On Sun, 29 Jul 2018 at 01:21, Ville Voutilainen <ville.voutilainen@gmail.com> wrote:
Hi! It seems reasonable to enable spaceship operator support
for 3rd party types conditionally. See
https://codereview.qt-project.org/#/c/235303/

I agree.

Perhaps __cpp_spaceship and __cpp_lib_spaceship,
for the language feature and the library support, respectively?

I think I would weakly prefer __cpp_three_way_comparison / __cpp_lib_three_way_comparison.