howto dispatch to derived classes?

[Manfred Nowak]

=?UTF-8?B?QWxpIMOHZWhyZWxp?= wrote:

> a virtual function like accept() can do the trick

This would require changes in the whole class hierarchy.

But because of
> The actual type of the object is implicitly stored in the
> vtbl of each type.
and in addition, because the statement
| writeln( getC.classinfo.create.classinfo);
gives the correct type there should be a possibility to dispatch to the 
correct `visit' function without any changes in the class hierarchy.

I see that a sequence of statements
| if( auto tmp= cast(Ci) getC) visit( tmp);
can dispatch to the correct `visit' function. But this again would 
require knowledge of all `Ci'.

A solution seems very close, but ...

-manfred