[Haskell-cafe] Bidirectional programming in Haskell

Hi, On Tue May 26 01:21:28 EDT 2009, Artyom Shalkhakov wrote: > Are there any libraries for "bidirectional" [1] programming > in Haskell? Any related work? Some of the early work in the PSD project (closely related to the "lenses") were developed in Haskell, http://www.iis.sinica.edu.tw/~scm/

Re: [Haskell-cafe] Anglohaskell?

Sounds fun! I have no time to organise it, but someone should. It really isn't that hard! Thanks Neil On Mon, May 25, 2009 at 4:47 PM, Philippa Cowderoy wrote: > Is anyone up for Anglohaskell this year? > > Perhaps more importantly, is anyone willing to step forward to run it? I > can lend a ha

[Haskell-cafe] ANNOUNCE: Haskell Communities and Activities Report (16th ed., May 2009)

On behalf of the many, many contributors, I am pleased to announce that the Haskell Communities and Activities Report (16th edition, May 2009) http://www.haskell.org/communities/ is now available from the Haskell Communities home page in PDF and HTM

[Haskell-cafe] Re: ANN: New repository and trac for haskell-src-exts

Hi Niklas, Do you want people to cc bugs they want to "vote" for - like the GHC people do? Thanks Neil On Tue, May 26, 2009 at 12:56 AM, Niklas Broberg wrote: > Hi all, > > In preparation for my GSoC project, I've set up some new > infrastructure for the haskell-src-exts package. Instead of re

Re: [Haskell-cafe] No VerboseCheck in QuickCheck 2?

Hi, I don't think I am familiar enough with QuickCheck 2. But there seems to be no verboseCheck like function, and sample and sample' is useful to printing test cases. ghci> sample (arbitrary :: Gen Int) 1 0 1 -2 -2 -5 -16 -9 -57 -115 -94 ghci>

Re: [Haskell-cafe] Haskell programmer s in São Carlos - SP - Brazil?

Is there already any mailing list or group in Portuguese? I would like that if it were a list for Portuguese speakers, no matter they are from Portugal or Moçambique. Maurício > Hey, we have enough people for a São Paulo Haskell User Group. > Anyone else interested? > > Best regards, > Daniel Y

Re: [Haskell-cafe] the problem of design by negation

On Tue, 26 May 2009, Richard O'Keefe wrote: > > I have one of Brian Marick's (www.exampler.com) stickers on my door. > It reads > to be less wrong than yesterday > > Two quotes I often give my students: > Brethren, I beseech you in the bowels of Christ, > consider it _possible_ th

Re: [Haskell-cafe] Haskell programmers in São Carlo s - SP - Brazil?

I don't think there's one, but I would subscribe to it. -- []s, Andrei Formiga 2009/5/26 Maurício : > Is there already any mailing list or group in Portuguese? I would > like that if it were a list for Portuguese speakers, no matter > they are from Portugal or Moçambique. > > Maurício > > >> He

RE: [Haskell-cafe] Anglohaskell?

I agree, I'd love to see this happen. Like everyone else, I don't have much time, but can do grunt work if there's any to be done, and will happily support anyone who does take up the mantel. Cheers, Sam -Original Message- From: haskell-cafe-boun...@haskell.org on behalf of Neil Mitche

Re: [Haskell-cafe] Haskell programmers in São Carlos - SP - Brazil?

On Tue, May 26, 2009 at 12:42:12PM -0300, Andrei Formiga wrote: > I don't think there's one, but I would subscribe to it. I would as well, but what would we gain with it? Wouldn't it rot because every message one of us wanted to post was general enough to just post on haskell-cafe? Would it be a

[Haskell-cafe] Re: ANN: New repository and trac for haskell-src-exts

> Do you want people to cc bugs they want to "vote" for - like the GHC people > do? Absolutely. Seeing the relative interest in various features would definitely be helpful in steering my (and others') efforts. /Niklas ___ Haskell-Cafe mailing list Has

[Haskell-cafe] May all logos be freely used?

Hello, What's the status of the logos on http://www.haskell.org/logos/results.html I'd like to use one or more in an about message in a Haskell program. Is this allowed, and if so, are there any conditions? I've just looked at them again, and it's a really fine collection, I think. Best Regards

Re: [Haskell-cafe] May all logos be freely used?

>From http://haskell.org/haskellwiki/Haskell_logos/New_logo_ideas : "Please submit your entries here, and attach your name to them please. To be eligible, they will need to be visible on this page (e.g. uploaded, or link to the image). The image should be freely available (a suitable freely distri

[Haskell-cafe] The Computer Language Benchmarks Game: pidigits

On Mon May 25 16:18:29 EDT 2009, Arnaud Payement wrote: > ... I thought it is better to show Haskell as one would naturally write it. One would naturally first write it in C ? :-) ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://w

Re: [Haskell-cafe] A problem with par and modules boundaries...

