Заданное преобразование двумерного массива

[ ((Int, Int), t) ] -> Array (Int, Int) t

module ArrayX2(ArrayX2,newArrX2,getX2,putX2,maxI,maxJ,inBnds,forIO,for,foreachX2,foreachIX2) where
import Data.Array.IO
 
data ArrayX2 a = AX2 !Int !Int !(IOArray Int a)
 
for         :: a -> (a -> Bool) -> (a -> a) -> (b -> a -> b) -> b -> b
forIO       :: a -> (a -> Bool) -> (a -> a) -> (a -> IO()) -> IO()
foreachX2   :: ArrayX2 a -> (a -> IO()) -> IO()
foreachIX2  :: ArrayX2 a -> (Int -> Int -> a -> IO()) -> IO()
newArrX2    :: Int -> Int -> a -> IO (ArrayX2 a)
getX2       :: ArrayX2 a -> Int -> Int -> IO a
putX2       :: ArrayX2 a -> Int -> Int -> a -> IO()
maxI        :: ArrayX2 a -> Int
maxJ        :: ArrayX2 a -> Int
inBnds      :: ArrayX2 a -> Int -> Int -> Bool
 
newArrX2 mx my nl = newArray (0,mx * my) nl >>= return.(AX2 mx my)
 
maxI (AX2 a _ _) = a
maxJ (AX2 _ a _) = a
 
getX2 (AX2 _ mj a) i j = readArray a ((i * mj) + j)
putX2 (AX2 _ mj a) i j e = writeArray a ((i * mj) + j) e
 
inBnds (AX2 mi mj _) i j = i >= 0 && i < mi && j >= 0 && j < mj
 
{-# INLINE forIO #-}
forIO i check inc foo = if check i then foo i >> forIO (inc i) check inc foo else return()
{-# INLINE for #-}
for i check inc foo acc = if check i
                                then for (inc i) check inc foo (foo acc i)
                                else acc
 
{-# INLINE foreachX2 #-}
foreachX2 a f = forIO 0 (<maxI a) (+1) (\i -> forIO 0 (<maxJ a) (+1) (\j -> getX2 a i j >>= f))
{-# INLINE foreachIX2 #-}
foreachIX2 a f = forIO 0 (<maxI a) (+1) (\i -> forIO 0 (<maxJ a) (+1) (\j -> getX2 a i j >>= f i j))

import ArrayX2
 
list = [((1,3),5),((0,2),6),((7,7),2),((8,0),1),((1,1),3)]
 
main = do
    let mx = foldl (\a ((x,_),_) -> max a x) 0 list + 1
    let my = foldl (\a ((_,y),_) -> max a y) 0 list + 1
    arr <- newArrX2 mx my 0
    mapM_ (\((x,y),v) -> putX2 arr x y v) list
    forIO 0 (<my) (+1) $ \y -> do
        forIO 0 (<mx) (+1) $ \x -> getX2 arr x y >>= putStr.(++ " ").show
        putChar '\n'