C++ - Initializing class member with an instance

Question

my question is as follows: Suppose I have:

class Foo
{
public:
    Foo() {}
    void setInt(int i) { myInt = i; }
    int getInt() { return myInt; }
private:
    int myInt;
};

class Bar
{
public:
    Bar(Foo f) { /* do something with f.getInt() */ }
};

Now I have another class that has Bar as a member vairable:

class BarUser
{
public:
    BarUser();
private:
    Bar bar;
};

I want to write BarUser's constructor, however I want to initialize Bar with a Foo member that has 3 as its integer. I.e.:

Foo f;
f.setInt(3);
Bar b(f);

However since I have Bar as a class member, I cannot write all this code in the initialization list... What I mean is:

BarUser::BarUser() : bar(/* Foo after executing f.setInt(3) */)
{ ... }

Suppose assignment operator is not allowed for Bar - how can I initialize it as intended?

Thanks!

Answer 1

If you can't change Foo, write a function:

Foo make_foo(int i) { 
     Foo f; 
     f.setInt(i); 
     return f;
}

then initialize with bar(make_foo(3)).

You've sort of shot yourself in the foot by giving Foo a constructor but no int constructor. You might be better off adding an explicit constructor to Foo that takes an int.