On Mon, 5 Nov 2007, Andrew Coppin wrote:
randList :: Int - IO [Int]
randList n = mapM (\x - randomRIO (0, randMax)) [1..n]
replicateM n (randomRIO (0, randMax))
but it is certainly better to use randomR and wrap it in a State monad
___
On Mon, 5 Nov 2007, C.M.Brown wrote:
I was given a quandary this evening, suppose I have the following code:
Did you already try Prelude's 'asTypeOf' function?
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On Tue, 6 Nov 2007, marnes wrote:
fib :: Integer - Integer
fib n = fibaux n 0 1 1
where
fibaux :: Integer - Integer - Integer - Integer - Integer
fibaux i a b c | i==0 = a
| i/=0 = fibaux (i-1) b c (b+c)
http://www.haskell.org/haskellwiki/Memoization
On Tue, 6 Nov 2007 [EMAIL PROTECTED] wrote:
However, this is still an O(log n) algorithm, because that's the
complexity of raising-to-the-power-of. And it's slower than the
simpler integer-only algorithms.
You mean computing the matrix power of
/1 1\
\0 1/
?
On Thu, 8 Nov 2007, Stuart Cook wrote:
On 11/8/07, Tim Newsham [EMAIL PROTECTED] wrote:
Data.Maybe has functions for processing Maybe's but nothing useful
for creating maybe. I think the following would be a very useful
addition, a guarded function:
guarded :: (a - Bool) - (a -
On Thu, 8 Nov 2007 [EMAIL PROTECTED] wrote:
Report from the Rabbit Warren.
Thank you, everybody, for your contribution. The problem was, how to
construct a one-liner which generates the infinite Rabbit Sequence:
10110101101101011010110110101101101011010110110101101011011010110...
This is
On Wed, 7 Nov 2007, Tim Newsham wrote:
Data.Maybe has functions for processing Maybe's but nothing useful
for creating maybe. I think the following would be a very useful
addition, a guarded function:
guarded :: (a - Bool) - (a - b) - a - Maybe b
guarded p f x | p x = Just
On Fri, 9 Nov 2007, Derek Elkins wrote:
Pointless frobbing but is there any issue with setting the echo to False
when it is already False? Otherwise not checking seems to both simpler
and quicker (not that performance matters), i.e.
getpasswd h = do
wasEnabled - hGetEcho h
On Sat, 10 Nov 2007, Daniel Fischer wrote:
Since you seem to know a lot about these things, out of curiosity, do you know
how these functions are actually implemented? Do they use Taylor series or
other techniques?
I think that for sin and cos the Taylor series are a good choice. For
other
On Sat, 10 Nov 2007 [EMAIL PROTECTED] wrote:
Quoting [EMAIL PROTECTED]:
Then, a *rational* approximation gives you the same precision with
less coeffs. Nowadays the division is not sooo much more expensive
than the multiplication, so the efficiency doesn't suffer much.
It might not
On Sun, 11 Nov 2007, Andrew Coppin wrote:
Somebody just asked me
...if GHC is written in Haskell, how the heck did they compile GHC in
the first place?
... and what happens, if they add a new feature, use it in the compiler
itself, and then it turns out, that the implementation of the new
On Sun, 11 Nov 2007 [EMAIL PROTECTED] wrote:
G'day all.
Quoting [EMAIL PROTECTED]:
But... tell me please, ANYONE, who takes part in this inspiring
exchange: How many COBOL programs have you written in your life?
As you well know, only one COBOL program has ever been written. The
rest
On Mon, 12 Nov 2007, Chris Smith wrote:
Dan Piponi wrote:
Several months late I now have a simple test case for what I think is
either a GHC bug or a misexpectation on my part.
Here's what it looks like to me.
If there is a .hi and .o file sitting around for a module, then GHCi
will
On Mon, 12 Nov 2007, Derek Elkins wrote:
On Mon, 2007-11-12 at 15:51 -0800, Donn Cave wrote:
On Nov 12, 2007, at 12:00 PM, Galchin Vasili wrote:
I am looking for (objective.. i.e. not juts FPL cheerleading)
opinions as to why Wall Street ( http://www.janestcapital.com/) and
banking
On Tue, 13 Nov 2007, Jon Harrop wrote:
Penetration is highest in parts of industry where small groups of talented
programmers get together, most notably startups. Look at XenSource,
Wolfram Research, The MathWorks,
?? Mathematica and MatLab are just the opposite of statically safe
On Tue, 13 Nov 2007 [EMAIL PROTECTED] wrote:
Henning Thielemann writes:
?? Mathematica and MatLab are just the opposite of statically safe
programming.
