# File lib/runt/pdate.rb, line 111
  def PDate.week( yr,mon,day,*ignored )
    #LJK: need to calculate which week this day implies,
    #and then move the day back to the *first* day in that week;
    #note that since rfc2445 defaults to weekstart=monday, I'm 
    #going to use commercial day-of-week
    raw = PDate.day(yr, mon, day)
    cooked = PDate.commercial(raw.cwyear, raw.cweek, 1)
    PDate.civil(WEEK, cooked.year, cooked.month, cooked.day)
  end