void add(value_type start, value_type end)
{
if(end <= start)
return;
// dirty list represents ranges with alternate elements: start,end,start,end
// to insert a new range:
// find insert point of start. find element before, if it is a start element then it is the start of the new range
// otherwise the new insertion is
// find insert point of end. find element after, if it is an end element then it is the end of the new range
// otherwise the new insertion is
std::pair<RangeMap::iterator, bool> sloc = _ranges.insert(RangeRec(start, true));
if(sloc.first != _ranges.begin())
{
RangeMap::iterator prev = sloc.first; prev--;
if(prev->start)
{
sloc.first--;
}
}
std::pair<RangeMap::iterator, bool> eloc = _ranges.insert(RangeRec(end, false));
RangeMap::iterator next = eloc.first; next++;
if(next != _ranges.end() && !next->start)
{
eloc.first++;
}
// erase the interior of the range
++sloc.first;
if(sloc.first != eloc.first && sloc.first != _ranges.end())
{
//eloc.first;
if(sloc.first != eloc.first)
_ranges.erase(sloc.first, eloc.first);
else
_ranges.erase(sloc.first);
}
assert((_ranges.size() - 1) % 2 != 0);
}
bool empty() const
{
return _ranges.size() == 0;
}
