从一个模板函数聊聊模板函数里面如何获得T的名字

写了个小程序,遇到点问题.总结总结,学习学习

 #include<vector>
 #include<iostream>
 #include<typeinfo>

 using namespace std;

 enum TYPE
 {
     T_INT,
     T_BOOL,
     T_CHAR,
 };

 template <typename T>
 void printTime( TYPE type )
 {
     clock_t t;
     vector<T> vc;
     t = clock();
     for (int i = ; i < ; i++)
     {
         for (int j = ; j < ; j++)
         {
             //vc.push_back( reinterpret_cast<T>(0) );
             vc.push_back(  );
         }
     }
     t = clock() - t;

     switch (type)  //在这里要根据T打印不同的内容
     {
         case T_INT:
             cout << "'vector<int>::push_back(true)' 1000000 times cost: " << t << endl;
             break;
         case T_BOOL:
             cout << "'vector<bool>::push_back(true)' 1000000 times cost: " << t << endl;
             break;
         case T_CHAR:
             cout << "'vector<char>::push_back(true)' 1000000 times cost: " << t << endl;
             break;
     }

     t = clock();
     for (int i = ; i < ; i++)
     {
         for (int j = ; j < ; j++)
         {
             T value = vc[i *  + j];
         }
     }
     t = clock() - t;
     switch (type)  //在这里要根据T打印不同的内容
     {
         case T_INT:
             cout << "'vector<int>::operator[]' 1000000 times cost: " << t << endl;
             break;
         case T_BOOL:
             cout << "'vector<bool>::operator[]' 1000000 times cost: " << t << endl;
             break;
         case T_CHAR:
             cout << "'vector<char>::operator[]' 1000000 times cost: " << t << endl;
             break;
     }
 }
 int main()
 {
     printTime<int>(T_INT);
     printTime<bool>(T_BOOL);
     printTime<char>(T_CHAR);
     return ;
 }

上面的打印结果是可行的,不过需要用一个枚举感觉很不爽啊..

结果常识了模板和宏结合的方法,结果没打印出理想结果.原因是 宏是先于模板展开的

看程序:

 #include<vector>
 #include<iostream>
 #include<typeinfo>

 using namespace std;

 #define TOSTRING(x) #x

 template <typename T>
 void printTime()
 {
     clock_t t;
     vector<T> vc;
     t = clock();
     for (int i = ; i < ; i++)
     {
         for (int j = ; j < ; j++)
         {
             //vc.push_back( reinterpret_cast<T>(0) );
             vc.push_back(  );
         }
     }
     t = clock() - t;
     cout << "'vector<"<<TOSTRING(T)<<">::push_back(true)' 1000000 times cost: " << t << endl;

     t = clock();
     for (int i = ; i < ; i++)
     {
         for (int j = ; j < ; j++)
         {
             T value = vc[i *  + j];
         }
     }
     t = clock() - t;
     cout << "'vector<"<<TOSTRING(T)<<">::operator[]' 1000000 times cost: " << t << endl;
 }
 int main()
 {
     printTime<int>();
     printTime<bool>();
     printTime<char>();
     return ;
 }

请教了qq群的大神们,介绍了一个叫做typeid的关键字..所以在c++专栏下<typeid是什么>的帖子中学习学习这个东西