treak

Utility/Monad.hs

@@ -12,7 +12,7 @@ import Control.Monad (liftM)
 
 {- Return the first value from a list, if any, satisfying the given
  - predicate -}
-firstM :: (Monad m) => (a -> m Bool) -> [a] -> m (Maybe a)
+firstM :: Monad m => (a -> m Bool) -> [a] -> m (Maybe a)
 firstM _ [] = return Nothing
 firstM p (x:xs) = do
 	q <- p x
@@ -22,20 +22,20 @@ firstM p (x:xs) = do
 
 {- Returns true if any value in the list satisfies the predicate,
  - stopping once one is found. -}
-anyM :: (Monad m) => (a -> m Bool) -> [a] -> m Bool
+anyM :: Monad m => (a -> m Bool) -> [a] -> m Bool
 anyM p = liftM isJust . firstM p
 
 {- Runs an action on values from a list until it succeeds. -}
-untilTrue :: (Monad m) => [a] -> (a -> m Bool) -> m Bool
+untilTrue :: Monad m => [a] -> (a -> m Bool) -> m Bool
 untilTrue = flip anyM
 
 {- Runs an action, passing its value to an observer before returning it. -}
-observe :: (Monad m) => (a -> m b) -> m a -> m a
+observe :: Monad m => (a -> m b) -> m a -> m a
 observe observer a = do
 	r <- a
 	_ <- observer r
 	return r
 
 {- b `after` a runs first a, then b, and returns the value of a -}
-after :: (Monad m) => m b -> m a -> m a
+after :: Monad m => m b -> m a -> m a
 after = observe . const