In the previous two threads entitled:

    "Extend std::type_info with more information"
    "Use the exception system to check for bases at runtime"

People were not much interested in extending "std::type_info", but
rather were particularly interested in adding a new member function to
"std::any".

Here's the beginnings of a paper for std::any::base:

    http://www.virjacode.com/papers/any_base.htm

The implementations are provided in the paper purely just to show that
it's possible without an ABI break. Compiler vendors will implement
it much more efficiently.