2011/5/3 Manuel M T Chakravarty :
> Interestingly, today (at least the academic fraction of) the Haskell
> community appears to hold the purity of the language in higher
> regard than its laziness.
I find Greg Morissett's comment on Lennart Augustsson's article pro
lazy evaluation very interesting
For a historical perspective, I highly recommend The Definitive Account of the
History of Haskell:
http://research.microsoft.com/en-us/um/people/simonpj/papers/history-of-haskell/index.htm
Section 7 clearly and directly cites the desire to have pure I/O as the
motivation for adopting monads.
Tony Morris:
> Interesting how I have been authoring and subsequently using monads in
> scala for several years and it is strictness that gets in the way more
> than anything.
Just to make sure that I understand you correctly. You are saying that when
you use monads in Scala, then strictness mak
On 03/05/2011, at 1:25 PM, Richard O'Keefe wrote:
> In one of his blog posts, Robert Harper claims that the natural numbers
> are not definable in Haskell.
>
> SML datatype nat = ZERO | SUCC of nat
> Haskell data Nat = Zero | Succ Nat
>
> differ in that the SML version has strict constru
I did most of the Yi integration work done so far, but I have not had time to
work on it lately. Yi already is a library (for dyre) and is designed to work
with different front ends. The approach I took was to add a new "Pango
Control" front end based on the existing Pango front end.
I think
On 11-05-02 11:25 PM, Richard O'Keefe wrote:
Fair enough, but what about
data Nat = Zero | Succ !Nat
It works. I say, Harper forgot it.
___
Haskell-Cafe mailing list
Haskell-Cafe@haskell.org
http://www.haskell.org/mailman/listinfo/haskell-ca
In one of his blog posts, Robert Harper claims that the natural numbers
are not definable in Haskell.
SML datatype nat = ZERO | SUCC of nat
Haskell data Nat = Zero | Succ Nat
differ in that the SML version has strict constructors, and so only
finite instances of nat can be constructed, wherea
> I'm a bit skeptical of adding builders for different variable length
> encodings to the library, simply because there are so many
> possibilities. I think creating a binary-vle (for variable length
> encoding) package would be worthwhile. I have an implementation of the
> VLE used in protocol buf
On 11-05-02 05:31 PM, Huynh Huu Long wrote:
Big thanks, that works for me as well. Doesn't GHC check whether a
type is allowed (like CInt,...) or not (like Bool,...)?
No, it doesn't, since version 6.10.1:
http://www.haskell.org/ghc/docs/6.10.1/html/users_guide/ffi-ghc.html#glasgow-foreign-heade
On 02/05/11 17:54, Ketil Malde wrote:
> I'm following Harper's blog, Existential Type¹, which I find to be an
> enjoyable and entertainingly written tirade about the advantages of
> teaching functional programming - specifically ML - to students. Of
> course, he tends to be critical of Haskell, bu
I actually agree with you on that regard, I think the best thing you can get
from Yi is just the basic editing commands (the same you would get from
vim), such as visual/edit mode and whatnot
The best thing that Leksah can turn into (and something that
Haskell desperately needs) is a Haskell versi
On 03.05.2011 00:43, Antoine Latter wrote:
On Mon, May 2, 2011 at 3:01 PM, Alexey Khudyakov
wrote:
Hello everyone!
Haskell have nice automatically derivable Show type class. It's quite useful
for debugging with one exception. String representation of even moderately
large value is completely
Ozgur Akgun wrote:
> Hi Alexey,
>
> On 2 May 2011 21:01, Alexey Khudyakov wrote:
>
> > My question is there any tool for reformatting result of show so it could
> > be read by human beings?
> >
>
> http://hackage.haskell.org/package/pretty-show
>
> Just use ppShow, instead of show.
ppShow al
Big thanks, that works for me as well. Doesn't GHC check whether a
type is allowed (like CInt,...) or not (like Bool,...)?
2011/5/2 Gábor Lehel :
> It works if I replace the 'bool' return type of 'finished' with int
> and CInt on the C++ and Haskell side, respectively, and test for (/=
> 0).
