d problem

error.log

-> % dub build
Checking dependencies in '/mnt/mintdisk/home/ryan/workspace/d-rpg'
Building configuration "application", build type debug
Compiling...
source/ui/widget/rawtext.d(5): Error: undefined identifier Widget

Run 'dub help' for usage information.

soruce_app.d

import ui.widget.rawtext;

void main() {
  auto rt = new RawText();

  rt.draw();
}

source_ui_widget.d

module ui.widget;

class Widget {
  void draw() {
    // Do nothing
  }
}

source_ui_widget_rawtext.d

module ui.widget.rawtext;
import ui.widget;
import std.stdio;

class RawText : Widget {
   void draw() {
     writeln("Hello World");
   }
}

_ is really a /, but gist doesn't let me do that.