{-#Language ForeignFunctionInterface#-}
module Safe where
import Foreign.C.Types
fibonacci :: Int -> Int
fibonacci n = fibs !! n
  where fibs = 0 : 1: zipWith (+) fibs (tail fibs)
fibonacci_hs ::CInt -> CInt
fibonacci_hs = fromIntegral.fibonacci.fromIntegral
foreign export ccall fibonacci_hs::CInt->CInt