self operator-(difference_type n) const
Iterator movement operator.
Return another iterator by moving this iterator forward by n elements.
difference_type operator-(const self &itr) const
Iterator distance operator.
Return the index difference of this iterator and itr, so if this iterator sits on an element with a smaller index, this call will return a negative number.
These functions have identical behaviors and semantics as those of db_vector_base_iterator , so please refer to equivalent in that class.