On Aug 13, 2007, at 16:29 , Benjamin Franksen wrote:
Let's take the simplest example: Maybe. The effect in question is the
premature abortion of a computation (when Nothing is returned). And of
course Maybe sequences these effects, that's what you use it for: the
_first_ action to be
On Aug 14, 2007, at 11:17 , Dougal Stanton wrote:
Let us say, hypothetically, you had a bathroom without any reading
material. And having read all the Dilbert and Garfield you could
seriously stomach, decide you should educate yourself while on the
job. :-)
Sounds to me like you want a
On Aug 17, 2007, at 9:11 , rodrigo.bonifacio wrote:
envKey :: EnvItem (Key, a) - String
envKey EnvItem (key, value) = key
envValue :: EnvValue(Key, a) - a
envValue EnvItem (key, value) = value
But this is resulting in the error: [Constructor EnvItem must
have exactly 1 argument in
On Aug 21, 2007, at 22:13 , Twan van Laarhoven wrote:
Other rules that could be interesting are:
forall a b. fromInteger a + fromInteger b = fromInteger (a + b)
I don't think this will work, a and b have to be the same type.
--
brandon s. allbery [solaris,freebsd,perl,pugs,haskell] [EMAIL
On Aug 21, 2007, at 23:27 , Hugh Perkins wrote:
Hmmm, that's interesting. I'd never considered lack of typing to be a
good thing for system robustness before!
The old watchphrase (before Netscape and Microsoft abused it beyond
anyone's expectation) for Internet protocols was be liberal in
On Aug 25, 2007, at 14:43 , Andrew Coppin wrote:
Neil Mitchell wrote:
HI
Flippi (google: Haskell Flippi)
...and yet haskell.org uses WikiMedia? (Which is written in
something
bizzare like Perl...)
Yes, but WikiMedia is a result of years of work, Flippi is a lot
less.
Wikipedia
On Aug 29, 2007, at 23:34 , Hugh Perkins wrote:
Hmmm, random thought along similar lines, I mean I know the answer to
this thought is no, but I'm curious: could we get Haskell to run on a
graphics card???
I thought someone had done that recently as a graduate thesis.
--
brandon s. allbery
On Aug 30, 2007, at 2:34 , Radosław Grzanka wrote:
obsolete and Pocket PC is probably better target. Anyway, does anyone
else experience a feeling that at the time of buying yourself new
gadget you are already in deprecated zone? ;)
I've been feeling that way since 1982
--
brandon s.
On Aug 30, 2007, at 3:00 , Hugh Perkins wrote:
On 8/30/07, Miguel [EMAIL PROTECTED] wrote:
What about running Haskell on a PostScript printer? PostScript IS
Turing-complete.
Yes, because postscript printers are famous for being really fast ;-)
You youngsters don't remember when
On Aug 31, 2007, at 16:01 , Sterling Clover wrote:
In particular for a function -- n, m, etc or x, y, etc? What about
for f' defined in a let block of f? If I use x y at the top level I
need to use another set below -- is that where x' y' are more
appropriate, or x1, y1?
Usual style is
On Sep 2, 2007, at 2:08 , Peter Verswyvelen wrote:
But after reading http://en.wikipedia.org/wiki/
Fifth_generation_computer, it seemed to me that Prolog was a dead
language, having only pure theoretical purposes. Is this true?
Tell that to the order pricing system I wrote in Prolog for a
On Sep 4, 2007, at 5:02 , Miguel Mitrofanov wrote:
It depends on arbitrary restrictions on what constitutes an
(boolean) expression, something that is anathema to
functional programmers :-) Spot the language:
while if E
then S; F
else False
fi
do T
od
It reminds me of a
On Sep 5, 2007, at 6:47 , Ketil Malde wrote:
On Wed, 2007-09-05 at 09:56 +0100, Simon Peyton-Jones wrote:
Good point. Not so easy for multi-parameter type classes! E.g. No
instance for (Bar String Int). So we could have
String is not an instance of class Foo -- single param
On Sep 7, 2007, at 14:37 , Albert Y. C. Lai wrote:
Brent Yorgey wrote:
Then one day he met someone else who said she was also a race car
driver, but her car was different -- she called it a Haskar. It
had a top speed of 400 miles per hour, no steering wheel (you just
lean whichever way
On Sep 9, 2007, at 9:09 , Peter Verswyvelen wrote:
I think that the benefits of prefix or postfix symbolic operators
were not worth dispensing with the comfortable section syntax.
