Sunil.

On Thu, Aug 11, 2011 at 4:23 PM, Sunil S Nandihalli <sunil.nandihalli@gmail.com> wrote:

Hello everybody,
When I compile a file containing ...

plotAsString::(Integral a)=>[(a,a)]->a->String

plotAsString locs ans = let xs = map fst locs
   ys = map snd locs

   locsmap = M.fromList (zip locs [0..])
   bufsize=10
   min' = ((\x -> x-bufsize) . minimum)
   max' = ((\x -> x+bufsize) . maximum)

   (bmin@(x0,y0),bmax@(x1,y1)) = ((min' xs,min' ys),(max' xs,max' ys))
   plotString = foldl (\curStr newRowId -> (foldl (\ccStr newColId -> (ccStr++(case (M.member (newRowId,newColId) locsmap) of

   (Just v) -> ("." ++ (show v) ++ ".")
   (Nothing) -> " ")))

   curStr [y0..y1])) "" [x0..x1]
   in plotString

I get the following error..

main.hs:34:107:
   Couldn't match expected type `Bool' with actual type `Maybe t0'
   In the pattern: Just v
   In a case alternative: (Just v) -> ("." ++ (show v) ++ ".")

   In the second argument of `(++)', namely
   `(case (M.member (newRowId, newColId) locsmap) of {
   (Just v) -> ("." ++ (show v) ++ ".")
   (Nothing) -> " " })'

can somebody help?

Thanks,
Sunil.