Newbie qustion about monads

[Derek Elkins]

>From your examples and interpretations, it looks like you need to become
more familiar and comfortable with -using- monads before you bother
trying to write one.  Then once you have that down, seeing how -correct-
monads work would probably be the next most helpful thing.  You'll have
a very hard time thinking up correct monads if you don't have any
intuition about how they are supposed to be used. In any case, knowing
how to write an instance of Monad is probably the least useful thing to
know about them in Haskell.