Is this a religious statement, quite popular in our Church of Functionalism,
or you mean something concrete by that, and if yes
On Tue, 13 Nov 2007, Jon Harrop wrote:
On Tuesday 13 November 2007 08:41, Henning Thielemann wrote:
On Tue, 13 Nov 2007, Jon Harrop wrote:
Penetration is highest in parts of industry where small groups of
talented programmers get together, most notably startups. Look at
XenSource
On Tue, 13 Nov 2007 [EMAIL PROTECTED] wrote:
Henning Thielemann writes:
[EMAIL PROTECTED] wrote:
Henning Thielemann writes:
?? Mathematica and MatLab are just the opposite of statically safe
programming.
Is this a religious statement, quite popular in our Church
On Tue, 13 Nov 2007, Simon Peyton-Jones wrote:
Meanwhile, though, the best we can do is improve the documentation:
Dan, can you suggest any words we could add to the
documentation that would have prevented you stumbling?
... or even better - words that GHCi can say, when it
On Tue, 13 Nov 2007, John Lato wrote:
Hello,
I know there are several important differences between let-expressions
and where-clauses regarding scoping and the restriction of where to
a top-level definition. However, frequently I write code in which
either one would be allowed, and I was
On Tue, 13 Nov 2007, John Lato wrote:
I'd like to thank Henning for pointing out the wiki page, which
describes one consequence I hadn't considered. I knew I couldn't have
been the first person to have this question, but I somehow missed it
before. I agree with Neil, though, that it
On Tue, 13 Nov 2007, Dougal Stanton wrote:
-- int a = 3;
-- int *pa = a;
ampersand :: t - Pointer t
ampersand a = Just a
What's bad about using 'ampersand' function as replacement for the
constructor 'Just'?
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On Tue, 13 Nov 2007, Dougal Stanton wrote:
On 13/11/2007, Henning Thielemann [EMAIL PROTECTED] wrote:
On Tue, 13 Nov 2007, Dougal Stanton wrote:
-- int a = 3;
-- int *pa = a;
ampersand :: t - Pointer t
ampersand a = Just a
What's bad about using 'ampersand' function
On Wed, 14 Nov 2007, Jules Bean wrote:
Henning Thielemann wrote:
No problem, write a function like 'maybe' to inspect the data.
Instead of 'f m' with
f :: Maybe T - S
f (Just x) = g x
f Nothing = h
Yes. It is a problem.
Do you write all your code using higher-order functions
On Wed, 14 Nov 2007, Kurt Hutchinson wrote:
As part of a solution I'm working on for Project Euler problem 119, I
wanted to create an ordered list of all powers of all positive
integers (starting with squares). This is what I came up with:
powers = ( uniq . map fst . iterate next ) ( 1, (
On Tue, 13 Nov 2007, Dan Piponi wrote:
On Nov 13, 2007 1:24 PM, Ryan Ingram [EMAIL PROTECTED] wrote:
I tend to prefer where, but I think that guards function declarations are
more readable than giant if-thens and case constructs.
Up until yesterday I had presumed that guards only applied
On Thu, 15 Nov 2007, Jules Bean wrote:
Anecdotes have little value, but for what it's worth: in around 5 years
of ghc use, I have never, not even once, wanted to load the module I was
working on in its compiled form. I've occasionally noticed that
dependent modules get loaded quickly from
On Thu, 15 Nov 2007, Bulat Ziganshin wrote:
Hello Henning,
Thursday, November 15, 2007, 2:31:07 PM, you wrote:
Btw. I would write here
min 1 (max (-1) x)
or even better define a function for such clipping, since it is needed
quite often.
min 1 . max (-1) is pretty standard,
On Fri, 16 Nov 2007, jeff p wrote:
A function is an expression whose type is an arrow; e.g. Int - Int.
