2010/2/2 Álvaro García Pérez agar...@babel.ls.fi.upm.es
You may try Pierce's Basic Category Theory for Computer Scientists or
Awodey's Category Theory, whose style is rather introductory. Both of them
(I think) have a chapter about functors where they explain the Hom functor
and related
2009/10/7 Robert Atkey bob.at...@ed.ac.uk:
What is a DSL?
How about this as a formal-ish definition, for at least a pretty big
class of DSLs:
A DSL is an algebraic theory in the sense of universal algebra. I.e. it
is an API of a specific form, which consists of:
a) a collection of
On Fri, Apr 3, 2009 at 11:49 AM, Michael Roth mr...@nessie.de wrote:
Hello list,
maybe I'm just stupid, I'm trying to do something like this:
import Control.Monad
import Control.Monad.Trans
import Control.Monad.List
foobar = do
a - [1,2,3]
2009/3/24 John Van Enk vane...@gmail.com:
Is this the part where all the pundits come out and talk about how Jeff
isn't a citizen, eats babies, and wants to turn Haskell into an imperative
language?
Well given the fact that Haskell has been called the world's best
imperative language, that we
2009/3/11 Peter Verswyvelen bugf...@gmail.com:
When I put
{-# OPTIONS_GHC -Wall -Werror #-}
in my source file, I don't get compiler (GHC) warnings about redundant
language extensions that I enabled.
It would be nice if the compiler gave warnings about this, since after
refactoring, some
Hello,
I'd like to announce the release of the happstack-0.2 compatible
release of happs-tutorial on hackage and available for perusing on
tutorial.happstack.com.
A number of changes occurred in this release:
* General cleanup of code for readability
* Migration to the new
Hello,
I'd like to announce the release of the happstack-0.2 compatible
release of happs-tutorial on hackage and available for perusing on
tutorial.happstack.com.
A number of changes occurred in this release:
* General cleanup of code for readability
* Migration to the new
Hello Haskellers,
I'm pleased to announce version 4.2.0 of Crypto has been uploaded to
Hackage that I am taking over maintenance of the library from
Dominic Steinitz. As of this release it should be cabal install'able
on GHC 6.10.1. I'm also pleased to announce that the darcs repo will
be
On Mon, Feb 16, 2009 at 7:30 PM, Antoine Latter aslat...@gmail.com wrote:
On Mon, Feb 16, 2009 at 12:48 PM, Creighton Hogg wch...@gmail.com wrote:
Hello Haskellers,
I'm pleased to announce version 4.2.0 of Crypto has been uploaded to
Hackage that I am taking over maintenance of the library
Hello Haskellers,
I'm pleased to announce version 4.2.0 of Crypto has been uploaded to
Hackage that I am taking over maintenance of the library from
Dominic Steinitz. As of this release it should be cabal install'able
on GHC 6.10.1. I'm also pleased to announce that the darcs repo will
be
On Mon, Feb 16, 2009 at 7:30 PM, Antoine Latter aslat...@gmail.com wrote:
On Mon, Feb 16, 2009 at 12:48 PM, Creighton Hogg wch...@gmail.com wrote:
Hello Haskellers,
I'm pleased to announce version 4.2.0 of Crypto has been uploaded to
Hackage that I am taking over maintenance of the library
HAppS/Happstack more accessible. Please feel free to e-mail me with
any comments, errata, or threats of bodily harm.
Cheers,
Creighton Hogg
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HAppS/Happstack more accessible. Please feel free to e-mail me with
any comments, errata, or threats of bodily harm.
Cheers,
Creighton Hogg
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On Thu, Feb 5, 2009 at 6:58 PM, Don Stewart d...@galois.com wrote:
andrewcoppin:
Jochem Berndsen wrote:
The HAppS project has been abandoned, see
http://groups.google.com/group/HAppS/msg/d128331e213c1031 .
The Happstack project is intended to continue development. For more
details, see
2009/1/29 Conal Elliott co...@conal.net:
Hi Achim,
I came to the same conclusion: I want to sweep aside these OO, imperative
toolkits, and replace them with something genuinely functional, which for
me means having a precise simple compositional (denotational) semantics.
