private PeriodFieldSet(Builder builder)
 {
     ticks        = builder.Ticks;
     milliseconds = builder.Milliseconds;
     seconds      = builder.Seconds;
     minutes      = builder.Minutes;
     hours        = builder.Hours;
     days         = builder.Days;
     weeks        = builder.Weeks;
     months       = builder.Months;
     years        = builder.Years;
 }
 internal Builder(PeriodFieldSet baseSet)
 {
     Preconditions.CheckNotNull(baseSet, "baseSet");
     Ticks        = baseSet.Ticks;
     Milliseconds = baseSet.Milliseconds;
     Seconds      = baseSet.Seconds;
     Minutes      = baseSet.Minutes;
     Hours        = baseSet.Hours;
     Days         = baseSet.Days;
     Weeks        = baseSet.Weeks;
     Months       = baseSet.Months;
     Years        = baseSet.Years;
 }