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Combining two sets: `union'

This abstraction takes two lists as arguments and creates a new list having the property of a set by ensuring that elements may not occur more than once in the resulting list.

(define union (lambda(s1 s2)
(if (nullp s1) ...
(union (cdr s1) s2)
(cons (car s1) (union (cdr s1) s2))))))

(define l1 (cons one
(cons two
(cons thre...
...! (union l1 l2))
--> 1
4 ;; kommt nur einmal vor

domain access counter Georg P. Loczewski 2004-03-05