There's a 'powerset' thread on this list [1][2] starting 4th June which I
think contains some of the answers you seek. Read and you shall learn!
#g
--
[1] List archive: http://www.haskell.org/pipermail/haskell-cafe/
[2] Powerset thread
starts:
Hi everyone,
I have written the following program to find magic numbers i.e. integers 'n' such
that both (n+1) and (n/2+1) are perfect squares.
-- Program to find magic numbers
Import IO
main :: IO ()
main =
do
print (filter magicP sqs)
sqs :: [Int]
sqs = [x*x | x -
I've managed to get a segfault in haskell! And without even using the
FFI... actually my code uses the FFI, but the changes that triggered the
segfault don't involve that, they just use Text.Regex.
The code that triggers the segfault is the function produced by:
filetype_function :: IO (FilePath
Trying to get the hang of exceptions...
I would expect this program:
module Main where
import Control.Exception hiding (GHC.Prelude.catch)
temp :: IO ()
temp = do
putStrLn line 1
ioError (AssertionFailed my temp)
handler :: Exception - IO ()
handler e = putStrLn (exception: ++
On Mon, Jul 21, 2003 at 02:12:02PM +0100, Bayley, Alistair wrote:
module Main where
import Control.Exception hiding (GHC.Prelude.catch)
This hiding clause is illegal. But anyway what you want is
import Prelude hiding (catch)
import Control.Exception
Prelude.catch only catches Haskell 98
If I try to run the program (compiled using GHC 6), it calculates all
members of the list and then prints the whole list in the end. Since
Haskell is 'lazy' I was expecting behaviour similar to HUGS where it prints
the numbers as it finds them. Does this behaviour have something to do with
I'm looking for a way to return an arbitrary exit code to the OS. The
standard `exitWith' function does the job, but unfortunately it also has
the side-effect of reporting an exception (I'm using GHC 6.0, with
Control.Exception imported for other purposes).
When a fatal error occurs, my program
