ceph/src/boost/libs/type_traits/doc/add_rvalue_reference.qbk

   1 [/
   2   Copyright 2010 John Maddock.
   3   Distributed under the Boost Software License, Version 1.0.
   4   (See accompanying file LICENSE_1_0.txt or copy at
   5   http://www.boost.org/LICENSE_1_0.txt).
   6 ]
   7
   8 [section:add_rvalue_reference add_rvalue_reference]
   9
  10    template <class T>
  11    struct add_rvalue_reference
  12    {
  13       typedef __below type;
  14    };
  15
  16 __type If `T` names an object or function type then the member typedef type
  17 shall name `T&&`; otherwise, type shall name `T`. ['\[Note: This rule reflects
  18 the semantics of reference collapsing. For example, when a type `T` names
  19 a type U&, the type `add_rvalue_reference<T>::type` is not an rvalue
  20 reference. -end note\]].
  21
  22 __std_ref 20.7.6.2.
  23
  24 __header ` #include <boost/type_traits/add_rvalue_reference.hpp>` or ` #include <boost/type_traits.hpp>`
  25
  26 [table Examples
  27
  28 [ [Expression] [Result Type]]
  29
  30 [[`add_rvalue_reference<int>::type`][`int&&`]]
  31
  32 [[`add_rvalue_reference<int const&>::type`] [`int const&`]]
  33
  34 [[`add_rvalue_reference<int*>::type`] [`int*&&`]]
  35
  36 [[`add_rvalue_reference<int*&>::type`] [`int*&`]]
  37
  38 [[`add_rvalue_reference<int&&>::type`][`int&&`]]
  39
  40 [[`add_rvalue_reference<void>::type`][`void`]]
  41
  42 ]
  43
  44 __compat In the absence of rvalue-reference support this trait has no effect.
  45
  46 [endsect]
  47