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{-# LANGUAGE Safe #-}
{-# LANGUAGE ForeignFunctionInterface #-}
-- | Make sure FFI must be IO type
module Main where
import Foreign.C
foreign import ccall "SafeLang08_A" c_sin :: CDouble -> CDouble
sinx :: Double -> Double
sinx d = realToFrac $ c_sin $ realToFrac d
x :: Double
x = 0.8932
main :: IO ()
main = do
putStrLn "Hello World"
putStrLn $ "Sin of " ++ (show x) ++ " is " ++ (show $ sinx x)
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