#include <iostream>
 
 
class MyClass {
public:
    virtual void show(const std::string& s) const {
        std::cout <<s<<": "<< "I'm a MyClass" << std::endl;
    }
};
class MySubClass : public MyClass{
public:
    int r=10;
    void show(const std::string& s) const override {
        std::cout <<s<<": "<< "I'm a MySubClass with r=" << r << std::endl;
    }
};
 
void test_slicing() {
    MySubClass xyz;
    xyz.show("original object");
    //... // lots of code
    //... // lots of code
    //... // lots of code
    MyClass uvw = xyz; // forgot to replace -> slicing error !
    uvw.show("wrong copy");
    auto tuv = xyz; // let type inference do the job
    tuv.show("right copy");
}
 
int main(int argc, const char * argv[]) {
    test_slicing();
}

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