This code appears to be equivalent to using Maybe in Haskell, with the
same kind of indentation issues:
case char-width of
Nothing -> Nothing
Just n -> do stuff, get new Maybe, case new-maybe of
Nothing -> Nothing
Just x -> do stuff ... etc...
In Haskell, one composes these with bind, which combines the "do stuff"
portion with the unwrapped Just value, otherwise continues returning
false forever (which due to laziness is the same as the first cond
returning #f).
In Racket, one could implement either monads altogether or specifically
one to handle chaining functions that might return #f.
e.g., instead of cond:
(maybe
(do something)
(bind new possibly false value)
(do something with that value)
etc.)
____________________
Racket Users list:
http://lists.racket-lang.org/users
