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  1. import Data.Char
  2. import Foreign
  3. -- import System.IO
  4.  
  5. f589_1 :: IO ()
  6. f589_1 = do
  7.     a <- addr (12 :: Int)
  8.     p_a <- addr a
  9.     b <- addr (3.45 :: Float)
  10.     p_b <- addr b
  11.     prn "a" a
  12.     prn "p_a" p_a
  13.     prn "b" b
  14.     prn "p_b" p_b
  15.     free a >> free p_a >> free b >> free p_b
  16.     where
  17.       addr a = malloc >>= \p -> poke p a >> return p
  18.       prn x i = do
  19.           v <- peek i
  20.           putStrLn $ x ++ "のアドレスは、" ++ show i
  21.           putStrLn $ x ++ "の値は、" ++ show v
  22.  
  23. f589_2 :: IO ()
  24. f589_2 = do
  25.     let c = 'A'
  26.     p <- malloc
  27.     poke p c
  28.     peek p >>= putStrLn . (:[])
  29.     peek p >>= poke p . chr . (+2) . ord
  30.     peek p >>= putStrLn . (:[])
  31.     free p
  32.  
  33. main :: IO ()
  34. main = -- hSetEncoding stdout utf8 >>
  35.        f589_1 >> f589_2
  36.  
Success #stdin #stdout 0s 6324KB
comments (?)
stdin 
Standard input is empty
stdout 
aのアドレスは、0x09090758
aの値は、12
p_aのアドレスは、0x09090768
p_aの値は、0x09090758
bのアドレスは、0x09090778
bの値は、3.45
p_bのアドレスは、0x09090788
p_bの値は、0x09090778
A
C
https://ideone.com/l2Wyc0
language:
Haskell (ghc 8.4.4)
created:
10 years ago
visibility:
secret

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