1 files changed, 16 insertions, 0 deletions
diff --git a/algebraic-structures.group.scm b/algebraic-structures.group.scm
new file mode 100644
index 0000000..6e38eaf
--- /dev/null
+++ b/algebraic-structures.group.scm
@@ -0,0 +1,16 @@
+(functor ((algebraic-structures group) (M (<> unit inv)))
+    (<> unit inv pow)
+  (import M
+          scheme
+          (chicken base))
+
+  (define (pow x n)
+    (assert (exact-integer? n))
+    (if (negative? n)
+        (pow (inv x) (- n))
+        (let loop ((i n)
+                   (acc unit))
+          (if (= i 0)
+              acc
+              (loop (sub1 i)
+                    (<> acc x)))))))