The type of taxRate is (Fractional t) = t.
I had this misunderstanding too, when starting with Haskell. In other
languages there are functions with zero, one or more arguments. In
contrast
On Thu, 15 Nov 2007, Duncan Coutts wrote:
On Thu, 2007-11-15 at 15:56 -0200, Maurício wrote:
Hi,
Is there a Haskellforge somewhere, i.e.,
something like a sourceforge for open source
Haskell programs, with darcs, automatic
cabalization etc.? Has anyone tried that
already?
There
On Tue, 30 Oct 2007, David Roundy wrote:
On Tue, Oct 30, 2007 at 05:24:21PM +0100, Henning Thielemann wrote:
When following the description on
http://www.haskell.org/haskellwiki/How_to_write_a_Haskell_program#Add_some_automated_testing:_QuickCheck
then darcs will run the QuickCheck
On Sun, 18 Nov 2007, Andrew Coppin wrote:
Lauri Alanko wrote:
Please note that if you're using GHC, bang patterns are often much
more convenient than $! or seq when you want to enforce strictness:
http://www.haskell.org/ghc/docs/latest/html/users_guide/bang-patterns.html
Wait, so...
On Mon, 19 Nov 2007, brad clawsie wrote:
i would categorize myself as a purely practical programmer. i enjoy
using haskell for various practical tasks and it has served me
reliably. one issue i have with the library support for practical
problem domains is the half-finished state of many
On Mon, 19 Nov 2007, Brandon S. Allbery KF8NH wrote:
On Nov 19, 2007, at 16:06 , Arthur van Leeuwen wrote:
here is a puzzle for you: try converting a
System.Posix.Types.EpochTime into either a
System.Time.CalendarTime or a Data.Time.Clock.UTCTime without going
through
read . show or
On Mon, 19 Nov 2007, Andrew Coppin wrote:
Arthur van Leeuwen wrote:
A closely related issue: fromIntegral is in Integral which also
requires quotRem. However,
the two are semantically quite disjoint. I can *easily* see the
semantics of fromIntegral
on EpochTime, but not the
On Mon, 19 Nov 2007, Brandon S. Allbery KF8NH wrote:
On Nov 19, 2007, at 15:47 , Radosław Grzanka wrote:
If you look at the stability tag of ghc libraries you will see that a
lot of them are marked as provisional (Network.URI for example) or
experimental (Control.Monad.Trans).
This may
On Mon, 19 Nov 2007, Mads [ISO-8859-1] Lindstrøm wrote:
It occurred to me that the voting could be implicit. That is, if 10
libraries/programs use library X, then library X gets 10 votes. Kind of
like Google PageRank for libraries.
It would be good if users could comment verbally. They could
On Thu, 22 Nov 2007, Peter Verswyvelen wrote:
worksFine =
if True
then putStrLn True
else putStrLn False
worksNOT = do
if True
then putStrLn True
else putStrLn False
worksAgain = do
if True
then putStrLn True
else putStrLn False
Of course the worksFine
On Thu, 4 Oct 2007, Don Stewart wrote:
The Haskell website has the rather strange motivational text:
Haskell is a general purpose, purely functional programming language
featuring static typing, higher order functions, polymorphism, type
classes, and monadic effects. Haskell
On Mon, 26 Nov 2007, Thomas Davie wrote:
On 26 Nov 2007, at 15:15, Henning Thielemann wrote:
On Thu, 4 Oct 2007, Don Stewart wrote:
The Haskell website has the rather strange motivational text:
Haskell is a general purpose, purely functional programming
language
featuring
On Mon, 26 Nov 2007, Andrew Coppin wrote:
apfelmus wrote:
But we'd probably need the glossary articles first before linking to
them :)
+12
I added added alpha, beta and eta conversion a while back. (And then
some kind soul corrected it because half of what I wrote was actually
I wonder whether it is a typical mistake of beginners
to write 'return' within a do-block (that is, not at the end)
and if it is possible to avoid this mistake by clever typing.
In a proper monad 'return' can be fused with subsequent actions,
and thus it is not necessary within a sequence of
On Mon, 26 Nov 2007, Jason Dusek wrote:
Among numeric types, it seems that only integer types are Bounded.