Rogan Creswick schrieb:
> We *do* still have some trouble maintaining / enforcing the PVP in
> general, and there are a few things that it doesn't cover (I don't
> believe exception behavior is covered, for example, although I'd argue
> that throwing more exceptions than a previous version introdu
On Mon, May 2, 2011 at 3:01 PM, Alexey Khudyakov
wrote:
> Hello everyone!
>
> Haskell have nice automatically derivable Show type class. It's quite useful
> for debugging with one exception. String representation of even moderately
> large value is completely unreadable (example below).
>
> My que
It works if I replace the 'bool' return type of 'finished' with int
and CInt on the C++ and Haskell side, respectively, and test for (/=
0).
On Mon, May 2, 2011 at 9:35 PM, Huynh Huu Long
wrote:
> Hi,
> I tried to access C++ iterators from Haskell via the FFI. There are two
> example programs att
On 2 May 2011 22:01, Alexey Khudyakov wrote:
> Hello everyone!
>
> Haskell have nice automatically derivable Show type class. It's quite
> useful for debugging with one exception. String representation of even
> moderately large value is completely unreadable (example below).
>
> My question is t
Hi Alexey,
On 2 May 2011 21:01, Alexey Khudyakov wrote:
> My question is there any tool for reformatting result of show so it could
> be read by human beings?
>
http://hackage.haskell.org/package/pretty-show
Just use ppShow, instead of show.
Hope this helps,
Ozgur
Hello everyone!
Haskell have nice automatically derivable Show type class. It's quite
useful for debugging with one exception. String representation of even
moderately large value is completely unreadable (example below).
My question is there any tool for reformatting result of show so it
co
Hi,
I tried to access C++ iterators from Haskell via the FFI. There are two
example programs attached, in Haskell as well as in C++. Both utilise the
same iterator wrapper example.cpp, but when running the Haskell program it
prints an empty list, where it should print the contents of some vector.
It's good to hear. Thanks!
2011/5/2 Jason Dagit :
>
> This is fixed in the git repository for GLUT, but I didn't push the fix to
> hackage yet:
> https://github.com/haskell-opengl/GLUT/pull/1
> Sorry for the inconvenience!
> Jason
___
Haskell-Cafe mail
On Mon, May 2, 2011 at 6:29 AM, Artyom Kazak wrote:
> Hi Cafe!
>
> When I'm running examles from Gloss graphics library, all examples
> except gloss-hello are crashing with the following error: "GLUT:
> Warning in gloss-easy: GL error: gloss-easy: : hPutChar:
> invalid argument (character is not
Hi Mathew,
I was not the one working on Yi integration so far, but let me tell
you
what I think of the matter. Yi attempts to be a full blown editor,
while Leksah
needs Yi as a library for text editing with features typical of a
source code editor component.
What we have in Leksah is an abstract T
Ok thanks, that helped
On Mon, May 2, 2011 at 11:53 PM, Michael Snoyman wrote:
> Type:
>
>yesod init
>
> It will ask you some questions and then generate a bootstrap site.
>
> Michael
>
> On Mon, May 2, 2011 at 4:40 PM, Mathew de Detrich
> wrote:
> > Im not sure what you mean exactly by "run
Type:
yesod init
It will ask you some questions and then generate a bootstrap site.
Michael
On Mon, May 2, 2011 at 4:40 PM, Mathew de Detrich wrote:
> Im not sure what you mean exactly by "run the scaffolder", (just to be
> clear, I am not exactly sure what technically scaffolding is apart
Im not sure what you mean exactly by "run the scaffolder", (just to be
clear, I am not exactly sure what technically scaffolding is apart from it
being referenced once or twice in your documentation)
I assume you are talking about setting up the handlers for a specific route,
and then creating tha
My best advice is to just run the scaffolder. Any other examples I can
point you to (like the Haskellers source code) will contain a lot of
extra information that won't necessarily apply to your case.
Michael
On Mon, May 2, 2011 at 4:28 PM, Mathew de Detrich wrote:
> ..
> You tell me this no
..
You tell me this now ;)
I was actually wanting to look at scaffolding, but the section for it in the
Yesod book is not completed yet (http://www.yesodweb.com/book/scaffold)
Well that was like 4 hours wasted
Do you have a quick example of how scaffolding is done with mkYesodData and
mkYes
Hi Cafe!
