Method iterator_at

lib/swoc/include/swoc/IPRange.h:1498–1501

  IP6Space _ip6; ///< sub-space containing IPv6 ranges.

  iterator
  iterator_at(typename IP4Space::const_iterator const &spot) {
    return iterator(spot, _ip6.begin());
  }
  iterator
  iterator_at(typename IP6Space::const_iterator const &spot) {
    return iterator(_ip4.end(), spot);