Something
On Mon, Feb 2, 2009 at 3:28 PM, Conal Elliott co...@conal.net wrote:
On Mon, Feb 2, 2009 at 11:39 AM, Creighton Hogg wch...@gmail.com wrote:
snip
I think working on a purely functional widget toolkit would actually
be a really cool project. Do you have any ideas, though, on what
should
On Tue, Jan 20, 2009 at 1:50 PM, Paul Johnson p...@cogito.org.uk wrote:
Tom Hawkins wrote:
Such a database would help me counter by boss's
argument that it's impossible to find and hire Haskell programmers.
There was a thread last week where someone asked who would be interested in
a
On Thu, Jan 15, 2009 at 10:46 AM, Ross Mellgren rmm-hask...@z.odi.ac wrote:
snip
Usually when encountering something like Monoid (if I didn't already know
it), I'd look it up in the library docs. The problem I've had with this
tactic is twofold:
First, the docs for the typeclass usually don't
On Thu, Jan 15, 2009 at 10:18 PM, Jonathan Cast
jonathancc...@fastmail.fm wrote:
On Thu, 2009-01-15 at 17:06 -0500, Steve Schafer wrote:
On Thu, 15 Jan 2009 13:21:57 -0800, you wrote:
Where, in the history of western civilization, has there ever been an
engineering discipline whose adherents
2009/1/9 John A. De Goes j...@n-brain.net:
If you're looking for a project to take on, I would suggest starting with
the following:
A high-level, type-safe AMQP client written in 100% Haskell, which provides
a clean way of handling hundreds of unique message types.
Then it would be
On Thu, Jan 8, 2009 at 8:32 AM, John A. De Goes j...@n-brain.net wrote:
Haskell's networking support is very rudimentary. Erlang's is quite
sophisticated. For network intensive applications, especially those
requiring messaging, fault-tolerance, distribution, and so forth, there's no
doubt
On Thu, Jan 8, 2009 at 12:06 PM, Don Stewart d...@galois.com wrote:
wchogg:
On Thu, Jan 8, 2009 at 8:32 AM, John A. De Goes j...@n-brain.net wrote:
Haskell's networking support is very rudimentary. Erlang's is quite
sophisticated. For network intensive applications, especially those
On Thu, Jan 8, 2009 at 2:02 PM, John A. De Goes j...@n-brain.net wrote:
On Jan 8, 2009, at 12:56 PM, Tim Newsham wrote:
You replied to someone discussing using Haskell at a CDN to implement
things like web servers by saying that Haskell wasn't suitable for
the task.
That is incorrect. I
Hello Haskellers,
For those of your who aren't nose-deep in Real World Haskell at the
moment, I'd like to start a small group for the O'Reilly book
Programming Collective Intelligence*. I think it might be very
instructive to convert the examples exercises to Haskell. I think
it would be good
On Fri, Dec 5, 2008 at 9:49 AM, Duncan Coutts
[EMAIL PROTECTED] wrote:
On Thu, 2008-12-04 at 13:06 -0600, Creighton Hogg wrote:
Hello,
Since hsc2hs is distributed with GHC, I thought this might be a decent
place to ask. I tried to run hsc2hs on a file that I know worked with
my 6.8.3
Hello,
Since hsc2hs is distributed with GHC, I thought this might be a decent
place to ask. I tried to run hsc2hs on a file that I know worked with
my 6.8.3 installation, but now I'm getting the error
/usr/local/lib/ghc-6.10.1/hsc2hs-0.67/template-hsc.h:4:19: error:
HsFFI.h: No such file or
.
Cheers,
Creighton
On Thu, Dec 4, 2008 at 1:06 PM, Creighton Hogg [EMAIL PROTECTED] wrote:
Hello,
Since hsc2hs is distributed with GHC, I thought this might be a decent
place to ask. I tried to run hsc2hs on a file that I know worked with
my 6.8.3 installation, but now I'm getting the error
Hello,
So I'm trying to debug an issue that is causing GHC to emit the
loop warning. I was hoping to get more information about what
exactly that tells me about the kind of problem, other than the
obvious interpretation that I appear to be getting into some kind of
infinite loop. What is GHC
Hello Haskellers,
So I have a bit of a follow up question after reading Theorems For
Free! this weekend.
