On Thu, Apr 11, 2024 at 4:40 PM Tiago Freire via Std-Proposals <std-proposals@lists.isocpp.org> wrote:

 

> All I'm saying is that asking for `any` to support taking out an instance of a base class instead of the actual class stored in it is not unreasonable.

 

Yes, adding an extra feature to std::any is not unreasonable. And dynamic_cast is not the only form of RTTI in the standard, exceptions requires the ability to do it without a vtable, traversing some form of type_info information must already exist to be able to support that, it just so happens to be implementation specific.

 

The problem is the OP is not about changing std::any, but adding sizeof and alignof to std::type_info, which doesn’t help at all to solve any existing issue, including with std::any.


If the OP drops the proposal to change `type_info` and prepares a proposal for changes to `any` instead, would your objections be addressed? Maybe that's the feedback to give?

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