lib/dydx/helper.rb in dydx-0.0.8 vs lib/dydx/helper.rb in dydx-0.0.9

@@ -132,7 +132,13 @@
     end
 
     def formula?(operator)
       is_a?(Formula) && (@operator == operator)
     end
+
+    Symbol.class_eval do
+      def commutative?
+        [:+, :*].include?(self)
+      end
+    end
   end
 end