On Fri, 27 Feb 2026 at 11:17, Jan Schultke via Std-Proposals <std-proposals@lists.isocpp.org> wrote:
Hi,

https://isocpp.org/files/papers/D4040R0.html

I am proposing to add case ranges to C++. For example, this lets you write:

switch (next_char) {
  case '0' ... '9': // ...
}

Find all the details at the link. Happy to hear any thoughts on the matter.

"Empty case ranges such as case -1 ... 0 are valid, but recommended to be diagnosed. "

Why is that an empty range?