On Mon, 2009-05-25 at 09:40 -0400, Mario Blazevic wrote: > >> $diff main.simpl imported.simpl > >> ... > >> 223c232 > >> < a_s1rs [ALWAYS Just L] :: GHC.Integer.Internals.Integer > >> --- > >>> a_s1sV [ALWAYS Just S] :: GHC.Integer.Internals.Integer > >> ... > > > > Good find! > > > >

[Haskell-cafe] Re: Haskell programmers in São Carlos - SP - Brazil?

> I would as well, but what would we gain with it? Wouldn't it rot > because every message one of us wanted to post was general enough > to just post on haskell-cafe? Would it be able to attract > Portuguese-speaking people that aren't fluent English speakers? > > I'm not being pessimistic, just

[Haskell-cafe] Purely logical programming language

There are a number of ways to marry purely functional programming languages with IO. To name just two possibilities: Clean uses linear types, threading exactly one "World" through functions, Haskell uses Monads. The model in Prolog, however, looks more like the model used in most strict functiona

Re: [Haskell-cafe] How to implement this? A case for scoped record labels?

On Tue, May 26, 2009 at 4:32 AM, wren ng thornton wrote: > One alternative is to use Haskell's support for ad-hoc overloading. Define a > typeclass for each selector (or group of selectors that must always occur > together) which is polymorphic in the record type. [...] > It's not pretty, but it g

Re: [Haskell-cafe] Purely logical programming language

On Tue, May 26, 2009 at 09:10:10PM +0200, Matthias Görgens wrote: > The model in Prolog, however, looks more like the model used in most > strict functional languages. It uses impure predicates to affect the > outside world. Do you know of any attempt to do for logic programming > what Monads did

Re: [Haskell-cafe] Purely logical programming language

> Mercury also has type classes and other Haskellisms, so if you're > interested in "doing Prolog the Haskell way", you should definitely > have a look at it. Thanks. I'll have a look. (I also just found Mercury on my own: After I posed my original question, I tried another web search, and found

Re: [Haskell-cafe] Purely logical programming language

Hi, On 26.05.2009, at 21:24, Lauri Alanko wrote: Mercury also has type classes and other Haskellisms, so if you're interested in "doing Prolog the Haskell way", you should definitely have a look at it. I have to admit that I am not very familiar with Mercury. But if you are looking for "doi

[Haskell-cafe] How does GHC's implementation of par work?

This is related to the long thread on a bug in cross-module strictness analysis for the "lazy" function in GHC. Simon posted a response to that bug ( http://hackage.haskell.org/trac/ghc/ticket/3259 ), which shows the Haskell source for GHC's "par" function: > {-# INLINE par #-} > par :: a -> b -

Re: [Haskell-cafe] Purely logical programming language

On Tue, 26 May 2009, Jan Christiansen wrote: Hi, On 26.05.2009, at 21:24, Lauri Alanko wrote: Mercury also has type classes and other Haskellisms, so if you're interested in "doing Prolog the Haskell way", you should definitely have a look at it. I have to admit that I am not very familiar

[Haskell-cafe] [wxHaskell] ghc-pkg: /usr/local/lib/imports doesn't exist ...

Hello, I'm installing wxhaskell from darcs, almost all found good, but after make "# runghc Setup.lhs install" the last lines this is: cat config/wxcore.pkg | sed -e "s|\${wxhlibdir}|/usr/local/lib|" | ghc-pkg update - Reading package info from stdin ... done. ghc-pkg: /usr/local/lib/imports d

Re: [Haskell-cafe] How to implement this? A case for scoped record labels?

ntu...@googlemail.com wrote: wren ng thornton wrote: > A better approach would > probably be to use GADTs or the new data families which give a sort of dual > of typeclasses (typeclasses give a small set of functions for a large set of > types; GADTs give a large set of functions for a small set

Re: [Haskell-cafe] Design in Haskell?

> Are there any suggestions of wikis, books or particularly > well-architected and readable projects I could look at to about learn > larger-scale design in Haskell? I've recently found Brent Yorgey's The Typeclassopedia very helpful. You can find it in The Monad.Reader Issue 13. It's similar to

[Haskell-cafe] Re: Purely logical programming language

Henning Thielemann wrote: On Tue, 26 May 2009, Jan Christiansen wrote: Hi, On 26.05.2009, at 21:24, Lauri Alanko wrote: Mercury also has type classes and other Haskellisms, so if you're interested in "doing Prolog the Haskell way", you should definitely have a look at it. I have to admit

Re: [Haskell-cafe] I love purity, but it's killing me.

