On Wednesday 31 July 2024 03:53:06 GMT-7 Breno Guimarães via Std-Proposals
wrote:
> for(const aut& elem: vec)
> {
> auto r = elem(0);
> }
>
> Suppose you managed to make the operator() work and return different types
> depending on the value of "elem".
> What size of stack should be allocated for r? What destructor should be
> called for "r"?

This is the same as a std::variant whose template parameters are filled in by
the compiler. The one line in the loop is basically a very large switch block
or a visit:

    elem.vsiit([](auto &realelem) { auto r = realelem(0); });

-- 
Thiago Macieira - thiago (AT) macieira.info - thiago (AT) kde.org
  Principal Engineer - Intel DCAI Platform & System Engineering