ArrayRef-0.1: Examples/SyntaxSugar.hs

-- This module demonstrates using of syntax sugar when manipulating
--   references, arrays and hash tables, including implementation
--   of monad-independent algorithms with references
import Control.Monad.ST
import Data.SyntaxSugar
import Data.Ref
import Data.ArrayBZ.IO
import Data.HashTable as Hash

main = do
          -- This section demonstrates running of monad-independent
          -- algorithm that use boxed references in IO and ST monads
          test_Ref 5            >>= print
          runST (test_Ref 6)    |>  print

          -- This section demonstrates running of monad-independent
          -- algorithm that use unboxed references in IO and ST monads
          test_URef 7           >>= print
          runST (test_URef 8)   |>  print

          -- Using syntax sugar with arrays
          test_Array            >>= print

          -- Using syntax sugar with hash tables
          test_Hash             >>= print


-- Monad-independent computation that uses boxed reference
test_Ref init = do
          x <- ref (0::Int)
          x =: init
          x += 10
          x -= 2
          x .= (*2)
          val x

-- Monad-independent computation that uses unboxed reference
test_URef init = do
          x <- uref (0::Int)
          x =: init
          x += 10
          x -= 2
          x .= (*2)
          val x

-- Using syntax sugar with arrays
test_Array = do
          let i = 0::Int

          arr <- newArray (0,9) 0 :: IO (IOArray Int Double)
          (arr,i) =: 1
          (arr,i) += 10
          (arr,i) -= 2
          (arr,i) .= (*2)
          x <- val (arr,i)

          arr2 <- newArray ((0,0), (9,9)) 0 :: IO (IOArray (Int,Int) Double)
          (arr2,i,i) =: 1
          (arr2,i,i) += 10
          (arr2,i,i) -= 2
          (arr2,i,i) .= (*2)
          y <- val (arr2,i,i)

          return (x,y)


-- Using syntax sugar with hash tables
test_Hash = do
          let key = "test"
          hash <- Hash.new (==) hashString
          (hash,key) =: 1
          (hash,key) += 10
          (hash,key) -= 2
          (hash,key) .= (*2)
          val (hash,key)


-- Helper operations
a |> b = b a
for list action = mapM_ action list