@n-sch.de wrote:
On 26.07.2010 08:33, David Virebayre wrote:
listeEtagTot = concatMap (`listeEtagArm`
Not distributed (yet) but concurrent:
http://hackage.haskell.org/package/actor
The paper Actors with Multi-headed Message Receive Patterns. COORDINATION
2008http://www.informatik.uni-trier.de/%7Eley/db/conf/coordination/coordination2008.html#SulzmannLW08:
describes the design rationale.
Cheers,
On Mon, Jul 26, 2010 at 04:37:45PM -0400, Nick Bowler wrote:
On 13:28 Mon 26 Jul , Kevin Jardine wrote:
On Jul 26, 10:10 pm, Evan Laforge qdun...@gmail.com wrote:
Interesting, I've never figured out why some people prefer forums, but
you're proof that they exist :)
This
Brandon S Allbery KF8NH wrote:
On 7/26/10 15:56 , Andrew Coppin wrote:
My personal preference would be for NNTP. It seems to handle threading much
better. You can easily kill threads you're not interested in, and
thereafter not bother downloading them. You can use several different client
On Monday 26 July 2010 22:10:46, Evan Laforge wrote:
Apart from threading and attachments, are there other
reasons you prefer a forum?
I'm a mailing list guy too, but one possible advantage of a forum is that
it might be easier to search by topic.
Have a problem with type families?
Go to the
On 13:58 Mon 26 Jul , John Meacham wrote:
There already is an NNTP - mailing list gateway via gmane that gives a
nice forumy and threaded web interface for those with insufficient email
readers. Adding a completely different interface seems unnecessary and
fragmentary.
On Jul 26, 2010, at 6:59 PM, Andy Stewart wrote:
cabal install gtk
fails with the message
Configuring gtk-0.11.0...
setup: ./Graphics/UI/Gtk/General/IconTheme.chs: invalid argument
cabal: Error: some packages failed to install:
gtk-0.11.0 failed during the building phase. The
I have recently installed the Haskell Platform (for the first time) to a MS
Windows network drive; e.g.:
H:\aaa\bbb\Haskell Platform\2010.1.0.0\
I did so without admin privs.
It has ghc-6.12.1
I need to not install to C:.
I would like to install and use Gtk2Hs and Glade on the Platform also.
On 26/07/10 22:01, Andrew Coppin wrote:
Brandon S Allbery KF8NH wrote:
On 7/26/10 15:56 , Andrew Coppin wrote:
My personal preference would be for NNTP. It seems to handle
threading much
better. You can easily kill threads you're not interested in, and
thereafter not bother downloading
On Mon, Jul 26, 2010 at 10:42 PM, Nils m...@n-sch.de wrote:
On 26.07.2010 08:33, David Virebayre wrote:
listeEtagTot = concatMap (`listeEtagArm` cfgTypesTringle) listeArmOrd
You can use flip as a wildcard aswell:
listeEtagTot = concatMap (listeEtagArm `flip` cfgTypesTringle) listeArmOrd
Hi,
And now that we are at it... In the next page, 152 there is the
following instance definition, but no explanation is (I think) given of
what it means:
instance (JSON a) = JSON [a] where
until then all instance definitions where of the type
instance JSON Int where ...
How should I read
On Monday 26 July 2010 23:25:27, Max Rabkin wrote:
It took me a fair while (I'm talking on the order of half a minute) to
figure out what that meant, but it's pretty cool.
Yeah, really neat.
Maybe a different
name would be better? How about (??) or it?
listeEtagTot = concatMap
2010/7/26 Daniel Fischer daniel.is.fisc...@web.de:
On Monday 26 July 2010 23:25:27, Max Rabkin wrote:
It took me a fair while (I'm talking on the order of half a minute) to
figure out what that meant, but it's pretty cool.
Yeah, really neat.
Maybe a different
name would be better? How
2010/7/26 Vo Minh Thu not...@gmail.com:
2010/7/26 Daniel Fischer daniel.is.fisc...@web.de:
On Monday 26 July 2010 23:25:27, Max Rabkin wrote:
It took me a fair while (I'm talking on the order of half a minute) to
figure out what that meant, but it's pretty cool.
