Interfaces

[alexander Patapoff via Digitalmars-d-learn]

is there a way for me to do this in D? In java, one is able to 
create a new instance of an interface.

interface Action
{
   void actions(T t);
}

class testAction
{
   this()
    {
     Action action = new Action()
        {
          void actions(T t){...}
        }
    }

}

I found this feature really useful in java. Is there any way I 
can duplicate this process, without the mixin func?