howto dispatch to derived classes?

[Manfred Nowak]

> class C{}
>   class C1:C{}
>   // ...
>   class Cn:C{}
> 
> C getC(){ return new Cn;} // might be extern
>                           // and deliver some Ci
> 
> void visit( C1 fp){}  
> // ...
> void visit( Cn fp){}  
> void main(){
>   visit( getC);           // dispatch?
> }

-manfred
        
          visit( getC);
        }