Maybe because IEEE format supports Infinity?
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On Tue, 27 Nov 2007, Thomas Davie wrote:
On 27 Nov 2007, at 14:44, David Menendez wrote:
On Nov 26, 2007 1:44 PM, Thomas Davie [EMAIL PROTECTED] wrote:
But the point is that this section of the site is the bit that's meant
to be an advertisement -- we're trying to encourage people to
On Tue, 27 Nov 2007 [EMAIL PROTECTED] wrote:
Hello,
I'm trying to program an implementation of the St. Petersburg game in
Haskell. There is a coin toss implied, and the random-number generation is
driving me quite mad. So far, I've tried this:
import Random
increment :: Int - Int
On Tue, 27 Nov 2007, Josh Lee wrote:
On Tue, 27 Nov 2007 14:41:59 -0500
Isaac Dupree [EMAIL PROTECTED] wrote:
Henning Thielemann wrote:
On Mon, 26 Nov 2007, Jason Dusek wrote:
Among numeric types, it seems that only integer types are Bounded.
Maybe because IEEE format
On Tue, 27 Nov 2007, Andrew Coppin wrote:
So, now I have a Haskell version that's only several hundred times
slower. Neither program is especially optimised, yet the C version is
drastically faster. This makes me sad. :-(
I think the C version is so much faster because it does not need
On Tue, 27 Nov 2007, Bit Connor wrote:
Actually, IEEE numbers are designed in such a way, that if you interpret
their bits as integer number, then 'succ' leads you to the next larger
representable number. Thus you only have to cast from Float or Double to
Int32 or Int64 respectively,
On Tue, 27 Nov 2007, Yitzchak Gale wrote:
Bit Connor wrote:
Also, a related question: How do you convert from Float - Double, and
the reverse? Only thing I could find is (fromRational . toRational)
which I also imagine to be slow, and I also wonder about accuracy.
realToFrac
added to
On Tue, 27 Nov 2007, apfelmus wrote:
More specifically, fact means something that you can easily check
yourself. Robust/maintainable/testable code are things you _can't_
easily check yourself without already learning the language.
+1
But shorter code is a fact you can easily check, for
On Wed, 28 Nov 2007, manu wrote:
Hello,
I'm trying to build diverse packages from Hackage with ghc 6.8.1,
they usually fail to build because of missing language extensions.
Sometimes I am unable to determine the proper name of the extension
missing in .cabal
I tend to slap {- #OPTIONS
On Wed, 28 Nov 2007, Robert Dockins wrote:
FWIW, I find the same phenomenon with Edison. I get very little feedback
about it positive or negative; I really have no idea how many people are
using it. I guess people are more willing to roll their own data structures
or use the standard libs.
On Thu, 29 Nov 2007, Ben Franksen wrote:
Thomas Schilling wrote:
I put up a draft page. Feel free to adjust it.
http://haskell.org/haskellwiki/FrontpageDraft
I like the current version better. It is /very/ difficult to pack in such a
short paragraph a list of the most important
On Wed, 28 Nov 2007, Chris Smith wrote:
data AD a = AD a a deriving Eq
instance Show a = Show (AD a) where
show (AD x e) = show x ++ + ++ show e ++ eps
instance Num a = Num (AD a) where
(AD x e) + (AD y f) = AD (x + y) (e + f)
(AD x e) - (AD y f)
On Thu, 29 Nov 2007, Henning Thielemann wrote:
On Wed, 28 Nov 2007, Chris Smith wrote:
diffNum:: Num b= (forall a. Num a= a - a) - b
- b
diffFractional :: Fractional b = (forall a. Fractional a = a - a) - b
- b
diffFloating :: Floating b = (forall
I thought operations like foldl' and drop must be very fast on arrays
(especially UArray) with appropriate pointer tricks, I mean pointer
incrementing instead of indexing for foldl' and a pointer into the array
for drop. Is it planned to add such functions? Ok, if foldl f x .