Well, that's personal I guess, but I would prefer the syntax (? /
100) and (100 / ?), which is just a single
On Sep 10, 2007, at 1:47 , Stuart Cook wrote:
On 9/10/07, PR Stanley [EMAIL PROTECTED] wrote:
--count occurrences of chars in string
countCS :: [Char] - [(Char, Int)]
countCS xs = [(x, (countC x xs)) | x - [' '..'z'], (countC x xs)
0]
A few things to note:
My naive take on it:
import
On Sep 11, 2007, at 7:01 , Jules Bean wrote:
The actual format used by Data.Binary is not explicitly described
in any standard (although in most cases it's moderately obvious,
and anyone can read the code), and it's not formally guaranteed
that it will never change in a later version
On Sep 12, 2007, at 10:18 , Andrea Rossato wrote:
supposed that, in a Linux system, in an utf-8 locale, you create a
file
with non ascii characters. For instance:
touch abèèè
Now, I would expect that the output of a shell command such as
ls ab*
would be a string/list of 5 chars. Instead I
On Sep 14, 2007, at 21:35 , L.Guo wrote:
Thanks for your advice about thunk, though I do not understand *thunk*
very well. Is there any other discriptions about thunk ?
A thunk is, in general, a piece of code which represents a
suspended or delayed action. In Haskell, it represents a lazy
On Sep 19, 2007, at 23:17 , PR Stanley wrote:
length = foldr (. n . 1 + n) 0
Any idea how to define length with foldr. The above definition
doesn't make much sense.
Still fighting with the botched OCR?
length = foldr (\_ n - 1 + n) 0
--
brandon s. allbery
On Sep 20, 2007, at 0:03 , PR Stanley wrote:
\_ n - 1 + n
\_ - (\n - 1 + n)
The outcome seems to be identical. is there a substantive
difference between the two definitions?
The second one seems to be more expressive of the currying principle.
Any thoughts?
I *think* the former is
On Sep 20, 2007, at 0:16 , PR Stanley wrote:
I must confess that the use of \_ had me a little confused at
first but thinking about it I can see that it makes perfect sense
to have an argument or a wildcard character for any value.
Sure. Remember, arguments are pattern matches in Haskell
On Sep 25, 2007, at 5:48 , Andrew Coppin wrote:
Dougal Stanton wrote:
In this instance I would suggest:
(1) Text.Printf
You've got to be kidding... I went to all the trouble of learning a
scary logic programming language [sic] just to avoid that damned
printf() function! :-/
Enh.
On Sep 25, 2007, at 5:56 , Andrew Coppin wrote:
More seriously, I have no idea how you'd implement this in Haskell.
Presumably the standard show instance for Int, Double, etc. is in
native C? You could probably reimplement it in Haskell for the
integer case, but not for floating-point...
On Sep 25, 2007, at 5:45 , Andrew Coppin wrote:
Still, since Haskell seems to be devoid of any more advanced way of
formatting numbers beyond low-level character jiggling...
Text.Printf.printf is your friend.
--
brandon s. allbery [solaris,freebsd,perl,pugs,haskell] [EMAIL PROTECTED]
On Sep 25, 2007, at 6:55 , Andrew Coppin wrote:
This is why I found it so surprising - and annoying - that you
can't use a 2-argument function in a point-free expression.
You can, it just requires more juggling. Play around with
lambdabot's @pl for a bit.
--
brandon s. allbery
On Sep 25, 2007, at 7:25 , Andrew Coppin wrote:
Chaddaï Fouché wrote:
2007/9/25, Andrew Coppin [EMAIL PROTECTED]:
printf don't always perform IO : if you ask it for a String it will
happily turn into sprintf for you, if you use it in the IO
Monad, it
will indeed perform IO, but there's
On Sep 25, 2007, at 7:24 , Andrew Coppin wrote:
which *just happens* to be what we want. But in the general case
where you want
f3 (f2 (f1 x y z))
there's nothing you can do except leave point-free.
You mean leave point-ful.
And the point-free version of that is (((f3 . f2) .) .) . f1
On Sep 27, 2007, at 14:14 , bbrown wrote:
instance Show SimplePlayer where
show a = Simple posX [ ++ show a{posX} ++ ]
instance Show SimplePlayer where
show a = Simple posX [ ++ show (posX a) ++ ]
You might also want to consider deriving(Show).
