C++之std::move移动语义的具体实现

template <class _Ty>
_NODISCARD constexpr remove_reference_t<_Ty>&& move(_Ty&& _Arg) noexcept { // forward _Arg as movable
    return static_cast<remove_reference_t<_Ty>&&>(_Arg);
}

template <class _Ty>
using remove_reference_t = typename remove_reference<_Ty>::type;

template <class _Ty>
struct remove_reference {     //原始的，最普通的版本
    using type                 = _Ty;
    using _Const_thru_ref_type = const _Ty;
};

template <class _Ty>
struct remove_reference<_Ty&> {   //左值引用
    using type                 = _Ty;
    using _Const_thru_ref_type = const _Ty&;
};

template <class _Ty>
struct remove_reference<_Ty&&> {  //右值引用
    using type                 = _Ty;
    using _Const_thru_ref_type = const _Ty&&;
};

    std::string old("12212412512");

	std::string new1 = std::move(old); //old变为""

	std::unique_ptr<int>  pValue1(new int{ 5 });
	std::unique_ptr<int>  pValue2 = std::move(pValue1); //pValue1清空

	std::vector<int> pInts = { 0, 1, 2, 3, 4, 5, 67, 1000 };

	std::vector<int> pInt1 = pInts; //pInt1拷贝pInts，和pInts一样

	std::vector<int> pInt2 = std::move(pInts); //pInts清空