The MaybeT transformer is defined as: newtype MaybeT m a = MaybeT {runMaybeT :: m (Maybe <http://haskell.org/ghc/docs/latest/html/libraries/base/Prelude.html#t:Maybe> a)} instance Functor <http://haskell.org/ghc/docs/latest/html/libraries/base/Prelude.html#t:Functor> m => Functor <http://haskell.org/ghc/docs/latest/html/libraries/base/Prelude.html#t:Functor> (MaybeT m) where fmap <http://haskell.org/ghc/docs/latest/html/libraries/base/Prelude.html#v:fmap> f x = MaybeT $ <http://haskell.org/ghc/docs/latest/html/libraries/base/Prelude.html#v:.> fmap <http://haskell.org/ghc/docs/latest/html/libraries/base/Prelude.html#v:fmap> (fmap <http://haskell.org/ghc/docs/latest/html/libraries/base/Prelude.html#v:fmap> f) $ <http://haskell.org/ghc/docs/latest/html/libraries/base/Prelude.html#v:.> runMaybeT x .... Question: What does "runMaybeT x" mean? Thanks, Daryoush