Should I link the result to the Monad?

Question

Below is an example from the Haskell Tutorial

instance Monad Maybe where  
    return x = Just x  
    Nothing >>= f = Nothing  
    Just x >>= f  = f x  
    fail _ = Nothing  

However, the line confuses me Just x.... Should the result not be a monad? I expect the string to be

Just x >>= f = Just (f x)

Answer 1

Yes! You are right that the result was the Monad, but keep in mind the type of operator >>=: m a -> (a -> m b) -> m b. Then we assume that it fhas a type a -> m b, so applying fto xreturns a monad as a result.