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  1. #include <iostream>
  2.  
  3.  
  4. class MyClass {
  5. public:
  6.     virtual void show(const std::string& s) const {
  7.         std::cout <<s<<": "<< "I'm a MyClass" << std::endl;
  8.     }
  9. };
  10. class MySubClass : public MyClass{
  11. public:
  12.     int r=10;
  13.     void show(const std::string& s) const override {
  14.         std::cout <<s<<": "<< "I'm a MySubClass with r=" << r << std::endl;
  15.     }
  16. };
  17.  
  18. void test_slicing() {
  19.     MySubClass xyz;
  20.     xyz.show("original object");
  21.     //... // lots of code
  22.     //... // lots of code
  23.     //... // lots of code
  24.     MyClass uvw = xyz; // forgot to replace -> slicing error !
  25.     uvw.show("wrong copy");
  26.     auto tuv = xyz; // let type inference do the job
  27.     tuv.show("right copy");
  28. }
  29.  
  30. int main(int argc, const char * argv[]) {
  31.     test_slicing();
  32. }
Success #stdin #stdout 0.01s 5280KB
comments (?)
stdin 
Standard input is empty
stdout 
original object: I'm a MySubClass with r=10
wrong copy: I'm a MyClass
right copy: I'm a MySubClass with r=10
https://ideone.com/aI2A8h
language:
C++14 (gcc 8.3)
created:
1 year ago
visibility:
secret

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