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  1. #include <vector>
  2. #include <iostream>
  3.  
  4. struct Parent
  5. {
  6. 	void use() { std::cout << "Parent\n"; }
  7. };
  8.  
  9. struct Derived : public Parent
  10. {
  11. 	void use() { std::cout << "Derived\n"; }
  12. };
  13.  
  14. struct Helper
  15. {
  16. 	Helper(Parent *p) : obj(p) {}
  17. 	Parent *const obj;
  18. 	operator Derived *() { return static_cast<Derived *>(obj); }
  19. 	Derived *operator ->() { return static_cast<Derived *>(obj); }
  20. };
  21.  
  22. template <typename T> struct THelper
  23. {
  24. 	THelper(Parent *p) : obj(p) {}
  25. 	Parent *const obj;
  26. 	operator T *() { return static_cast<T *>(obj); }
  27. 	T *operator ->() { return static_cast<T *>(obj); }
  28. };
  29.  
  30. int main()
  31. {
  32.     std::vector<Parent*> objects { new Derived(), new Derived() };
  33.  
  34.     for (Helper h : objects) {
  35.         h->use();
  36.     }
  37.  
  38.     for (THelper<Derived> h : objects) {
  39.         Derived *d = h;
  40.         d->use();
  41.     }
  42.  
  43.     return 0;
  44. }
Success #stdin #stdout 0s 3476KB
comments (?)
stdin 
Standard input is empty
stdout 
Derived
Derived
Derived
Derived
https://ideone.com/ZKNmSI
helper para iterar un array de bases como si fueran derivadas
language:
C++14 (gcc 8.3)
created:
9 years ago
visibility:
secret

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