MustParse is as per Parse except that it panics if the string cannot be parsed.

New returns a new Clock with specified hour, minute, second and millisecond.

NewAt returns a new Clock with specified hour, minute, second and millisecond.

Parse converts a string representation to a Clock.

SinceMidnight returns a new Clock based on a duration since some arbitrary midnight.

Day is a fixed period of 24 hours.

Hour is one hour; it has a similar meaning to time.Hour.

Midnight is the zero value of a Clock.

Minute is one minute; it has a similar meaning to time.Minute.

Noon is at 12pm.

Second is one second; it has a similar meaning to time.Second.

Undefined is provided because the zero value of a Clock *is* defined (i.e.

Clock specifies a time of day.