From Newsgroup: comp.lang.scheme

Which means you can use LOOP:

(defun count-constraints-involvement (val list)
(loop for row in *rows*
when (and (find val row) (some (lambda (y) (find y row)) list)))
sum 1))

Or even:

(loop for row in *rows*
count (and (find val row)
(some (lambda (y) (find y row)) list)))

Gauche Scheme

(use srfi-42) ;; sum-ec
(use srfi-1) ;; lset-intersection

(define *rows* '((77 0 2 3) (88 0 2 3) (88 5 6) (88 7 8 9)))

(define (count-constraints-involvement one-val many-vals)
(sum-ec (:list row *rows*)
(if (member one-val row))
(if (pair? (lset-intersection equal? many-vals row)))
1))

(count-constraints-involvement 77 '(0 8))
===>
1

(count-constraints-involvement 88 '(0 8))
===>
2

(count-constraints-involvement 88 '(5 6))
===>
1

(count-constraints-involvement 99 '(5 6))
===>
0
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