[chuck-users] parent and children classes (I meant polymorphism)

[Scott Wheeler]

On Jan 20, 2009, at 11:52 PM, eduard aylon wrote:

> Hello Scott,
> thanks for your reply.
> Actually now I realise that my question was incorrect...  too tired  
> due to a project deadline.
> My question, actually, should have been about polymorphism and not  
> inheritance. What I want is that  having a base class Point and  
> another class Point2D which inherits from Point, that I can define a  
> Point  p, that could morph and become a Point2D. Or in other words,  
> that an UGen, can become a SinOsc.
>
> Is that possible?

Still not sure I completely understand -- you can assign a higher  
class to a reference defined as a subclass, and then you can upcast  
that. e.g.

class Foo
{
         fun void f() { <<< 1 >>>; }
}

class Bar extends Foo
{
         fun void f() { <<< 2 >>>; }
}

new Bar @=> Foo @ foo;
foo $ Bar @=> Bar @ bar;

foo.f();
bar.f();

Produces:

2 :(int)
2 :(int)

There's no real "morphing" in there though.  Once a class is  
instantiated it stays the same type, it's just that it can have a  
handle that refers to it that's a base-class or one of its own type.

-Scott