std::indirect_equivalence_relation - cppreference.com (original) (raw)

| | | | | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | ------------- | | template< class F, class I1, class I2 = I1 > concept indirect_equivalence_relation = std::indirectly_readable<I1> && std::indirectly_readable<I2> && std::copy_constructible<F> && std::equivalence_relation <F&, /*indirect-value-t*/<I1>, /*indirect-value-t*/<I2>> && std::equivalence_relation <F&, /*indirect-value-t*/<I1>, std::iter_reference_t<I2>> && std::equivalence_relation <F&, std::iter_reference_t<I1>, /*indirect-value-t*/<I2>> && std::equivalence_relation <F&, std::iter_reference_t<I1>, std::iter_reference_t<I2>>; | | (since C++20) |

The concept indirect_equivalence_relation specifies requirements for algorithms that call equivalence relations as their arguments. The key difference between this concept and std::equivalence_relation is that it is applied to the types that I1 and I2 references, rather than I1 and I2 themselves.

[edit] Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.