[project @ 1997-05-18 04:15:13 by sof]

unsafePerformPrimIO not defined in terms of runST

diff --git a/ghc/lib/ghc/STBase.lhs b/ghc/lib/ghc/STBase.lhs
index afc3d51..bdc7a65 100644 (file)
--- a/ghc/lib/ghc/STBase.lhs
+++ b/ghc/lib/ghc/STBase.lhs
@@ -54,7 +54,7 @@ returnST = return
 thenST   = (>>=)
 seqST   = (>>)
 
-unsafeInterleaveST :: ST s a -> ST s a    -- ToDo: put in state-interface.tex
+unsafeInterleaveST :: ST s a -> ST s a
 unsafeInterleaveST (ST m) = ST $ \ s ->
     let
        (r, new_s) = m s
@@ -95,9 +95,13 @@ fixPrimIO = fixST
 
 {-# GENERATE_SPECS unsafePerformPrimIO a #-}
 unsafePerformPrimIO    :: PrimIO a -> a
-unsafeInterleavePrimIO :: PrimIO a -> PrimIO a
+       -- We give a fresh definition here.  There are no
+       -- magical universal types kicking around.
+unsafePerformPrimIO (ST m)
+  = case m (S# realWorld#) of
+      (r,_) -> r
 
-unsafePerformPrimIO    = runST
+unsafeInterleavePrimIO :: PrimIO a -> PrimIO a
 unsafeInterleavePrimIO = unsafeInterleaveST
 
 -- the following functions are now there for backward compatibility mostly: