types : string -> (string * int) list
- load "bossLib";
> val it = () : unit
- itlist union (map types (ancestry "-")) [];
> val it =
[("one", 0), ("option", 1), ("prod", 2), ("sum", 2),
("fun", 2), ("ind", 0), ("bool", 0), ("num", 0),
("recspace", 1), ("list", 1)] : (string * int) list