method and some others that I do not remember now.
I would like to know if this is due to some general cause or if it is
library specific.
2009/2/6 Roel van Dijk vandijk.r...@gmail.com
On Fri, Feb 6, 2009 at 5:22 PM, Alberto G. Corona agocor...@gmail.com
wrote:
then Data.List.head
Hi John,
I've just been going through the HDBC-ODBC code wondering if I could
find the spot that needs changing so that Doubles work properly with
MS-Access.
Could you please tell me, if I understand this correctly?
The bindCol function does not actually look at the particular value
type,
Sometimes the StableName library gives different values for the samr
function: Sometines gives two alternate values. I checked it in ghc-6.10.1
under windows and in ghc-6.8.2 under Linux:
This is an example
Prelude
System.Mem.StableName.hashStableName.System.IO.Unsafe.unsafePerformIO $
Sorry, I forgot to forward it to the list:
-- Forwarded message --
From: Alberto G. Corona agocor...@gmail.com
Date: 2009/1/25
Subject: Re: [Haskell-cafe] Haskell Web Framework
To: Donnie Jones don...@darthik.com
hi,
I´m working in a web application rather than a web framework
Language Shootout: ATS is the new top gunslinger. Beats
C++http://shootout.alioth.debian.org/u64q/benchmark.php?test=alllang=all
http://www.reddit.com/r/programming/comments/72hmw/language_shootout_ats_is_the_new_top_gunslinger/
...Many people somehow think that ATS is fast because of its
...@worc.ox.ac.uk
On Mon, 2009-01-19 at 01:36 +0100, Alberto G. Corona wrote:
The problem with Windows can be solved once and for all when CygWIN
will be considered for Windows instead of MinGW. Is that possible?
The standard Windows build of GHC does not use Cygwin. So all the
programs built with GHC
C:\Documents and Settings\Administratorcabal install plugins
Resolving dependencies...
cabal: dependencies conflict: ghc-6.10.1 requires Cabal ==1.6.0.1 however
Cabal-1.6.0.1 was excluded because plugins-1.3.1 requires Cabal ==1.4.*
2009/1/19 Alberto G. Corona agocor...@gmail.com
I finally
Do really pluigins needs Cabal (=1.4 1.5) ???
C:\Documents and Settings\Administratorcabal install plugins
Resolving dependencies...
cabal: dependencies conflict: ghc-6.10.1 requires Cabal ==1.6.0.1 however
Cabal-1.6.0.1 was excluded because plugins-1.3.1 requires Cabal ==1.4.*
This is one of the shortcomings of haskell not to mention other programming
languages. Mathemathicist would find it very annoying.
Instead of
instance Monoid Integer where
mappend = (+)
mempty = 0
instance Monoid Integer where
mappend = (*)
mempty = 1
which is not legal and the
Hi guys:
I don´t know how difficult really is, but it seens that it could be done
because all the necessary elements are there (except perhaps the mapping
package name-hackage url): Why hasn´t been done yet Is unknown to me.
It would be very useful and a big save of time to have a cabal commad
The question of imperative versus pure declarative coding has brought to my
mind some may be off-topic speculations. (so please don´t read it if you
have no time to waste): I´m interested in the misterious relation bentween
mathematics, algoritms and reality (see
As a physicist, I think that programming, like any design in general, is all
about making as little use of brain resources as possible at the time of
solving problems and to transmit the solution to others. This is the reason
why it is pervasive in all kinds of engineering the concepts of
The main addition of this versión is the capablity to safely
handle transact, and serialize to permanent storage many datatypes
simultaneously in the same piece of code and incrementally.
Just register each new datatype (with registerType :: Type). So it is not
necessary to glue all types in
Thanks Alistair,
inspiration had stuck me meanwhile and that's exactly what I did.
Günther
Bayley, Alistair schrieb:
From: haskell-cafe-boun...@haskell.org
[mailto:haskell-cafe-boun...@haskell.org] On Behalf Of Günther Schmidt
what does it take to install Takusen on Win32 with Sqlite
John Goerzen schrieb:
Günther Schmidt wrote:
Hi,
I am not yet 100% certain that the unsafe calls are indeed the cause of
the problem, eventhough I strongly suspect there are.
I can tell you more once I have managed to rewrite all unsafe calls into
safe once, reinstall HDBC.Sqlite3 and
Hi Duncan,
are you saying then that the db-code is what's blocking the UI?
