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>>;