std::experimental::ranges::reference_t, std::experimental::ranges::rvalue_reference_t, std::experimental::ranges::iter_common_reference_t

< cpp‎ | experimental‎ | ranges
template <class T>
concept bool /*dereferenceable*/ = requires(T& t) { {*t} -> auto&&; };  // exposition only
template< /*dereferenceable*/ T >
using reference_t = decltype(*declval<T&>());
 (1) (ranges TS)
template< /*dereferenceable*/ T >

  requires requires(T& t) { { ranges::iter_move(t) } -> auto&&; }

using rvalue_reference_t = decltype(ranges::iter_move(declval<T&>()));
 (2) (ranges TS)
template< Readable T >

using iter_common_reference_t = ranges::common_reference_t<ranges::reference_t<T>,

                                                           ranges::value_type_t<T>&>;
 (3) (ranges TS)
1) Obtain the reference type of a dereferenceable type T.
2) Obtain the rvalue reference type of a dereferenceable type T, that is, the return type of ranges::iter_move.
3) Compute a Readable type's common reference type. This is the common reference type of its reference type and an lvalue reference to its value type.

Notes

The -> auto&& constraint checks that the type of the expression is not void.