std::indirect_equivalence_relation(3)

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.