+// Empty unrecognized characters
+class sequence_invalid_load_error : public sequence_load_error
+{
+public:
+ explicit sequence_invalid_load_error(const std::string& msg) :
+ sequence_load_error(msg) {};
+};
+
+//! Error loading sequence annotation
+class annotation_load_error : public sequence_load_error
+{
+public:
+ explicit annotation_load_error(const std::string& msg) :
+ sequence_load_error(msg) {};
+};