--
brandon s. allbery
On Sep 30, 2007, at 11:57 , PR Stanley wrote:
Well, note that foldr takes a function of x, which produces a
function of xs. This function of xs either conses x onto it, or
leaves it unchanged. We can write this down explicitly by
removing the xs parameter and just writing what
On Sep 30, 2007, at 14:39 , Peter Verswyvelen wrote:
This is of course very easy to do manually, but does a command line
tool exist for extracting source code from literate Haskell files?
unlit in the GHC library directory?
--
brandon s. allbery [solaris,freebsd,perl,pugs,haskell] [EMAIL
On Oct 1, 2007, at 21:59 , Björn Buckwalter wrote:
Dear all,
I'm getting a rather unfriendly error when trying to load a plugin
with hs-plugins:
my_program: Ix{Int}.index: Index (65536) out of range ((0,7))
This tends to mean that hs-plugins doesn't understand the format of
the .hi
On Oct 2, 2007, at 9:52 , Alex Queiroz wrote:
(parseDottedList ls) | (parseProperList ls)
I've factored out the common left sub-expression in
parseLeftList. The problem is that ... is a valid identifier so when
inside the left of the list the parser sees a single dot, it tries to
match
On Oct 2, 2007, at 10:36 , Alex Queiroz wrote:
This does not work. The parser chokes in parseLeftList, because
it finds a single dot which is not the beginning of
Sorry, just woke up and still not quite tracking right, so I modified
the wrong snippet of code. The trick is to
On Oct 2, 2007, at 21:12 , Isaac Dupree wrote:
Stefan O'Rear wrote:
On Tue, Oct 02, 2007 at 11:05:38PM +0200, Johan Tibell wrote:
I do not believe that anyone was seriously advocating multiple
blessed
encodings. The main question is *which* encoding to bless. 99+
% of
text I encounter is
On Oct 5, 2007, at 12:33 , Henning Thielemann wrote:
http://www.henning-thielemann.de/CHater.html#CvsM3_ControlFlow
I can has English? :)
If the first large table is any indication, though, we may need to
define inconsistent. C syntax shown there is quite consistent;
what it isn't, is
On Oct 10, 2007, at 20:14 , Michael Vanier wrote:
I haven't been following this discussion closely, but here's an
idea: use reverse psychology.
Haskell -- You're probably not smart enough to understand it.
Nothing like appealing to people's machismo to get them interested.
Haskell
All these questions are actually Windows-centric; the answers are
different on Unix.
On Oct 12, 2007, at 13:21 , Andrew Coppin wrote:
I notice that getDirectoryContents appears to return its results in
alphabetical order. Is this behaviour actually guaranteed?
There is no guarantee,
On Oct 12, 2007, at 14:26 , Andrew Coppin wrote:
pierre wrote:
Wouldn't it be better to write not just a visualization plugin,
but a whole player from scratсh? :-)
...this idea also occurred to me. ;-)
Why, do *you* know how to decode MP3 data?
Don't Do That. Use someone else's
On Oct 12, 2007, at 16:25 , Tim Chevalier wrote:
On 10/12/07, Steve Schafer [EMAIL PROTECTED] wrote:
On Fri, 12 Oct 2007 13:03:16 -0700, you wrote:
It's different because the property that (for example) head
requires a
nonempty list is checked at compile time instead of run time.
No, I
On Oct 12, 2007, at 18:35 , Albert Y. C. Lai wrote:
You are not expected to be convinced this, but it seems
continuations completely characterize system programming. :)
Didn't someone already prove all monads can be implemented in terms
of Cont?