Yeah, really neat.
Maybe a
On Mon, Jul 26, 2010 at 2:06 PM, Peter Schmitz ps.hask...@gmail.com wrote:
I have recently installed the Haskell Platform (for the first time) to a MS
Windows network drive; e.g.:
H:\aaa\bbb\Haskell Platform\2010.1.0.0\
I did so without admin privs.
It has ghc-6.12.1
I need to not
It seems confusing to alias a function without adding any functionality just
to make things slightly easier to read. Instead wouldn't it be better if
this idiom were documented on haskell.org?
-deech
On Mon, Jul 26, 2010 at 4:47 PM, Vo Minh Thu not...@gmail.com wrote:
2010/7/26 Vo Minh Thu
I think it is pretty cool as well. But I think there is a problem with
viewing it as a wildcard.
let's say we define the following:
(??) = flip
foo :: a - b - c
foo ?? x :: a - c
Perfect!
But saying ?? can be used as a wildcard might in the following wrong
perception:
foo x ?? :: b - c --
Is there a specific reason why Set doesn't have instances for Functor
and Traversable? Or have they just not been written yet? :-)
Cheers,
Greg
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Hi all,
I'm spidering web pages, the implementation currently is synchronous.
I'd like to parallelize this for speed-up, ie. get up to 6 pages in
parallel and recycle those threads.
Now I have come across good examples for this on the web before, but I
doubt I'd find it again right away.
On Mon, 26 Jul 2010, Gregory Crosswhite wrote:
Is there a specific reason why Set doesn't have instances for Functor
and Traversable?
Sure, fmap needs an Ord restriction for the element type, which is not
possible for the plain Functor constructor class. E.g. in
fmap (const 'a') set
IMO, if you really want a wildcard, just write a lambda...
\x - foo 1 x 3
Cheers,
Edward
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2010/7/26 Günther Schmidt gue.schm...@web.de:
Hi all,
Hello!
I'm spidering web pages, the implementation currently is synchronous. I'd
like to parallelize this for speed-up, ie. get up to 6 pages in parallel and
recycle those threads.
This is usually called concurrent programming, not
On Jul 27, 2010, at 1:16 AM, Angel de Vicente wrote:
data JValue = JString String
| JNumber Double
| JBool Bool
| JNull
| JObject [(String, JValue)]
| JArray [JValue]
deriving (Eq, Ord, Show)
type JSONError = String
2010/7/26 Felipe Lessa felipe.le...@gmail.com:
downloader :: TChan (Maybe Page) - TChan (Page, Info) - IO ()
downloader in out = do
mp - atomically (readTChan in)
case mp of
Nothing - return ()
Just p - download p = atomically . writeTChan out
Oops! Of course there should be
Dear Felipe,
thank you for the code and for the correction :).
As usual I come across interesting stuff when I have no immediate need
for it and when I do I can't find it anymore.
I am looking for something slightly more abstracted and iirc there
recently was a post about the pi-calculus
Hi Sebastian,
I enjoyed this paper very much. Writing papers in the style of a play seems to
work very well! (although I think you should spice it up more if your want to
get it on Broadway)
It seems that only shift needs the reg field of the RegW datatype. So you can
also replace the reg
On 26.07.2010 23:55, Ozgur Akgun wrote:
I think it is pretty cool as well. But I think there is a problem with
viewing it as a wildcard.
let's say we define the following:
(??) = flip
foo :: a - b - c
foo ?? x :: a - c
Perfect!
But saying ?? can be used as a wildcard might in the following
On Jul 27, 2010, at 3:02 AM, Brandon S Allbery KF8NH wrote:
As I understand it:
1) carrying [contexts] around complicates Haskell98 (and now Haskell2010)
compatibility (also see below);
Like the availability of so many other features,
this one could be controlled by a language pragma.
2)
On Jul 27, 2010, at 8:12 AM, Nick Bowler wrote:
On 20:56 Mon 26 Jul , Andrew Coppin wrote:
My personal preference would be for NNTP. It seems to handle threading
much better. You can easily kill threads you're not interested in, and
thereafter not bother downloading them. You can use
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