std::indirectly_comparable - cppreference.com

From cppreference.com


`template< class I1, class I2, class Comp, class Proj1 = std::identity, class Proj2 = std::identity > concept indirectly_comparable = std::indirect_binary_predicate<Comp, std::projected<I1, Proj1>, std::projected<I2, Proj2>>;`		(since C++20)

The concept indirectly_comparable specifies the fundamental algorithm requirement for comparing values across two independent ranges.

indirectly_comparable is modeled only if all concepts it subsumes are modeled.