comments for Main.hs, add io_, like io but return ()

darcs-hash:20070307032139-9c5c1-b063c7a18960d67fabf03d42b6b9d01a855c9cf5

1 files changed, 9 insertions, 0 deletions

diff --git a/Wm.hs b/Wm.hs
index c95648d..6b30ac1 100644
--- a/Wm.hs
+++ b/Wm.hs
@@ -33,9 +33,18 @@ newtype Wm a = Wm (StateT WmState IO a)
 runWm :: Wm a -> WmState -> IO (a, WmState)
 runWm (Wm m) = runStateT m
 
+--
+-- | Lift an IO action into the Wm monad
+--
 io :: IO a -> Wm a
 io = liftIO
 
+--
+-- | Lift an IO action into the Wm monad, discarding any result
+--
+io_ :: IO a -> Wm ()
+io_ f = liftIO f >> return ()
+
 trace msg = io $ do
     hPutStrLn stderr msg
     hFlush stderr