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{-# LANGUAGE Trustworthy #-} {-# LANGUAGE NoImplicitPrelude #-}

-- | -- Module : Foreign.StablePtr -- Copyright : (c) The University of Glasgow 2001 -- License : BSD-style (see the file libraries/base/LICENSE)

-- Maintainer : ffi@haskell.org -- Stability : provisional -- Portability : portable

-- This module is part of the Foreign Function Interface (FFI) and will usually -- be imported via the module "Foreign".

module Foreign.StablePtr ( -- * Stable references to Haskell values StablePtr -- abstract , newStablePtr , deRefStablePtr , freeStablePtr , castStablePtrToPtr , castPtrToStablePtr , -- ** The C-side interface

      -- $cinterface
    ) where

import GHC.Stable

-- $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.