(here you see why schemers are so wedded
On Oct 12, 2007, at 19:26 , Tim Chevalier wrote:
On 10/12/07, Brandon S. Allbery KF8NH [EMAIL PROTECTED] wrote:
You two are talking past each other. You're talking about dependent
typing, etc. Steve's complaint is not about dependent typing; he's
saying Andrew is looking for something
On Oct 12, 2007, at 17:38 , Lihn, Steve wrote:
Installing: --prefix=~/cabal/lib/haddock-0.8/ghc-6.4
This looks suspicious to me: the ~ metacharacter is only
understood by shells, and only in certain circumstances (i.e. only at
the beginning of a word, not after a =), and by the time
On Oct 12, 2007, at 19:42 , Dan Piponi wrote:
On 10/12/07, Brandon S. Allbery KF8NH [EMAIL PROTECTED] wrote:
He wants to write entire programs in the type system,
something like the crazies who write programs in C++ templates such
that template expansion does all the work at compile time
On Oct 13, 2007, at 3:51 , Aaron Denney wrote:
On 2007-10-12, Brandon S. Allbery KF8NH [EMAIL PROTECTED] wrote:
On Oct 12, 2007, at 17:38 , Lihn, Steve wrote:
Installing: --prefix=~/cabal/lib/haddock-0.8/ghc-6.4
This looks suspicious to me: the ~ metacharacter is only
understood
On Oct 13, 2007, at 6:52 , ntupel wrote:
On Fri, 2007-10-12 at 20:25 -0700, Stefan O'Rear wrote:
On Sat, Oct 13, 2007 at 12:09:57AM +0200, ntupel wrote:
setup :: (Ord a, IArray a2 a, IArray a1 e, Num a) = [e] - [a] -
(a1 Int e, a1 Int e, a2 Int a)
calcAlias :: (Ord e, Num e, IArray a e, Ix
On Oct 13, 2007, at 11:40 , ntupel wrote:
On Sat, 2007-10-13 at 09:56 -0400, Brandon S. Allbery KF8NH wrote:
Now you need to start forcing things; given laziness, things tend to
only get forced when in IO, which leads to time being accounted to
the routine where the forcing happened
On Oct 13, 2007, at 13:30 , ntupel wrote:
On Sat, 2007-10-13 at 12:42 -0400, Brandon S. Allbery KF8NH wrote:
Your apparently simple StdGen argument is actually a sort of program
state (represented by unevaluated thunks, not by a state monad; see
below) which gets altered with every invocation
On Oct 14, 2007, at 17:54 , ntupel wrote:
Now my problem still is, that I don't know how to speed things up. I
tried putting seq and $! at various places with no apparent
improvement.
Maybe I need to find a different data structure for my random
module and
lazy lists are simply not
On Oct 14, 2007, at 22:54 , Richard A. O'Keefe wrote:
The really amazing thing about the IO Monad in Haskell is that
there *isn't* any magic going on. An level of understanding
adequate for using the I/O and State monads stuff (that is,
adequate for practically anything analogous to what you
On Oct 15, 2007, at 7:01 , Yitzchak Gale wrote:
But I think we are still at the stage where a programmer
who wants practical results is better off starting out
by learning how to use monads in practice, not by
delving into category theory.
No argument from a Haskell standpoint. Still, when
On Oct 15, 2007, at 7:02 , [EMAIL PROTECTED] wrote:
IO is different, you *cannot* make it non-monadic.
Not really true; it's just much more painful. You just e.g.
explicitly do what the ghc library's implementation of IO does:
construct a chain of functions with an opaque (and
On Oct 15, 2007, at 7:02 , david48 wrote:
On 10/15/07, Peter Verswyvelen [EMAIL PROTECTED] wrote:
Yes, exactly, but how does one call the way of programming without
monads / do notation then, explicitly passing the object? Does this
approach have a name? Or just non-monadic style?
the
On Oct 15, 2007, at 7:59 , Felipe Lessa wrote:
On 10/15/07, apfelmus [EMAIL PROTECTED] wrote:
lasts :: Int - [a] - [a]
lasts n xs = head $ [x | (x,[]) - zip (tails xs) (tails $ drop
n xs)]
(...)
main n = print . sum . map read . lasts n . lines = getContents
But that's a a
On Oct 15, 2007, at 9:48 , Brandon S. Allbery KF8NH wrote:
On Oct 15, 2007, at 7:02 , [EMAIL PROTECTED] wrote:
IO is different, you *cannot* make it non-monadic.
Not really true; it's just much more painful.
Expanding on this slightly: the neat thing about Haskell's monads
On Oct 15, 2007, at 13:32 , Peter Verswyvelen wrote:
[EMAIL PROTECTED] wrote:
Yes, *different approach*. So, there *are* differences.
Compilers, anyway,
are special applications. I wanted to see - responding to Brandon
- a
normal Haskell program, which does IO without monads, that't all.
