Class iterator

tensorflow/core/lib/gtl/flatmap.h:120–178

  key_equal key_eq() const { return rep_.key_eq(); }

  class iterator {
   public:
    typedef typename FlatMap::difference_type difference_type;
    typedef typename FlatMap::value_type value_type;
    typedef typename FlatMap::pointer pointer;
    typedef typename FlatMap::reference reference;
    typedef ::std::forward_iterator_tag iterator_category;

    iterator() : b_(nullptr), end_(nullptr), i_(0) {}

    // Make iterator pointing at first element at or after b.
    iterator(Bucket* b, Bucket* end) : b_(b), end_(end), i_(0) { SkipUnused(); }

    // Make iterator pointing exactly at ith element in b, which must exist.
    iterator(Bucket* b, Bucket* end, uint32 i) : b_(b), end_(end), i_(i) {
      FillValue();
    }

    reference operator*() { return *val(); }
    pointer operator->() { return val(); }
    bool operator==(const iterator& x) const {
      return b_ == x.b_ && i_ == x.i_;
    }
    bool operator!=(const iterator& x) const { return !(*this == x); }
    iterator& operator++() {
      DCHECK(b_ != end_);
      i_++;
      SkipUnused();
      return *this;
    }
    iterator operator++(int /*indicates postfix*/) {
      iterator tmp(*this);
      ++*this;
      return tmp;
    }

   private:
    friend class FlatMap;
    Bucket* b_;
    Bucket* end_;
    char space_ alignas(value_type)[sizeof(value_type)];
    uint32 i_;

    pointer val() { return reinterpret_cast<pointer>(space_); }
    void FillValue() { new (space_) value_type(b_->key(i_), b_->val(i_)); }
    void SkipUnused() {
      while (b_ < end_) {
        if (i_ >= Rep::kWidth) {
          i_ = 0;
          b_++;
        } else if (b_->marker[i_] < 2) {
          i_++;
        } else {
          FillValue();
          break;
        }
      }
    }