Re: [Haskell-cafe] Beginner Question

Hi Vishy, You wrote: I have just started on my journey in learning Haskell. Welcome aboard! We all wish you an enjoyable and (type)safe trip. I have started off reading wikibook, then will read yet another tutorial on haskell. Please guide me if I am on right track Those are both great

Re: [Haskell-cafe] IO is not a monad

Lennart Augustsson wrote: I think seq is funny because it is not lambda definable. I wrote: Does the set of computable functions on the natural numbers defined by the lambda calculus augmented with seq have higher Turing degree than the set of classical computable functions? I guess I was

[Haskell-cafe] FFI basics

Hi, I would like to use FFI for the first time. Can someone give me a really, really simple complete example? I want to be able to take a simple C program and access a function from it in Haskell. A simple example of the other way around would be nice, too, but I don't happen to need that just

Re: [Haskell-cafe] FFI basics

I would like to use FFI for the first time. Can someone give me a really, really simple complete example? Everything I found on the wiki seems way beyond that - maybe I missed it. I am using GHC. I am not using Windows. From the old wiki: http://www.haskell.org/hawiki/FfiCookbook

Re: [Haskell-cafe] FFI basics

Hello Yitzchak, Friday, February 9, 2007, 3:23:53 PM, you wrote: I would like to use FFI for the first time. Can someone give me a really, really simple complete example? nothing can be easier main = print (c_mysin 1.0) foreign import ccall mysin.h mysin c_mysin :: Double - Double

[Haskell-cafe] factorising to prime numbers

Hi folks, I recently read in my copy of Concrete Mathematics the relationship between prime factors powers and lcm/gcd functions. So I decided to reimplement gcd and lcm the long way, for no other reason than because I could. If you look at the definition of 'powers' you'll note it's infinite.

Re: [Haskell-cafe] factorising to prime numbers

If you look at the definition of 'powers' you'll note it's infinite. So there's no easy way to take the product of this list, if I don't know how many items to take from it. So you need finite lists. -- how many of the prime p are in the unique factorisation -- of the integer n?

Re: [Haskell-cafe] factorising to prime numbers

On Feb 9, 2007, at 9:20 AM, Dougal Stanton wrote: Hi folks, I recently read in my copy of Concrete Mathematics the relationship between prime factors powers and lcm/gcd functions. So I decided to reimplement gcd and lcm the long way, for no other reason than because I could. If you look at

Re: [Haskell-cafe] factorising to prime numbers

On Fri, 9 Feb 2007, Dougal Stanton wrote: Hi folks, I recently read in my copy of Concrete Mathematics the relationship between prime factors powers and lcm/gcd functions. So I decided to reimplement gcd and lcm the long way, for no other reason than because I could. If you look at the

[Haskell-cafe] GHC throws IOError on Win32 when there is no console

Hi, I noticed on Windows that when I use IO functions that write to stdout when the process is lacking a console, those functions throw an IOError. I'm not sure if this also occurs for stderr because I haven't tried it. Some classes of processes are created without a console because they never

[Haskell-cafe] Re: GHC throws IOError on Win32 when there is no console

Sorry, I should clarify. I am writing about applications compiled with GHC. -John On 2/10/07, John Ky [EMAIL PROTECTED] wrote: Hi, I noticed on Windows that when I use IO functions that write to stdout when the process is lacking a console, those functions throw an IOError. I'm not sure if

Re: [Haskell-cafe] GHC throws IOError on Win32 when there is no console

On 09/02/07, John Ky [EMAIL PROTECTED] wrote: I noticed on Windows that when I use IO functions that write to stdout when the process is lacking a console, those functions throw an IOError. I'm not sure if this also occurs for stderr because I haven't tried it. This is Windows standard

[Haskell-cafe] Random numbers without IO

Well, nobody likes tainting their beautiful pure code with IO, so I rewrote the Random module to take advantage of the latest research [1]: module Random where getRandom = 4 Cheers, D. [1] http://xkcd.com/c221.html -- Dougal Stanton ___

[Haskell-cafe] What's wrong with cgi-undecidable?

http://darcs.haskell.org/packages/cgi-undecidable/ There only 3 or 4 lines of source code, but it can't be installed. The ghc version is 6.6 . Undecidable.hs:23:0: Duplicate instance declarations: instance [overlap ok] (MonadTrans t, MonadCGI m, Monad (t m)) =

Re: [Haskell-cafe] Random numbers without IO

That's definitely the lazy approach! On 2/9/07, Dougal Stanton [EMAIL PROTECTED] wrote: Well, nobody likes tainting their beautiful pure code with IO, so I rewrote the Random module to take advantage of the latest research [1]: module Random where getRandom = 4 Cheers, D. [1]

Re: [Haskell-cafe] What's wrong with cgi-undecidable?

http://darcs.haskell.org/packages/cgi-undecidable/ There only 3 or 4 lines of source code, but it can't be installed. The ghc version is 6.6 . Undecidable.hs:23:0: Duplicate instance declarations: instance [overlap ok] (MonadTrans t, MonadCGI m, Monad (t m)) =

[Haskell-cafe] Tricks for making low level haskell hacking easier

For those of you who like your Haskell code fast, then, if you're like me, reading Core output all day can give you headaches. Here's a couple of tricks I use to make optimising low level stuff easier. 1) Use Hscolour to pretty-ifiy the Core so its more parsable: ghc -O Foo.hs -ddump-simpl

[Haskell-cafe] Query

hi i am going through yaht tutorial and exercise 4.6 and 4.7..i understood 4.6,but not 4.7 in which fromTuple (One a ) = Left (Left a ) and fromTuple (Two a b ) = Left (Right (a,b) ) function r written..why use Either type..cant i just say fromTuple (Two a b )=(a,b)