From 162302d50ac611f0b709e310faa72c0e40f6de0b Mon Sep 17 00:00:00 2001 From: Matthew Butterick Date: Tue, 16 Oct 2018 13:36:28 -0700 Subject: [PATCH] work variadic --- csp/aima.rkt | 23 ++++++++++++++++------- 1 file changed, 16 insertions(+), 7 deletions(-) diff --git a/csp/aima.rkt b/csp/aima.rkt index cace3e26..89668ee0 100644 --- a/csp/aima.rkt +++ b/csp/aima.rkt @@ -48,15 +48,19 @@ (define nassigns $csp-nassigns) (define nchecks $csp-nchecks) -(define/contract (check-constraint csp A a B b) +(define/contract (check-constraint csp . varvals) ($csp? variable? any/c variable? any/c . -> . any/c) - (define AB-constraints (for/list ([constraint (in-list ($csp-constraints csp))] - #:when (for/and ([name (in-list (list A B))]) - (memq name ($constraint-names constraint)))) - constraint)) + (define varval-hash (apply hasheq varvals)) + (define relevant-constraints + (for/list ([constraint (in-list ($csp-constraints csp))] + #:when (for/and ([name (in-list (hash-keys varval-hash))]) + (memq name ($constraint-names constraint)))) + constraint)) (begin0 - (for/and ([constraint (in-list AB-constraints)]) - (($constraint-proc constraint) a b)) + (for/and ([constraint (in-list relevant-constraints)]) + (define vals (for/list ([cname (in-list ($constraint-names constraint))]) + (hash-ref varval-hash cname))) + (apply ($constraint-proc constraint) vals)) (set-$csp-nchecks! csp (add1 ($csp-nchecks csp))))) (define/contract (reset-counters! csp) @@ -494,3 +498,8 @@ (solve csp) (make-hasheq '((nsw . red) (nt . red) (q . green) (sa . blue) (t . red) (v . green) (wa . green)))) (check-equal? (begin0 (list ($csp-nassigns csp) ($csp-nchecks csp)) (reset-counters! csp)) '(9 220))) + +(solve (make-csp (list ($vd 'a '(1 2 3)) + ($vd 'b '(4 5 6)) + ($vd 'c '(7 8 9))) + (list ($constraint '(a b c) (λ (a b c) (= (+ a b c) 18)))))) \ No newline at end of file