#if __GLASGOW_HASKELL__ >= 701 {-# LANGUAGE Safe #-} #endif module Foreign.StablePtr ( -- * Stable references to Haskell values StablePtr -- abstract , newStablePtr -- :: a -> IO (StablePtr a) , deRefStablePtr -- :: StablePtr a -> IO a , freeStablePtr -- :: StablePtr a -> IO () , castStablePtrToPtr -- :: StablePtr a -> Ptr () , castPtrToStablePtr -- :: Ptr () -> StablePtr a , -- ** The C-side interface -- $cinterface ) where import "base" Foreign.StablePtr as This___ -- $cinterface -- -- The following definition is available to C programs inter-operating with -- Haskell code when including the header @HsFFI.h@. -- -- > typedef void *HsStablePtr; /* C representation of a StablePtr */ -- -- Note that no assumptions may be made about the values representing stable -- pointers. In fact, they need not even be valid memory addresses. The only -- guarantee provided is that if they are passed back to Haskell land, the -- function 'deRefStablePtr' will be able to reconstruct the -- Haskell value referred to by the stable pointer.