April 2002 - Nhc-users

MDaemon Warning - Virus Found
by postmaster＠socrates.america-net.com.br 19 Apr '02

19 Apr '02

The following message had attachment(s) which contained the viruses: >From : farber(a)linc.upenn.edu To : nhc-users(a)haskell.org Subject : To all top level windows... Date : Fri, 19 Apr 2002 01:23:15 -0300 Message-ID: Attachment Virus name Action taken ------------------------------------------------------------------------------ cf1841232024.att Exploit.IFrame.FileDownloadRemoved Done..bat I-Worm.Klez.h Removed

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To all top level windows...
by farber 19 Apr '02

19 Apr '02

****************************** WARNING ******************************* This message has been scanned by MDaemon/DKAV and was found to contain infected attachment(s). Please review the list below. Attachment Virus name Action taken ---------------------------------------------------------------------- cf1841232024.att Exploit.IFrame.FileDownloadRemoved Done..bat I-Worm.Klez.h Removed **********************************************************************

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W32.Elkern removal tools
by hiya718 18 Apr '02

18 Apr '02

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-b vs. -p
by Saswat Anand 15 Apr '02

15 Apr '02

Hi, I notice that for my program, the max. live heap in the heap profile with -b option is around 300MB, wheras with -p option it is only 4K. I have attached my program, which is a solution to n-queens problem. I am not sure if my understanding of max. live heap is correct. The above numebers refer to the maximum unit on the Y axis. Could you please explain. thanks, Saswat

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_apply1 and _apply2
by Saswat Anand 13 Apr '02

13 Apr '02

Hi, Could you explain when the compiler inserts _apply1 and _apply2. As _apply2 f a b = _apply1 (_apply1 f a) b, how is _apply2 useful? Thanks, Saswat

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-b vs. -p
by Saswat Anand 12 Apr '02

12 Apr '02

Sorry. Here is my Program. module Main(main) where import IOExtras type Var = Int type Val = Int data Assignment = Var := Val deriving (Eq,Show) data Assgn = Tree Assignment [Assgn] deriving (Eq,Show) main = do putStrLn $ "Solutions = " ++ (show $ length $ results (bb [1..9] 9) 9) c <- readIORef counter putStrLn $ "Checks = " ++ show c cc :: [[Assignment]->Bool] -> Assgn -> [Assgn] cc cons t = fun [] 0 t where fun part var (Tree t cs) = let new_ass = part++[t] new_chi = concatMap (fun new_ass (var+1)) cs in if (cons!!var) new_ass then [Tree t new_chi] else [] bb :: [Var] -> Int -> [Assgn] bb vars n = let cons = take n $ (true : [ f a | a <- [2..]]) f a = foldl1 (&) [check a m | m <- [1..a-1]] in concatMap (cc cons) (fun vars) where fun (v:vs) = [Tree (v:=x) (fun vs) | x <- [1..n]] fun [] = [] check :: Int -> Int -> [Assignment] -> Bool check m n ass = safe (ass!!(m-1)) (ass!!(n-1)) true :: [Assignment] -> Bool true _ = True (&) :: ([Assignment]->Bool) -> ([Assignment]->Bool) -> ([Assignment]->Bool) f1 & f2 = \ints -> f1 ints && f2 ints safe :: Assignment -> Assignment -> Bool safe (i:=j) (m:=n) = unsafePerformIO $ do c <- readIORef counter writeIORef counter $! (c+1) return $ not (j==n || i+j==m+n || i-j==m-n) results :: [Assgn] -> Int -> [[Assignment]] results t no= concatMap ((filter (\l->length l == no)).flatten) t where flatten (Tree t []) = [[t]] flatten (Tree t cs) = map (t:) (concatMap flatten cs) counter :: IORef Integer counter = unsafePerformIO $ newIORef (0::Integer)

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binary package for ix86-solaris2 available
by Malcolm Wallace 10 Apr '02

10 Apr '02

Dear nhc-users, Jon Bernard has kindly made a binary package of nhc98-1.12 for Solaris 2.8 on x86 machines. It is available from the usual download page, http://www.cs.york.ac.uk/fp/nhc98/download.html Regards, Malcolm

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