vector.insert（...）是否会调用构造函数或赋值运算符？

Question

I have a vector with elements of type class A . Class A has an explicitly defined copy constructor, but the copy operator has been made private and undefined (it's not meant to be used). If I insert new elements to the vector like below

A walker;                      //This calls the default constructor.
std::vector< A > vec;
std::vector< A >::iterator it = vec.begin();
vec.insert( it, walker );      //Shouldn't this call the copy constructor?

I get an error complaining that the copy operator is private. But shouldn't vector be using the copy constructor?

Answer 1

vector is indeed using the copy constructor for the inserted element. However vector still needs the assignment operator internally, is within the requeriments for the vector type to be assignable. I believe C++11 now only requres move-assignment.