Hi
Prelude :b Control.Concurrent.MVar
module 'Control.Concurrent.MVar' is not interpreted
:b now defaults to :breakpoint, you want :browse
Thanks
Neil
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On Friday 30 November 2007 00:31, Justin Bailey wrote:
I represent the automata as an array of integers, where each bit
represents a cell.
Mathematica uses a single arbitrary-precision integer to represent each
generation of a 1D automaton. The rules to derive the next generation are
compiled
Yitzchak Gale [EMAIL PROTECTED] writes:
Guido is clearly not rejecting functional influences
on Python, he is supporting them. But he feels that
these specific instances do not fit in.
I read some of his statements, and find that I disagree vehemently.
But I wonder if partial evaluation is
On Nov 30, 2007 6:03 PM, Justin Bailey [EMAIL PROTECTED] wrote:
On Nov 29, 2007 9:11 PM, Jon Harrop [EMAIL PROTECTED] wrote:
Mathematica uses a single arbitrary-precision integer to represent each
generation of a 1D automaton. The rules to derive the next generation are
compiled into
On Thu, 2007-11-29 at 23:56 +0100, Ben Franksen wrote:
Duncan Coutts wrote:
On Wed, 2007-11-28 at 21:00 +0100, Thomas Schilling wrote:
On Wed, 2007-11-28 at 20:46 +0100, Ben Franksen wrote:
[EMAIL PROTECTED]: .../software/haskell cd cabal
[EMAIL PROTECTED]: .../haskell/cabal
lemming:
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
Duncan Coutts wrote:
Apropos beta-testing, cabal-1.3 seems to have introduced an incompatible
API change; for instance, it can't build MissingH any longer.
Actually it was 1.2.x that made this change.
Ok. I realized it wasn't 1.3 as I remarked later:
One install of cabal-install later:
Paul Moore wrote:
On 28/11/2007, Ben Franksen [EMAIL PROTECTED] wrote:
It was fun, too. For instance, the OP's question reminded me of a little
generic wrapper I wrote -- more or less for my own amusement -- during
the course of this project. It outputs dots during an operation that
might
Hello,
0) All work being done on cygwin. Version 6.8.1 of ghc.
1) I ran runhaskell Setup.lhs configure and did a tail -f config.log
in order to follow the config process.
2) Next I did the build runhaskell Setup.lhs build but there were
many include files referenced in HsUnix.h
It seems you've already figured this out, but here's a quick counterexample:
{-# LANGUAGE ExistentialQuantification, RankNTypes #-}
module Box where
data Box = forall a. B a
--mapBox :: forall a b. (a - b) - Box - Box -- incorrect type
mapBox f (B x) = B (f x)
then:
boxedInt :: Box
Bulat Ziganshin wrote:
Hello Neil,
Friday, November 30, 2007, 1:32:25 AM, you wrote:
1. For certain tasks, there are multiple possible packages, and it's not
really clear which one to go for. Having more than one choice is good.
This can be solved easily using blogs. If you
Bulat Ziganshin wrote:
Hello Andrew,
Thursday, November 29, 2007, 11:51:32 PM, you wrote:
This is one of the more frustrating aspects of Haskell. It's not that
nobody has written DB bindings - they most certainly have. It's not that
nobody has written compression or cryptography bindings -
Brandon S. Allbery KF8NH wrote:
On Nov 29, 2007, at 17:13 , Thomas Hartman wrote:
but there's no risk using trace is there?
If you're doing any other I/O, you may be surprised by where the trace
output shows up relative to it.
How about if the I/O is to write to a different stream?
There seems to be three salient benefits of using arrows, as I read the
Abstract and Introduction of Benjamin Lerner, Arrow Laws and Efficiency
in Yampa, 2003,
http://zoo.cs.yale.edu/classes/cs490/03-04a/benjamin.lerner/
1) The discipline of using arrows assists in avoiding space-leaks
The
On Nov 29, 2007 9:11 PM, Jon Harrop [EMAIL PROTECTED] wrote:
Mathematica uses a single arbitrary-precision integer to represent each
generation of a 1D automaton. The rules to derive the next generation are
compiled into arithmetic operations on the integer. The offloads all such
work onto
On Nov 29, 2007 4:45 PM, Felipe Lessa [EMAIL PROTECTED] wrote:
Why don't you use an UArray of Bools? They're implemented as bit
arrays internally, AFAIK (e.g. see
http://www.haskell.org/haskellwiki/Shootout/Nsieve ). And then you
would get rid of a lot of shifts and masks in your code --
I think your integrate function looks like a good idea:
integrate :: TimeStep - World - World
For bodies, I think you should have a BodyID type, and then to add a
body to the world you could have a function:
newBody :: (Position, Velocity) - World - (BodyID, World)
To delete a body:
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 30 Nov 2007, [EMAIL PROTECTED] wrote:
Sure. To be more specific, here's the contract I would really like.
