diff --git a/plugins/ruby/ruby-memstruct.rb b/plugins/ruby/ruby-memstruct.rb
index adde84699..cb99dbefb 100644
--- a/plugins/ruby/ruby-memstruct.rb
+++ b/plugins/ruby/ruby-memstruct.rb
@@ -303,6 +303,7 @@ module IndexEnum
 end
 module Enumerable
 	include ::Enumerable
+	attr_accessor :_indexenum
 	def each ; (0...length).each { |i| yield self[i] } ; end
 	def inspect
 		enum = DFHack.const_get(_indexenum)::ENUM if _indexenum