Hi Tom, I've been working on another code-generating graphics compiler, generating GPU code. As always, I run into the problem of efficient common subexpression elimination. In Pan, Vertigo & Pajama, I used lazy memoization, using stable pointers and weak references, to avoid the worst-case-expo

[Haskell-cafe] Lazy Parsing

Hi all, is it possible to do lazy parsing with Parsec? I understand that one can do that with polyparse, don't know about uulib, but I happen to be already somewhat familiar with Parsec, so before I do switch to polyparse I rather make sure I actually have to. The files it has to parse is an

Re: [Haskell-cafe] How to implement this? A case for scoped record labels?

I wonder if I am completely off here, but I am surprised that there is no progress on the scoped labels front. The Haskell wiki mentioned that the status quo is due to a missing optimum in the design space, but the same can be said about generic programming in Haskell and yet, GHC ships with Scrap

[Haskell-cafe] trying to understand space leaks....

In Section 2.5 of "Generalizing Monads to Arrows" paper (link) John Huges talks about the space leak inherit in monadic implementation of backtracking parsers. newtype Parser s a = P( [s] => Maybe (a, [s])) instance MonadPlus Parser where

Re: [Haskell-cafe] I love purity, but it's killing me.

Conal Elliott wrote: Hi Tom, I've been working on another code-generating graphics compiler, generating GPU code. As always, I run into the problem of efficient common subexpression elimination. In Pan, Vertigo & Pajama, I used lazy memoization, using stable pointers and weak references, to av

Re: [Haskell-cafe] I love purity, but it's killing me.

On Tue, May 26, 2009 at 6:49 PM, Conal Elliott wrote: > Hi Tom, > > I've been working on another code-generating graphics compiler, generating > GPU code.  As always, I run into the problem of efficient common > subexpression elimination.  In Pan, Vertigo & Pajama, I used lazy > memoization, using

Re: [Haskell-cafe] How does GHC's implementation of par work?

2009/5/26 Ryan Ingram : > What causes par# to > get executed?  Does GHC overload case for unboxed return values to > force the evaluation of the scrutinee even if its return value isn't > used? As you noted, the type of "par" is a -> Int#. Furthermore, the only possible evaluation semantics for un

Re: [Haskell-cafe] trying to understand space leaks....

On Tue, May 26, 2009 at 5:03 PM, Daryoush Mehrtash wrote: > newtype Parser s a = P( [s] -> Maybe (a, [s])) (fixed typo) > instance MonadPlus  Parser where >   P a mplus P b = P (\s -> case a s of >     Just (x, s') -> Just (x, s') >     Nothing

Re: [Haskell-cafe] Design in Haskell?

On Wed, May 27, 2009 at 6:50 AM, Michael Steele wrote: > > I've recently found Brent Yorgey's The Typeclassopedia very helpful. > You can find it in The Monad.Reader Issue 13. It's great, thank you Michael. lee ___ Haskell-Cafe mailing list Haskell-Caf

Re: [Haskell-cafe] How does GHC's implementation of par work?

I saw your paper on LtU last week. Here's an extra plug: I really enjoyed it. When can we expect to see Strict Core replacing System Fc? :) -- ryan On Tue, May 26, 2009 at 5:32 PM, Max Bolingbroke wrote: > 2009/5/26 Ryan Ingram : >> What causes par# to >> get executed?  Does GHC overload ca

Re: [Haskell-cafe] Design in Haskell?

If you are coming from Object Oriented background, I think, the best book to read is the Paul Hudak's "Haskell School of Expression". It goes through a design of a game application. The book is also available on line in google books. daryoush On Mon, May 25, 2009 at 1:22 AM, Dan wrote: > H

Re: [Haskell-cafe] Bidirectional programming in Haskell

Hi, 2009/5/26 Janis Voigtlaender : > On Hackage: > > http://hackage.haskell.org/cgi-bin/hackage-scripts/package/bff-0.1 > > The underlying research: > > http://wwwtcs.inf.tu-dresden.de/~voigt/popl09-2.pdf > > A web interface for playing with the library: > > http://linux.tcs.inf.tu-dresden.de/~bff

Re: [Haskell-cafe] May all logos be freely used?

On Tue, 2009-05-26 at 18:36 +0200, Max Rabkin wrote: > So at least any logos on the wiki should be usable under that license. Furthermore, I released all my logos (the lambda/bind combination that won) into the Public Domain. Of course, derive from them as you wish, and there are a couple of tool