MicroHs-0.15.0.0: tests/ForeignPtr.hs

module ForeignPtr(main) where
import System.Mem
import Foreign.Ptr
import Foreign.ForeignPtr
import Foreign.Storable

add :: Ptr a -> Int -> Ptr a
add = plusPtr

sInt :: Int
sInt = sizeOf (0::Int)

main :: IO ()
main = do
  fp <- mallocForeignPtrArray 2
  withForeignPtr fp $ \ p -> do
    poke p (42::Int)
    poke (add p sInt) (88::Int)
  withForeignPtr fp $ \ p -> do
    performGC
    peek p >>= print
    peek (add p sInt) >>= print
  let fp1 :: ForeignPtr Int
      fp1 = plusForeignPtr fp sInt
  withForeignPtr fp1 $ \ p -> do
    peek p >>= print
  performGC