#include class OldClass { public: int local; OldClass(int x): local(x) { } }; class NewClass { public: int local; NewClass(OldClass o): local(o.local + 1) { } }; int main(void) { OldClass x(1); { NewClass y(x); NewClass x(x); std::cout << "y.local: " << y.local << "; x.local: " << x.local << std::endl; } }