added ifM and nuked 11 lines of code

no behavior changes

1 files changed, 8 insertions, 6 deletions

diff --git a/Utility/Monad.hs b/Utility/Monad.hs
index 28aa33ee8..23c0c4c19 100644
--- a/Utility/Monad.hs
+++ b/Utility/Monad.hs
@@ -1,6 +1,6 @@
 {- monadic stuff
  -
- - Copyright 2010-2011 Joey Hess <joey@kitenet.net>
+ - Copyright 2010-2012 Joey Hess <joey@kitenet.net>
  -
  - Licensed under the GNU GPL version 3 or higher.
  -}
@@ -14,11 +14,7 @@ import Control.Monad (liftM)
  - predicate -}
 firstM :: Monad m => (a -> m Bool) -> [a] -> m (Maybe a)
 firstM _ [] = return Nothing
-firstM p (x:xs) = do
-	q <- p x
-	if q
-		then return (Just x)
-		else firstM p xs
+firstM p (x:xs) = ifM (p x) (return $ Just x , firstM p xs)
 
 {- Returns true if any value in the list satisfies the predicate,
  - stopping once one is found. -}
@@ -29,6 +25,12 @@ anyM p = liftM isJust . firstM p
 untilTrue :: Monad m => [a] -> (a -> m Bool) -> m Bool
 untilTrue = flip anyM
 
+{- if with a monadic conditional. -}
+ifM :: Monad m => m Bool -> (m a, m a) -> m a
+ifM cond (thenclause, elseclause) = do
+	c <- cond
+	if c then thenclause else elseclause
+
 {- Runs an action, passing its value to an observer before returning it. -}
 observe :: Monad m => (a -> m b) -> m a -> m a
 observe observer a = do