On Wed, Mar 10, 2010 at 8:07 AM, Warren Henning
warren.henn...@gmail.com wrote:
Wow. Quite ambitious.
Was this inspired by work at your current employer like with Atom and
some of the other stuff you've released?
Yes, we had an immediate need to debug some machine code. I looked
around, but
Hi Oleg,
(cc'ed the haskell-cafe as it may be of interest to other readers)
On Tue, 9 Mar 2010 o...@okmij.org wrote:
Hi, Bruno!
Of course I know the EMGM paper and approach -- we discuss it
at great length in the paper we are both editing, don't we? What I had
in mind about tagless
Hi All,
A few days ago, I got started with the code found on this blogpost:
http://www.serpentine.com/blog/2008/09/30/unix-hacking-in-haskell-better-pseudoterminal-support
On my system, I found that using pseudoterminals as handles did not work.
Reading output and writing input works fine, it's
Martijn van Steenbergen wrote:
Tom Schrijvers wrote:
data EvalDict sem = EvalDict { val :: Int - sem Int, add :: sem Int
- sem Int - sem Int }
An alternative option is to capture the structure in a GADT:
data Eval a where
Val :: Int - Eval Int
Add :: Eval Int - Eval Int - Eval Int
And
On Mar 10, 2010, at 8:47 AM, Ketil Malde wrote:
I think it is better style to avoid this kind of one-off named
values. I much prefer:
then Golds ++show (gold s g)++...
For some reason, this is a style isse that doesn't get much attention
At the end of the Section on function
Maybe it's just me, but I think composition chain is MUCH easier to read.
When readning, I'd probably transform the last version to the previous one by
hand, just to make it more comprehensible.
Sebastian Fischer wrote:
On Mar 10, 2010, at 8:47 AM, Ketil Malde wrote:
I think it is better
This something you are afaik able to do.
I'm cc'ing David (qthaskell's author).
On Wed, Mar 10, 2010 at 1:59 AM, Philip Beadling
phil.beadl...@googlemail.com wrote:
Hi,
I know this isn't a qtHaskell list, but I don't think there is one.
Was wondering if anyone has any ideas on the below.
From: Ketil Malde ke...@malde.org
S. Doaitse Swierstra doai...@cs.uu.nl writes:
then (s1 ++ s2 ++ s3 ++ s4) where
s1 = Golds
s2 = show (gold s g)
s3 = , Silvers
s4 = show (silver s g)
If you want to keep the definitions local to
Yitzchak Gale schrieb:
Henning Thielemann wrote:
Is NumLazyByteString a newtype around Bytestring.Lazy
that interprets the bit stream represented by the ByteString
as integer?
Thomas DuBuisson wrote:
Not exactly. There is not newtype wrapper. NumLazyByteString is:
instance Num
From: zaxis z_a...@163.com
So if the local variable can be changed, then we can use loop, etc. same as
imperative languages. For example, for (i=0; i100; i++) where `i` is a
local variable in function.
In addition to John Millikin's suggestion, you can also do:
map f [0..99]
where f ::
Miguel Mitrofanov miguelim...@yandex.ru writes:
Maybe it's just me, but I think composition chain is MUCH easier to read.
I definitely agree.
[Cited from Learn You a Haskell for Great Good]
oddSquareSum :: Integer
oddSquareSum = sum . takeWhile (1) . filter odd . map (^2) $
On 10 March 2010 11:21, Ketil Malde ke...@malde.org wrote:
[Cited from Learn You a Haskell for Great Good]
oddSquareSum :: Integer
oddSquareSum = sum . takeWhile (1) . filter odd . map (^2) $ [1..]
To me, the first one is very clear, and exposes the function as what it
is: a
Colin Adams colinpaulad...@googlemail.com writes:
Named values are just like comments, which IMO also should be kept to a
bare minimum. A bit tongue in cheek: If you need a name to understand
what a function does, or a comment to understand how it does it, then
your code is too complicated.
I like to detect at runtime whether the processor my program runs on has
certain extensions (SSE2, SSE3 or so) in order to execute optimized
code. On Linux I can process the contents of /proc/cpuinfo but this will
not work on Windows. Is there a portable way in Haskell?
On Mar 10, 2010, at 12:21 PM, Ketil Malde wrote:
Introducing names means that I need to keep the temporary
definitions in my
head, and I think takeWhile (1) is as clear as it can get. And
while a name can be misleading (belowLimit is a boolean, no?) or flat
out wrong, the definition has
If you use intel processor, you should call 'cpuid' assembler
instruction to obtain this info.
