Comment by Arguggi

This seems pretty similar to the Haskell Maybe Monad.

"Learn You a Haskell for Great Good!" has an example[0]:

  routine =   
    case Just (0,0) of   
        Nothing -> Nothing  
        Just start -> case landLeft 2 start of  
            Nothing -> Nothing  
            Just first -> case landRight 2 first of  
                Nothing -> Nothing  
                Just second -> landLeft 1 second

becomes (using some 'do' syntactic sugar):

  routine = do  
    start <- return (0,0)  
    first <- landLeft 2  
    second <- landRight 2 first  
    landLeft 1 second

Checking for Nothing is taken care of 'automatically' and if any of start, first, second or (landLeft 1 second) are equal to Nothing routine is equal to Nothing too.

[0] http://learnyouahaskell.com/a-fistful-of-monads#walk-the-lin...