On Tue, Feb 13, 2024 at 12:19 PM Robert Sitton via Std-Proposals <std-proposals@lists.isocpp.org> wrote:
I have included a proposal that draws both our group's discussions and my own research into different languages. Please review this draft and let us know what you think.

This communication contains confidential information and may be privileged.  If you are not the intended recipient or believe that you have received this communication in error, please reply to the sender indicating that fact and delete the copy you received.  You should also not print, copy, re-transmit, disseminate, or otherwise use the information unless expressly indicated in this communication.
Std-Proposals mailing list

std::ranges::contains already exists: https://en.cppreference.com/w/cpp/algorithm/ranges/contains.