复制构造函数的调用

 1 #include <iostream>
 2 using namespace std;
 3 
 4 class Test
 5 {
 6 public:
 7   Test(int n = 1)
 8   {
 9     val = n;
10     cout << "Con." << endl;
11   }
12 
13   Test(const Test& t)
14   {
15     val = t.val;
16     cout << "Copy con." << endl;
17   }
18 
19   Test& operator=(Test& t)
20   {
21     val = t.val;
22     cout << "Assignment." << endl;
23     return *this;
24   }
25 
26 private:
27   int val;
28 };
29 
30 void func1(Test t)
31 {
32 }
33 
34 Test func2()
35 {
36   Test t;
37   return t;
38 }
39 
40 void main()
41 {
42   Test t1(1);
43 
44   Test t2 = t1; // ①
45 
46   Test t3;
47   t3 = t1;
48 
49   func1(t2); // ②
50 
51   t3 = func2(); // ③
52 }