1 files changed, 41 insertions, 0 deletions
diff --git a/lib/game/mill.fnl b/lib/game/mill.fnl
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+(local {: contains} (require :lib.table))
+
+(fn get-candidates [all-mills next-move]
+  "a list of mills that contain next-move"
+  (icollect [_ mill (ipairs all-mills)]
+    (if (contains mill next-move) mill)))
+
+(fn any [t]
+  "take a list of booleans, returns true if any of them are true"
+  (accumulate [acc false
+               i x (ipairs t)]
+               (or acc x)))
+
+(fn move-mills [moves-list]
+  (icollect [_ moves (ipairs moves-list)]
+    (let [player (. moves 1)]
+      (accumulate [acc true
+                   _ m (ipairs moves)]
+                  (and acc (not= m 0) (= player m))))))
+
+(fn candidate-moves [moves candidates]
+  "Just turning board spaces into player moves"
+  (icollect [_ spaces (ipairs candidates)]
+            (icollect [_ space (ipairs spaces)]
+                      (. moves space))))
+
+(fn mill-at? [all-mills current-moves move]
+  "Is there a mill at this move?"
+  (->> (get-candidates all-mills move)
+       (candidate-moves current-moves) 
+       (move-mills)
+       (any)))
+
+{: mill-at?
+ ;; not for consumption,
+ ;; just for testing:
+ : get-candidates
+ : candidate-moves
+ : move-mills
+ : any
+ }