I have the following class:
class Base {
public:
Base(string name) {
agg = new Aggregate(name);
}
private:
Aggregate* agg;
};
Now I need to extend this class:
class Derived : Base {
public:
Derived(string name) : Base(name) {
agg2 = new Aggregate2(name);
}
private:
Aggregate2* agg2;
};
What I want is when I create a Base
object, Aggregate
needs to be created and when I create a Derived
object only Aggregate2
should be created.
Now this is not happening because Aggregate
its created inside the constructor which is called when I create a Derived
object and like this Aggregate
and Aggregate2
would be created.
I could move the creation to a different method and call that after creating the object.
Is there any other elegant way to do what I want ?
You may use the following:
class Base {
public:
explicit Base(string name) : agg(new Aggregate(name)) {}
protected:
Base() = default;
private:
std::unique_ptr<Aggregate> agg;
};
class Derived : Base {
public:
// implicit call to Base(), you may be explicit if you want
Derived(string name) : agg2(new Aggregate2(name)) {}
private:
std::unique_ptr<Aggregate2> agg2;
};
Collected from the Internet
Please contact [email protected] to delete if infringement.
Comments