Look at this document for the instruction semantics:
http://www.intel.com/Assets/PDF/manual/253666.pdf
There is a wrapper for cpuid in haskell:
http://hackage.haskell.org/package/cpuid
Henning
Am Mittwoch 10 März 2010 13:03:59 schrieb Ketil Malde:
never introduce names if it increases the
size of your program. (Corrolary: don't name things that aren't
referred to at least twice)
Objection!
If the final result of your function is a combination of a handful or two
of long (and
Hello all
Algorithmically oddSquareSum is a bit below par though...
oddSquareSum :: Integer
oddSquareSum = sum . takeWhile (1) . filter odd . map (^2) $ [1..]
Why filter out the evens after generating them?
oos1 :: Integer
oss1 = sum . takeWhile (1) $ map (^2) odds
where odds
On Wed, Mar 10, 2010 at 3:53 PM, Stephen Tetley
stephen.tet...@gmail.com wrote:
where odds = iterate (+2) 1
Or odds = [1,3..]
--Max
___
Haskell-Cafe mailing list
Haskell-Cafe@haskell.org
http://www.haskell.org/mailman/listinfo/haskell-cafe
Hi Max
Nice! - I didn't know about that syntax.
PS I should have said
Why generate the evens only to filter them out?
On 10 March 2010 13:57, Max Rabkin max.rab...@gmail.com wrote:
[Snip]
Or odds = [1,3..]
___
Haskell-Cafe mailing list
Sebastian Fischer s...@informatik.uni-kiel.de writes:
I do not agree that introducing names locally for compositions is
*always* a bad idea, even if used only once.
Well, of course I do that all the time too. :-)
(Choosing names that are misleading or flat out wrong is of course
always a
Am Mittwoch 10 März 2010 14:53:32 schrieb Stephen Tetley:
Hello all
Algorithmically oddSquareSum is a bit below par though...
oddSquareSum :: Integer
oddSquareSum = sum . takeWhile (1) . filter odd . map (^2) $
[1..]
Why filter out the evens after generating them?
oos1 ::
Stephen Tetley stephen.tet...@gmail.com writes:
oddSquareSum :: Integer
oddSquareSum = sum . takeWhile (1) . filter odd . map (^2) $ [1..]
Why filter out the evens after generating them?
In other words:
sum . takeWhile (1) . filter odd . map (^2) $ [1..]
Since odd (x^2) = odd x:
I've got N900 recently and saw that according to this page
http://hackage.haskell.org/trac/ghc/wiki/Platforms
it's not possible to run GHC and GHCi easily on ARM. This sucks.
I want to propose a project bring GHC back to life on arm-linux. It is
supposed that the outcome will be a package for
Good names can help making comments less important.
OTOH, comment can give you the best(?) of both worlds, both revealing
the linear structure of the function, while still providing extra
information:
oddSquareSum :: Integer
oddSquareSum = sum -- add together
On Wed, 10 Mar 2010 17:43:06 -0500
Yakov == Yakov Zaytsev ya...@yakov.cc wrote:
Yakov I want to propose a project bring GHC back to life on
Yakov arm-linux. It is supposed that the outcome will be a package
Yakov for Maemo 5.
I hope we'll have MeeGo by the end of GSOC. ;)
Go, for it!
On Sun, 7 Mar 2010 21:03:12 -0800
Michael == Michael Snoyman mich...@snoyman.com wrote:
Michael * Deployable anywhere (based on WAI)
Does it mean one will be able to use it with webservers like Cherokee,
nginx...?
Sincerely,
Gour
--
Gour | Hlapicina, Croatia | GPG key: F96FF5F6
On Wed, 2010-03-10 at 13:03 +0100, Ketil Malde wrote:
Colin Adams colinpaulad...@googlemail.com writes:
Named values are just like comments, which IMO also should be kept to a
bare minimum. A bit tongue in cheek: If you need a name to understand
what a function does, or a comment to
On Wed, Mar 10, 2010 at 7:10 AM, Gour g...@gour-nitai.com wrote:
On Sun, 7 Mar 2010 21:03:12 -0800
Michael == Michael Snoyman mich...@snoyman.com wrote:
Michael * Deployable anywhere (based on WAI)
Does it mean one will be able to use it with webservers like Cherokee,
nginx...?
Right
On Wed, 10 Mar 2010 07:24:15 -0800
Michael == Michael Snoyman mich...@snoyman.com wrote:
Michael Right now, the only WAI backends I'm aware of are the two I've
Michael written: SimpleServer and CGI. Assuming Cherokee and nginx
Michael support CGI, then yes, you could deploy there.
I'm more
So if the local variable can be changed, then we can use loop,
etc. same as imperative languages. For example, for (i=0; i100; i++)
where `i` is a local variable in function.
