A type L meets the TimedLockable requirements if it meets the Lockable requirements and the following expressions are well-formed and have the specified semantics (m denotes a value of type L, rel_time denotes a value of an instantiation of duration, and abs_time denotes a value of an instantiation of time_point).
m.try_lock_for(rel_time)
Effects: Attempts to acquire a lock for the current execution agent within the relative timeout ([thread.req.timing]) specified by rel_time. The function shall not return within the timeout specified by rel_time unless it has obtained a lock on m for the current execution agent. If an exception is thrown then a lock shall not have been acquired for the current execution agent.
m.try_lock_until(abs_time)
Effects: Attempts to acquire a lock for the current execution agent before the absolute timeout ([thread.req.timing]) specified by abs_time. The function shall not return before the timeout specified by abs_time unless it has obtained a lock on m for the current execution agent. If an exception is thrown then a lock shall not have been acquired for the current execution agent.