It seems that Derived class still can access Base::z?
Code:class Base{ public: int z; Base(){ cout<<"Base::Base()"<<endl; } ~Base(){} }; class Derived : private Base{ public: Derived():m1(){ cout<<"Derived::Derived()"<<endl; z=3; } }; int main(){ Derived de; }
Of course Derived can, but what about:
Example:
What happens when you try to use something from a base from this context?Code:class DerviedFromDerived : public Derived { public: DerivedFromDerived() { } };
z is private for derived, so it can access z.
Generally, you will want to use private inheritance to inherit from a class whose contents is not to be part of the public interface (ie what the user of the class can use).
This is because everything inherited, regardless if it's public, protected or private, will become private in the derived class.
You can also use protected inheritance which can be useful if you do not want the contents to be part of the public interface, but make sure the class can be derived from. In protected inheritance, everything but private becomes protected.
Originally Posted by Adak
Are you sure?
I'm pretty sure visibility only becomes more restrictive, not less. i.e. private stays private, public becomes protected...
"I am probably the laziest programmer on the planet, a fact with which anyone who has ever seen my code will agree." - esbo, 11/15/2008
"the internet is a scary place to be thats why i dont use it much." - billet, 03/17/2010
Isn't that what Elysia said?
Damn, nevermind. I didn't see the "but" in there.
"I am probably the laziest programmer on the planet, a fact with which anyone who has ever seen my code will agree." - esbo, 11/15/2008
"the internet is a scary place to be thats why i dont use it much." - billet, 03/17/2010