Günther
Duncan Coutts schrieb:
On Mon, 2008-12-22 at 22:55 +0100, Günther Schmidt wrote:
Hi,
I put in on hpaste:
http://hpaste.org/13264
slightly simplified
Ok, that works fine when the action is
-- Forwarded message --
From: Alberto G. Corona agocor...@gmail.com
Date: 2008/12/19
Subject: Re: Fwd: [Haskell-cafe] Haskell as a religion
To: Dan Piponi dpip...@gmail.com
As far as I know, const only protect from updates that the compiler can
detect at compilation time
But many features need other features. For example, the option to use
referential transparency will be common in future languages for multicore
programming purposes. This creates the problem of separating
side-effect-free code from side-effect code. For this purpose, a strong type
system at
I have problems compiling plugins 1.3.1 in windows at the configure phase
configure: error C compiler cannot create executables
I use ghc 6.8.2
I know that plugins is nor much tested under windows but I´m trying anyway.
I think that this problem is very common also in Linux.
I tried to find
of the executable. I suppose that
this is because the ghc library.
2008/12/9 Alberto G. Corona agocor...@gmail.com
The duplicate definition error appears when I compile Main.hs and execute
it. But when I run it with runghc the behaviour is different. It works
well:
runghc Main.hs
3
Any idea
The duplicate definition error appears when I compile Main.hs and execute
it. But when I run it with runghc the behaviour is different. It works
well:
runghc Main.hs
3
Any idea? is this a bug of hs-plugins? it is just something expected??
2008/12/6 Alberto G. Corona [EMAIL PROTECTED]
I have
I have a web server which load server extensions. these extensions eval-uate
configuration files that contains code (user-editable workflow
descriptions). The problem is that I need common definitions for the
extensions and for the configurration files. This is not permitted by
ha-plugins.
The
this to haskell-cafe again.
Alberto G. Corona wrote:
Not so much memory, because data is referentially transparent, the new Map
can point to whole subtrees of the old map that stay the same. is similar
than when a new list is created by prefixing a new element from a old
list
ys= x:xs. ys
sorry, Dons,
-- Forwarded message --
From: Alberto G. Corona [EMAIL PROTECTED]
Date: 2008/11/18
Subject: Re: [Haskell-cafe] implementing python-style dictionary in Haskell
To: Don Stewart [EMAIL PROTECTED]
By the way byteStrings are wonderful, but, it isn´t true
Is there any abstract container that permits the addition of new types of
data? I know how to simulate the extension of Algebraic datatypes, but this
does not permit the addition of data with new types in the same container
and recover them in a type-safe way.
Did I reinvent the Weel? I found
of type
(a- m a) usually m=IO
f x =\x'- g x' = \x''-... z
by prefixing the user with the method step:
step f x = \x'- step g x' = \x''-...
This means that a workflow can be described with the familiar do notation.
In principle, there is no other limitation on the syntax but the restriction
(a - m
A performance improvement could be the caching of responses based on
computation costs and number of accesses. This functionality can be
implemented a general module that may be used to wrap any pure program if
needed. This is something that only pure programs can ever do. And the
haskell type
I forgot to cc to haskell-cafe:
-- Forwarded message --
From: Alberto G. Corona [EMAIL PROTECTED]
Date: 2008/11/2
Subject: Re: [Haskell-cafe] Re: [Haskell] ANNOUNCE: RefSerialize-0.2.1
To: Bulat Ziganshin [EMAIL PROTECTED]
* SerTH is a binary serialization library for Haskell
actualized to 0.2.3 due to some errors in the cabal description. Sorry,
some needed module was not exported.
2008/11/2 Alberto G. Corona [EMAIL PROTECTED]
I uploadad
RefSerializehttp://hackage.haskell.org/cgi-bin/hackage-scripts/package/RefSerialize
to Hackage .
Read, Show
I need to backup my ubuntu-VMWare image frequently (5 GBits) . I need to
know if exist such a utility (in haskell or not) for single file
syncronization.
I don´t want to reinvent te weel, but I think that it is a few lines of
Haskell using the Diff package or something similar.
I uploadad
RefSerializehttp://hackage.haskell.org/cgi-bin/hackage-scripts/package/RefSerialize
to Hackage .
Read, Show and Data.Binary do not check for repeated references to the same
data address. As a result, the data is serialized multiple times when
serialized. This is a waste of space in
Is there a way to know the number of memory references for a variable?. The
runtime must know it but i do not know if this available for the program
trough any low level trick
Thanks
___
Haskell-Cafe mailing list
Haskell-Cafe@haskell.org
-- Forwarded message --
From: Alberto G. Corona [EMAIL PROTECTED]
Date: 2008/10/29
Subject: Re: [Haskell-cafe] ANNOUNCE: Data.TCache 0.5.1
To: Joachim Breitner [EMAIL PROTECTED]
I developed it in 2006. At this time I think that Happs did not used STM. I
do not know Happs.State
I uploaded TCache to hackage.org.
