X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Flib%2Fstd%2FRandom.lhs;h=1f19b201bf2dbaf07796b5e4f04c5a487ba7f428;hb=239e9471e104fd88ec93bf42623c3a68a496657a;hp=4a2a88d263fe7f00bdf46bbf9a7e12672d60d87a;hpb=716d91c23d0f9a62474098d32eb6237ebe755944;p=ghc-hetmet.git

diff --git a/ghc/lib/std/Random.lhs b/ghc/lib/std/Random.lhs
index 4a2a88d..1f19b20 100644
--- a/ghc/lib/std/Random.lhs
+++ b/ghc/lib/std/Random.lhs
@@ -1,7 +1,10 @@
+% ------------------------------------------------------------------------------
+% $Id: Random.lhs,v 1.25 2001/08/29 10:49:28 simonmar Exp $
 %
-% (c) The GRASP/AQUA Project, Glasgow University, 1995-99
+% (c) The University of Glasgow, 1995-2000
 %
 
+\section[Random]{Module @Random@}
 
 The June 1988 (v31 #6) issue of the Communications of the ACM has an
 article by Pierre L'Ecuyer called, "Efficient and Portable Combined
@@ -16,7 +19,7 @@ world..
 \begin{code}
 module Random
 	(
-	  RandomGen(next, split)
+	  RandomGen(next, split, genRange)
 	, StdGen
 	, mkStdGen
 	, Random ( random,   randomR,
@@ -30,17 +33,13 @@ module Random
 
 #ifndef __HUGS__
 import PrelGHC		( RealWorld )
-import PrelNum		( fromInt )
 import PrelShow		( showSignedInt, showSpace )
 import PrelRead		( readDec )
 import PrelIOBase	( unsafePerformIO, stToIO )
 import PrelArr		( STRef, newSTRef, readSTRef, writeSTRef )
-import PrelReal		( toInt )
-import PrelFloat	( float2Double, double2Float )
 import Time		( getClockTime, ClockTime(..) )
 #else
-import privileged Prelude
-			( IORef
+import PrelPrim		( IORef
 			, newIORef
 			, readIORef
 			, writeIORef
@@ -54,12 +53,14 @@ import Char		( isSpace, chr, ord )
 
 \begin{code}
 class RandomGen g where
-   next  :: g -> (Int, g)
-   split :: g -> (g, g)
+   next     :: g -> (Int, g)
+   split    :: g -> (g, g)
+   genRange :: g -> (Int,Int)
+
+   -- default mathod
+   genRange g = (minBound,maxBound)
 
-\end{code}
 
-\begin{code}
 data StdGen 
  = StdGen Int Int
 
@@ -114,7 +115,7 @@ mkStdGen s
 createStdGen :: Integer -> StdGen
 createStdGen s
  | s < 0     = createStdGen (-s)
- | otherwise = StdGen (toInt (s1+1)) (toInt (s2+1))
+ | otherwise = StdGen (fromInteger (s1+1)) (fromInteger (s2+1))
       where
 	(q, s1) = s `divMod` 2147483562
 	s2      = q `mod` 2147483398
@@ -175,17 +176,9 @@ instance Random Double where
   random g       = randomR (0::Double,1) g
   
 -- hah, so you thought you were saving cycles by using Float?
-
-#ifdef __HUGS__
 instance Random Float where
   random g        = randomIvalDouble (0::Double,1) realToFrac g
   randomR (a,b) g = randomIvalDouble (realToFrac a, realToFrac b) realToFrac g
-#else
-instance Random Float where
-  randomR (a,b) g = randomIvalDouble (float2Double a, float2Double b) double2Float g
-  random g        = randomIvalDouble (0::Double,1) double2Float g
-#endif
-
 \end{code}
 
 
@@ -217,7 +210,7 @@ randomIvalInteger (l,h) rng
           let
 	   (x,g')   = next g
 	  in
-	  f (n-1) (fromInt x + acc * b) g'
+	  f (n-1) (fromIntegral x + acc * b) g'
 
 randomIvalDouble :: (RandomGen g, Fractional a) => (Double, Double) -> (Double -> a) -> g -> (a, g)
 randomIvalDouble (l,h) fromDouble rng