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

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< cpp‎ | experimental‎ | ranges
Experimental
Technical Specification
Filesystem library (filesystem TS)
Library fundamentals (library fundamentals TS)
Library fundamentals 2 (library fundamentals TS v2)
Library fundamentals 3 (library fundamentals TS v3)
Extensions for parallelism (parallelism TS)
Extensions for parallelism 2 (parallelism TS v2)
Extensions for concurrency (concurrency TS)
Extensions for concurrency 2 (concurrency TS v2)
Concepts (concepts TS)
Ranges (ranges TS)
Reflection (reflection TS)
Mathematical special functions (special functions TR)
Experimental Non-TS
Pattern Matching
Linear Algebra
std::execution
Contracts
2D Graphics
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

Notes

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