elems and listArray
On Thu, 29 Nov 2007, Simon Marlow wrote:
What I'd *really* like to see is a bunch of links on the front page leading
to pages that describe the main differences between Haskell and some other
language (C, Python, Java, C#, F#, ...). The easiest way to grasp what
Haskell is all about is by
On Thu, 29 Nov 2007, Bryan O'Sullivan wrote:
Henning Thielemann wrote:
I thought operations like foldl' and drop must be very fast on arrays
(especially UArray) with appropriate pointer tricks,
These kinds of functions are only much use on one-dimensional arrays,
which look sufficiently
On Fri, 30 Nov 2007, Daniel Fischer wrote:
Am Freitag, 30. November 2007 14:39 schrieb Henning Thielemann:
Is this thread still about the prime sieve? As I mentioned, I think one
can avoid the mutable array, because if there is only a small number of
array updates with much changes per
On Fri, 30 Nov 2007, Johan Tibell wrote:
On Nov 30, 2007 1:30 AM, Ivan Miljenovic [EMAIL PROTECTED] wrote:
Speaking of Stackless Python, its homepage (http://www.stackless.com/)
has a rather nice layout... maybe slightly less emphasis on the About
section, but there you've got the links,
On Thu, 29 Nov 2007, Thomas Hartman wrote:
but there's no risk using trace is there?
'trace' is really only for debugging. It should not appear in shipped
libraries or programs.
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I know there are Haskell people who are busy with hardware verification
and relational algebra.
(as indicated by
http://www.haskell.org/haskellwiki/Relational_algebra
http://www.haskell.org/haskellwiki/Applications_and_libraries/Hardware_verification
)
Is there a Haskell library
On Fri, 30 Nov 2007, Bulat Ziganshin wrote:
Hello Andrew,
Thursday, November 29, 2007, 9:43:48 PM, you wrote:
Fifth thing: better use an STUArray, don't drag IO in if it's not
necessary.
I don't understand the ST monad.
it's just a subset of IO monad, with renamed operations
On Fri, 30 Nov 2007, Ketil Malde wrote:
Bryan O'Sullivan [EMAIL PROTECTED] writes:
For higher dimensions, there are enough options in terms of
traversal direction and what exactly e.g. a fold should fold over
(single elements? lower-dimensional slices?) that a sensible API
doesn't
On Fri, 30 Nov 2007, Luke Palmer wrote:
But I can't figure out a good way to represent bodies in this world.
I considered:
newBody :: (Position,Velocity) - World - (Body,World)
Where Body is an ADT with an internal representation of an Integer or
something. The problem with this is that
On Tue, 4 Dec 2007, Dougal Stanton wrote:
On 04/12/2007, Felipe Lessa [EMAIL PROTECTED] wrote:
I always thought show was meant for returning a String that could be
used to recreate the original data if you copy-pasted it in your code
or if you used read (i.e. read . show == id). Reading
On Thu, 6 Dec 2007, Thomas Hartman wrote:
On a related note... is there some easy way to be sure that a program I am
compiling uses only haskell 98? (Because any pure haskell 98 should always
compile on yhc... right?)
You can for instance use 'haskell98' as dependent package instead of
On Fri, 7 Dec 2007, Simon Peyton-Jones wrote:
| And I think that the solution is not to make the language larger and larger
| everytime someone wants a feature but to give people the tools to provide
| features without language changes.
Of course that would be even better! (Provided of
On Fri, 7 Dec 2007, Andrew Coppin wrote:
Ian Lynagh wrote:
On Tue, Dec 04, 2007 at 03:07:01PM -0800, Ryan Ingram wrote:
Is there a reason why strictness is defined as
f _|_ = _|_
instead of, for example,
forall x :: Exception. f (throw x) = throw x
Errors and exceptions are
On Fri, 7 Dec 2007, Neil Mitchell wrote:
Hi
I want literate Haskell, but where the literate bit forming a document
is actually HTML, not latex. Does anyone have any idea how to go about
this?
The numeric-quest library was the first and only one that I have seen in
this style. I could only
On Sat, 8 Dec 2007, Bit Connor wrote:
On Dec 8, 2007 8:19 PM, Andrew Coppin [EMAIL PROTECTED] wrote:
Andrew Coppin wrote:
Well, for starters, take a look at KLogic.
http://alts.homelinux.net/shots/195-0.jpg
This is the kind of thing I'd like to end up with.
