[variant.monostate.relops] (original) (raw)
22 General utilities library [utilities]
22.6 Variants [variant]
22.6.9 monostate relational operators [variant.monostate.relops]
constexpr bool operator==(monostate, monostate) noexcept { return true; } constexpr strong_ordering operator<=>(monostate, monostate) noexcept { return strong_ordering::equal; }
[Note 1:
monostate objects have only a single state; they thus always compare equal.
— _end note_]