Separates == from <=>: defaulted <=> implies a defaulted ==, and != is rewritten from ==.
Other papers in Three-way comparison (<=>)
P0515R3Consistent comparisonAlbuquerque 2017P0768R1Library support for the spaceship (comparison) operatorAlbuquerque 2017P0905R1Symmetry for spaceshipJacksonville 2018P1120R0Consistency improvements for
<=> and other comparison operatorsRapperswil 2018P1186R3When do you actually use <=>?Cologne 2019P1614R2The mothership has landedCologne 2019All 13 papers in Three-way comparison (<=>) →