Such a GUI would also
On Mon, 10 Dec 2007, Dan Piponi wrote:
When someone comes to me and says I have this Python script that
scans through these directories and finds the files that meet these
criteria and generates a report based on this template, could I do it
better in Haskell? it'd be good to have a better
On Tue, 11 Dec 2007, Anthony Clayden wrote:
I agree with Henning that HAVING is a 'terrible hack', but then SQL
altogether is a terrible hack.
Somehow, yes.
As that paper points out, HAVING is unnecessary - it's just a filter on
the result set of group-by.
Yep.
It's crucial that in
On Mon, 10 Dec 2007, Paul Moore wrote:
On 10/12/2007, Henning Thielemann [EMAIL PROTECTED] wrote:
I raise my question once again: Must Haskell's tutorials be tailored to
impatient programmers? Does Haskell need quickdirty hackers?
Haskell is the most practical functional language I have
On Tue, 11 Dec 2007, ChrisK wrote:
I look at it this way: Every person who adds Haskell, however shallowly, to
their repertoire acts as an example that may spur others to learn Haskell,
perhaps deeply. And that is a win not because of language chauvinism, but
because of concept
On Tue, 11 Dec 2007, Jed Brown wrote:
Perhaps you are looking for storablevector which is a direct
generalization of bytestring from Word8 to any Storable. It is not in
hackage yet, but seems stable. There isn't a `lazy' version, but that
could be changed.
On Tue, 11 Dec 2007, John Lato wrote:
I've been working on a library to encode/decode audio files (wave,
aiff, etc.) to and from lazy bytestrings, and it's finally in a form
where I'm willing to share. It's available at
http://mml.music.utexas.edu/jwlato/HSoundFile/, lightly cabalized and
On Tue, 11 Dec 2007 [EMAIL PROTECTED] wrote:
The Haskell one is dominated by the technical terms, while the Python
one is by more generic features. Let's break them down:
Plese, not again. Did you follow the earlier phases of that thread?
___
On Wed, 12 Dec 2007, Mattias Bengtsson wrote:
I found myself writing this for an Euler-problem:
digits :: Int - [Int]
digits i | i 10= [i]
| otherwise = i `mod` 10 : digits ( i `div` 10 )
And i realised it was quite some time ago (before this function) i had
actually
On Wed, 12 Dec 2007, Emre Sahin wrote:
How do you think the description could be improved?
Why don't you let Haskell speak for itself?
Instead of putting such buzzwords nobody really understands (and
cares), put random problem descriptions and one-line solutions in
Haskell. Well
On Wed, 12 Dec 2007, Reinier Lamers wrote:
Back in my Introduction to Functional Programming course, Daan Leijen
demonstrated how to print integers in Haskell using function
composition. Something along the lines of:
printint :: Int - [Char]
printint = map chr . map (+0x30) . reverse . map
On Wed, 12 Dec 2007, apfelmus wrote:
gwern wrote:
Now, the Main Page on haskell.org is not protected, so I could just edit
in one of the better descriptions proposed, but as in my Wikipedia editing,
I like to have consensus especially for such visible changes.
Hey, why has the
On Wed, 12 Dec 2007, Bill Wood wrote:
On Wed, 2007-12-12 at 11:19 +, Andrew Coppin wrote:
. . .
...and normal programmers care about the Fibonacci numbers because...?
Seriously, there are many, many programmers who don't even know what
Fibonacci numbers *are*. And even I can't
On Fri, 14 Dec 2007, Henning Thielemann wrote:
Worst case analysis of AVL trees also leads to Fibonacci numbers, as far
as I remember.
The number of possibilities to arrange bricks of a certain width is also
Fibonacci number. In general I think that Fibonacci numbers serve as
simple non
On Wed, 12 Dec 2007, Don Stewart wrote:
ndmitchell:
A much simpler version:
main = print . length . words = getContents
Beautiful, specification orientated, composed of abstract components.
