lib/map/struct.rb in map-1.5.0 vs lib/map/struct.rb in map-1.5.1

@@ -1,7 +1,7 @@
 class Map
   class Struct
-    instance_methods.each { |m| undef_method m unless m =~ /^__/ }
+    instance_methods.each { |m| undef_method m unless m =~ /^__|object_id/ }
 
     attr :map
 
     def initialize(map)
       @map = map