On Oct 15, 2007, at 19:00 , ChrisK wrote:
Brandon S. Allbery KF8NH wrote:
Use the source of unsafePerformIO as an example of how to write code
which passes around RealWorld explicitly, but without
unencapsulating it
like unsafePerformIO does.
The main problem here, I think
I actually got this done several hours ago, but my DSL is being
annoying tonight...
Anyway, here's a simple example of how to do explicit/non-monadic I/O
in GHC. (It *only* works in GHC; other compilers have different
internal implementations of IO.) I specifically modeled it to
On Oct 16, 2007, at 4:21 , Ketil Malde wrote:
The major/minor scheme has worked nicely for .so for ages.
i'm not so sure about that. it may be better than alternatives,
but [..]
Also, it sees a lot of testing, at least in current Linux
distributions. The point is that the end-user
On Oct 16, 2007, at 9:01 , Bayley, Alistair wrote:
From: Simon Marlow [mailto:[EMAIL PROTECTED]
The lexicographical ordering would make 10.0 9.3. In
general, A.B C.D
iff A C or A == C B D. When we say the latest
version we mean
greatest, implying that version numbers increase with
On Oct 16, 2007, at 21:40 , Richard A. O'Keefe wrote:
F_GETFD and F_SETFD are the things to look for; FD_CLOEXEC is a fancy
way of saying 1 in historic UNIXes. The OSF/1 /usr/include/sys/
fcntl.h says that FD_CLOEXEC is POSIX REQUIRED. This facility is
most certainly part of the Single Unix
On Oct 17, 2007, at 0:39 , Donn Cave wrote:
On Oct 16, 2007, at 7:31 PM, Brandon S. Allbery KF8NH wrote:
I could dig for official confirmation, but this is my
understanding of both POSIX and SUS, and portable C programs
generally #define FD_CLOEXEC to 1 if it doesn't already exist
On Oct 17, 2007, at 1:32 , Donn Cave wrote:
On Oct 16, 2007, at 9:52 PM, Brandon S. Allbery KF8NH wrote:
Either implementation causes problems; security folks tend to
prefer that all file descriptors other than 0-2 (0-4 on Windows?)
be closed, and 0-2(4) be forced open (on /dev/null
On Oct 17, 2007, at 22:25 , Dan Weston wrote:
I find the mathematics is more accurate on
http://www.conservapedia.com
Their facts get checked by the Almighty Himself! ;)
I Kings 7:23? :p
--
brandon s. allbery [solaris,freebsd,perl,pugs,haskell] [EMAIL PROTECTED]
system administrator
On Oct 18, 2007, at 4:57 , Simon Marlow wrote:
depend on API versions (including minor versions) that you haven't
tested, or (b) use explicit import lists and allow minor version
changes only. Incedentally, this reminds me that GHC should have a
warning for not using explicit import lists
On Oct 19, 2007, at 15:14 , Andrew Coppin wrote:
Peter Verswyvelen wrote:
I find it a petty the library does not work with GHCi :-( It has
to do with the threaded RTS I guess. Any hints how I could fix this?
Yeah, lots of things seem to dislike running in GHCi. (I'm guessing
this is to
On Oct 19, 2007, at 12:11 , Sebastian Sylvan wrote:
On 19/10/2007, Kalman Noel [EMAIL PROTECTED] wrote:
data ExistsNumber = forall a. Num a = Number a
I'm without a Haskell compiler, but shouldn't that be exists a.?
The problem is that exists is not valid in either Haskell 98 or any
On Oct 18, 2007, at 19:53 , John Meacham wrote:
On Thu, Oct 18, 2007 at 02:31:10AM +0100, PR Stanley wrote:
Do you trust mathematical materials on Wikipedia?
Certainly! I honestly think wikipedia is one of man's greatest
achievements, and it is just in its infancy.
For what it's worth,
On Oct 20, 2007, at 15:05 , Andrew Coppin wrote:
I can quite happily construct a program which, given the first
line, yields the last line. But getting it to print all the
intermediate steps is harder. And, like I said, when something is
hard in Haskell, it usually means you're doing it
On Oct 21, 2007, at 6:29 , Jon Fairbairn wrote:
No, they (or at least links to them) typically are that bad!