There's a throw away comment near the beginning about how you can
recast the results into category theoretic form, but using lax natural
transformations.
Now I'm assuming this means a natural
On Thu, Oct 16, 2008 at 7:28 AM, Mauricio [EMAIL PROTECTED] wrote:
Hi,
Some functions in C changes data using pointers,
like this example:
void change_int (int *n)
{
*n ++;
}
What is the proper way to handle that? I
guess I should wrap it like this:
foreign ccall change_int
2008/10/16 Donnie Jones [EMAIL PROTECTED]:
Hello Svein Ove Aas,
On Thu, Oct 16, 2008 at 12:31 PM, Svein Ove Aas [EMAIL PROTECTED] wrote:
I'd finally gotten to the point in learning haskell at which they
might be interesting to look at, and then.. they were gone.
Does anyone know what
On Thu, Oct 16, 2008 at 3:47 PM, Kenny Graunke [EMAIL PROTECTED] wrote:
Hello!
On Thu, Oct 16, 2008, Donnie Jones donnie at darthik.com wrote:
[snip]
The site is working for me even now.
Unfortunately, the site hasn't really been updated much over the past
couple of years and when I
So in my quest to create bindings to BlueZ in Haskell, I've hit a bit
of a snag: sockets programming.
In C, you can use the standard sockets library and just pass around
addresses as arrays of 6 bytes instead of arrays of 4 bytes like you
normally would. The problem I'm having is that in
On Wed, Oct 15, 2008 at 12:26 PM, Bryan O'Sullivan [EMAIL PROTECTED] wrote:
On Wed, Oct 15, 2008 at 6:54 AM, Creighton Hogg [EMAIL PROTECTED] wrote:
Is there a way around this that I just haven't seen, or should I write
a patch to Network to add an extra constructor to SockAddr and code
On Mon, Oct 13, 2008 at 1:35 PM, Albert Y. C. Lai [EMAIL PROTECTED] wrote:
Alex Queiroz wrote:
On Fri, Oct 10, 2008 at 5:48 PM, Andrew Coppin
In what way? As far as I'm aware, .NET never really caught on and has
long
since become obsolete.
In what alternate universe?
Anthropic
Hey Haskell,
So for a fairly inane reason, I ended up taking a couple of minutes
and writing a program that would spit out, to the console, the number
of lines in a file. Off the top of my head, I came up with this which
worked fine with files that had 100k lines:
main = do
path - liftM head $
On Thu, Sep 18, 2008 at 1:29 PM, Don Stewart [EMAIL PROTECTED] wrote:
wchogg:
Hey Haskell,
So for a fairly inane reason, I ended up taking a couple of minutes
and writing a program that would spit out, to the console, the number
of lines in a file. Off the top of my head, I came up with this
On Thu, Sep 18, 2008 at 1:55 PM, Don Stewart [EMAIL PROTECTED] wrote:
wchogg:
On Thu, Sep 18, 2008 at 1:29 PM, Don Stewart [EMAIL PROTECTED] wrote:
snip
This makes me cry.
import System.Environment
import qualified Data.ByteString.Lazy.Char8 as B
main = do
[f] -
On Thu, Sep 18, 2008 at 1:55 PM, Don Stewart [EMAIL PROTECTED] wrote:
wchogg:
On Thu, Sep 18, 2008 at 1:29 PM, Don Stewart [EMAIL PROTECTED] wrote:
wchogg:
Hey Haskell,
So for a fairly inane reason, I ended up taking a couple of minutes
and writing a program that would spit out, to the
On Wed, May 21, 2008 at 6:37 PM, Neil Mitchell [EMAIL PROTECTED] wrote:
Hi
Real Haskell Programmers Only Use Top Level IO!
(But then again, real programmers wouldn't use Haskell:
http://www.pbm.com/~lindahl/real.programmers.htmlhttp://www.pbm.com/%7Elindahl/real.programmers.html
)
/rosetta.pdf
Creighton Hogg
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could I find a proof that the initial algebras final coalgebras of
CPO coincide? I saw this referenced in the Bananas.. paper as a fact, but
am not sure where this comes from.
Thanks,
Creighton Hogg
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point of some functor F, not the functor itself.
