code: public This getSuper(final Interpreter declaringInterpreter) {
          if (this.parent != null)
              return this.parent.getThis(declaringInterpreter);
          else
              return this.getThis(declaringInterpreter);
      }
docs: Get the parent namespace' This reference or this namespace' This
  reference if we are the top.
  @param declaringInterpreter the declaring interpreter
  @return the super