Sign Up to our social questions and Answers Engine to ask questions, answer people’s questions, and connect with other people.
Login to our social questions & Answers Engine to ask questions answer people’s questions & connect with other people.
Lost your password? Please enter your email address. You will receive a link and will create a new password via email.
Please briefly explain why you feel this question should be reported.
Please briefly explain why you feel this answer should be reported.
Please briefly explain why you feel this user should be reported.
Basically I’ve a class A and a class B : public A.
And I’d like to cast a std::shared_ptr<std::vector<A*> to a std::shared_ptr<std::vector<B*>
The problem is std::vector<B> doesn’t inherit from std::vector<A>, and the smart_ptr neither. So I do a horrible cast:
std::shared_ptr<VectorA> vector_a = * ((std::shared_ptr<VectorA>*)&vector_b);
The code compiles and runs there, but it is safe?
http://liveworkspace.org/code/3dQTz1$0
Strictly speaking the dereferencing operations should succeed. Both vectors are pointer containers, so casting one to another, whilst unacceptable for production code, will still use the same dimensions and alignment.
C++ provides rich abstractions to avoid these shenanigans though, it would be better to populate the vector of derived objects as pointers to the base class.