diff --git a/src/errors.h b/src/errors.h
index 7260c30..baf36d5 100644
--- a/src/errors.h
+++ b/src/errors.h
@@ -3529,6 +3529,8 @@
 	INIT(= N_("E1388: Public keyword not supported for a method"));
 EXTERN char e_missing_name_after_implements[]
 	INIT(= N_("E1389: Missing name after implements"));
+EXTERN char e_cannot_use_an_object_variable_except_with_the_new_method_str[]
+	INIT(= N_("E1390: Cannot use an object variable \"this.%s\" except with the \"new\" method"));
 #endif
 EXTERN char e_cannot_mix_positional_and_non_positional_str[]
 	INIT(= N_("E1400: Cannot mix positional and non-positional arguments: %s"));
@@ -3544,4 +3546,4 @@
 	INIT(= N_("E1405: Invalid format specifier: %s"));
 EXTERN char e_aptypes_is_null_nr_str[]
 	INIT(= "E1408: Internal error: ap_types or ap_types[idx] is NULL: %d: %s");
-// E1390 - E1399 unused
+// E1391 - E1399 unused