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authorGravatar Joey Hess <joey@kitenet.net>2012-01-03 00:29:27 -0400
committerGravatar Joey Hess <joey@kitenet.net>2012-01-03 00:29:27 -0400
commitee554542c1f3ee63efe5533267cf9cd1e5c83d52 (patch)
treec5378041794d4a7faad6316e915cffb804e153d2 /Utility/Monad.hs
parent34abd7bca80a8cc012f92d64116014449b1b2392 (diff)
after is a better name for observe_
Diffstat (limited to 'Utility/Monad.hs')
-rw-r--r--Utility/Monad.hs9
1 files changed, 4 insertions, 5 deletions
diff --git a/Utility/Monad.hs b/Utility/Monad.hs
index 7f9c7b1bc..be48072cb 100644
--- a/Utility/Monad.hs
+++ b/Utility/Monad.hs
@@ -29,14 +29,13 @@ anyM p = liftM isJust . firstM p
untilTrue :: (Monad m) => [a] -> (a -> m Bool) -> m Bool
untilTrue = flip anyM
-{- Runs a monadic action, passing its value to an observer
- - before returning it. -}
+{- 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
r <- a
_ <- observer r
return r
-{- Like observe, but the observer is not passed the value. -}
-observe_ :: (Monad m) => m b -> m a -> m a
-observe_ observer = observe (const observer)
+{- b `after` a runs first a, then b, and returns the value of a -}
+after :: (Monad m) => m b -> m a -> m a
+after = observe . const