NAME¶

std::indirect_equivalence_relation - std::indirect_equivalence_relation

Synopsis¶

Defined in header <iterator>
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&, std::iter_value_t<I1>&,
std::iter_value_t<I2>&> &&
std::equivalence_relation<F&, std::iter_value_t<I1>&, (since C++20)
std::iter_reference_t<I2>> &&
std::equivalence_relation<F&, std::iter_reference_t<I1>,
std::iter_value_t<I2>&> &&
std::equivalence_relation<F&, std::iter_reference_t<I1>,
std::iter_reference_t<I2>> &&

std::equivalence_relation<F&, std::iter_common_reference_t<I1>,
std::iter_common_reference_t<I2>>;

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.

Semantic requirements

F, I1, and I2 model indirect_equivalence_relation only if all concepts it subsumes
are modeled.