{-# 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".-------------------------------------------------------------------------------moduleForeign.StablePtr(-- * Stable references to Haskell valuesStablePtr -- abstract,newStablePtr ,deRefStablePtr ,freeStablePtr ,castStablePtrToPtr ,castPtrToStablePtr ,-- ** The C-side interface-- $cinterface)whereimportGHC.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.