(set-difference set1 set2)

Returns the elements of set1 not found in set2.

Parameter	Description
set1	Set
set2	Set

Example

> (define a (list->set '("a" "b" "c") string<?))
> (define b (list->set '("b" "g" "h") string<?))
> (set->list (set-difference a b))
("a" "c")