Return an iterator providing non-modifiable access to the first business day that occurs on or after the specified date in this calendar. If this calendar has no such business day, the returned iterator has the same value as that returned by endBusinessDays(date). The behavior is undefined unless date is within the valid range of this calendar.
Declared in <bdlt_packedcalendar.h>
PackedCalendar::BusinessDayConstIterator
beginBusinessDays(Date const& date) const;