yes

csp/csp/hacs-map.rkt

@@ -2,7 +2,6 @@
 (require "hacs.rkt" sugar/debug)
 (module+ test (require rackunit))
 
-
 (define (map-coloring-csp colors neighbors)
   (define names (remove-duplicates (flatten neighbors) eq?))
   (define vds (for/list ([name (in-list names)])

csp/csp/hacs.rkt

@@ -15,7 +15,7 @@
                   (let loop ([argss argss][acc empty])
                     (if (null? argss)
                         (yield (reverse acc))
-                        (for ([arg (in-list (car argss))])
+                        (for ([arg (car argss)])
                           (loop (cdr argss) (cons arg acc))))))))
 
 (struct csp (vars constraints [assignments #:auto] [checks #:auto])
@@ -74,9 +74,9 @@
   ((csp? (or/c (listof name?) procedure?)) ((or/c (listof any/c) procedure?)) . ->* . void?)
   (for/fold ([vrs (vars prob)]
              #:result (set-csp-vars! prob vrs))
-            ([name (in-list (if (procedure? names-or-procedure)
-                                (names-or-procedure)
-                                names-or-procedure))])
+            ([name (in-list (match names-or-procedure
+                              [(? procedure? proc) (proc)]
+                              [names names]))])
     (when (memq name (map var-name vrs))
       (raise-argument-error 'add-vars! "var that doesn't already exist" name))
     (append vrs (list (var name
@@ -200,11 +200,15 @@
 
 (define (reset-nfcs!) (set! nfchecks 0))
 
+(define nchecks 0)
+
+(define (reset-nchecks!) (set! nchecks 0))
+
 (define/contract (assign-val prob name val)
   (csp? name? any/c . -> . csp?)
   (when-debug (set! nassns (add1 nassns)))
   (make-csp
-   (for/list ([vr (vars prob)])
+   (for/list ([vr (in-vars prob)])
      (if (eq? name (var-name vr))
          (assigned-var name (list val))
          vr))
@@ -278,14 +282,14 @@
 (define/contract (forward-check prob ref-name)
   (csp? name? . -> . csp?)
   (define aval (first (find-domain prob ref-name)))
-  (define (check-var v)
-    (match v
+  (define (check-var vr)
+    (match vr
       ;; don't check against assigned vars, or the reference var
       ;; (which is probably assigned but maybe not)
-      [(? (λ (x) (or (assigned-var? x) (eq? (var-name x) ref-name)))) v]
+      [(? (λ (x) (or (assigned-var? x) (eq? (var-name x) ref-name)))) vr]
       [(var name vals)
        (match ((constraints prob) . relating-only . (list ref-name name))
-         [(? empty?) v]
+         [(? empty?) vr]
          [constraints
           (define new-vals
             (for/list ([val (in-list vals)]
@@ -295,15 +299,15 @@
                                       (proc val aval)
                                       (proc aval val)))))
               val))
-          (checked-variable name new-vals (cons ref-name (match v
+          (checked-variable name new-vals (cons ref-name (match vr
                                                            [(checked-variable _ _ history) history]
                                                            [else null])))])]))
   (define checked-vars (map check-var (vars prob)))
   (when-debug (set! nfchecks (+ (length checked-vars) nchecks)))
   ;; conflict-set will be empty if there are no empty domains (as we would hope)
-  (define conflict-set (for*/list ([cv (in-list checked-vars)]
-                                   #:when (empty? (domain cv))
-                                   [name (in-list (history cv))])
+  (define conflict-set (for*/list ([cvr (in-list checked-vars)]
+                                   #:when (empty? (domain cvr))
+                                   [name (in-list (history cvr))])
                          name))
   ;; for conflict-directed backjumping it's essential to forward-check ALL vars
   ;; (even after an empty domain is generated) and combine their conflicts
@@ -337,8 +341,6 @@
 (define (singleton-var? var)
   (= 1 (domain-length var)))
 
-(define nchecks 0)
-(define (reset-nchecks!) (set! nchecks 0))
 (define/contract (check-constraints prob [mandatory-names #f] #:conflicts [conflict-count? #f])
   ((csp?) ((listof name?) #:conflicts boolean?) . ->* . (or/c csp? natural?))
   ;; this time, we're not limited to assigned variables
@@ -491,17 +493,6 @@
    (apply append (map vars probs))
    (apply append (map csp-constraints probs))))
 
-(define/contract (make-cartesian-generator solgens)
-  ((listof generator?) . -> . generator?)
-  (generator ()
-             (define solstreams (for/list ([solgen (in-list solgens)])
-                                          (for/stream ([sol (in-producer solgen (void))]) 
-                                                      sol))) 
-             (let loop ([solstreams solstreams][sols empty])
-               (if (null? solstreams)
-                   (yield (combine-csps (reverse sols)))
-                   (for ([sol (in-stream (car solstreams))])
-                        (loop (cdr solstreams) (cons sol sols)))))))
 
 (define/contract (extract-subcsp prob names)
   (csp? (listof name?) . -> . csp?)
@@ -528,9 +519,14 @@
           (extract-subcsp prob nodeset))
         (list prob)))
 
-  (for/list ([solution (in-producer (make-cartesian-generator (map solver subcsps)) (void))]
+  (define solgens (map solver subcsps))
+  (define solstreams (for/list ([solgen (in-list solgens)])
+                       (for/stream ([sol (in-producer solgen (void))]) 
+                         sol)))
+  
+  (for/list ([solution-pieces (in-cartesian solstreams)]
              [idx (in-range max-solutions)])
-            (finish-proc solution)))
+    (finish-proc (combine-csps solution-pieces))))
 
 (define/contract (solve prob
                         #:finish-proc [finish-proc csp->assocs]