C++模板重载

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我是靠谱客的博主还单身苗条，这篇文章主要介绍C++模板重载，现在分享给大家，希望可以做个参考。

C++模板重载

产生背景：需要多个对不同类型使用同一种算法函数时可以使用模板，但是并非所有的类型都使用同一种算法，为了解决这个问题，产生了模板重载。
Tips：
1.如同函数的重载一样，模板重载函数的特征标必须不同
2.并非所有的模板参数都必须是模板参数类型

显示具体化（explicit specialization）：提供一个具体化函数定义
基于（ISO/ANSI C++标准）
C++98标准选择的方法：
1.对于给定的函数名，可以有非模板函数、模板函数和显示具体化模板函数以及它们的重载版本
2.显示具体化的原型和定义应template<>打头，并通过名称来制定类型
3.具体化优先于常规模板，而非模板函数优先于具体化和常规模板

结合代码示例理解

复制代码

#include <iostream>
using namespace std;

template<typename T>
void Swap(T &a,T &b);

struct job{
	char name[40];
	double salary;
	int floor;
};

template<> void Swap<job>(job &j1,job &j2);
void Show(job &j);

int main()
{
	cout.precision(2);
	cout.setf(ios::fixed ,ios::floatfield);
	int i = 10,j = 20;
	cout << "i, j =" << i << " , " << j << endl;
	cout << "Using complier-generated int swapper:n";
	Swap(i,j);
	cout << "Now i, j =" << i << " , " << j << endl;
	job sue = {"Susan Yaffee",73000.60,7};
	job sidney = {"Sidney Taffee",78060.72,9};
	cout << "Before job swapping:n";
	Show(sue);
	Show(sidney);
	Swap(sue,sidney);
	cout << "After job swapping:n";
	Show(sue);
	Show(sidney);
	return 0;
}

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

template<> void Swap<job>(job &j1,job &j2)
{
	double t1;
	int t2;
	t1 = j1.salary;
	j1.salary = j2.salary;
	j2.salary = t1;
	t2 = j1.floor;
	j1.floor = j2.floor;
	j2.floor = t2;
}

void Show(job &j)
{
	cout << j.name  << ": $" << j.salary << " on floor " << j.floor << endl;
}

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#include <iostream>
using namespace std;

template<typename T>
void Swap(T &a,T &b);

struct job{
	char name[40];
	double salary;
	int floor;
};

template<> void Swap<job>(job &j1,job &j2);
void Show(job &j);

int main()
{
	cout.precision(2);
	cout.setf(ios::fixed ,ios::floatfield);
	int i = 10,j = 20;
	cout << "i, j =" << i << " , " << j << endl;
	cout << "Using complier-generated int swapper:n";
	Swap(i,j);
	cout << "Now i, j =" << i << " , " << j << endl;
	job sue = {"Susan Yaffee",73000.60,7};
	job sidney = {"Sidney Taffee",78060.72,9};
	cout << "Before job swapping:n";
	Show(sue);
	Show(sidney);
	Swap(sue,sidney);
	cout << "After job swapping:n";
	Show(sue);
	Show(sidney);
	return 0;
}

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

template<> void Swap<job>(job &j1,job &j2)
{
	double t1;
	int t2;
	t1 = j1.salary;
	j1.salary = j2.salary;
	j2.salary = t1;
	t2 = j1.floor;
	j1.floor = j2.floor;
	j2.floor = t2;
}

void Show(job &j)
{
	cout << j.name  << ": $" << j.salary << " on floor " << j.floor << endl;
}