fork download
copy 
  1. #include <iostream>
  2.  
  3. using namespace std;
  4.  
  5. class Base {
  6. public:
  7.     virtual void func1() {}
  8.     virtual void func2() {}
  9.     virtual void func3() {}
  10.     virtual ~Base() {}
  11. };
  12.  
  13. template<class B> class Derived1 : public B {
  14. public:
  15.     void func1() {
  16.         cout << "Derived1" << endl;
  17.         B::func1();
  18.     }
  19. };
  20.  
  21. template<class B> class Derived2 : public B {
  22. public:
  23.     void func2() {
  24.         cout << "Derived2" << endl;
  25.         B::func2();
  26.     }
  27. };
  28.  
  29. template<class B> class Derived3 : public B {
  30. public:
  31.     void func3() {
  32.         cout << "Derived3" << endl;
  33.         B::func3();
  34.     }
  35. };
  36.  
  37. int main() {
  38.     typedef Derived1<Derived2<Base>> Foo;
  39.     Base *foo = new Foo;
  40.     foo->func1();
  41.     foo->func2();
  42.     foo->func3();  // do nothing
  43.     cout << "---------\n";
  44.     typedef Derived2<Derived3<Base>> Qoo;
  45.     Base *qoo = new Qoo;
  46.     qoo->func1();  // do nothing
  47.     qoo->func2();
  48.     qoo->func3();
  49.     cout << "---------\n";
  50.     typedef Derived1<Derived1<Base>> Hoo;
  51.     Base *hoo = new Hoo;
  52.     hoo->func1();  // output twice
  53. }
  54.  
Success #stdin #stdout 0s 2964KB
comments (?)
stdin
copy 
Standard input is empty
stdout
copy 
Derived1
Derived2
---------
Derived2
Derived3
---------
Derived1
Derived1
https://ideone.com/SaJ5i
language:
C++14 (gcc 8.3)
created:
13 years ago
visibility:
public

Share or Embed source code

Discover > Sphere Engine API

The brand new service which powers Ideone!

Discover > IDE Widget

Widget for compiling and running the source code in a web browser!