code: func (a IndexRules) Cutoffs(now time.Time) []int64 {
  	out := make([]int64, len(a.Rules)+1)
  	for i := 0; i <= len(a.Rules); i++ {
  		var rule IndexRule
  		if i < len(a.Rules) {
  			rule = a.Rules[i]
  		} else {
  			rule = a.Default
  		}
  		if rule.MaxStale == 0 {
  			out[i] = 0
  		} else {
  			out[i] = int64(now.Add(rule.MaxStale * -1).Unix())
  		}
  	}
  	return out
  }
docs: // Cutoffs returns a set of cutoffs corresponding to a given timestamp and the set of all rules