Mind you, as far as fragment identification is concerned, so
are a lot of html pages. But even if the links do have
fragment ids, pdfs still impose a significant overhead: I
don't want
On Oct 21, 2007, at 6:41 , Peter Hercek wrote:
Brandon S. Allbery KF8NH wrote:
On Oct 19, 2007, at 12:11 , Sebastian Sylvan wrote:
On 19/10/2007, Kalman Noel [EMAIL PROTECTED] wrote:
data ExistsNumber = forall a. Num a = Number a
I'm without a Haskell compiler, but shouldn't
On Oct 21, 2007, at 14:40 , Maurí cio wrote:
I like Haskell, and use it as my main
language. However, compiling a Haskell program
usually takes a lot of memory and CPU. So I was
To some extent this is just a matter of Haskell not having been
around that long ago: as ghc evolves, it's been
On Oct 21, 2007, at 15:21 , Maurí cio wrote:
Of course. But I think of somethink like a Intel 386 with 4MB
of memory.
It's kinda surprising to me how many people think that just because
current/modern implementations of things use memory wastefully, this
is somehow mandatory. When
On Oct 21, 2007, at 15:31 , [EMAIL PROTECTED] wrote:
Mauricio writes:
... But I think of somethink like a Intel 386 with 4MB
of memory.
It seems you decided to ignore my message. OK.
Whoa there! Why assume malice? I got both his quoted response and
your message at about the same time,
On Oct 21, 2007, at 21:31 , Maurí cio wrote:
Anyway, what I would like would be a theoretical
answer. Is there something fundamentally diferent
between a C compiler and a Haskell one that makes
the former fits into 30Kb but not the other? If
I am not sure *modern* C would have fit into 30KB.
On Oct 22, 2007, at 4:09 , manu wrote:
However looking at the number of permutations (26! =
40329146112660563558400), quickly dampened my enthusiasm...
There must be some algorithm (dynamic programming ?), that cuts
down the number of calculations involved in order to find the right
On Oct 22, 2007, at 22:41 , PR Stanley wrote:
f x = x
x :: a
f x :: b
therefore f :: a - b
x = a and x = b
therefore a = b
therefore f :: a - a
Simple mappings are easy to work out. It's the more detailed stuff
I'm not sure about.
f g x y = g x (y x)
I think you're looking for
On Oct 25, 2007, at 13:04 , Derek Elkins wrote:
Just use unsafeInterleaveIO in the obvious definition to read all the
keys. That said, it's not called unsafeInterleaveIO for no reason.
I think it might actually be safe in this case: if the file changes
out from under your lazy I/O, far
On Oct 25, 2007, at 14:21 , Ryan Ingram wrote:
On 10/25/07, Brandon S. Allbery KF8NH [EMAIL PROTECTED] wrote:
I think it might actually be safe in this case: if the file changes
out from under your lazy I/O, far worse things happen in the gdbm
library layer than in the unsafe-IO Haskell
On Oct 29, 2007, at 3:36 , Tim Newsham wrote:
or go through the trouble of defining a bunch of binops
f + g = liftM2 (+) f g
n + g = return n + g
f + n = f + return n
read' = liftM read
This looks a lot like Control.Applicative to me.
--
brandon s. allbery
On Nov 1, 2007, at 13:47 , David Carter wrote:
else rest - readdirAll d
You need another do here to use the - syntax.
--
brandon s. allbery [solaris,freebsd,perl,pugs,haskell] [EMAIL PROTECTED]
system administrator [openafs,heimdal,too many hats] [EMAIL PROTECTED]
electrical and
On Nov 2, 2007, at 6:35 , apfelmus wrote:
during function evaluation. Then, we'd need a purity lemma that
states that any function not involving the type *World as in- and
output is indeed pure, which may be a bit tricky to prove in the
presence of higher-order functions and polymorphism.
On Nov 2, 2007, at 11:51 , Jonathan Cast wrote:
I will grant that hiding *World / RealWorld# inside IO is cleaner
from a practical standpoint, though. Just not from a semantic one.