My thoughts too when reading the initial post was that it was all very
low level
On Mon, 17 Dec 2007, Nicholls, Mark wrote:
After many years of OOP though my brain is wired up to construct
software in that 'pattern'a problem for me at the moment is I cannot
see how to construct programs in an OO style in HaskellI know this
is probably not the way to approach
On Tue, 18 Dec 2007, Cristian Baboi wrote:
Haskell strengts as I see them:
- it is lazy with class
- it is strongly typed
- it has automatic memory management
- it has a standard library
- it has a compiler
- it is available on several platforms
- it has a community
- it is free
Is
On Tue, 18 Dec 2007, Benja Fallenstein wrote:
Hi Cristian,
On Dec 18, 2007 10:53 AM, Cristian Baboi [EMAIL PROTECTED] wrote:
- the lambda expressions can be written (input) but cannot be printed
(output)
Yes, since two different lambda expressions can denote the same function.
I
On Tue, 18 Dec 2007, Benja Fallenstein wrote:
Hi Henning,
On Dec 18, 2007 3:53 PM, Henning Thielemann
[EMAIL PROTECTED] wrote:
Since this was discussed already here, I summed it up in:
http://www.haskell.org/haskellwiki/Show_instance_for_functions
I find the discussion under
On Tue, 18 Dec 2007, Benja Fallenstein wrote:
Hi Henning,
On Dec 18, 2007 5:17 PM, Henning Thielemann
[EMAIL PROTECTED] wrote:
The mathematical definition of function I know of, says that functions
are special relations, and relations are sets of pairs. Their is nothing
about intension
On Thu, 20 Dec 2007, Alex Sandro Queiroz e Silva wrote:
Hallo fellow Brazilian,
Clerton Filho escreveu:
Hi,
I'm newbie in Haskell, and I have some doubts... In this programming
language, do we have storable values? Case affirmative, what are the
storable types in Haskell, and how
On Mon, 24 Dec 2007, Cristian Baboi wrote:
While reading the Haskell language report I noticed that function type is
not an instance of class Read.
I was told that one cannot define them as an instance of class Show
without breaking referential transparency or printing a constant.
f ::
I thought I understand monomorphism restriction. But it seems, I don't. I
have boilt down my problem to the following test. Don't try to make any
sense of it, it is just the smallest code I could come up with.
test :: (Integral a, RealFrac a) = a
test =
let c = undefined
in asTypeOf
On Tue, 25 Dec 2007, Felipe Lessa wrote:
On Dec 25, 2007 4:27 PM, Henning Thielemann
[EMAIL PROTECTED] wrote:
test :: (Integral a, RealFrac a) = a
test =
let c = undefined
in asTypeOf (round c) c
When compiling I get:
Compiling StorableInstance ( src
On Sat, 29 Dec 2007, Adam Langley wrote:
Some packages[1] have links on their Hackage pages to the haddock
generated documentation for each exported module[2]. However, many[3]
don't.
What's the secret to getting this generated documentation to work with
Hackage? Even packages for which
On Sun, 30 Dec 2007, Joost Behrends wrote:
A similar point: The tutorials teach, that = has a similar meaning than =
in
mathematics. But there is a big difference: it is not reflexive. The
the right side is the definition of the left. Thus x=y has still some kind
of
temporality, which
On Thu, 6 Dec 2007, Henning Thielemann wrote:
On Thu, 6 Dec 2007, Thomas Hartman wrote:
On a related note... is there some easy way to be sure that a program I am
compiling uses only haskell 98? (Because any pure haskell 98 should always
compile on yhc... right?)
You can for instance
On Thu, 3 Jan 2008, Achim Schneider wrote:
Henning Thielemann [EMAIL PROTECTED] wrote:
Sometimes I believed that I understand this reason, but then again I
do not understand. I see that left-associative (++) like in
((a0 ++ a1) ++ a2) ++ a3
would cause quadratic time
On Thu, 3 Jan 2008, Daniel Fischer wrote:
Am Donnerstag, 3. Januar 2008 14:48 schrieb Henning Thielemann:
Sometimes I believed that I understand this reason, but then again I do
not understand. I see that left-associative (++) like in
((a0 ++ a1) ++ a2) ++ a3
would cause quadratic
On Thu, 3 Jan 2008, Peter Verswyvelen wrote:
I believe type signatures are the very essence of Haskell documentation!
I'd much rather see a program with type signatures for functions and
little (or no) comments over programs with no type signatures and
ambigious comments (if any comments
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