Multiple Inheritance in C#

Question

Since multiple inheritance is bad (it makes the source more complicated) C# does not provide such a pattern directly. But sometimes it would be helpful to have this ability.

Answer 1

I created a C# post-compiler that enables this kind of thing:

using NRoles;

public interface IFirst { void FirstMethod(); }
public interface ISecond { void SecondMethod(); }

public class RFirst : IFirst, Role {
  public void FirstMethod() { Console.WriteLine("First"); }
}

public class RSecond : ISecond, Role {
  public void SecondMethod() { Console.WriteLine("Second"); }
}

public class FirstAndSecond : Does, Does { }

You can run the post-compiler as a Visual Studio post-build-event:

C:\some_path\nroles-v0.1.0-bin\nutate.exe "$(TargetPath)"

In the same assembly you use it like this:

var fas = new FirstAndSecond();
fas.As().FirstMethod();
fas.As().SecondMethod();

In another assembly you use it like this:

var fas = new FirstAndSecond();
fas.FirstMethod();
fas.SecondMethod();