Hi David,
I to am an AS3 novice. Wrote my first(trivial) action script file about
an hour ago. :)
A couple of ideas. Not sure if they will be of much help to you, but
incase you hadnt considered them already..
. you could return the value returned by the call to super.
ie)
Camera c = super.move;
//....// some local x,y stuff
return c;
. you could use an interface as the return value. eg) interface ICamera
would define the move and rotate methods and return an ICamera and your
Camera classes would implement ICamera.
I realise that these options do not do what you asked for, but you might
find one of these is an acceptable alternative.
HTH.
cheers,
- shaun
David_Stafford wrote:
> Please pardon this simple-minded question from an AS3 novice.
>
> My base class often returns 'this' from methods which makes it
> convenient to write code like:
>
> camera.move( 10, 12 ).rotateX( 45 ).rotateY( 90 );
>
> The problem comes when code extends the base class and overrides one
> of these functions. The compiler insists, correctly, that the return
> type of an overriding function must match the one in the base class.
> What I want to do is return the 'this' object that is of the type of
> the derived class. Is this possible?
>
> The following is a contrived example to demonstrate. It won't
> compile because the overridden function in the derived class wants to
> return a type of MyCamera rather than Camera:
>
>
> public class Camera
> {
> var x:int = 0;
> var y:int = 0;
>
> public function move( x:int, y:int ) :Camera
> {
> this.x += x;
> this.y += y;
>
> return( this );
> }
> }
>
> public class MyCamera extends Camera
> {
> override public function move( x:int, y:int ) :MyCamera
> {
> super.move( x, y );
>
> if( x < 0 ) x = 0;
> if( y < 0 ) y = 0;
>
> return( this );
> }
> }