It is true that a pure language could support such things (some pure
languages do, e.g. Sisal). The experience of
Here's a transcript from a conversation I had with Conal on IRC.
tl;dr: conal cross-module inlining is only possible because ghc
stashes a definition in a .hi, iuuc. i'm suggesting that the stashed
definition either (a) never include further inlinings, or (b) be
augmented by such a definition.
This is my understanding:
Old story (GHC 6.12.1 (?) and below):
1) Function bodies are only optimised if they are not marked INLINE.
The assumption is that INLINE bodies will be inlined and then
optimised at the point where they are inlined.
2) Unfoldings are exported in .hi files for functions
Hi:
I am running GHC 6.10.4 on Mac OSX 10.6.2. Somehow, I have a broken version
of Cabal (1.6.0.3) installed. In order to fix it, I thought I should just
upgrade to the Haskell Platform. Is it necessary to uninstall my current GHC
first? If, so, how?
Thanks you.
Cheers,
David
Ketil Malde wrote:
Also, good names are harder than they sound: I don't think
'belowLimit' is a good name for 'takeWhile (1)', for instance.
I certainly couldn't guess what it was for without looking at the
implementation, which kind of defeats the purpose of names for
improving code
What's the status on this? Have we applied as organization? Do we have
enough mentors?
Cheers,
Johan
On Mon, Feb 1, 2010 at 4:02 PM, Edward Kmett ekm...@gmail.com wrote:
I would happily participate as a mentor again and I am willing to step up
as administrator if you want to get it off your
On Wed, Mar 10, 2010 at 8:00 AM, Gour g...@gour-nitai.com wrote:
[...]
Michael That said, I intend to port hack-handler-fastcgi to WAI in the
Michael not-too-distant future. If anyone needs it sooner, just send
Michael me an e-mail, it will probably take very little time to port
Michael
On Wed, 10 Mar 2010 09:18:02 -0800
Michael == Michael Snoyman mich...@snoyman.com wrote:
Michael During the planning of WAI, they mentioned that Happstack
Michael uses the sendfile system call for optimizing sending of
Michael static files. WAI includes support for this now (look at the
Michael
Tom Schrijvers wrote:
William Cook's Onward! essay is relevant here. He characterizes the
difference between objects and abstract data types nicely: the latter
allow binary methods that pattern match (to exploit the combined
knowledge of the internals of two different values) whereas objects
On Wed, Mar 10, 2010 at 10:11 AM, Gour g...@gour-nitai.com wrote:
[..]
Michael I also wouldn't have a use for mod_haskell, but it seems
Michael every cool kid on the block has it ;).
How do you like other players (Cherokee, nginx,...)?
Frankly, I haven't used either of those (though I
I think I've reached the point where I need some tutoring, so provided
I've got money for travel and course fees, and time, where do I get it? I'm
not a student so some courses aren't available to me.
How about visiting our Haskell meeting in Leipzig, June 4th?
Which I can only recommend!
Hello,
I am learning haskell and I found a space leak that I find difficult to
solve. I've been asking at #haskell but we could not solve
the issue.
I want to lazily read a set of 22 files of about 200MB each, filter them and
then I want to output the result into a unique file.
If I modify the
Hello Arnoldo,
Wednesday, March 10, 2010, 11:45:56 PM, you wrote:
I am learning haskell and I found a space leak that I find
difficult to solve. I've been asking at #haskell but we could not solve
the issue.
make some experiments - leave only one file and use version A, then
replace
After programming as an exercice the sum function, my version is
faster than the Data.List's version. Looking at the source code,
Data.List uses a foldl and not a foldl'. foldl' seems faster and
allows to use very big lists. So, why is foldl used by Data.List for
sum?
--
Guillaume Pinot
Am Mittwoch 10 März 2010 21:45:56 schrieb Arnoldo Muller:
Hello,
I am learning haskell and I found a space leak that I find difficult to
solve. I've been asking at #haskell but we could not solve
the issue.
I want to lazily read a set of 22 files of about 200MB each, filter them
and then I
texitoi:
After programming as an exercice the sum function, my version is
faster than the Data.List's version. Looking at the source code,
Data.List uses a foldl and not a foldl'. foldl' seems faster and
allows to use very big lists. So, why is foldl used by Data.List for
sum?
It's
Am Mittwoch 10 März 2010 22:33:43 schrieb TeXitoi:
After programming as an exercice the sum function, my version is
faster than the Data.List's version. Looking at the source code,
Data.List uses a foldl and not a foldl'. foldl' seems faster and
allows to use very big lists. So, why is foldl
Hello Daniel:
Thanks!
I employed mapM'_ but I am still getting the space leak.
Any other hint?