Data.Tcache is a transactional cache with configurable persistence. It tries
to simulate Hibernate for Java or Rails for Ruby. The main difference is
that transactions are done in memory trough STM. There are transactional
cache implementations for some J2EE
with:
{-# OPTIONS -fglasgow-exts -fallow-undecidable-instances #-}
class A a
class R a
class S a
instance R a = A a
instance S a = A a
--
GHC gives
*Duplicate instance declarations*
* instance R a = A a *
* instance S a = A a *
**
*Why?*
-time) instantiate a new class as Num and how to test the axioms for
the new class.
All of then is something like a sophisticated assert mechanism, but , I
think, much more flexible and elegant.
2008/10/22 Alberto G. Corona [EMAIL PROTECTED]
I guess that the namespace thing is not necesary. Maybe
Also in my weblog:
http://haskell-web.blogspot.com/2008/10/axioms-properties-for-haskell-classes.html
2008/10/23 Alberto G. Corona [EMAIL PROTECTED]
It seems that some of the goals are not so hard. here I publised my
progress.
http://docs.google.com/Doc?id=dd5rm7qq_165rshp74gfpli=1
I show
I´m just thinking aloud, but, because incorporating deeper mathematics
concepts has proven to be the best solution for better and more flexible
programming languages with fewer errors, I wonder if raising the type
classes incorporating axioms can solve additional problems.
At first sight it does:
Personally, I'm loving the whole concept of this puppy:
GHC.Prim.*reallyUnsafePtrEquality#
I have absolutely no idea what it does, but it must be something really
unsafe! ;-)i
I really need reallyUnsafePtrEquality# ! . I need it in inside
GHC.Exts if GHC.Prim is being removed. Please!..
Hello
I've been doing some stuff with existential data types and came across a
curious pattern. If anyone has thoughts, comments, or feedback, it
would be appreciated.
---
I'm trying to port and extend the Be messaging scheme to Haskell for use
in distributed, heterogenous environments.
By the way, Ihave developped the coreof asearch engine completely in Haskell.
It can index arbitrary objects (including files, of course)
has definitions for filters, with predefined filters for plain text, HTML/XML and ageneral filter for Haskell data types
It has basic search capabilities: it
Hi,
I have a program that handle cached data. I don´t find the way to store
the data when the program is killed by other program. There is nothing
similar to signal in the Windows implementation and no exception
appears to trigger when the program is killed by a service handler or
by the Task
To: Alberto G. Corona [EMAIL PROTECTED]
Cc: haskell-cafe@haskell.org
Message-ID:
[EMAIL PROTECTED]
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
On 5/13/06, Alberto G. Corona [EMAIL PROTECTED] wrote:
notglobal = newIORef True
main = do a - notglobal
b - notglobal
Thanks
]
Content-Type: text/plain; charset=us-ascii
Alberto G. Corona [EMAIL PROTECTED] writes:
stmcache= newTVar 0
I will explain what this doesn't with an analogy.
import Data.IORef
notglobal = newIORef True
main = do a - notglobal
b - notglobal
writeIORef a False
x
Hi,
I´m trying to make a searchable transactional cache using STM. The
whole idea is to use indexed TVar variables using a FiniteMap. another
TVar holds the finitemap . This last TVar has to be a global variable.
I found that when handled as global, a TVar does not keep the state.
For example:
Title: RE: [Haskell-cafe] Type classes
I suppose you want to define compareEntries like this:
compareEntries (Entry x) (Entry y) = compareEntries x y
An option is to just implement it the following way (Haskell98!):
class DatabaseEntry e where
entryLabel :: e - String
formatEntry :: e
Title: RE: [Haskell-cafe] how would this be done? type classes? existentialtypes?
Try using a GADT:
data Rs where
Rs :: Resource a = a - Rs
class Resource a where
resourceName :: a - String
instance Resource String where
resourceName x = String
instance Resource Int where
Lennart Augustsson wrote (on Sat, 14 May 2005 at 16:01):
Why would a constructivist think that all functions are continuous?
It makes no sense.
How would you define a non-continuous function (on reals, say)
without (something like) definition by undecidable cases?
Formal systems
Greg Buchholz wrote (on Wed, 09 Mar 2005 at 20:08):
Can anyone recommend a nice dependently typed language to play with?