I'm sure I'm just being dumb, but this is really bugging me.
Thanks,
Creighton Hogg
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On 9/25/07, Philippa Cowderoy [EMAIL PROTECTED] wrote:
On Tue, 25 Sep 2007, Seth Gordon wrote:
Are Benjamin C. Pierce's _Types and Programming Languages_ and/or _Basic
Category Theory for Computer Scientists_ suitable for self-study?
Basic Category Theory depends on your mindset
Hi Haskell,
Sorry to contribute to the noise but given that we've been talking about
categories lately, I was wondering if anyone had any opinions on good
universities for studying category theory. I'm trying to figure out where
to apply for my phd. I want to either be at a place with a strong
On 7/9/07, Dan Piponi [EMAIL PROTECTED] wrote:
On 7/8/07, Thomas Conway [EMAIL PROTECTED] wrote:
The basic claim appears to be that discrete mathematics is a bad
foundation for computer science. I suspect the subscribers to this
list would beg to disagree.
Wearing my tin foil hat for the
On 7/9/07, Conor McBride [EMAIL PROTECTED] wrote:
Hi all
On 9 Jul 2007, at 06:42, Thomas Conway wrote:
I don't know if you saw the following linked off /.
http://www.itwire.com.au/content/view/13339/53/
[..]
The basic claim appears to be that discrete mathematics is a bad
foundation
On 7/10/07, Aaron Denney [EMAIL PROTECTED] wrote:
On 2007-07-10, Sebastian Sylvan [EMAIL PROTECTED] wrote:
On 10/07/07, Andrew Coppin [EMAIL PROTECTED] wrote:
Sebastian Sylvan wrote:
That might eliminate the concurrency imperative (for a while!), but
it
doesn't adress the productivity
On 7/10/07, Jim Burton [EMAIL PROTECTED] wrote:
Andrew Coppin wrote:
On the one hand, it feels exciting to be around a programming language
where there are deep theoretical discoveries and new design territories
to be explored. (Compared to Haskell, the whole C / C++ / Java /
JavaScript
A lot of people have had comments on this thread, but I have a off-hand
question: what data types are required by the 98 standard? I figured it
was just lists tuples because they have syntactic support, but is that
true?
Thanks,
Creighton
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On 6/18/07, Andrew Coppin [EMAIL PROTECTED] wrote:
Pasqualino 'Titto' Assini wrote:
I think that we should not underestimate the transforming power of
dogged
determination.
Think of Linux: only a terminal idiot could have conceived the plan of
writing
from scratch a clone of a 20 years old
On 6/18/07, Andrew Coppin [EMAIL PROTECTED] wrote:
Mark T.B. Carroll wrote:
Are KWrite and Kate something to do with KDE or something? One of the
first things I do with a new Linux install is to dump all the KDE and
Gnome stuff on the basis that it's an enormous amount of bloatware for
On 6/18/07, Andrew Coppin [EMAIL PROTECTED] wrote:
Creighton Hogg wrote:
On 6/18/07, *Andrew Coppin* [EMAIL PROTECTED]
mailto:[EMAIL PROTECTED] wrote:
That reminds me... Somebody should write an *OS* in Haskell! :-D
Well, there hasn't been a lot of work done on the subject but you
On 6/18/07, Andrew Coppin [EMAIL PROTECTED] wrote:
Creighton Hogg wrote:
Well, since we're on the subject and it's only the Cafe list, what is
it that you find messy about Linux that you would want to be solved by
some hypothetical Haskell OS?
This is drifting off-topic again, but here goes
On 6/18/07, Creighton Hogg [EMAIL PROTECTED] wrote:
On 6/18/07, Andrew Coppin [EMAIL PROTECTED] wrote:
Creighton Hogg wrote:
There are lots of things to like about Linux. It doesn't cost
money.
It's fast. It's reliable. It's flexible. It's secure.
