Class const_iterator

src/fl/stl/deque.h:161–262

    };

    class const_iterator {
    public:
        typedef T value_type;
        typedef const T& reference;
        typedef const T* pointer;
        typedef fl::size difference_type;
        typedef fl::random_access_iterator_tag iterator_category;

    private:
        const deque* mDeque;
        fl::size mIndex;

        friend class deque;

    public:
        const_iterator(const deque* dq, fl::size index) : mDeque(dq), mIndex(index) {}

        // Implicit conversion from iterator to const_iterator
        const_iterator(const iterator& it) : mDeque(it.mDeque), mIndex(it.mIndex) {}

        const T& operator*() const {
            return (*mDeque)[mIndex];
        }

        const T* operator->() const {
            return &(*mDeque)[mIndex];
        }

        const_iterator& operator++() {
            ++mIndex;
            return *this;
        }

        const_iterator operator++(int) {
            const_iterator temp = *this;
            ++mIndex;
            return temp;
        }

        const_iterator& operator--() {
            --mIndex;
            return *this;
        }

        const_iterator operator--(int) {
            const_iterator temp = *this;
            --mIndex;
            return temp;
        }

        const_iterator& operator+=(fl::size n) {
            mIndex += n;
            return *this;
        }

        const_iterator operator+(fl::size n) const {
            const_iterator temp = *this;
            return temp += n;