Peter Dimov wrote:
David Turner wrote:
Why is cast<> using a what looks like a homebrew RTTI system? Is there something that makes dynamic_pointer_cast<T::element_type>(w) inappropriate?
Mm, er, um, ah... Yes, it is a homebrew RTTI system. It does nothing that could not be achieved with dynamic_cast, but it's a bit less weighty. By the way, the widget types already have names (the static type() members) anyway, as a consequence of the use of window_base as a factory. More on that below.
I think that the important question here isn't "why doesn't cast<> use dynamic_cast<>", but "am I guaranteed to be able to use dynamic_pointer_cast<window::element_type>(w) to obtain a window given a widget w?"
I don't see any immediate reason why not. I'm not doing any nasties with my homebrew system, it just checks if the widget is of the correct actual type and then passes the correct interface by way of a void*. Regards David Turner