Okay, I'm not sure
On 6/18/07, Thomas Conway [EMAIL PROTECTED] wrote:
On 6/19/07, Creighton Hogg [EMAIL PROTECTED] wrote:
Okay, I remember seeing an example of this before , but I'm not sure if
I
see what language based security Haskell's type system could provide in
protecting address spaces from each other
On 5/31/07, Brandon S. Allbery KF8NH [EMAIL PROTECTED] wrote:
On May 31, 2007, at 15:47 , Andrew Coppin wrote:
If you're bored... can you come up with a solution to this?
http://warp.povusers.org/ProgrammingChallenge.html
Is it me, or does this look like a job for Data.Binary?
It's not
On 5/26/07, Mark Engelberg [EMAIL PROTECTED] wrote:
I'd like to write a memoization utility. Ideally, it would look
something like this:
memoize :: (a-b) - (a-b)
memoize f gives you back a function that maintains a cache of
previously computed values, so that subsequent calls with the same
On 5/29/07, Andrew Coppin [EMAIL PROTECTED] wrote:
Claus Reinke wrote:
phantom types:
the types of ghost values (in other words, we are only interested in
the type, not in any value of that type).
Mmm... Still not seeing a great amount of use for this one.
Okay,
On 5/30/07, Isaac Dupree [EMAIL PROTECTED] wrote:
-BEGIN PGP SIGNED MESSAGE-
Hash: SHA1
Creighton Hogg wrote:
Now maybe I'm being dense here, but would you really *want* a way in
Haskell
to do something like
memo :: (a-b) - a-b
since it changes the semantics of the function
On 5/30/07, Jon Harrop [EMAIL PROTECTED] wrote:
I've found HOpenGL and the Debian package libghc6-opengl-dev. The former
seems
to be very out of date (last release 2003) but I can't find any demos for
the
latter.
Where should I go to get started with OpenGL and Haskell?
For at least GHC
On 5/23/07, Tom Harper [EMAIL PROTECTED] wrote:
I really hope they choose the flying squirrel.
They should just use that picture of Philip Wadler as Lambda-Man.
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Hi
On 5/14/07, Veer Singh [EMAIL PROTECTED] wrote:
Hello,
I am trying to learn haskell , but i am struggling with types , its
been around 7 days , it will be very kind if some explain it why this
error , i think this is the only stumbling block . I am looking for
the comparison on why similar
On 5/10/07, Dan Weston [EMAIL PROTECTED] wrote:
I've been pronouncing monad like gonad (moh-nad), but it occurs to me
that it might be pronounced like monoid (mah-nad).
Is there an official way to pronouce this word - maybe with a Scottish
accent? :)
I've always said mah-nad, mah-noyd, and
Hi,
I've been reading it off and on for a couple of months. I definitely
wouldn't say it'll make you a better programmer, but it's a pretty nice,
gentle, introduction to some basic category theory and some uses of topoi.
Read it if you're interested in all that, not if you're just focused on
On 3/27/07, [EMAIL PROTECTED] [EMAIL PROTECTED] wrote:
Given the amount of material posted at haskell.org and elsewhere
explaining IO, monads and functors, has anyone considered publishing
a comprehensive book explaining those subjects? (I am trying to
read all the material online, but books
On 3/27/07, Dan Piponi [EMAIL PROTECTED] wrote:
On 3/27/07, [EMAIL PROTECTED] [EMAIL PROTECTED] wrote:
Given the amount of material posted at haskell.org and elsewhere
explaining IO, monads and functors, has anyone considered publishing
a comprehensive book explaining those subjects? (I am
On 3/20/07, Dan Weston [EMAIL PROTECTED] wrote:
Dan Weston wrote:
Douglas Philips wrote:
On 2007 Mar 20, at 3:30 PM, Dan Weston indited:
I looked up John Backus on wikipedia and followed a link to ALGOL:
http://en.wikipedia.org/wiki/ALGOL_60
where the following undesirable property of
On 2/13/07, Duncan Coutts [EMAIL PROTECTED] wrote:
On Tue, 2007-02-13 at 15:27 -0500, Jefferson Heard wrote:
Hi, I am running the following code against a 210 MB file in an attempt
to
determine whether I should use alex or whether, since my needs are very
performance oriented, I should write
On 2/13/07, Bernie Pope [EMAIL PROTECTED] wrote:
Creighton Hogg wrote:
This may be silly of me, but I feel like this is an important point:
so you're saying that tail recursion, without strictness, doesn't run
in constant space?
