thanks, think I'm starting to see, so with one sort of Monad I can chain a bunch of functions together and carry along things like an error value (or a null), a

thanks, think I'm starting to see, so with one sort of Monad I can chain a bunch of functions together and carry along things like an error value (or a null), and just skip out of the chain if an error occurs but without worrying about a bunch of if tests. That seems useful :-). The do syntax makes the chaining a lot more friendly than in other languages.