Re: Why doesn't this multiple virtual inheritance code compile?

Leigh Johnston <>
Tue, 03 Jan 2012 21:51:27 +0000
On 02/01/2012 23:46, Alf P. Steinbach wrote:

On 02.01.2012 21:16, Chris Stankevitz wrote:

My intention is to
- Create an abstract base class "Shape" that must be an "Observer"
- Create an class "Square" that is a "Shape" and also an

I thought I could do this like so:

struct Observer
virtual void Notify() = 0;

struct ObserverImp : public Observer
void Notify() {}

Use virtual inheritance for the interface (that is for `Observer`).

struct Shape : public virtual Observer

struct Square : public Shape, public ObserverImp

Technically OK.

Shape* ShapeFactory()

Please use different naming conventions for types and functions.

Typical Alf nonsense.

This is a style issue and different people use different styles.

For good examples of using the same naming convention for both types and
functions see the C++ standard library.

Personally I use the same naming convention for types and functions
(under_scores) and a different one for variable/object names


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