Make -dppr-debug print locations in HsSyn

[ghc-hetmet.git] / compiler / utils / Util.lhs

diff --git a/compiler/utils/Util.lhs b/compiler/utils/Util.lhs
index 3de52b6..37aedc8 100644 (file)
--- a/compiler/utils/Util.lhs
+++ b/compiler/utils/Util.lhs
@@ -65,7 +65,7 @@ module Util (
         doesDirNameExist,
         modificationTimeIfExists,
 
-        global, consIORef,
+        global, consIORef, globalMVar, globalEmptyMVar,
 
         -- * Filenames and paths
         Suffix,
@@ -83,6 +83,7 @@ import Data.IORef       ( IORef, newIORef )
 import System.IO.Unsafe ( unsafePerformIO )
 import Data.IORef       ( readIORef, writeIORef )
 import Data.List        hiding (group)
+import Control.Concurrent.MVar ( MVar, newMVar, newEmptyMVar )
 
 #ifdef DEBUG
 import qualified Data.List as List ( elem, notElem )
@@ -522,7 +523,7 @@ sortWith get_key xs = sortLe le xs
   where
     x `le` y = get_key x < get_key y
 
-on :: (a -> a -> Ordering) -> (b -> a) -> b -> b -> Ordering
+on :: (a -> a -> c) -> (b -> a) -> b -> b -> c
 on cmp sel = \x y -> sel x `cmp` sel y
 
 \end{code}
@@ -699,6 +700,14 @@ consIORef var x = do
   writeIORef var (x:xs)
 \end{code}
 
+\begin{code}
+globalMVar :: a -> MVar a
+globalMVar a = unsafePerformIO (newMVar a)
+
+globalEmptyMVar :: MVar a
+globalEmptyMVar = unsafePerformIO newEmptyMVar
+\end{code}
+
 Module names:
 
 \begin{code}