asbtract class and interface question

[wanting2learn]

Hi, I'm working on a project where I have to modify existing classes etc.

I see the following comment beside an abstract class definition:
// This interface is defined as a class rather than an __interface
// to allow operator delete to be called on it.

1. Can someone explain the difference between an interface vs a class in C++
2. And where one would be used over the other when a asbtract class is defined.

[jsmith]

There is none. Also, __interface is not a keyword in C++, so you should find the definition of it within your source tree.

[helios]

To expand on jsmith's post, the equivalent to an interface from Java or (presumably) C# in C++ would be a class where all member functions are pure virtual. In C++, it's called a pure virtual class.