1. You need to pass in a polymorphic function a - a, where a is, at
*most*, restricted to being an instance of Floating. This part I can
already express via rank-N types. For
Laurent Deniau escreveu:
Maurício wrote:
Hi,
I'm learning about categories using Saunders
Mac Lane book. I'm also learning French. Do
you guys know of a nice French mailing list,
or forum, where people discuss about
categories (and where beginners are
accepted)?
newsgroup: fr.sci.math
a+,
Bulat Ziganshin wrote:
Hello Andrew,
Friday, November 30, 2007, 12:10:16 AM, you wrote:
I don't understand the ST monad.
From what I can tell, it's not definable without using strange language
extensions. (I don't really like using things where it's unclear why it
works.)
Justin Bailey wrote:
On Nov 29, 2007 9:11 PM, Jon Harrop [EMAIL PROTECTED] wrote:
Mathematica uses a single arbitrary-precision integer to represent each
generation of a 1D automaton. The rules to derive the next generation are
compiled into arithmetic operations on the integer. The offloads
I really like the friendly look of Ruby's homepage:
http://www.ruby-lang.org/en/
* There's an interpreter download button in a high visibility position.
* Visible news.
* It's pretty!
* A very short introduction. Ruby is...
... which is so generic, that we can copy it to the
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 update, it should be efficient enough
to copy the
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,
I'm currently working on idioms for game programming using FRP. After
going through several representations of physics as arrows[1] I
decided that physics objects must not be implemented as arrows,
because introducing new arrows in the middle of a computation[2] leads
to ugly pain.
So far the
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
Maurício wrote:
Hi,
I'm learning about categories using Saunders
Mac Lane book. I'm also learning French. Do
you guys know of a nice French mailing list,
or forum, where people discuss about
categories (and where beginners are
accepted)?
newsgroup: fr.sci.math
a+, ld.
Gracjan Polak wrote:
My program is eating too much memory:
copyfile source.txt dest.txt +RTS -sstderr
Reading file...
Reducing structure...
Writting file...
Done in 20.277s
1,499,778,352 bytes allocated in the heap
2,299,036,932 bytes copied during GC (scavenged)
1,522,112,856 bytes copied
On Nov 28, 2007 11:07 PM, Maurício [EMAIL PROTECTED] wrote:
Sorry, I don't agree. I try to write things in a
way that when you read it you can get an intuition
on why it's doing what it's doing; even when the
That's what comment are for :)
generate. So, instead of checking if threads have
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
The Haskell code works with arbitrary precision
Integer, the C code with a fixed size int.
This is also a work for a library (BTW like Haskell does), you can use
gmp or mpfr. This will just add one line to store x/2 in y and avoid its
recomputation. You will also have to switch from intset
Claus Reinke [EMAIL PROTECTED] writes:
you might find it easier to use GHCi's :browse command
While ghc -e works, this no longer work within GHCi?
Prelude :b Control.Concurrent.MVar
module 'Control.Concurrent.MVar' is not interpreted
-k
--
If I haven't seen further, it is by standing in
Hello Sebastian,
Friday, November 30, 2007, 11:31:22 AM, you wrote:
I don't see Data.Array.Base documented anywhere. (How did you know it
exists?)
i use library sources as reference. it allows to study implementation
and learn good programming style
--
Best regards,
Bulat
Sebastian Sylvan wrote:
On Nov 29, 2007 9:10 PM, Andrew Coppin [EMAIL PROTECTED] wrote:
How do you avoid accidentally recomputing the list multiple times?
What do you mean? It's exactly the same as your original program but
with ST instead of IO? Why would it get accidentally
On Thu, Nov 29, 2007 at 04:25:43PM -0800, Dan Weston wrote:
I must be missing something, because to me the contract seems to be much
simpler to express (than the Functor + Isomorphism route you seem to me
to be heading towards):
...
diff f a = if dx == dx' then error Zero denom else dydx
Am I wrong to think that UTF8 should be THE
standard? I believe it can encode anything
encoded by other encodings.
