Declare array of Object, within the Object's constructor?

Question

If I have a class, MyClass, can I declare an array of MyClass on the heap, within the constructor of MyClass?

I can do this in C# but it doesnt seem to like it in C++?

I also get an error about no appropriate constructor for type MyClass??

class MyClass
{
    public:
        MyClass(int);
    private
        MyClass* array;
};


MyClass::MyClass(int size){
    array = new MyClass[size];
}

Answer 1

In order to have an array of something, said something has to be default-constructible . Your MyClass isn't since it needs an int to be constructed.

What C# does is comparable to:

MyClass** array = new MyClass*[size];

Where pointers are default constructible, so its allowed. Basically, whenever you do SomeObject in C# its the equivalent of SomeObject* in C++. Except that the code would be horribly inefficient, even worse than its C# counterpart, and there would be leaks everywhere.

Answer 2

You have a more fundamental problem with your approach here than how to construct an array.

Think about it this way:

class A
{
   A* a;
public:
   A();
};
A::A()
{
   a = new A();
}

What happens? You try and create an A ; within the constructor, a new A is created. Within that constructor, another new A is created...

Boom, out of memory.