[Haskell-cafe] How to simplify the code of Maybe within a monad?

[Magicloud Magiclouds]

Hi,
  Since Maybe is a monad, I could write code like 'maybeA >> maybeB >>
maybeC' to check if all these are not Nothing. Or 'liftM foo maybeD'
to avoid ugly 'case of'.
  But how if here maybe[ABC] are like 'IO (Maybe Int)', or foo is type
of 'Int -> IO Int'?
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