Get count signs in integer

IntegerChecker.hpp

// define

template<
	Types::ullong_t MIN, Types::ullong_t MAX
	, SizeTraits::SizeType BUFFER_SIZE
>
struct NumberChecker
{
	template<typename IntType>
	static inline SizeTraits::SizeType get(IntType value);
};

template<SizeTraits::SizeType BUFFER_SIZE>
struct NumberChecker<
	Types::ullong_t(999999999999999999ULL), Types::ullong_t(9999999999999999999ULL)
	, BUFFER_SIZE
>
{
	template<typename IntType>
	static inline SizeTraits::SizeType get(IntType value);
};

template<typename T, bool SIGNED>
struct BufferSize
{
	static inline SizeTraits::SizeType get(T integer);
};

template<typename T>
struct BufferSize<T, false>
{
	static inline SizeTraits::SizeType get(T integer);
};

// implementation

template<Types::ullong_t MIN, Types::ullong_t MAX, SizeTraits::SizeType BUFFER_SIZE>
template<typename IntType>
inline SizeTraits::SizeType
NumberChecker<MIN, MAX, BUFFER_SIZE>::get(IntType value)
{
	if (MIN <= value && value <= MAX)
		return BUFFER_SIZE;
	else
		return NumberChecker<
			MAX, MAX * Types::ullong_t(10) + Types::ullong_t(9)
			, BUFFER_SIZE + SizeTraits::SizeType(1)
		>::get(value);
}

template<SizeTraits::SizeType BUFFER_SIZE>
template<typename IntType>
inline SizeTraits::SizeType NumberChecker<
	Types::ullong_t(999999999999999999ULL), Types::ullong_t(9999999999999999999ULL)
	, BUFFER_SIZE>::get(IntType value)
{
	constexpr Types::ullong_t MIN = Types::ullong_t(999999999999999999ULL);
	constexpr Types::ullong_t MAX = Types::ullong_t(9999999999999999999ULL);

	if (MIN <= value && value <= MAX)
		return BUFFER_SIZE;
	else
		return BUFFER_SIZE + 1;
}

template<typename IntType, bool SIGNED>
SizeTraits::SizeType BufferSize<IntType, SIGNED>::get(IntType integer)
{
	SizeTraits::SizeType signedValue = 0;
	if (integer < 0)
	{
		++signedValue;
		integer *= -1;
	}
	typename MakeUnsigned<IntType>::Type value = integer;

	return signedValue + NumberChecker<0ULL, 9ULL, 1>::get(value);
}

template<typename IntType>
SizeTraits::SizeType BufferSize<IntType, false>::get(IntType integer)
{
	return NumberChecker<0ULL, 9ULL, 1>::get(integer);
}

template<typename IntType>
SizeTraits::SizeType bufferSize(IntType integer)
{
	return BufferSize<IntType>::get(integer);
}