chickadee » slset » slset-diff+intersection

slset-diff+intersection LIST_1 LIST_2 ...procedure

Returns two values -- the difference and the intersection of the lists. Is equivalent to

(values (slset-difference LIST_1 LIST_2 ...)
        (slset-intersection LIST_1
                            (lset-union = LIST_2 ...)))

but can be implemented more efficiently.

Either of the answer lists may share a common tail with LIST_1. This operation essentially partitions LIST_1.