diff --git a/TODO b/TODO
index 62a1eb5..4683f6c 100644
--- a/TODO
+++ b/TODO
@@ -1,5 +1,6 @@
 TODO TTMath Library
 ===================
 
-* add the method Mod (a remainder from a division) for the Big type
-
+* to add the method Mod (a remainder from a division) for the Big type
+* to add operators (or functions) and, or, xor
+* to add functions for generating random values
diff --git a/ttmath/ttmathtypes.h b/ttmath/ttmathtypes.h
index 327f5e7..07b8fb3 100644
--- a/ttmath/ttmathtypes.h
+++ b/ttmath/ttmathtypes.h
@@ -217,7 +217,8 @@ namespace ttmath
 		err_functions_loop,
 		err_must_be_only_one_value,
 		err_object_exists,
-		err_unknown_object
+		err_unknown_object,
+		err_still_calculating
 	};