recursive_pointer_iterator.hpp

#include <cstddef>
#include <type_traits>
#include <cstring>

namespace playground
{
    template<typename T>
    struct count_indirections
    {
        static constexpr std::size_t value = 0;
    };

    template<typename T>
    struct count_indirections<T *>
    {
        static constexpr std::size_t value = count_indirections<T>::value + 1;
    };

    template<typename Pointer>
    class recursive_iterator
    {
    public:
        static constexpr std::size_t current_indirection_level = count_indirections<Pointer>::value;
    private:
        Pointer data;
        std::size_t dimensions[current_indirection_level];
        // ^^ this will give the dimensions of the next  level of indirections

        std::size_t index;
    public:
        recursive_iterator(Pointer data_, const std::size_t (&dimensions_)[current_indirection_level],
                          std::size_t index) :
                data(data_),
                index()
        {
            std::memcpy(dimensions, dimensions_, sizeof(dimensions));
        }

        using element_type = std::remove_pointer_t<Pointer>;

        std::enable_if_t<current_indirection_level, recursive_iterator<element_type>> begin()
        {
            std::size_t next_dimensions[current_indirection_level - 1];
            std::memcpy(next_dimensions, dimensions, sizeof(next_dimensions));
            return {data[index], next_dimensions, 0};
        };

        std::enable_if_t<current_indirection_level, recursive_iterator<element_type>> end()
        {
            std::size_t next_dimensions[current_indirection_level - 1];
            std::memcpy(next_dimensions, dimensions, sizeof(next_dimensions));
            return {data[index], next_dimensions, dimensions[current_indirection_level - 1] - 1};
        };

        recursive_iterator& operator++()
        {
            ++index;
            return *this;
        }

        recursive_iterator operator++(int)
        {
            auto copy= *this;
            ++index;
            return copy;
        }

        element_type operator*()
        {
            return data[index];
        }

        template <typename T>
        friend bool operator==(const recursive_iterator<T>& lhs, const recursive_iterator<T>& rhs);

        template <typename T>
        friend bool operator!=(const recursive_iterator<T>& lhs, const recursive_iterator<T>& rhs);

    private:
        recursive_iterator<element_type> dereference(std::true_type)
        {
            std::size_t next_dimensions[current_indirection_level - 1];
            std::memcpy(next_dimensions, dimensions, sizeof(next_dimensions));
            return {data[index], next_dimensions, 0};
        }

        element_type dereference(std::false_type)
        {
            return data[index];
        }
    };

    template <typename Pointer>
    bool operator==(const recursive_iterator<Pointer>& lhs, const recursive_iterator<Pointer>& rhs)
    {
        return (lhs.data == rhs.data) && (lhs.index == rhs.index);
    }

    template <typename Pointer>
    bool operator!=(const recursive_iterator<Pointer>& lhs, const recursive_iterator<Pointer>& rhs)
    {
        return !(lhs == rhs);
    }

}

The code is under unlicense license. Currently the only problem should be enabling dereferencing, because currenltly it cannot disambiguate between one indirection and multiple indirection case. If anyone can push it to the end, feel free to modify.