std::experimental::ranges::IndirectlyCopyableStorable

template <class In, class Out>

concept bool IndirectlyCopyableStorable =
  IndirectlyCopyable<In, Out> &&
  Writable<Out, const ranges::value_type_t<In>&> &&
  Copyable<ranges::value_type_t<In>> &&
  Constructible<ranges::value_type_t<In>, ranges::reference_t<In>> &&

  Assignable<ranges::value_type_t<In>&, ranges::reference_t<In>>;