Class set_bit_iterator

cpp/icm/bit_vector.hpp:615–684

    // Iterator support for efficient traversal of set bits
    class set_bit_iterator
    {
    public:
        using iterator_category = std::bidirectional_iterator_tag;
        using value_type = int64_t;
        using difference_type = int64_t;
        using pointer = int64_t*;
        using reference = int64_t&;

    private:
        const bit_vector* bv_;
        int64_t current_position_;

    public:
        set_bit_iterator(const bit_vector* bv, bool at_end = false)
            : bv_(bv)
        {
            if (at_end) {
                current_position_ = bv_->size();
            } else {
                current_position_ = bv_->find_first_set();
            }
        }

        int64_t operator*() const
        {
            ASSERT(current_position_ >= 0);
            return static_cast<int64_t>(current_position_);
        }

        set_bit_iterator& operator++()
        {
            if (current_position_ >= 0) {
                current_position_ = bv_->find_next_set(static_cast<int64_t>(current_position_));
            }
            return *this;
        }

        set_bit_iterator operator++(int)
        {
            set_bit_iterator tmp = *this;
            ++*this;
            return tmp;
        }

        set_bit_iterator& operator--()
        {
            if (current_position_ >= 0) {
                current_position_ = bv_->find_prev_set(static_cast<int64_t>(current_position_));
            }
            return *this;
        }

        set_bit_iterator operator--(int)
        {
            set_bit_iterator tmp = *this;
            --*this;
            return tmp;