[C++]左值引用与右值引用

[vicyang]

Code: [全选] [展开/折叠] [Download] (ref_to_rvalue.cpp)

1. #include <iostream>
2. #include <string>
3. using namespace std;
4. void test1(string&& a, string&& b)
5. {
6.     cout << "A:" << a << ", B:" << b <<endl;
7. }
8.  
9. void test2(const string& a, const string& b)
10. {
11.     cout << "A:" << a << ", B:" << b <<endl;
12. }
13.  
14. void test3(string& a, string& b)
15. {
16.     cout << "A:" << a << ", B:" << b <<endl;
17. }
18.  
19. int main(int argc, char *argv[] )
20. {
21.     test1( string("abc"), string("123") );
22.     test2( string("abc"), string("123") );
23.     // test3( string("abc"), string("123") ); //error: cannot bind non-const lvalue reference of type
24.     // &ref 是左值引用操作符，字面值常量属于右值，C++规定，右值不能传递给左值引用。
25.     return 0;
26. }