It is an important point, and a classic space bug (see foldl
On 2/12/07, [EMAIL PROTECTED] [EMAIL PROTECTED] wrote:
Hello,
the Advanced Monads page in the Haskell Wikibook
(http://en.wikibooks.org/wiki/Haskell/Advanced_monads) contains the
following
example of a List Monad
pythags = do
x - [1..]
y - [x..]
z - [y..]
guard
On 2/10/07, Matthew Brecknell [EMAIL PROTECTED] wrote:
Rafael Almeida said:
I've always found the following definition of the sieve of eratosthenes
the clearest definition one could write:
sieve [] = []
sieve (x:xs) = x : sieve [y | y - xs, y `mod` x /= 0]
It doesn't perform better than
to learn a bit more
about how to optimize Haskell code.
Cheers,
Creighton Hogg
-- Naive way to calculate prime numbers, testing each new n to see if it has
prime factors less than sqrt(n).
import Data.List
primes = 2:(foldr (\x y - if isPrime x then x:y else y) [] [3..])
where isPrime x = foldl' (\z
there. I should have proofread.
Also, your code is not idiomatic Haskell.
Here's a different version:
primes :: [Int]
primes = 2:filter isPrime [3,5..]
where isPrime x = all (\ y - x `mod` y /= 0) $ takeWhile (\ p -
p*p = x) primes
On Feb 10, 2007, at 21:02 , Creighton Hogg wrote
On 2/10/07, Creighton Hogg [EMAIL PROTECTED] wrote:
On 2/10/07, Lennart Augustsson [EMAIL PROTECTED] wrote:
There are many things that makes your code slow.
* The default for Haskell is to compute with Integer, not Int. So
that makes from Integral and floor very slow.
* foldl' is a bad
On 2/10/07, Peter Berry [EMAIL PROTECTED] wrote:
Gah! Gmail has really broken defaults for posting to lists.
On 10/02/07, Creighton Hogg [EMAIL PROTECTED] wrote:
Hello Haskell-ers,
So a friend and I were thinking about making code faster in Haskell, and
I
was wondering if there was a way
On 2/10/07, [EMAIL PROTECTED] [EMAIL PROTECTED] wrote:
Creighton Hogg wrote:
Hello Haskell-ers,
So a friend and I were thinking about making code faster in Haskell, and
I
was wondering if there was a way to improve the following method of
generating the list of all prime numbers. It takes
Hi Haskell-ers,
So I think I understand the idea of creating a heterogenous list using
typeclasses and existentials, but I don't see how to filter the list
to retrieve elements of the list that are of only one type.
More concretely, taking the example
Good afternoon Haskellers,So I'm trying to understand how STM works, and wrote a quick 'eating philosophers' example to see if I understood how it's supposed to work.The problem is that while it executes, it doesn't appear to *do* anything.
Did I completely write things wrongheadedly or am I being
Hello Haskell'rs,
I've been playing with threads and I tried to do a toy example (that used java) from a class.
When run, the program should print a prompt and accept commands just like a linux shell. It doesn't have to do anything
fancy, just spawn new threads that make system calls when
with GHC's innards, is there anything particular I should begin with? At the moment I'm just reading through the user's guide.
Cheers,Creighton Hogg
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that *could* build ghc correctly.
Thanks,Creighton Hogg
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in the language without sacrificing too much
performance and having a hundred times the flexibility and
*maintainability*.
Creighton Hogg
On 4/22/06, Paolo Martini [EMAIL PROTECTED] wrote:
Hello everybody, nice to meet you all.
Last year I did work on an Haskell project during the first year of
the Google
On 13 Apr 2006 03:27:03 -, [EMAIL PROTECTED] [EMAIL PROTECTED] wrote:
Creighton Hogg wrote:
No instance for (MatrixProduct a (Vec b) c)
arising from use of `*' at interactive:1:3-5
Probable fix: add an instance declaration for (MatrixProduct a
(Vec b) c
Hi,
So I'm trying the fun-deps example from
http://www.haskell.org/hawiki/FunDeps and seeing if I can
use it, but I can't really get things to work the way I want.
