keep local changes re printing circular lists

object.py

@@ -608,11 +608,11 @@ class Pair(Object):
         return "#<{n}:{s}>".format(n=self.__class__.__name__, s=self)
     def __repr__(self, obset=None):
         if obset is None:
-            # print("start anew with pair", id(self))
+            print("start anew with pair", id(self))
             obset = set()
-        # if self in obset:
-        #     # print("already seen pair", id(self))
-        #     return "<...>"
+        if self in obset:
+            print("already seen pair", id(self))
+            return "<...>"
         obset.add(self)
         result = ["("]
         current = self

tests.l

@@ -832,9 +832,9 @@
       ((x 1 x 3) . (1 x 3)))
 
 (setf b '(3 4 5 6 7))
-;; (test incf0 (progn (incf (car b) 2)
-;;                    b)
-;;       (5 4 5 6 7))
+(test incf0 (progn (incf (car b) 2)
+                   b)
+      (5 4 5 6 7))
 
 ;; (test decf0 (progn (decf (cddr b))
 ;;                    b)