Class iterator_input_adapter

Source/external/json.hpp:6208–6240

// theoretically possible for some containers, but it is extremely versatile.
template<typename IteratorType>
class iterator_input_adapter
{
  public:
	using char_type = typename std::iterator_traits<IteratorType>::value_type;

	iterator_input_adapter(IteratorType first, IteratorType last)
		: current(std::move(first)), end(std::move(last))
	{}

	typename std::char_traits<char_type>::int_type get_character()
	{
		if (JSON_HEDLEY_LIKELY(current != end))
		{
			auto result = std::char_traits<char_type>::to_int_type(*current);
			std::advance(current, 1);
			return result;
		}

		return std::char_traits<char_type>::eof();
	}

  private:
	IteratorType current;
	IteratorType end;

	template<typename BaseInputAdapter, size_t T>
	friend struct wide_string_input_helper;

	bool empty() const
	{
		return current == end;
	}
};


template<typename BaseInputAdapter, size_t T>