1 files changed, 16 insertions, 0 deletions
diff --git a/lib/mill.fnl b/lib/mill.fnl
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+(local {: contains} (require :lib.contains))
+
+;; Does this move result in a mill?
+(fn mill? [rules state move]
+  (let [candidates (icollect [_ mill (ipairs rules)] (if (contains mill move) mill))
+        candidate->moves (icollect [_ spaces (ipairs candidates)]
+                                  (icollect [_ space (ipairs spaces)] (. state space)) )
+        candidate-mill? (icollect [_ moves (ipairs candidate->moves)]
+                                  (accumulate [acc true
+                                              idx m (ipairs moves)]
+                                              (and acc (not= 0 m) (= (. moves idx) m)))) ]
+    (accumulate [acc true
+                 _ x (ipairs candidate-mill?)]
+                (and acc x))))
+
+{: mill?}