def delete
      if persisted?
        self.class.delete(id)
        IdentityMap.remove(self) if IdentityMap.enabled?
      end
      @destroyed = true
      freeze
    end
def delete
      if persisted?
        self.class.delete(id)
        IdentityMap.remove(self) if IdentityMap.enabled?
      end
      @destroyed = true
      freeze
    end
Deletes the record in the database and freezes this instance to
 reflect that no changes should be made (since they can't be
 persisted). Returns the frozen instance.

 The row is simply removed with an SQL +DELETE+ statement on the
 record's primary key, and no callbacks are executed.

 To enforce the object's +before_destroy+ and +after_destroy+
 callbacks, Observer methods, or any <tt>:dependent</tt> association
 options, use <tt>#destroy</tt>.