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+; P19 Rotate a list N places to the left.
+
+(def a (list "a" "b" "c" "d" "e" "f" "g" "h"))
+
+(func rotate (lst cnt)
+    (branch
+        ((eq? 0 cnt) lst)
+        ((> cnt 0)
+            (rotate (append (rest lst) (first lst)) (- cnt 1)))
+        ((< cnt 0)
+            (rotate (prepend (most lst) (last lst)) (+ cnt 1)))))
+
+(print (->string a))
+(print (->string (rotate a 3)))
+(print (->string (rotate a (- 2))))