On Wed, Mar 4, 2020, 11:11 AM Sebastian Büttner via Std-Proposals <
std-proposals_at_[hidden]> wrote:

> Sure! You can do this (you were missing the "auto" of the
> placeholder-type-specifier):
> void f(std::basic_string<any_of<char, uint8_t> auto> x);
>

This one is not valid in C++20, but hopefully will become valid in C++23
(although the auto would go outside the template - basic_string<Concept>
auto)

Barry