diff options
Diffstat (limited to 'Utility/Monad.hs')
| -rw-r--r-- | Utility/Monad.hs | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/Utility/Monad.hs b/Utility/Monad.hs index 9e2a16e8c..7f9c7b1bc 100644 --- a/Utility/Monad.hs +++ b/Utility/Monad.hs @@ -36,3 +36,7 @@ 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) |