void safe_assign1(std::vector<T,A>& a, const std::vector<T,A>& b) {
std::vector<T,A> temp(b.get_allocator());
temp.reserve(b.size());
for(typename std::vector<T,A>::const_iterator p = b.begin(); p != b.end(); ++p)
temp.push_back(*p);
std::swap(a, temp);
}
typename std::vector<item<L>>::allocator_type get_allocator() const
{
return contents.get_allocator();
}