All the UTF-* encodings can encode the same code points. There are
different trade offs though.
Can't we consider non-utf8 text as legacy?
I don't like that word, but I do
Language of messages is quite different
from language of a file you read. (...)
Yes, it's a fundamental limitation of the
unix locale system and multi-user
systems. However it's no less wrong than
just picking UTF8 all the time. (...)
Am I wrong to think that UTF8 should be THE
standard?
On Nov 30, 2007 12:20 PM, Pablo Nogueira [EMAIL PROTECTED] wrote:
A question about existential quantification:
Given the existential type:
data Box = forall a. B a
[...]
I cannot type-check the function:
mapBox :: forall a b. (a - b) - Box - Box
--:: forall a b. (a - b) -
Stupid of me:
Isn't the code for mapBox :: forall a. (a - a) - Box - Box
encoding the proof:
Assume forall a. a - a
Assume exists a.a
unpack the existential, x :: a = T for some T
apply f to x, we get (f x) :: a
pack into existential, B (f x) :: exists a.a
Discharge first
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, the info and the news all on
the one page.
I
Hi
taken from ch.8.3 in the Hutton book:
Whereas return v always succeeds, the dual parser failure always
fails regardless of the contents of the input string:
The dual parser failure?
Cheers,
Paul
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A question about existential quantification:
Given the existential type:
data Box = forall a. B a
in other words:
-- data Box = B (exists a.a)
-- B :: (exists a.a) - Box
I cannot type-check the function:
mapBox :: forall a b. (a - b) - Box - Box
--:: forall a b. (a - b) -
mapBox :: forall a b. (a - b) - Box - Box
--:: forall a b. (a - b) - (exists a.a) - (exists a.a)
mapBox f (B x) = B (f x)
However, at first sight |f| is polymorphic so it could be applied to
any value, included the value hidden in |Box|.
f is not polymorphic here; mapBox
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
Sterling Clover wrote:
I'm still curious if the pre-calculation of partial sums that I did
works well across processors, as I don't see why it shouldn't. My
less-strictified version of Don's code is attached, and below are the
functions you'll need to insert/replace to make the partial-sums
Was this with tossing the partial sums code into the optimised bangs
program? Weird. I wonder if profiling will help explain why? In any case, If
nobody comes up with any other tweaks, I'll probably submit the optimised
bangs version to the shootout this weekend.
--S
On Nov 30, 2007 1:30 PM,
Rob Hoelz wrote:
Hello fellow Haskellers,
Does anyone know if/where I can find a specification for the .hi files
generated by GHC? I ask because I want to write an omni-completion
plugin for Vim to make Haskell hacking a bit nicer.
You don't want to do that.
The .hi files can expose
On Thu, 2007-11-29 at 07:29 +, Thomas Davie wrote:
On 29 Nov 2007, at 06:32, PR Stanley wrote:
Hi
Thanks for the response.
JCC: In most languages, if you have some expression E, and when the
computer attempts to evaluate E it goes in to an infinite loop, then
when the
On Nov 30, 2007 5:39 PM, Andrew Coppin [EMAIL PROTECTED] wrote:
Hmm. Secret... library... How do you guys find out about all this stuff?
There's
http://www.haskell.org/haskellwiki/Arrays#Unsafe_indexing.2C_freezing.2Fthawing.2C_running_over_array_elements
.
Cheers,
--
Felipe.
More elaboration ...
1) i checked HsUnixConfig.h and the macro HAVE_SYS_TIMES_H is set to 1
On Nov 30, 2007 8:28 PM, Galchin Vasili [EMAIL PROTECTED] wrote:
Hello,
0) All work being done on cygwin. Version 6.8.1 of ghc.
1) I ran runhaskell Setup.lhs configure and did a tail -f
On Nov 30, 2007 7:26 PM, Dan Weston [EMAIL PROTECTED] wrote:
There seems to be three salient benefits of using arrows, as I read the
Abstract and Introduction of Benjamin Lerner, Arrow Laws and Efficiency
in Yampa, 2003,
http://zoo.cs.yale.edu/classes/cs490/03-04a/benjamin.lerner/
1) The
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