Re: [Haskell-cafe] IO and Wash

On Wed, Feb 16, 2005 at 04:13:04AM +, John Goerzen wrote: > I'm trying out WASH for a project. It looks nice, but I/O looks tricky. > I have a database lookup, and I want to present each row as an option > for the user. Page 15 of the Wash user-manual.pdf has an example of > using the abstrac

Re: [Haskell-cafe] Unsafe IO and Wash

On Wed, Feb 16, 2005 at 04:33:29AM +, John Goerzen wrote: > On a related note, Wash seems to be preserving all sorts of unnecessary > "state" from previous screens a user visited. You do know that the current version of WASH rebuilds the continuation by repeating all the previous steps, don't

[Haskell-cafe] Unsafe IO and Wash

On a related note, Wash seems to be preserving all sorts of unnecessary "state" from previous screens a user visited. I don't understand why it doesn't pass only the parameters to the next screen; that should be easily determined to be all that is necessary. On that same topic, I've used Wash's u

[Haskell-cafe] IO and Wash

I'm trying out WASH for a project. It looks nice, but I/O looks tricky. I have a database lookup, and I want to present each row as an option for the user. Page 15 of the Wash user-manual.pdf has an example of using the abstract table to do this. It works fine, but... if a user hits the submit b

Re: [Haskell-cafe] Problems with building GCJNI 1.2

On Tue, 15 Feb 2005 22:33:30 +0100, Dmitri Pissarenko <[EMAIL PROTECTED]> wrote: > Hello! > > I am trying to build GCJNI 1.2 under Windows (cygwin) with GHC 6.2.1 and Green > Card 3.01. > > I am getting following error messages when entering "make". > > > $ make > make -C src > make[1]: Enterin

[Haskell-cafe] Problems with building GCJNI 1.2

Hello! I am trying to build GCJNI 1.2 under Windows (cygwin) with GHC 6.2.1 and Green Card 3.01. I am getting following error messages when entering "make". $ make make -C src make[1]: Entering directory `/cygdrive/c/dapWork/temp/downloads/gcjni/gcjni- 1.2/ src' gcc -MM -I/cygdrive/c/Programme/

Re: [Haskell-cafe] Problems building GreenCard

Hello! I could fix the problem by replacing the line GHC_OPTS = -cpp -fglasgow-exts -fno-prune-tydecls in file lib/Makefile by this one GHC_OPTS = -cpp -fglasgow-exts However, I don't know what this -fno-prune-tydecls does and whether it is important (for using Green Card to access Java). Best rega

[Haskell-cafe] Problems building GreenCard

Hello! I'm trying to build GreenCard 3.01 (latest release according to http://www.haskell.org/greencard/) under Windows with cygwin and GHC 6.2.1. I'm getting these errors: $ make prefix=/cygdrive/c/Programme/GreenCard/ install install-pkg make[1]: Entering directory `/cygdrive/c/dapWork/temp/d

Re: [Haskell-cafe] Parsing in Haskell

I've used Parsec for small and more complex parsing tasks, and found it works well for both. In the past, I've used parser generators (not with Haskell), but now I find that I prefer to express a parser directly in the main programming language I'm using ... that way, it's easier to "escape" th

RE: [Haskell-cafe] Parsing in Haskell

On 15 February 2005 10:36, Johan Glimming wrote: > I want to implement a little algebraic specification language in > Haskell, and I have a working C implementation available which uses > yacc/flex. > > What is the best way of replacing yacc/bison and (f)lex when migrating > the project into Hask

Re: [Haskell-cafe] What is MonadPlus good for?

Here's an example: In my paper "First Class Patterns" , by defining the pattern combinators using MonadPlus, you get standard pattern matching with the Maybe instance of MonadPlus and you get backtracking pattern matching with the [] (list) insta

Re: [Haskell-cafe] What is MonadPlus good for?

On Mon, 14 Feb 2005 19:01:53 -0500, [EMAIL PROTECTED] <[EMAIL PROTECTED]> wrote: > I was thinking more along the lines of Ralf Hinze's nondeterminism > transformer monad: > > http://haskell.org/hawiki/NonDeterminism > > The relevant instance is this: > > instance (Monad m) => MonadPlus (

[Haskell-cafe] Re: Parsing in Haskell

Johan Glimming writes: > What is the best way of replacing yacc/bison and (f)lex when > migrating the project into Haskell? My favorite tool for writing parsers is this one: http://www.cs.chalmers.se/~markus/BNFC/ You give it a grammar in BNF notation, and it will generate parsers and appro

Re: [Haskell-cafe] Parsing in Haskell

On 15 Feb 2005, at 10:36, Johan Glimming wrote: Hi I want to implement a little algebraic specification language in Haskell, and I have a working C implementation available which uses yacc/flex. What is the best way of replacing yacc/bison and (f)lex when migrating the project into Haskell? I

Re: [Haskell-cafe] Point-free style

Am Dienstag, 15. Februar 2005 00:42 schrieben Sie: > On Feb 14, 2005, at 2:07 AM, Daniel Fischer wrote: > > A question for the point-free society: > > Is there any advantage of defining > > > > (.<) = (.) . (.) > > > > rather than > > > > f .< g = \x y -> f (g x y) -- or f $ g x y ? > > > > An

[Haskell-cafe] Parsing in Haskell

Hi I want to implement a little algebraic specification language in Haskell, and I have a working C implementation available which uses yacc/flex. What is the best way of replacing yacc/bison and (f)lex when migrating the project into Haskell? Best Wishes, Johan ___

Re: [Haskell-cafe] Point-free style (Was: Things to avoid)

[I drafted this response some time ago, but didn't send it, so apologies if I am re-covering old ground...] At 09:23 10/02/05 -0500, Jan-Willem Maessen wrote: If you're trying to avoid obscurity, why advocate point-free style? Some time ago, I asked an experienced Haskell programmer about the ext

Re: [Haskell-cafe] Point-free style

At 09:00 11/02/05 +0100, Ketil Malde wrote: Matthew Roberts <[EMAIL PROTECTED]> writes: >> [Point-free] compositions of functions with arity greater than 1, >> [...] compositions of sections of composition or application, >> arrow notation without the sugar, and so forth---will always be more >> di

[Haskell-cafe] RDF and stuff (was: Point-free style ...)

At 23:00 10/02/05 -0500, David Menendez wrote: Here's another one: addTriple (s,p,o) = addArc s p o . addNode s . addNode p . addNode o It looks like you're playing around with RDF here. A quick check of your web site shows a Semantic Web angle to some of your workings. I also see you show