liftMaybe is:exact
Lift a Maybe value into the Unpickler monad.
The 1. arg is the attached error message
Lift a maybe into the
Fail effect, causing failure if it's
Nothing.
Construct an
SMaybe a from a
Maybe (SBV a).
>>> liftMaybe (Just (3 :: SInteger))
Just 3 :: SMaybe Integer
>>> liftMaybe (Nothing :: Maybe SInteger)
Nothing :: SMaybe Integer
Lift a maybe to an Alternative.
Lift a
Maybe value into the
MaybeT monad transformer.
Translate a maybe value into wizard success/failure.