#define UNIT r6_bits
#include <iterator>

template< typename num_t >
class bits
{
    struct proxy
    {
        bool _value;
        bool *operator->() { return &_value; }
    };

    struct iterator
    {
        using value_type = bool;
        using reference = bool;
        using pointer = proxy;
        using difference_type = ssize_t;
        using iterator_category = std::input_iterator_tag;

        num_t _value;
        num_t _mask;

        iterator &operator++()
        {
            _mask <<= 1;
            return *this;
        }

        bool operator*() const { return _value & _mask; }
        proxy operator->() const { return { **this }; }

        bool operator==( const iterator &other ) const
        {
            return _mask == other._mask;
        }

        bool operator!=( const iterator &other ) const
        {
            return !( *this == other );
        }
    };

    num_t _value;

public:
    bits( num_t n ) : _value( n ) {}

    iterator begin() const { return { _value, 1 }; }
    iterator end()   const { return { _value, 0 }; }
};

#include "test_main.cpp"