-const char *timer_state_to_string(TimerState i);
-TimerState timer_state_from_string(const char *s);
-
-const char *timer_base_to_string(TimerBase i);
-TimerBase timer_base_from_string(const char *s);
+const char *timer_state_to_string(TimerState i) _const_;
+TimerState timer_state_from_string(const char *s) _pure_;