Arnoldo
On Wed, Mar 10, 2010 at 10:40 PM, Daniel Fischer
daniel.is.fisc...@web.dewrote:
Am Mittwoch 10 März 2010 21:45:56 schrieb Arnoldo Muller:
Hello,
I am learning haskell and I found a
Hello Bulat,
I ran program A with writeFile instead of appendFile and it still works
without problems.
Regarding program B, if I use writeFile the leaking still occurs.
Any other hints? :)
Arnoldo
On Wed, Mar 10, 2010 at 10:32 PM, Bulat Ziganshin bulat.zigans...@gmail.com
wrote:
Hello
Hello Justin,
I tried and what I saw was a constant increase in memory usage.
Any particular profiling option that you would use?
I do remember that there was a particular option in which the leak would
dissapear (for the same amount of work) and that is why I stopped using the
profiler.
Hi:
I have just installed the Haskell Platform 2009.2.0.2 on Mac OSX 10.6.2. When
I try to install wx I get the following error which I do not understand.
Can anyone give me a hint?
$ cabal install wx
Resolving dependencies...
cabal: cannot configure containers-0.3.0.0. It requires base =4.2
Hello Arnoldo,
Wednesday, March 10, 2010, 11:45:56 PM, you wrote:
I am learning haskell and I found a space leak that I find
difficult to solve. I've been asking at #haskell but we could not solve
the issue.
what if you use program B on single file?
--
Best regards,
Bulat
Bulat,
The same happens, the memory starts to quickly fill up...
Arnoldo
On Wed, Mar 10, 2010 at 11:16 PM, Bulat Ziganshin bulat.zigans...@gmail.com
wrote:
Hello Arnoldo,
Wednesday, March 10, 2010, 11:45:56 PM, you wrote:
I am learning haskell and I found a space leak that I find
On 11 March 2010 09:14, David Place d...@vidplace.com wrote:
$ cabal install wx
Resolving dependencies...
cabal: cannot configure containers-0.3.0.0. It requires base =4.2 6
For the dependency on base =4.2 6 there are these packages: base-4.2.0.0.
However none of them are available.
Daniel Fischer daniel.is.fisc...@web.de writes:
Am Mittwoch 10 März 2010 22:33:43 schrieb TeXitoi:
After programming as an exercice the sum function, my version is
faster than the Data.List's version. Looking at the source code,
Data.List uses a foldl and not a foldl'. foldl' seems faster
Am Mittwoch 10 März 2010 23:01:28 schrieb Arnoldo Muller:
Hello Daniel:
Thanks!
I employed mapM'_ but I am still getting the space leak.
Any other hint?
Hmm, offhand, I don't see why that isn't strict enough.
With some datafiles, I could try to investigate.
One question, how does programme
Wolfgang Jeltsch wrote:
Hello,
some time ago, it was pointed out that generalized newtype deriving could be
used to circumvent module borders. Now, I found out that generalized newtype
deriving can even be used to define functions that would be impossible to define
otherwise. To me, this is
Hi Max. Thanks much for passing on this info. Very encouraging news! -
Conal
On Wed, Mar 10, 2010 at 8:41 AM, Max Bolingbroke batterseapo...@hotmail.com
wrote:
This is my understanding:
Old story (GHC 6.12.1 (?) and below):
1) Function bodies are only optimised if they are not marked
Am Mittwoch 10 März 2010 23:31:15 schrieb Ivan Miljenovic:
On 11 March 2010 09:14, David Place d...@vidplace.com wrote:
$ cabal install wx
Resolving dependencies...
cabal: cannot configure containers-0.3.0.0. It requires base =4.2
6 For the dependency on base =4.2 6 there are these
On Mar 10, 2010, at 6:33 PM, Daniel Fischer wrote:
cabal install wx-0.12.1.2 wxcore-0.12.1.2 wxdirect-0.12.1.1
has good chances to work on 6.10.*
Indeed, it just finished compiling. Thank you.
___
Haskell-Cafe mailing list
Hi John,
Doing a Google search for haskell parser returns the following link as its
first result. That's the parser that GHC uses.
http://www.haskell.org/happy/
You could also check out the following:
http://www.haskell.org/haskellwiki/Parsec
How about visiting our Haskell meeting in Leipzig, June 4th?
Which I can only recommend! It has been nice last year.
Thanks! We're in still in the planning stages for this year
(the date and city are set, but the actual location is not).
Anyway if you have a suggestion for a tutorial or a
Hello,
I'm pleased to announce the first release of Bravo, a static text
template generation library, on Hackage:
http://hackage.haskell.org/package/Bravo.
Bravo is a text template library that provides parsing and generation of
templates at compile time. Templates can be read from strings
63 matches
Mail list logo
