blob: 29918c5a61148dde753e3d0af51475ac9a47c288 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
|
-----------------------------------------------------------------------------
-- |
-- Module : System.Mem.StableName
-- Copyright : (c) The University of Glasgow 2001
-- License : BSD-style (see the file libraries/base/LICENSE)
--
-- Maintainer : libraries@haskell.org
-- Stability : experimental
-- Portability : non-portable
--
-- Giving an object a stable (GC-invariant) name.
--
-----------------------------------------------------------------------------
module System.Mem.StableName
( StableName {-a-} -- abstract, instance of Eq
, makeStableName -- :: a -> IO (StableName a)
, hashStableName -- :: StableName a -> Int
) where
import Prelude
import Data.Dynamic
#ifdef __GLASGOW_HASKELL__
import GHC.IOBase ( IO(..) )
import GHC.Base ( Int(..), StableName#, makeStableName#
, eqStableName#, stableNameToInt# )
-----------------------------------------------------------------------------
-- Stable Names
data StableName a = StableName (StableName# a)
makeStableName :: a -> IO (StableName a)
#if defined(__PARALLEL_HASKELL__)
makeStableName a =
error "makeStableName not implemented in parallel Haskell"
#else
makeStableName a = IO $ \ s ->
case makeStableName# a s of (# s', sn #) -> (# s', StableName sn #)
#endif
hashStableName :: StableName a -> Int
#if defined(__PARALLEL_HASKELL__)
hashStableName (StableName sn) =
error "hashStableName not implemented in parallel Haskell"
#else
hashStableName (StableName sn) = I# (stableNameToInt# sn)
#endif
instance Eq (StableName a) where
#if defined(__PARALLEL_HASKELL__)
(StableName sn1) == (StableName sn2) =
error "eqStableName not implemented in parallel Haskell"
#else
(StableName sn1) == (StableName sn2) =
case eqStableName# sn1 sn2 of
0# -> False
_ -> True
#endif
#endif /* __GLASGOW_HASKELL__ */
#include "Dynamic.h"
INSTANCE_TYPEABLE1(StableName,stableNameTc,"StableName")
|
