通过赋值初始化C ++对象时会发生什么？

Question

From what I understand, assignment uses the operator= function, and initialization uses the contsructor. But when you assign another object during declaration, what happens? I would have thought that car2 would initialize with car1 's data, but I can't tell. Does it initialize with the default constructor first, and then re-assign the data? I tried writing a quick program and traced it with a debugger, but it wouldn't let me look through the important line Car car2 = car1 . I've included my program below.

#include <iostream>
#include <string>

class Car
{
public:
    Car();
    Car(std::string color, std::string make);

private:
    std::string color;
    std::string make;
};

Car::Car() {
    this->color = "None";
    this->make = "None";
}

Car::Car(std::string color, std::string make) {
    this->color = color;
    this->make = make;
}

int main() {
    Car car1("blue", "Toyota");
    Car car2 = car1;
    return 0;
}

Answer 1

Car has an implicitly declared copy-ctor , which is used here as the ctor-call cannot be elided (it is not initialized with a pr-value), nor is move-construction possible (it is not an xvalue).

That implicitly-declared copy-ctor does member-wise copy-construction.