Function is not implemented.

[Agustin]

I'm trying to move from Java to D, and i have some like this:
interface A
{
  public bool isCancelled();
  public void setCancelled(bool value);
}

class B
{
  public bool isCancelled();
  protected void setCancelled(bool value);
}

But when i do

class C : B, A
{}

I get

Engine/Main.d(6): Error: class Main.C interface function 'bool 
isCancelled()' is not implemented
Engine/Main.d(6): Error: class Main.C interface function 'void 
setCancelled(bool value)' is not implemented