>>> unlessM (pure False) $ putTextLn "No text :(" No text :( >>> unlessM (pure True) $ putTextLn "Yes text :)"
>>> whenM (pure False) $ putTextLn "No text :(" >>> whenM (pure True) $ putTextLn "Yes text :)" Yes text :) >>> whenM (Just True) (pure ()) Just () >>> whenM (Just False) (pure ()) Just () >>> whenM Nothing (pure ()) Nothing
do as bs
as >>= const bs