import Data.Char
import Foreign
-- import System.IO

f589_1 :: IO ()
f589_1 = do
    a <- addr (12 :: Int)
    p_a <- addr a
    b <- addr (3.45 :: Float)
    p_b <- addr b
    prn "a" a
    prn "p_a" p_a
    prn "b" b
    prn "p_b" p_b
    free a >> free p_a >> free b >> free p_b
    where
      addr a = malloc >>= \p -> poke p a >> return p
      prn x i = do
          v <- peek i
          putStrLn $ x ++ "のアドレスは、" ++ show i
          putStrLn $ x ++ "の値は、" ++ show v

f589_2 :: IO ()
f589_2 = do
    let c = 'A'
    p <- malloc
    poke p c
    peek p >>= putStrLn . (:[])
    peek p >>= poke p . chr . (+2) . ord
    peek p >>= putStrLn . (:[])
    free p

main :: IO ()
main = -- hSetEncoding stdout utf8 >>
       f589_1 >> f589_2