Partially improve the cabalisation

Language/Hi/FastMutInt.hs

@@ -0,0 +1,81 @@
+{-# OPTIONS -cpp -fglasgow-exts #-}
+{-# OPTIONS -fno-warn-name-shadowing #-}
+-- 
+-- Copyright (C) 2004 Don Stewart - http://www.cse.unsw.edu.au/~dons
+-- 
+-- This library is free software; you can redistribute it and/or
+-- modify it under the terms of the GNU Lesser General Public
+-- License as published by the Free Software Foundation; either
+-- version 2.1 of the License, or (at your option) any later version.
+-- 
+-- This library is distributed in the hope that it will be useful,
+-- but WITHOUT ANY WARRANTY; without even the implied warranty of
+-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+-- Lesser General Public License for more details.
+-- 
+-- You should have received a copy of the GNU Lesser General Public
+-- License along with this library; if not, write to the Free Software
+-- Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
+-- USA
+--
+-- Based on code from $fptools/ghc/compiler/utils/FastMutInt.lhs
+--
+-- (c) Copyright 2002, The University Court of the University of Glasgow. 
+
+--
+-- Unboxed mutable Ints
+--
+
+module Language.Hi.FastMutInt (
+        FastMutInt, 
+        newFastMutInt,
+        readFastMutInt, 
+        writeFastMutInt,
+        incFastMutInt, 
+        incFastMutIntBy
+    ) where
+
+#include "MachDeps.h"
+
+#if __GLASGOW_HASKELL__ < 503
+import GlaExts
+import PrelIOBase
+#else
+import GHC.Base
+import GHC.IOBase
+#endif
+
+#if __GLASGOW_HASKELL__ < 411
+newByteArray# = newCharArray#
+#endif
+
+data FastMutInt = FastMutInt (MutableByteArray# RealWorld)
+
+newFastMutInt :: IO FastMutInt
+newFastMutInt = IO $ \s ->
+  case newByteArray# size s of { (# s, arr #) ->
+  (# s, FastMutInt arr #) }
+  where I# size = SIZEOF_HSINT
+
+readFastMutInt :: FastMutInt -> IO Int
+readFastMutInt (FastMutInt arr) = IO $ \s ->
+  case readIntArray# arr 0# s of { (# s, i #) ->
+  (# s, I# i #) }
+
+writeFastMutInt :: FastMutInt -> Int -> IO ()
+writeFastMutInt (FastMutInt arr) (I# i) = IO $ \s ->
+  case writeIntArray# arr 0# i s of { s ->
+  (# s, () #) }
+
+incFastMutInt :: FastMutInt -> IO Int	-- Returns original value
+incFastMutInt (FastMutInt arr) = IO $ \s ->
+  case readIntArray# arr 0# s of { (# s, i #) ->
+  case writeIntArray# arr 0# (i +# 1#) s of { s ->
+  (# s, I# i #) } }
+
+incFastMutIntBy :: FastMutInt -> Int -> IO Int	-- Returns original value
+incFastMutIntBy (FastMutInt arr) (I# n) = IO $ \s ->
+  case readIntArray# arr 0# s of { (# s, i #) ->
+  case writeIntArray# arr 0# (i +# n) s of { s ->
+  (# s, I# i #) } }
+