The code follows below, and the error I get if I try to multiply
10 * (vector 10 [0..9]) is
No instance for (MatrixProduct a (Vec
Hi,
If I have something like
data Patootie = Pa Int | Tootie Int
and I want to pull out the indices of all elements of a list
that have type constructor Tootie, how would I do that?
I thought I might be able to use findIndices, but I don't
know how to express the predicate.
On Thu, 2 Feb 2006, Henrik Nilsson wrote:
Hi all,
To corroborate Wadler's law further.
Josef wrote:
Oh yes, it does happen that a single line comment begins with a
special symbol. It has happened to me on several occations when using
haddock annotation to my source code. It is
Hi guys,
So one of the big things in object oriented programming is
encapsulation, and I'm wondering how to do it properly in
Haskell. How do you define new data types but minimize the
dependence of external packages on the exact nature of the
data definition?
On Wed, 21 Dec 2005, Robin Green wrote:
Henning Thielemann wrote:
Starting with IO in Haskell is like starting LaTeX with rotating text and
making it colorful.
Not at all!
Indeed IO _is_ complicated regardless of whether it is
modelled by Monads in Haskell or differently in other
On Wed, 21 Dec 2005, Daniel Carrera wrote:
Hi all,
I'm a Haskell newbie and I don't really understand how Haskell deals
with functions that really must have side-effects. Like a rand()
function or getLine().
I know this has something to do with monads, but I don't really
understand
On Wed, 21 Dec 2005, Henning Thielemann wrote:
On Wed, 21 Dec 2005, Creighton Hogg wrote:
I agree with this wholeheartedly. When I first started
playing with Haskell, some of the tutorials made it look
like it was very difficult to do anything practical with it
because doing real
On Wed, 21 Dec 2005, Daniel Carrera wrote:
Thanks for all the help. I think things are much clearer now. And this bit:
main = do putStrLn Hello, what is your name?
name - getLine
putStrLn (Hello, ++ name ++ !)
Looks quite straight forward.
I just wrote my very
On Wed, 21 Dec 2005, Daniel Carrera wrote:
Creighton Hogg wrote:
x is a String, getLine has type IO String. That's what I
was getting at in one of my last e-mails.
Hmm... let's see if I understand:
* getLine() has type IO String.
* The - will convert an IO String to a plain String
On Wed, 21 Dec 2005, Scherrer, Chad wrote:
From: Daniel Carrera [EMAIL PROTECTED]
Hey,
The sqrt function is not doing what I want. This is what I want:
round sqrt(2)
---
Daniel,
A lot of Haskell folks like to avoid
Hi guys,
I was wondering where I should get started in learing about
how to implement a haskell compiler?
Are there papers, wiki entries, or other things people think
would be helpful or should I just start looking at the
source of one of the compilers?
On Tue, 20 Dec 2005, John Meacham wrote:
On Tue, Dec 20, 2005 at 10:36:36AM -0600, Creighton Hogg wrote:
I was wondering where I should get started in learing about
how to implement a haskell compiler?
Snip Absolute Awesomeness
Wow! That was a great response, with more references than
Hi,
Has anyone recently tried to install the graphics libraries
included on
http://haskell.org/soe/software.htm ?
I've tried to make the libraries, but I get these errors.
make: Entering directory
`/home/wchogg/coding/haskell/GraphicsLib/lib/x11'
ffihugs +G +LX_stub_ffi.c X.hs
Warning:
On Fri, 11 Nov 2005, Gour wrote:
Wolfgang Jeltsch ([EMAIL PROTECTED]) wrote:
The advantage of newsgroups over mailing lists is that newsgroups are
designed
for discussions among several people and therefore newsgroup software
supports this kind of usage very well while mailing lists
Hi,
so I'm a newbie getting used to Haskell. I'm writing some
simple things like genetic algorithms in it for practice,
and I keep coming across something that really bugs me:
are there any standard libraries that allow you to
do imperative style for or while loops using monads to keep
On Thu, 27 Oct 2005, Creighton Hogg wrote:
On Thu, 27 Oct 2005, Robert Dockins wrote:
On Oct 27, 2005, at 11:54 AM, Creighton Hogg wrote:
Hi,
so I'm a newbie getting used to Haskell. I'm writing some
simple things like genetic algorithms in it for practice,
and I keep
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