When I'm running examles from Gloss graphics library, all examples
except gloss-hello are crashing with the following error: "GLUT:
Warning in gloss-easy: GL error: gloss-easy: : hPutChar:
invalid argument (character is not in the code page)". A window with
produced picture is showed for
On Mon, May 2, 2011 at 9:29 AM, Dominique Devriese
wrote:
> I agree with your analysis. Throughout his different articles, I think
> Harper partly has a point when he says that laziness brings certain
> disadvantages (like e.g. complex memory and CPU behaviour) to Haskell
> (although I disagree wi
Actually, there's a much simpler solution already implemented in the
scaffolded site: instead of using mkYesod, use mkYesodData and
mkYesodDispatch. mkYesod is really just a combination of the two. The
former defines your route datatype, and the latter creates the
YesodDispatch instance. This allow
Ok I have found the source issue, in my case it was an issue that ended up
turning into how the modules for my Webserver is organized, and that
compiler error (about an ambiguous type) occurred because my main webserver
datatype was not instantiated yet in that module (using where aproot).
In essen
2011/5/2 Ketil Malde :
> "There is a particular reason why monads had to arise in Haskell,
> though, which is to defeat the scourge of laziness."
>
> My own view is/was that monads were so successful in Haskell since it
> allowed writing flexible programs with imperative features, without
> sacr
On 02/05/11 13:10, John Sneer wrote:
Simply: I would like to have direct access into several places
in a very long list.
Maybe you could use a zipper. Or just maintain the list split into
chunks. So l' = [stuffBefore,hi,stuffAfter].
Or if you want to be able to use each element of hi as a kind
Re-CCing the list.
On 2 May 2011 11:33, John Sneer wrote:
> I took a look at
> http://cvs.haskell.org/Hugs/pages/libraries/base/Data-Sequence.html
> but it doesn't seem to be helpful - cannot insert sequence into the
> sequence, just
> modification of a single element is supported. Moreover, inde
Well, I have more or less similar solution, but its efficiency for
map/foldr etc. is quite low :-(
Nevertheless, probably no other solution.
BR and thanks
John
--
John Sneer
johnsn...@operamail.com
On Mon, 02 May 2011 08:32 -0300, "Felipe Almeida Lessa"
wrote:
> On Mon, May 2, 2011 at
On Mon, May 2, 2011 at 8:16 AM, Ivan Lazar Miljenovic
wrote:
> On 2 May 2011 11:10, John Sneer wrote:
>> Hello all,
>>
>> I have rather strange question. I wonder whether there is an obvious
>> solution or not in Haskell. I tried but without defining quite
>> ugly tree-like structures and incorp
Sorry to reply after so long time.
When you say "there is no proble", I understand it as:
Even if some libraries were compiled with gcc, they are still
linkable with object files generated with llvm.
So this remembered me a problem I met long ago with no answer.
I compiled ghc 7 with ghc 6 and g
On 2 May 2011 11:10, John Sneer wrote:
> Hello all,
>
> I have rather strange question. I wonder whether there is an obvious
> solution or not in Haskell. I tried but without defining quite
> ugly tree-like structures and incorporating IORefs it seems to me like
> impossible.
What you want seems
Hello all,
I have rather strange question. I wonder whether there is an obvious
solution or not in Haskell. I tried but without defining quite
ugly tree-like structures and incorporating IORefs it seems to me like
impossible.
Note: I use ASCII art to explain.
let l be a Haskell list
+-+-
On 2011-05-02 03:54, Ketil Malde wrote:
> "There is a particular reason why monads had to arise in Haskell,
>though, which is to defeat the scourge of laziness."
>
> I wonder if there are any other rationale for a statement like that?
He spends one paragraph dismissing the usefulness of ref
Yes, I'm following it too, and it seems to me that Harper just allows his
dislike for Haskell to take advantage of his judgement. Monads as a way to deal
with laziness are a very common misconception.
Отправлено с iPhone
May 2, 2011, в 11:54, Ketil Malde написал(а):
>
> I'm following Harper'
I'm following Harper's blog, Existential Type¹, which I find to be an
enjoyable and entertainingly written tirade about the advantages of
teaching functional programming - specifically ML - to students. Of
course, he tends to be critical of Haskell, but it's nice to get some
thought provoking opi
44 matches
Mail list logo
