-- Trac #3263. New kind of warning on ignored monadic bindings module T3263 where nullM :: IO () nullM = return () nonNullM :: IO Int nonNullM = return 10 -- No warning t1 = do nonNullM -- No warning t2 = nonNullM -- No warning t3 = do nullM nonNullM -- Warning t4 = do nonNullM nullM -- No warning t5 = do _ <- nonNullM nullM -- Warning t6 = mdo nonNullM nullM