On the contrary. GHC's IO newtype isn't an implementation of IO in
Haskell at all. It's an implementation in
On Nov 2, 2007, at 17:35 , Andrew Coppin wrote:
These are the things I'm thinking about. Is there some deep
theoretical reason why things are the way they are? Or is it merely
that nobody has yet had time to make something better? ByteString
solves the problem of text strings (and raw
On Nov 3, 2007, at 5:34 , Andrew Coppin wrote:
(BTW, anybody have any clue what's happening with stream fusion? I
remember reading the paper saying hey, this is how it works and
it's cool and we're going to try to replace the whole list library
with new stream implementations, but that's
On Nov 5, 2007, at 16:21 , Alex Young wrote:
C:\Users\Alex\Documents\HaskellLearning\MonteCarloghc BetterPi.hs
C:\Users\Alex\Documents\HaskellLearning\MonteCarlomain.exe 100
Stack space overflow: current size 8388608 bytes.
Use `+RTS -Ksize' to increase it.
But:
On Nov 5, 2007, at 15:46 , Andrew Coppin wrote:
You can spark a thread for each computation of fn, like such:
writeArray framebuffer p `parApp` fn p
where
parApp f x = x `par` f x
Hmm, that may be a little *too* fine-grained. (But then, just
because I spark 175,862 threads doesn't mean
On Nov 6, 2007, at 0:16 , Maurí cio wrote:
Actually, what I want is to select a region of
text from emacs and get back the result of that
evaluated as haskell code. So, I need something
that is fast to type, since I'll use it all the
time. Maybe I should learn how to write a small
shell script
On Nov 6, 2007, at 0:48 , Maurí cio wrote:
Brandon S. Allbery KF8NH escreveu:
On Nov 6, 2007, at 0:16 , Maurí cio wrote:
Actually, what I want is to select a region of
text from emacs and get back the result of that
evaluated as haskell code. So, I need something
that is fast to type, since
On Nov 9, 2007, at 15:01 , Andrew Coppin wrote:
4. Not actually related to exceptions, but doesDirectoryExist C:\
yields False. (Even though getDirectoryContents C:\ yields the
correct result.) So I can't even use that to filter out invalid
directory names.
This is an ancient and
On Nov 11, 2007, at 12:16 , Andrew Coppin wrote:
However, it seems the general point of confusion is that writing
(say) a minimally-working C compiler intuitively seems quite easy
(after all, C is an extremely low-level language), whereas the
constructs in Haskell bear no resemblence to
On Nov 11, 2007, at 17:26 , [EMAIL PROTECTED] wrote:
Andrew Coppin writes:
Brent Yorgey wrote:
Expressiveness certainly makes it easier, but nothing (other
than
sanity...) stops you from writing a Haskell compiler in, say,
COBOL. *I* would stop you. Friends don't let friends
On Nov 13, 2007, at 13:32 , Dan Piponi wrote:
On Nov 13, 2007 3:00 AM, Simon Peyton-Jones [EMAIL PROTECTED]
wrote:
Dan, can you suggest any words we could add to the
documentation that would have prevented you stumbling?
I guess the thing that would have helped best would
On Nov 14, 2007, at 3:28 , Simon Peyton-Jones wrote:
I agree that an informative error message is worth 100 manual
pages. The trouble is that at this stage GHCi doesn't even *know*
that 'x' ever existed, because it's not mentioned in the interface
file, so it's hard to do even give the
On Nov 14, 2007, at 21:50 , Albert Lee wrote:
dotp :: Num a = [:a:] - [:a:] - a
You're forcing Num a = a here, whereas the list one probably
specializes to Integer. Seems like a bad way to go to me;
polymorphism is expensive. (Whether it's *that* expensive, I
couldn't tell you.)
--
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 a similar detour through strings.
fromEnum and/or toEnum
On Nov 19, 2007, at 15:13 , Neil Mitchell wrote:
- The packages seem to be of quite variable quality. Some are
excellent,
some are rather poor (or just not maintained any more).
The problem is that only one person gets to comment on the quality of
a library, the author, who is about the
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 not refer to what most people care about; the experimental
On Nov 19, 2007, at 16:50 , Henning Thielemann wrote:
On Mon, 19 Nov 2007, Brandon S. Allbery KF8NH wrote:
fromEnum and/or toEnum are helpful for this kind of thing, and I am
occasionally tempted to bind cast = toEnum . fromEnum because I
need it so much.
Really? I'd like to know which
On Nov 19, 2007, at 17:10 , Brandon S. Allbery KF8NH wrote:
CTime; POSIX allows (or used to allow) it to be a floating type in
order to allow some non-UNIXlikes to represent POSIX times. But
given that CTime is Enum, Foreign.C.Types already violates this; so
why isn't it
Hrm
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