Static cast

Frank Benoit keinfarbton at
Wed Jun 25 15:57:06 PDT 2008

Jason House schrieb:
> What is the proper way to implement static cast?
> cast(T) to shift with an object/ interface hierarchy is dynamic and slow. My problem is that cast(T)cast(void*) does not honor vtable locations and ClassInfo is only available at runtime.

I you need this only for special classes and not as a general thing...
you can probably give those classes/interfaces a asType Method.

interface I1 {
   T asT();
interface I2 : I1 {

class A : I2 {
   T asT(){ return null; }

class B : A{}
class T : A{
   T asT(){ return this; }

Now the cast is only a virtual method call and no dynamic cast is needed 
and you get null for class which are not T.

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