Anonymous class

[tcak via Digitalmars-d-learn]

I feel like I remember that this was added to D a while ago, but 
I am not sure. Is it possible to create anonymous classes?

public interface Runnable{
    void run();
}

runIt( new Runnable(){
    void run(){
        /* do stuff */
    }
});

I want to do this without making the things any complex.