Re: [Haskell-cafe] A question on existential types and Church encoding

On Sat, May 29, 2010 at 9:28 PM, Cory Knapp wrote: > Hello, > > A professor of mine was recently playing around during a lecture with > Church booleans (I.e., true = \x y -> x; false = \x y -> y) in Scala and > OCaml. I missed what he did, so I reworked it in Haskell and got this: > > >type CB a

[Haskell-cafe] A question on existential types and Church encoding

Hello, A professor of mine was recently playing around during a lecture with Church booleans (I.e., true = \x y -> x; false = \x y -> y) in Scala and OCaml. I missed what he did, so I reworked it in Haskell and got this: >type CB a = a -> a -> a >ct :: CB aC >ct x y = x >cf :: CB a >cf x y = y

Re: [Haskell-cafe] Re: Proposal to solve Haskell's MPTC dilemma

On 05/29/10 21:24, Carlos Camarao wrote: The situation is as if we a FD: Well, that is indeed equivalent here in the second argument of class F, but I constructed the example to show an issue in the class's *first* argument. Notice you needed to add type-signatures, on the functions you nam

Re: [Haskell-cafe] Re: Proposal to solve Haskell's MPTC dilemma

On Fri, May 28, 2010 at 2:36 AM, Isaac Dupree < m...@isaac.cedarswampstudios.org> wrote: > On 05/27/10 17:42, Carlos Camarao wrote: > >> On Thu, May 27, 2010 at 5:43 PM, David Menendez >> wrote: >> >> On Thu, May 27, 2010 at 10:39 AM, Carlos Camarao >>> wrote: >>> Isaac Dupree: >

Re: [Haskell-cafe] Why Either = Left | Right instead of something like Result = Success | Failure

Vo Minh Thu wrote: Control.Monad.Error provides an instance for Either. Donn Cave wrote: >>> ... in the mtl transformer library, in case anyone else besides >>> myself didn't know that. And I see it has to be there because >>> it depends on the Error typeclass. Daniel Fischer writes: >> Whi

Re: [Haskell-cafe] Reproducible Bug in Emacs' haskell-mode

Try the following: 1) M-x toggle-debug-on-quit (so that it's enabled) 2) Follow your instructions below 3) When it's stuck, do C-g to stop it trying to load the file. Just so you know, there's also a dedicated mailing list for the Haskell mode in Emacs; see here for more information: http://pro

Re: [Haskell-cafe] Re: [web-devel] Google Summer of Code: BlazeHTML RFC

Matt Parker writes: > Q3: Which HTML version would you preferably use? > > HTML 5. google summer of code should be about pushing the new and exciting.  Yes, definitely, this should be the default IMO. G -- Gregory Collins ___ Haskell-Cafe mailin

[Haskell-cafe] Re: [web-devel] Google Summer of Code: BlazeHTML RFC

> Q3: Which HTML version would you preferably use? > HTML 5. google summer of code should be about pushing the new and exciting. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe

[Haskell-cafe] Reproducible Bug in Emacs' haskell-mode

Hi all, I have a reproducible bug in Emacs' Haskell mode where Emacs gets stuck in an endless loop. I am using GNU Emacs 23.0.93.1. To reproduce: 1. Use a bad Language pragma eg. {-# LANGUAGE FlexibleTypes #-} 2. Load a GHCI instance with C-c C-l. GHCI outputs the following error: unsupported e

[Haskell-cafe] Re: [Haskell] Re: Work on Video Games in Haskell

Edward Kmett writes: > On Wed, May 26, 2010 at 5:22 PM, Pierre-Etienne Meunier dir="ltr"> wrote: > Well in this case I'd be really interested in seeing how the can tell the > difference, be it only from a simple complexity theoretic point of view ! I > u

[Haskell-cafe] Re: Math questions

Mujtaba Boori wrote: sure I did enjoy the discussion here Yitzchak Gale. I have already submitted several questions ,and you guys were very helpful. However , I am not sure how I will use Haskell other than my Haskell course that has just finished. I would very much recommend the Real World Ha

Re: [Haskell-cafe] Wire GUI

Conal Elliot's talk on "Tangible Functional Programming" might be of interest. http://www.youtube.com/watch?v=faJ8N0giqzw On 29 May 2010 09:43, Andrew Coppin wrote: > Malcolm Wallace wrote: >>> >>> I'm looking at a project which involves a GUI where you can insert >>> components and wire up conne

Re: [Haskell-cafe] Wire GUI

Malcolm Wallace wrote: I'm looking at a project which involves a GUI where you can insert components and wire up connections between them. Obviously the details of what the components are and what code gets executed for them is domain-specific, however the general idea of graphically wiring th

Re: [Haskell-cafe] How to fix this problem in FreeBSD ?

>ghc --version The Glorious Glasgow Haskell Compilation System, version 6.10.4 >cabal --version cabal-install version 0.8.2 using version 1.8.0.2 of the Cabal library >cat Makefile # New ports collection makefile for: hs-ghc-paths # Date created:July 09 2009 # Whom:Giuse

Re: [Haskell-cafe] How to fix this problem in FreeBSD ?

Which version of GHC, which version of Cabal, and what is the Makefile? zaxis writes: > /usr/ports/devel/hs-ghc-paths>sudo make install clean > ===> hs-ghc-paths-0.1.0.5_1 depends on executable: ghc - found > ===> Configuring for hs-ghc-paths-0.1.0.5_1 > [1 of 1] Compiling Main (