class TimeDelta;
class TimeStamp;
-extern TimeStamp now();
-extern std::string format_now(const std::string &);
-extern TimeDelta get_cpu_time();
-extern int sleep(const TimeDelta &);
+/** Returns the current timestamp. */
+TimeStamp now();
+
+std::string format_now(const std::string &);
+
+/** Returns the CPU time used by the program so far. */
+TimeDelta get_cpu_time();
+
+/** Sleeps for the given duration. */
+void sleep(const TimeDelta &);
} // namespace Time
} // namespace Msp