C++模板的特化超详细精讲

void Swap(int& left, int& right)
{
	int temp = left;
	left = right;
	right = temp;
}
void Swap(double& left, double& right)
{
	double temp = left;
	left = right;
	right = temp;
}
void Swap(char& left, char& right)
{
	char temp = left;
	left = right;
	right = temp;
}

template<typename T>
void Swap(T& left, T& right)
{
	T temp = left;
	left = right;
	right = temp;
}

template<class T>
T Add(const T& left, const T& right)
{
	return left + right;
}
int main(){
	int a1 = 10, a2 = 20;
	double d1 = 10.0, d2 = 20.0;
	Add(a1, a2);
	Add(d1, d2);
	//Add(a1, d1);
	Add(a1, (int)d1);
	system("pause");
	return 0;
}

int main(){
	int a = 10;
	double b = 20.0;
	//Add(a, (int)b);//隐式
	Add<int>(a, b);//显示
	system("pause");
	return 0;
}

vector<int> s1;

template<class T>
bool Less(T left, T right){
	return left < right;
}
//特化
template<>
bool Less<Date*>(Date* p1, Date* p2)
{
	cout << "调用的模板函数的特化" << endl;
	return *p1 < *p2;
}
//只要是指针  都可以调用这个，这个思想很重要
//偏特化的带限制条件（指针类型可调）
template<class T>
bool Less(T* left, T* right)
{
	cout << "调用的函数模板" << endl;
	return *left < *right;
}

template<class T>
bool Less(T left, T right){
	return left < right;
}
//特化
template<>
bool Less<Date*>(Date* p1, Date* p2)
{
	cout << "调用的模板函数的特化" << endl;
	return *p1 < *p2;
}

//类模板
template<class T1, class T2>
class data
{
public:
	data(T1 a, T2 b)
		:_a(a)
		, _b(b)
	{
		cout << "data<T1, T2>" << endl;
	}
private:
	T1 _a;
	T2 _b;
};
//全特化
template<>
class data <int, char>
{
public:
	data(int a, char b)
		:_a(a)
		, _b(b)
	{
		cout << "全特化data<int, char>" << endl;
	}
private:
	int _a;
	char _b;
};
int main()
{
	data<int, int> s1(1, 2);
	data<int, char> s2(1, 'a');
}

//类模板
template<class T1, class T2>
class data{
public:
	data(T1 a, T2 b)
		:_a(a)
		, _b(b)
	{
		cout << "data<T1, T2>" << endl;
	}
private:
	T1 _a;
	T2 _b;
};

//半特化
// 1、将模板参数类表中的一部分参数特化。
template<class T1>
class data<T1, char> {
public:
	data(T1 a, char b)
		:_a(a)
		, _b(b)
	{
		cout << "偏特化data<T1, char>" << endl;
	}
private:
	T1 _a;
	char _b;
};

// 2、偏特化并不仅仅是指特化部分参数，而是针对模板参数更进一步的条件限制所设计出来的一个特化版本。
template<class T1, class T2>
class data <T1*, T2* > {
public:
	data(T1 a, char b)
		:_a(a)
		, _b(b)
	{
		cout << "Data<T1*, T2*>" << endl;
	}
private:
	T1 _a;
	T2 _b;
};
template<class T1, class T2>
class data<T1&, T2&>
{
public:
	data(const T1& a, const T2& b)
		:_a(a)
		, _b(b)
	{ cout << "Data<T1&, T2&>" << endl; }
private:
	const T1& _a;
	const T2& _b;
};
int main(){
	data<char*, char*> s6(1,2);
	data<int&, int&> s7(1, 2);
	system("pause");
	return 0;
}