Cayenne, Epigram, other?
http://www.cs.chalmers.se/~catarina/agda/
See also the sexy IDE alfa: http://www.cs.chalmers.se/~hallgren/Alfa/
Peter Hancock
before I get
your mail.
Mark Carroll wrote:
On Thu, 3 Mar 2005, Sam G. wrote:
I need a Monad to represent an internal stack. I mean I've got a lot
of functions which operates on lists and I would not like to pass the
list as an argument everytime.
Could you help me writing this monad? To start
I need a Monad to represent an internal stack. I mean I've got a lot of
functions which operates on lists and I would not like to pass the list as an
argument everytime.
Could you help me writing this monad? To start, I just need a + function which
will return the sum of the 2 toppest elements
Lennart Augustsson wrote (on Mon, 14 Feb 2005 at 14:55):
Any definition can be made point free if you have a
complete combinator base at your disposal, e.g., S and K.
Haskell has K (called const), but lacks S. S could be
defined as
spread f g x = f x (g x
Ben Rudiak-Gould wrote (on Tue, 25 Jan 2005 at 14:49):
Mark Carroll wrote:
Wasn't there someone mentioning here a little while ago
some project where they strip most of System.* from the libraries and get
something that might be suitable for embedded applications? What was
Jon Cast wrote (on Tue, 14 Dec 2004 at 22:02):
No. All that is needed for ($) to work is impredicativity (or, more
precisely, for the foralls in ($)'s type to be impredicative). That is
something that could easily be implemented in a compiler. I'm not clear
on why it
At the moment I'm only thinking of parameter-less kind declarations but
one could easily imagine kind parameters, and soon we'll have kind
polymorphism but one step at a time.
Any thoughts?
Apologies if it's widely known, but a system with kind polymorphism
was first considered by
Sound on linux tends to center around the jack sound
architecture. This is a demon for connecting audio and midi gadgets
as it were by jack-leads. From a brief look, it seems very callback
oriented. It seems to be highly thought of by knowledgable audio
types, and the bee's knees for low
Samuel E Moelius, wrote (on Wed, 06 Aug 2003 at 15:35):
On Wednesday, August 6, 2003, at 06:15 AM, C T McBride wrote:
This is why most sensible dependent type theories have a hierarchy of
universes behind the scenes. You can think of * in Haskell as the lowest
universe,
Hello,
How can I make an explicit function call in a do sequence?
Ex:
... do let a = myFunc ...
b = myFunc ...
c = Something else
return c
...
As I understand myFunc will not be executed, but I need it...
Please, help.
--
Pavel Zhbanov
Hello,
Is it even possible to make a global variable in Haskell?
If yes, how?
Thanks.
--
Zhbanov Pavel
___
Haskell-Cafe mailing list
[EMAIL PROTECTED]
http://www.haskell.org/mailman/listinfo/haskell-cafe
I am new to haskell.
I am trying to do some excersise but i can't make anything work :(
This is my code.I replaced spaces with underscores ( _ )
Thanks for any suggestions or correctrions
import IO
import System
import List
import Maybe
import Char
import Numeric
type Name=String
type Room=Int
_|_(c=='a'||_c=='b'||_c=='c'||_c=='d'||_c=='e'||_c=='f'
||_c=='g'||_c=='h'||_c=='i'||__c=='j'||_c=='k'||_c=='l'||_c=='m'||_c=='n'
||_c=='o'||_c=='p'||_c=='q'||_c=='r'||_c=='s'||_c=='t'||_c=='u'||_c=='v'
||_c=='w'||_c=='x'||_c=='y'||_c=='z'||c=='A'||_c=='B'||_c=='C'||_c=='D'
||_c=='E'||_c=='F
Andy Moran wrote (on Fri, 26 Jul 2002 at 16:52):
As for removing vowels, instead of proposing a solution, I choose to dispute
that the problem needs solving and claim victory.
Removing vowels from identifiers can be very important if
you are writing in certain assemblers from the
lmichele wrote (on Sun, 30 Jun 2002 at 09:26):
By the way, what's the purpose of this coding? (this is the type of
question: ok, I have a hammer, now, for what kind of nail it is useful?)
I would guess that something like the asked-for counter could be
useful if one is allocating
Apropos of section notation, don't forget flip, alias the C
combinator. It allows you to express partial applications to the next
argument but one is in operator section notation.
We can express (usually horribly) any affine lambda-abstraction with
flip, (.), id and const.
Peter Hancock
301 - 364 of 364 matches
Mail list logo
