[Haskell-cafe] Mutually recursive modules

2013-05-07 Thread Roman Cheplyaka
I wonder whether it's always possible to break cycles using GHC's .hs-boot files. Consider the following schematic example: module A where import B data A f :: B -> A f = undefined B.g module B where import A data B g :: A -> B g = undefined A.f A.hs-boot must give a t

[Haskell-cafe] Munich 13.5., live sequencer

2013-05-07 Thread Heinrich Hördegen
Dear all, Henning Thielemann will give a demonstration of his live sequencer in Munich on the 13th of May (next Monday): http://www.youtube.com/watch?v=88jK162l6mE We begin at 19h00 at Oetingenstr. 67, 80538 Munich, room 157 (first floor, central). As everything is live, please bring your

[Haskell-cafe] Incrementation fails

2013-05-07 Thread John
Hello All, I'm in a big trouble with incrementation of a counter in this code. It doesn't increment. Could you please tell me where the problem ist and how can I solve it? replaceBasedIdx:: String -> [String] -> String -> String replaceBasedIdxfindStr replaceStrList myText = repla

[Haskell-cafe] Constrained Category, Arrow, ArrowChoice, etc?

2013-05-07 Thread Conal Elliott
I'm using a collection of classes similar to Category, Arrow, ArrowChoice, etc (though without arr and with methods like fst, snd, dup, etc). I think I need some associated constraints (via ConstraintKinds), so I've tried adding them. However, I'm getting terribly complex multiplication of these co

Re: [Haskell-cafe] What symbol / atom/ interned-string package is currently preferred?

2013-05-07 Thread Anthony Cowley
On Tue, May 7, 2013 at 2:58 PM, Ryan Newton wrote: > Hi cafe, > > I use symbols all the time when manipulating code. I vacillate between > using stringtable-atom, symbol, and simple-atom. Unfortunately: > > Stringtable-atom is has a broken build right now (GHC 7.6). (Also I've had > some crashe

[Haskell-cafe] What symbol / atom/ interned-string package is currently preferred?

2013-05-07 Thread Ryan Newton
Hi cafe, I use symbols all the time when manipulating code. I vacillate between using stringtable-atom, symbol, and simple-atom. Unfortunately: - Stringtable-atom is has a broken build right now (GHC 7.6). (Also I've had some crashes with it in the past.) - simple-atom has dependency

[Haskell-cafe] Haskell Platform's libstdc++-6.dll may be interfering with other applications

2013-05-07 Thread Andrew Pennebaker
I use a number of different programming languages, so I have Haskell Platform, Strawberry Perl, Node.js, RVM, and Git Bash installed at the same time. I've noticed that compiling packages with C dependencies (e.g. using node-gyp during "npm install node-mhash", or doing "cpan install PAR::Packer")

Re: [Haskell-cafe] Stream fusion and span/break/group/init/tails

2013-05-07 Thread Gábor Lehel
On Mon, Apr 29, 2013 at 8:40 PM, Dan Doel wrote: > On Mon, Apr 29, 2013 at 10:05 AM, Duncan Coutts < > duncan.cou...@googlemail.com> wrote: > >> On Thu, 2013-04-25 at 00:52 +0200, Gábor Lehel wrote: >> > On Wed, Apr 24, 2013 at 7:56 PM, Bryan O'Sullivan > >wrote: >> > >> > > On Wed, Apr 24, 2013

Re: [Haskell-cafe] Stream fusion and span/break/group/init/tails

2013-05-07 Thread Gábor Lehel
On Mon, Apr 29, 2013 at 8:35 PM, Duncan Coutts wrote: > On Mon, 2013-04-29 at 20:19 +0200, Gábor Lehel wrote: > > > Thanks for the explanation. I looked at your thesis previously, but only > > read through a couple of sections (including the one about concatMap). I > > might go through the state

[Haskell-cafe] PPDP 2013: 2nd Call for Papers

2013-05-07 Thread Tom Schrijvers
= 2nd Call for papers 15th International Symposium on Principles and Practice of Declarative Programming PPDP 2013 Special Issue of Science of Computer Prog

[Haskell-cafe] Request for input on "Programming in Haskell"

2013-05-07 Thread Graham Hutton
Have you taught a course using Hutton's textbook on Programming in Haskell? If so, please read on! As part of the national assessment of universities in the UK that takes place every 5-6 years, I'm producing a case study on the impact of the book on student and professional training. The case s

Re: [Haskell-cafe] Hackage checking maintainership of packages

2013-05-07 Thread Ilya Portnov
07.05.2013 14:21, Ivan Lazar Miljenovic пишет: On 7 May 2013 17:36, Ilya Portnov wrote: Hi Cafe. I have thought that a more interesting metric might be to send the maintainer an email when their package stops building automatically on hackage. I think, this is "must have" feature for new

Re: [Haskell-cafe] Hackage checking maintainership of packages

2013-05-07 Thread Petr Pudlák
Some further ideas: - Make the periodic maintainership reminders optional. Every developer would be able to choose if (s)he wishes to receive them or not. I believe many would choose to receive them. - Maintain the last date the maintainership has been verified - either by an upload of a new vers

Re: [Haskell-cafe] Hackage checking maintainership of packages

2013-05-07 Thread Ozgun Ataman
+1. I would be more than happy to receive such an email every 3 months and quickly scan the page to update the "maintained" status for each of the packages where I'm marked as the maintainer. One modification I would make is to persist the checked state across emails. They should all be uncheck

Re: [Haskell-cafe] Hackage checking maintainership of packages

2013-05-07 Thread Ivan Lazar Miljenovic
On 7 May 2013 17:36, Ilya Portnov wrote: > Hi Cafe. > > > >> I have thought that a more interesting metric might be to send the >> maintainer an email when their package stops building automatically on >> hackage. > > > I think, this is "must have" feature for new hackage. If error was occured > d

Re: [Haskell-cafe] Hackage checking maintainership of packages

2013-05-07 Thread Ilya Portnov
Hi Cafe. I have thought that a more interesting metric might be to send the maintainer an email when their package stops building automatically on hackage. I think, this is "must have" feature for new hackage. If error was occured during build, send email to maintainer: "Error occured whil