I am almost certain this is not possible. However, there are certainly other ways to do this. What about having a valueObject for each property that stores the values used. Then you could have a GraphicalDisplayObject that you either inherit from or use via composition. For instance:
package {
class FillVO extends Object {
public var fill_color:Number = 0xFF0000;
public var fill_opacity:Number = 0.75;
}
}
package {
import FillVO;
class GraphicalDisplayObject extends Sprite {
public var fill_vo:FillVO;
public function beginFill($vo:FillVO) {
graphics.beginFill($vo.fill_color, $vo.fill_opacity);
}
...
}
}
package {
import GraphicalDisplayObject;
class ObjectWithGraphicalProperties extends Sprite {
public var gfx:GraphicalDisplayObject;
public function ObjectWithGraphicalProperties() {
gfx = new GraphicalDisplayObject();
addChild(gfx);
}
public function beginFill($color:Number, $opactity:Number) {
var fill_vo:FillVO = new FillVO();
fill_vo.fill_color = $color;
fill_vo.fill_opacity = $opacity;
gfx.beginFill(fill_vo);
}
...
}
}
Then to use it...
var obj:ObjectWithGraphicalProperties = new ObjectWithGraphicalProperties();
addChild(obj);
obj.beginFill(0xffff00, .2);
...
...
trace(obj.gfx.fill_vo.fill_color);
This is obviously via composition, and you would need to write the additional proxied methods and corresponding valueObjects... but it should work.